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Sample records for galaxias maculatus teleostei

  1. Mechanisms of zinc toxicity in the galaxiid fish, Galaxias maculatus.

    PubMed

    McRae, Nicole K; Gaw, Sally; Glover, Chris N

    2016-01-01

    Zinc (Zn) is an essential metal, which is ubiquitous in aquatic environments occurring both naturally, and through anthropogenic inputs. This study investigated impacts of sub-lethal Zn exposure in the galaxiid fish Galaxias maculatus. Known as inanga, this amphidromous fish is widespread throughout the Southern hemisphere, but to date almost nothing is known regarding its sensitivity to elevated environmental metals. Fish were exposed to environmentally-relevant concentrations of Zn (control, 8, 270 and 1000μgL(-1)) over 96h. End-points measured included those relating to ionoregulatory disturbance (whole body calcium and sodium influx), oxygen consumption (respirometry), oxidative stress (catalase activity and lipid peroxidation) and whole body accumulation of Zn. Zn exposure caused increases in catalase activity and lipid peroxidation, but only at the highest exposure level tested. Zn also significantly inhibited calcium influx, but stimulated sodium influx, at 1000μgL(-1). The sub-lethal changes induced by Zn exposure in inanga appear to be conserved relative to other, better-studied species. These data are the first to explore the sensitivity of juvenile galaxiid fish to Zn, information that will be critical to ensuring adequate environmental protection of this important species. PMID:26510681

  2. Surviving historical Patagonian landscapes and climate: molecular insights from Galaxias maculatus

    PubMed Central

    2010-01-01

    Background The dynamic geological and climatic histories of temperate South America have played important roles in shaping the contemporary distributions and genetic diversity of endemic freshwater species. We use mitochondria and nuclear sequence variation to investigate the consequences of mountain barriers and Quaternary glacial cycles for patterns of genetic diversity in the diadromous fish Galaxias maculatus in Patagonia (~300 individuals from 36 locations). Results Contemporary populations of G. maculatus, east and west of the Andes in Patagonia, represent a single monophyletic lineage comprising several well supported groups. Mantel tests using control region data revealed a strong positive relationship when geographic distance was modeled according to a scenario of marine dispersal. (r = 0.69, P = 0.055). By contrast, direct distance between regions was poorly correlated with genetic distance (r = -0.05, P = 0.463). Hierarchical AMOVAs using mtDNA revealed that pooling samples according to historical (pre-LGM) oceanic drainage (Pacific vs. Atlantic) explained approximately four times more variance than pooling them into present-day drainage (15.6% vs. 3.7%). Further post-hoc AMOVA tests revealed additional genetic structure between populations east and west of the Chilean Coastal Cordillera (coastal vs. interior). Overall female effective population size appears to have remained relatively constant until roughly 0.5 Ma when population size rapidly increased several orders of magnitude [100× (60×-190×)] to reach contemporary levels. Maximum likelihood analysis of nuclear alleles revealed a poorly supported gene tree which was paraphyletic with respect to mitochondrial-defined haplogroups. Conclusions First diversifying in the central/north-west region of Patagonia, G. maculatus extended its range into Argentina via the southern coastal regions that join the Pacific and Atlantic oceans. More recent gene flow between northern populations involved the most ancient and most derived lineages, and was likely facilitated by drainage reversal(s) during one or more cooling events of the late Pleistocene. Overall female effective population size represents the end result of a widespread and several hundred-fold increase over approximately 0.5 Ma, spanning several climatic fluctuations of the Pleistocene. The minor influence of glacial cycles on the genetic structure and diversity of G. maculatus likely reflects the access to marine refugia during repeated bouts of global cooling. Evidence of genetic structure that was detected on a finer scale between lakes/rivers is most likely the result of both biological attributes (i.e., resident non-migratory behavior and/or landlocking and natal homing in diadromous populations), and the Coastal Cordillera as a dispersal barrier. PMID:20211014

  3. Salinity-dependent mechanisms of copper toxicity in the galaxiid fish, Galaxias maculatus.

    PubMed

    Glover, Chris N; Urbina, Mauricio A; Harley, Rachel A; Lee, Jacqueline A

    2016-05-01

    The euryhaline galaxiid fish, inanga (Galaxias maculatus) is widely spread throughout the Southern hemisphere occupying near-coastal streams that may be elevated in trace elements such as copper (Cu). Despite this, nothing is known regarding their sensitivity to Cu contamination. The mechanisms of Cu toxicity in inanga, and the ameliorating role of salinity, were investigated by acclimating fish to freshwater (FW), 50% seawater (SW), or 100% SW and exposing them to a graded series of Cu concentrations (0-200μgL(-1)) for 48h. Mortality, whole body Cu accumulation, measures of ionoregulatory disturbance (whole body ions, sodium (Na) influx, sodium/potassium ATPase activity) and ammonia excretion were monitored. Toxicity of Cu was greatest in FW, with mortality likely resulting from impaired Na influx. In both FW and 100% SW, ammonia excretion was significantly elevated, an effect opposite to that observed in previous studies, suggesting fundamental differences in the effect of Cu in this species relative to other studied fish. Salinity was protective against Cu toxicity, and physiology seemed to play a more important role than water chemistry in this protection. Inanga are sensitive to waterborne Cu through a conserved impairment of Na ion homeostasis, but some effects of Cu exposure in this species are distinct. Based on effect concentrations, current regulatory tools and limits are likely protective of this species in New Zealand waters. PMID:26966874

  4. Contrasting Genetic Structure and Diversity of Galaxias maculatus (Jenyns, 1848) Along the Chilean Coast: Stock Identification for Fishery Management.

    PubMed

    González-Wevar, Claudio; Salinas, Pilar; Hüne, Mathias; Segovia, Nicolás; Vargas-Chacoff, Luis; Oda, Esteban; Poulin, Elie

    2015-01-01

    Galaxias maculatus (Pisces: Galaxiidae) commonly known as "puye" has a disjunct distribution along the Southern Hemisphere including landlocked and migratory populations at latitudes over 30°S in South America, Australia, Tasmania, and New Zealand. Chilean artisanal fishery of G. maculatus has become less important as a resource due to multiple factors including overexploitation, pollution, introduction of predators, and competitors. At the same time, the current conservation status of the species in Chile is still uncertain. Here, we used mtDNA control region sequences (925bp) to investigate main patterns of genetic diversity and structure in populations from 2 biogeographic areas along the Chilean coast. Extremely high levels of genetic diversity characterize the species, suggesting a low amount of influence of the last glacial cycle over its demography compared with other studies in freshwater and marine South American fishes. However, we recognized contrasting genetic patterns between the Intermediate Area (between 30°S and 42°S) and the Magellanic Province (between 42°S and 56°S). On the one hand, over a narrow geographical range (<200 km) each Intermediate Area estuarine population constitutes a different genetic unit. On the other hand, the Magellanic populations of the species exhibited low levels of differentiation in an area extending for more than 500 km. Such differences may be a consequence of different coastal configurations, oceanographic regimes, and Quaternary glacial histories. Finally, our results support the existence of different stock units for G. maculatus and this information should be integrated in future management strategies and aquaculture programs for this species. PMID:26245779

  5. Differential expression of Na+, K(+)-ATPase α-1 isoforms during seawater acclimation in the amphidromous galaxiid fish Galaxias maculatus.

    PubMed

    Urbina, Mauricio A; Schulte, Patricia M; Bystriansky, Jason S; Glover, Chris N

    2013-04-01

    Inanga (Galaxias maculatus) is an amphidromous fish with a well-known capacity to withstand a wide range of environmental salinities. To investigate the molecular mechanisms facilitating acclimation of inanga to seawater, several isoforms of the Na(+), K(+)-ATPase ion transporter were identified. This included three α-1 (a, b and c), an α-2 and two α-3 (a and b) isoforms. Phylogenetic analysis showed that the inanga α-1a and α-1b formed a clade with the α-1a and α-1b isoforms of rainbow trout, while another clade contained the α-1c isoforms of these species. The expression of all the α-1 isoforms was modulated after seawater exposure (28‰). In gills, the expression of the α-1a isoform was progressively down-regulated after seawater exposure, while the expression of the α-1b isoform was up-regulated. The α-1c isoform behaved similarly to the α-1a, although changes were less dramatic. Physiological indicators of salinity acclimation matched the time frame of the changes observed at the molecular level. A 24-h osmotic shock period was highlighted by small increases in plasma osmolality, plasma Na(+) and a decrease in muscle tissue water content. Thereafter, these values returned close to their pre-exposure (freshwater) values. Na(+), K(+)-ATPase activity showed a decreasing trend over the first 72 h following seawater exposure, but activity increased after 240 h. Our results indicate that inanga is an excellent osmoregulator, an ability that is conferred by the rapid activation of physiological and molecular responses to salinity change. PMID:23142926

  6. Phylogeography in Galaxias maculatus (Jenyns, 1848) along Two Biogeographical Provinces in the Chilean Coast.

    PubMed

    González-Wevar, Claudio A; Salinas, Pilar; Hüne, Mathias; Segovia, Nicolás I; Vargas-Chacoff, Luis; Astorga, Marcela; Cañete, Juan I; Poulin, Elie

    2015-01-01

    Major geologic and climatic changes during the Quaternary exerted a major role in shaping past and contemporary distribution of genetic diversity and structure of aquatic organisms in southern South America. In fact, the northern glacial limit along the Pacific coast, an area of major environmental changes in terms of topography, currents, and water salinity, represents a major biogeographic transition for marine and freshwater species. We used mitochondrial DNA sequences (D-loop) to investigate the consequences of Quaternary glacial cycles over the pattern of genetic diversity and structure of G. maculatus (Pisces: Galaxiidae) along two biogeographical provinces in the Chilean coast. Extreme levels of genetic diversity and strong phylogeographic structure characterize the species suggesting a low amount of influence of the last glacial cycle over its demography. However, we recognized contrasting patterns of genetic diversity and structure between main biogeographical areas here analyzed. Along the Intermediate Area (38°-41° S) each estuarine population constitutes a different unit. In contrast, Magellanic populations (43°-53° S) exhibited low levels of genetic differentiation. Contrasting patterns of genetic diversity and structure recorded in the species between the analyzed biogeographic areas are consistent with the marked differences in abiotic factors (i.e., different coastal configurations, Quaternary glacial histories, and oceanographic regimes) and to inherent characteristics of the species (i.e., salt-tolerance, physiology, and reproductive behavior). PMID:26161896

  7. Phylogeography in Galaxias maculatus (Jenyns, 1848) along Two Biogeographical Provinces in the Chilean Coast

    PubMed Central

    González-Wevar, Claudio A.; Salinas, Pilar; Hüne, Mathias; Segovia, Nicolás I.; Vargas-Chacoff, Luis; Astorga, Marcela; Cañete, Juan I.; Poulin, Elie

    2015-01-01

    Major geologic and climatic changes during the Quaternary exerted a major role in shaping past and contemporary distribution of genetic diversity and structure of aquatic organisms in southern South America. In fact, the northern glacial limit along the Pacific coast, an area of major environmental changes in terms of topography, currents, and water salinity, represents a major biogeographic transition for marine and freshwater species. We used mitochondrial DNA sequences (D-loop) to investigate the consequences of Quaternary glacial cycles over the pattern of genetic diversity and structure of G. maculatus (Pisces: Galaxiidae) along two biogeographical provinces in the Chilean coast. Extreme levels of genetic diversity and strong phylogeographic structure characterize the species suggesting a low amount of influence of the last glacial cycle over its demography. However, we recognized contrasting patterns of genetic diversity and structure between main biogeographical areas here analyzed. Along the Intermediate Area (38°–41° S) each estuarine population constitutes a different unit. In contrast, Magellanic populations (43°–53° S) exhibited low levels of genetic differentiation. Contrasting patterns of genetic diversity and structure recorded in the species between the analyzed biogeographic areas are consistent with the marked differences in abiotic factors (i.e., different coastal configurations, Quaternary glacial histories, and oceanographic regimes) and to inherent characteristics of the species (i.e., salt-tolerance, physiology, and reproductive behavior). PMID:26161896

  8. Activity of the ovarian germinal epithelium in the freshwater catfish, Pimelodus maculatus (Teleostei: Ostariophysi: Siluriformes): germline cysts, follicle formation and oocyte development.

    PubMed

    Quagio-Grassiotto, Irani; Grier, Harry; Mazzoni, Talita Sarah; Nbrega, Rafael Henrique; de Arruda Amorim, Joo Paulo

    2011-11-01

    Distinct types of oogonia are found in the germinal epithelium that borders the ovarian lamellae of Pimelodus maculatus: A-undifferentiated, A-differentiated and B-oogonia. This is similar to the situation observed for spermatogonia in the vertebrate testis. The single A-undifferentiated oogonia divide by mitosis giving rise to A-groups of single differentiated oogonia, each enclosed by epithelial cells that are prefollicle cells. Subsequently, the single A-differentiated oogonia proliferate to generate B-oogonia that are interconnected by cytoplasmic bridges, hence, forming germline cysts. The prefollicle cells associated with them also divide. Within the germline cysts, B-oogonia enter meiosis becoming oocytes. Meiotic prophase and early folliculogenesis occur within the germline cysts. During folliculogenesis, prefollicle cells grow between the oocytes, encompassing and individualizing each of them. The intercellular bridges disappear, and the germline cysts are broken down. Next, a basement membrane begins to form around the nascent follicle, separating an oocyte and its associated prefollicle cells from the cell nest. Folliculogenesis is completed when the oocyte and the now follicle cells are totally encompassed by a basement membrane. Cells derived from the ovarian stroma encompass the newly-formed ovarian follicle, and become the theca, thereby completing the formation of the follicle complex. Follicle complexes remain attached to the germinal epithelium as they share a portion of basement membrane. This attachment site is where the oocyte is released during ovulation. The postovulatory follicle complex is continuous with the germinal epithelium as both are supported by a continuous basement membrane. The findings in P. maculatus reinforce the hypothesis that ovarian follicle formation represents a conserved process throughout vertebrate evolution. PMID:21630323

  9. Modelo de galaxia disco

    NASA Astrophysics Data System (ADS)

    Ledesma, M.; Mosconi, M.

    El objetivo de este trabajo es estudiar la formacin de galaxias anillo, a travs de simulaciones numricas. En el estudio numrico es necesario construir el modelo de una galaxia disco normal, en condicin de equilibrio estable, que se ajuste a los parmetros observacionales disponibles de estos objetos. En dicho modelo se considera la galaxia constituda por un halo de materia oscura, un bulge y el disco propiamente dicho. A partir de perfiles de densidad obtenidos de las observaciones, se lleva a cabo la distribucin espacial de las partculas, a travs del ``Mtodo del rechazo". La asignacin de velocidades se realiza considerando que las partculas del disco estn aproximadamente en equilibrio rotacional, y se agregan dispersiones de velocidad de acuerdo con el parmetro de Toomre Q=1.5.

  10. Galaxias australes con ncleo doble

    NASA Astrophysics Data System (ADS)

    Gimeno, G.; Daz, R.; Carranza, G.

    Se estudia una muestra de galaxias australes con ncleo doble a partir de una bsqueda extensiva en la literatura. Se analizan las caractersticas morfolgicas, fotomtricas y espectroscpicas de la muestra. Para algunas galaxias se han realizado observaciones con el espectrgrafo multifuncin (EMF) de la Estacin Astrofsica de Bosque Alegre a partir de las cuales se determinaron parmetros cinemticos.

  11. Nuevas Galaxias Seyfert 1 Australes

    NASA Astrophysics Data System (ADS)

    Maza, J.; Ruiz, M. T.

    1987-05-01

    En 1984 se inici una extensin del "survey" de Tololo que de- sarrollara en 1975 Smith, con la cmara Curtis-Schmidt y el prisma UV delgado. Utilizando placas IIIaJ horneadas, sin filtro, expues tas 90 minutos sin ensanchamiento se han obtenido a la fecha ms de 150 placas que cubren la zona entre -20 y -45 a latitudes galcticas mayores de 20; se presenta un detalle de las franjas que comprende el survey Calan-Tololo, indicando el grado de completitud de las mismas. Se ha encontrado un gran nmero de galaxias con lneas de emisin entre las cuales las ms frecuentes, ms de 300, son galaxias irregulares con formacin estelar violenta ("starburst galaxies"). Se ha encontrado un nmero de cuasares cercano a 100; casi todos ellos tienen la linea Lyman alfa en la zona entre 3300 y 5300 A, que corresponde a un rango de corrimientosal rojo 1.7< z <3.3 el cuasar con mayor corri- miento al rojo encontrado a la fecha en el survey tiene z = 3.1. La informacin detallada sobre cuasares y galaxias tipo "starburst" ser presentada en otro lugar. Entre los objetos ms interesantes encontrados en el survey Caln- Tololo destacan unas 50 nuevas galaxias Seyfert 1. Estas galaxias han sido encontradas por su fuerte exceso UV y su brillante ncleo, ms que por sus intensas lineas de emisin. Hemos observado espectroscpicamente, en el Observatorio Interamericano de Cerro Tololo, 37 de ellas para las cuales se presentan cartas de identificacin, coordenadas y los datos espectroscpicos obtenidos.

  12. Poblacin de galaxias de baja luminosidad en cmulos

    NASA Astrophysics Data System (ADS)

    Valotto, C. A.; Muriel, H.; Moore, B.; Garca Lambas, D.

    En este trabajo se discute sobre la presencia de un exceso de galaxias de baja luminosidad en medios de alta densidad de galaxias y la posibilidad de que los halos de galaxias cD puedan ser formados a partir de galaxias en cmulos ricos, los cuales muestran una funcin de luminosidad (FL) con el extremo dbil plano. Se analizaron muestras de cmulos cercanos obtenidas a partir de los catlogos de Abell y X-ray Sample of Bright Clusters. Los resultados obtenidos muestran que los cmulos de galaxias que tienen emisin en rayos X detectada poseen una FL plana (? ? -1.2), consistente con los valores encontrados para las galaxias de campo. En cambio, los cmulos de galaxias identificados a partir de distribuciones bidimensionales de galaxias que no tienen su contraparte en rayos X, muestran una FL con una pendiente pronunciada en el extremo dbil (? ? -1.6). Se examinaron adems, los posibles efectos debido a la presencia de una galaxia central dominante sobre el extremo dbil de la FL. Se analizaron muestras de acuerdo a la clasificacin Bautz-Morgan dividiendo en las submuestras I,I-II y II, II- III, III. Las FL resultantes para ambas muestras son indistinguibles. Nuestros resultados son consistentes con la hiptesis de que los efectos de proyeccin en cmulos identificados en dos dimensiones pueden producir un exceso artificial de galaxias de baja luminosidad.

  13. Fotometra superficial de la galaxia irregular NGC 1427A

    NASA Astrophysics Data System (ADS)

    Cellone, S. A.; Forte, J. C.

    Se presenta fotometra superficial multicolor de la galaxia irregular NGC 1427A. Esta galaxia, un miembro del Cmulo de Fornax que no ha sido estudiado previamente, muestra una morfologa muy particular: una distribucin estelar subyacente de bajo brillo superficial (LSB) con varias manchas brillantes dispuestas en una estructura anular deformada. Por sus colores muy azules se infiere que estas son zonas de formacin estelar reciente. Al norte del cuerpo principal de la galaxia, y conectado con ste mediante filamentos LSB, hay un objeto de isofotas aproximadamente circulares. Este objeto tiene en s mismo algunas zonas brillantes, pero su poblacin estelar subyacente es significativamente ms azul que la del cuerpo principal de la galaxia. Esto indica que ambos objetos han tenido distintas historias evolutivas. Estructuralmente, el objeto del norte es muy similar a algunas de las galaxias elpticas enanas ms dbiles que pueblan el Cmulo de Fornax. Se discute la posible relacin entre este objeto y la galaxia en si.

  14. Curva de rotacin de la Galaxia Eso 321-25

    NASA Astrophysics Data System (ADS)

    Daz, R.; Carranza, G.; Ahumada, J.; Arreguine, V.

    Se presenta la curva de rotacin de esta galaxia, generada a partir de espectros obtenidos con el Espectrgrafo Multifuncin del telescopio de 1.54 m de Bosque Alegre. El anlisis de las curvas de velocidad radial obtenidas muestra que el ncleo no coincide con el centro de simetra de las mismas, lo que es consistente con el aspecto morfolgico exhibido por la galaxia en imgenes de banda ancha. En estas ltimas, el ncleo muestra una estructura peculiar y no coincidira con el centro geomtrico del disco aparente. Los flujos relativos de lneas (H? /[NII]? 6583 y [SII]? 6731/? 6716) indicaran niveles de excitacin y densidad electrnica normales en regiones HII, an en la zona nuclear. Este trabajo forma parte de un programa de estudio de cinemtica, excitacin y densidad electrnica del gas ionizado en galaxias peculiares del Atlas de Galaxias Australes de Srsic.

  15. Possible sub-glacial eruptions in the Galaxias Quadrangle, Mars

    NASA Astrophysics Data System (ADS)

    Mouginis-Mark, Peter J.; Wilson, Lionel

    2016-03-01

    We have identified several landforms in the Galaxias Quadrangle of Mars (MTM 35217), 33.0-35.5°N, 216.0-218.0°W which are consistent with this area having been covered by an ancient ice sheet concurrent with volcanic eruptions. Volcanic activity was initiated by the intrusion of several large dikes measuring ∼50-100 m wide and protruding up to ∼35 m above the present-day surface. These dikes appear to have originated from Elysium Planitia ∼600 km to the SE. In one instance, a dike (at an elevation of -3750 m) appears to have produced a subglacial mound (referred to here as "Galaxias Mons 2") that evolved into an extrusive eruption and produced copious volumes of melt water that carved an outflow channel that extends almost 300 km to the north. At a lower elevation (-3980 m), a second putative dike may have failed to break the surface of the ice sheet and formed Galaxias Mons as a laccolithic intrusion. We numerically model the formation of Galaxias Mons and find that at least 200 m of ice may once have existed at this latitude at the time of the dike intrusions. Such a conclusion supports the idea that enigmatic small domes in the area may be pingoes. Collectively, these observations suggest that the previous interpretations for the origin of near-by Hrad Vallis as a sub-aerial eruption may need to be revised.

  16. Perfiles de luminosidad en galaxias con ncleo tipo Seyfert 1

    NASA Astrophysics Data System (ADS)

    Boris, N.; Rodriguez-Ardilla, A. A.; Pastoriza, M. G.

    Presentamos imgenes CCD en los filtros BVI y H? de una muestra de 10 galaxias Seyfert 1 y Narrow Line Seyfert 1. Recientes observaciones muestran que hay una diferencia significante en el ndice espectral ptico entre NLS1s y Sy1 normales, siendo para las primeras del orden de 2. Otra caracterstica importante es que la mayor parte de las NLS1s muestran tasas de FeII/H? mayores que las observadas en otras Sy1s. Desde el punto de vista fotomtrico, estas galaxias no tienenningn tipo de estudio previo. Presentamos magnitudes totales, perfiles de luminosidad y mapas de color junto con un detallado anlisis de la formacin estelar en estos objetos. Encontramos que la descomposicin en bulbo + disco representa adecuadamente los perfiles de luminosidad de las galaxias de la muestra. Sin embargo, en todos los casos es necesario que el disco tenga un agujero en su centro. El radio de este agujero va desde los 3 a los 9 kpc. Si bien no tenemos an una explicacin para este hecho, los agujeros parecen estar asociados a anillos circumnucleares de alto oscurecimiento E(B-V) ~1. Los perfiles presentan tambin un fuerte gradiente de color, siendo notablemente ms azules hacia la regin nuclear. Los objetos de la muestra cubren todo el rango de tipos morfolgicos, no obstante, no encontramos regiones de formacin estelar en las regiones exteriores de las galaxias. La formacin estelar est confinada a la regin nuclear y se data en alrededor de 5 x 107 aos.

  17. Catlogo de mapas de HI en Galaxias y anlisis de los datos

    NASA Astrophysics Data System (ADS)

    Martn, M. C.

    Se presenta un catlogo de observaciones de HI en extenso en galaxias, publicadas en las principales revistas hasta 1993. Algunos de los mapas catalogados fueron analizados segn simples modelos de distribucin gausiana, con el objeto de conseguir un valor aproximado de la extensin real del gas. As se ha encontrado que dicha extensin se relaciona con el tamao ptico de la galaxia, y se ha obtenido una expresin numrica que permite estimar ``a priori" la dimensin de la componente gaseosa dentro de una galaxia, conociendo la emisin global del gas obtenida en una observacin simple, y su dimensin ptica.

  18. El origen de las galaxias en modelos jerrquicos de formacin de la estructura

    NASA Astrophysics Data System (ADS)

    Navarro, J. F.

    En esta charla presentar una revisin de los modelos corrientes de formacin de galaxias. En particular, har nfasis en el origen de la gran variedad de morfologas galcticas y de las correlaciones entre las propiedades estructurales de discos y esferoides, todo dentro del contexto cosmolgico jerrquico provisto por teoras como la de materia oscura fra. En este tipo de teoras las correlaciones observadas entre la luminosidad, velocidad de rotacin, momento angular, y tamao de galaxias son el resultado de la falta de escalas naturales en el proceso de formacin de los halos de materia oscura que dichas galaxias habitan. Simulaciones numricas que incorporan efectos gravitacionales, hidrodinmicos y de formacin estelar ilustran estas ideas y demuestran las dificultades que aquejan a modelos donde tanto discos como esferoides son el resultado final de una secuencia de fusiones de sistemas protogalcticos.

  19. Fotometra de grupos compactos de galaxias: Shakhbazian 37, 45, 166, 331 y 362

    NASA Astrophysics Data System (ADS)

    Campos, J. M.; Caldern, J. H.; Gimeno, N. G.; Daz, R. J.

    Continuando con la fotometra CCD de Grupos de Galaxias Compactos de Shakhbazyan (SCGG) en este trabajo se presentan nuevos resultados preliminares sobre los grupos Shakbazyan 37, 45, 166, 331 y 362. EL objeto del proyecto es contribuir al estudio de las propiedades fsicas de tales grupos y contribuir a las bases de datos para mejora de las estadsticas. Los datos fueron adquiridos con el Telescopio JKT del Observatorio Norte Europeo. El anlisis de las imgenes en las bandas I y B como del ndice de color B-I permiti reidentificar las galaxias catalogadas, resultando las mismas muy enrojecidas y verificando que predominan las galaxias tempranas, resultados consistentes con los obtenidos para otros grupos y por otros autores.

  20. Cmulos globulares como trazadores de bimodalidad estelar en galaxias cD

    NASA Astrophysics Data System (ADS)

    Forte, J. C.

    Se muestra que tanto la forma de los perfiles de brillo como de color observados en dos galaxias arquetpicas de tipo cD (NGC 1399 y NGC 4486) son compatibles con la presencia de poblaciones estelares bi-modales que comparten la misma distribucin espacial y composicin qumica de las familias dominantes de cmulos globulares asociadas con ellas. El modelo resultante tambin predice una variacin de la frecuencia especfica de los cmulos como funcin del radio galactocntrico. Se discute este resultado en el contexto de una variedad de escenarios astrofsicos que intentan describir la formacin de galaxias cD.

  1. Dispersión de velocidades en cúmulos de galaxias

    NASA Astrophysics Data System (ADS)

    Muriel, H.; García Lambas, D.; Quintana, H.; Infante, L.

    Se ha estudiado la dinámica de galaxias en cúmulos en base a una muestra de aproximadamente 4000 galaxias con estimas de velocidad radial pertenecientes a 40 cúmulos. Se desarrolló un algoritmo para identificar sub-estructuras del tipo ``grupos de galaxias". Una vez eliminada este tipo de sub-estructura se computaron los perfiles radiales de dispersión de velocidades (VDP) para los 40 cúmulos de galaxias. Dada las características de la muestra, fue posible estimar el VDP hasta grandes distancias del centro del cúmulo llegando en algunos casos hasta 7 Mpc-1. Los resultados indican que el 65% de los cúmulos presentan un VDP plano a grandes radios consistente con el modelo isotermo. Estos resultados son discutidos en el marco de las recientes controversias suscitadas respecto de la dinámica de los cúmulos vía los perfiles de temperaturas de cúmulos derivados de la emisión en rayos-X.

  2. Geologic map of the Galaxias quadrangle (MTM 35217) of Mars

    USGS Publications Warehouse

    De Hon, Rene A.; Mouginis-Mark, Peter J.; Brick, Eugene E.

    1999-01-01

    The Galaxias region (MTM 35217) is one of a series of 1:500,000-scale science study areas on Mars sponsored by NASA's Planetary Geology and Geophysics Program. Situated near the northern limit of lava flows associated with Elysium Mons, this region includes a mixture of volcanic and nonvolcanic terrains. The region is also of interest for the fluvial systems that originate along the distal margins of the Elysium lava flows. Resolution of Viking Orbiter images used to prepare the base map ranges from 40 to 160 m/pixel. High-resolution frames (40 to 80 m/pixel) are found in the southeastern part of the map area and along the north edge of the quadrangle, but over half the quadrangle is included in medium-resolution frames (150 m/pixel). Two 8 m/pixel, very high resolution scenes are available (see fig. 1). Interpretation is complicated by variable resolution and sun angles that vary from east to west illumination on different images. Mapping methods and principles are adapted from those developed for lunar photogeologic mapping by Shoemaker and Hackman (1962), refined by Wilhelms (1972), and successfully applied by many workers to a variety of planetary surfaces. Mapping units are distinguished by topography and texture and are ranked by relative age on the basis of superposition and transection relations. Material units are assigned to time-stratigraphic systems defined by Scott and Carr (1978) and Tanaka (1986). This area is included within earlier maps that used Mariner 9 images at 1:5,000,000 scale (Elston, 1979) and globally at 1:25,000,000 scale (Scott and Carr, 1978). Regional maps based on the much higher resolutions of Viking Orbiter allowed more detailed discrimination of materials by Greeley and Guest (1987) at 1:15,000,000 scale and Tanaka and others (1992) at 1:5,000,000 scale. Some map units on this 1:500,000-scale map correspond to, or are partially equivalent to, units on the larger scale maps of Greeley and Guest (1987) and Tanaka and others (1992). Established terminology is used where feasible, but the scale of this map requires that some new units be introduced and that some previous terminology be redefined. Photogeologic methods are limited; therefore, more than one geologic explanation is given for some material units that do not readily lend themselves to an unequivocal interpretation.

  3. Toxicity of hydrolyzed vicilins toward Callosobruchus maculatus and phytopathogenic fungi.

    PubMed

    Ucha, Adriana Ferreira; de Miranda, Maria Raquel Alcntara; de Souza, Amanda Jardim; Gomes, Valdirene Moreira; Fernandes, Ktia Valevski Sales; Lemos, Francisco Jos Alves; Oliveira, Antonia Elenir Amancio; Xavier-Filho, Jos

    2009-09-01

    Studies have shown that vicilins (7S storage proteins) from seeds were able to bind to the surface of the Callosobruchus maculatus larval midgut and to the peritrophic matrices of the midguts of Diatraea saccharalis and Tenebrio molitor , inhibiting larval development. Vicilins were also shown to inhibit yeast growth and bind to yeast cells through the association with chitin-containing structures. The present work studies the association of peptides from vicilins of genotypes of Vigna unguiculata (susceptible and resistant to bruchid) with acetylated chitin and the toxicity of vicilin fragments and chitin-binding vicilin fragments to C. maculatus and phytopathogenic fungi. Hydrolysis of vicilins with alpha-chymotrypsin results in a complex mixture of fragments that were separated by chitin-affinity chromatography. Chitin-binding peptides from both genotypes were toxic to C. maculatus larvae, and alpha-chymotrypsin-hydrolyzed vicilins were deleterious to the above insect and to Fusarium oxysporum , Colletotrichum musae , and Saccharomyces cerevisiae fungi. PMID:19658384

  4. POPULATION GENETIC STRUCTURE OF ANOPHELES MACULATUS IN THAILAND

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anopheles (Cellia) maculatus Theobald is a major malaria vector in southern Thailand and peninsular Malaysia, and previous studies on the population genetics of this mosquito suggested that mountain ranges reduced gene flow among some populations. In this study we examine the genetic variance among...

  5. Tubulated bodies in teleost (Pimelodus maculatus) endothelial cells.

    PubMed

    Ferri, S; Sesso, A

    1983-01-01

    In the present report tubulated granules are described for the first time in a freshwater teleost (Pimelodus maculatus) endothelial cells. Some ultrastructural characteristics as well as the localization and distribution suggest that tubulated bodies represent the teleost counterpart of the Weibel-Palade bodies described in other animal classes. PMID:6639042

  6. Chaos formation by sublimation of volatile-rich substrate: Evidence from Galaxias Chaos, Mars

    NASA Astrophysics Data System (ADS)

    Pedersen, G. B. M.; Head, J. W.

    2011-01-01

    Galaxias Chaos deviates significantly from other chaotic regions due to the lack of associated outflow channels, lack of big elevation differences between the chaos and the surrounding terrain and due to gradual trough formation. A sequence of troughs in different stages is observed, and examples of closed troughs within blocks suggest that the trough formation is governed by a local stress field rather than a regional stress field. Moreover, geomorphic evidence suggests that Galaxias Chaos is capped by Elysium lavas, which superpose an unstable subsurface layer that causes chaotic tilting of blocks and trough formation. Based on regional mapping we suggest a formation model, where Vastitas Borealis Formation embedded between Elysium lavas is the unstable subsurface material, because gradual volatile loss causes shrinkage and differential substrate movement. This process undermines the lava cap, depressions form and gradually troughs develop producing a jigsaw puzzle of blocks due to trough coalescence. Observations of chaos west of Elysium Rise indicate that this process might have been widespread along the contact between Vastitas Borealis Formation and Elysium lavas. However, the chaotic regions have probably been superposed by Elysium/Utopia flows to the NW of Elysium Rise, and partly submerged with younger lavas to the west.

  7. Estudio de la transparencia de las nubes de Magallanes a partir de la observacin espectroscpica de galaxias ubicadas en direccin a las mismas

    NASA Astrophysics Data System (ADS)

    Dutra, C.; Bica, E.; Clari, J. J.; Piatti, A. E.:

    Se presentan los primeros resultados obtenidos a partir de observaciones espectroscpicas de galaxias ubicadas en direccin a las Nubes de Magallanes. Los espectros fueron obtenidos con el telescopio de 2.15 m del CASLEO y cubren el rango 3500-7000 . El material observacional recolectado permite examinar poblaciones estelares y determinar el enrojecimiento interestelar que afecta a cada una de las galaxias. La distribucin angular de la muestra de galaxias observadas permite efectuar el mapeamiento del enrojecimiento que afecta las distintas regiones de las Nubes de Magallanes.

  8. Electron microscopic study of teleost (Pimelodus maculatus) pancreatic islet cells.

    PubMed

    Ferri, S; Stipp, A C

    1984-01-01

    The endocrine pancreas of the freshwater teleost Pimelodus maculatus was studied by electron microscopy. Based on the granule morphology 2 cell types were described: Secretory granules of type I cells are rounded, nearly completely filling the limiting membranous sac which measures from 120 to 150 nm in diameter; the type II granules are also rounded and measure from 220 to 270 nm in diameter; they consist of an eccentrical electron dense core separated from the limiting membrane by a wide electron lucent halo. These characteristics are correlated with those found in other teleosts. PMID:6370782

  9. Temperature induced transformation of teleost (Pimelodus maculatus) epidermal cells.

    PubMed

    Ferri, S

    1982-01-01

    Superficial epidermal cells of the teleost Pimelodus maculatus show modifications after heat exposure (36 degrees C) for 3 days. Heat treatment affects the arrangement of cytoplasmic filaments resulting in the disappearance of the microridges. The fish maintained at 36 degrees C during 3 days show modifications in the cytoplasmic organization of their superficial epidermal cells. The most conspicuous alterations are: apparition of lysosomes (including autolysosomes), hypertrophy of the GOLGI complexes, disappearance of the RER, and modifications in the nuclear envelope. Epidermal cells maintained at 36 degrees C for 10 days are transformed into horny-like cells. The differences and resemblances with keratinized cells of terrestrial vertebrates are described and discussed. PMID:6891352

  10. Population genetic structure of Anopheles maculatus in Thailand.

    PubMed

    Rongnopaurt, Pornpimol; Rodpradit, Prinyada; Kongsawadworakul, Panida; Sithiprasasna, Ratana; Linthicum, Kenneth J

    2006-06-01

    Anopheles (Cellia) maculatus Theobald is a major malaria vector in southern Thailand and peninsular Malaysia, and previous population genetic studies suggested that mountain ranges act as barriers to gene flow. In this study, we examine the genetic variance among 12 collections of natural populations in southern Thailand by analyzing 7 microsatellite loci. Based on analysis of molecular variance (AMOVA), three geographic populations of An. maculatus are suggested. The southern population exists in western Thailand north of 12 degrees north latitude. Mosquitoes to the south fall into two genetic populations: 1) the middle southern collections located on the west side of the Phuket mountain range between 8 degrees and 10 degrees north latitude, and 2) the southern collections located on the east of the Phuket mountain range located between approximately 6.5 degrees and 11.5 degrees north latitude. AMOVA revealed significant genetic differentiation between northern and middle southern and southern populations. The middle southern population was moderately differentiated from the southern population. Furthermore, gene flow was restricted between proximal collections located on different sides of the Phuket mountain range. Collections separated by 50 km exhibited restriction of gene flow when separated by geographic barriers, whereas greater gene flow was evident among collections 650 km apart but without geographic barriers. PMID:17014059

  11. Mitochondrial and Allozyme Genetics of Incipient Speciation in a Landlocked Population of Galaxias Truttaceus (Pisces: Galaxiidae)

    PubMed Central

    Ovenden, J. R.; White, RWG.

    1990-01-01

    Galaxias truttaceus is found in coastal rivers and streams in south-eastern Australia. It spawns at the head of estuaries in autumn and the larvae spend 3 months of winter at sea before returning to fresh water. In Tasmania there are landlocked populations of G. truttaceus in a cluster of geologically young lakes on the recently glaciated Central Plateau. These populations have no marine larval stage and spawn in the lakes in spring. Speciation due to land locking is thought to be a frequent occurrence within Galaxias. To investigate the nature of the speciation event which may be occurring within lake populations of G. truttaceus we studied the mitochondrial DNA (mtDNA) and allozyme diversity of both lake and stream populations. Using the presence or absence of restriction sites recognized by 13 six-base restriction endonucleases, we found 58 mtDNA haplotypes among 150 fish collected from 13 Tasmanian and one south-east Australian mainland stream populations. The most parsimonious network relating the haplotypes by site loss or gain was starlike in shape. We argue that this arrangement is best explained by selection upon slightly beneficial mutations within the mitochondrial genome. Gene diversity analysis under Wright's island model showed that the populations in each drainage were not genetically subdivided. Only two of these stream haplotypes were found among the 66 fish analyzed from four lake populations. Despite the extreme lack of mtDNA diversity in lake populations, the observed nuclear DNA heterozygosity of 40 lake fish (0.10355) was only slightly less than that of 82 stream fish (0.11635). In the short time (3000-7000 years) that the lake fish have been landlocked, random genetic drift in a finite, stable-sized population was probably not responsible for the lack of mtDNA diversity in the lake populations. We infer the lake populations have probably experienced at least one, severe, but transitory bottleneck possibly induced by natural selection for life-history characters essential for survival in the lacustrine habitat. If speciation is occurring in the landlocked populations of G. truttaceus, then it may be driven by genetic transilience. PMID:2155855

  12. Influence of substrate and relative humidity on the efficacy of three entomopathogenic fungi for the hide beetle, Dermestes maculatus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dermestes maculatus is carrion feeder that is also a pest of poultry houses, museums, silkworm culture, and many stored foods. The Hypocreales, Beauveria bassiana, Metarhizium anisopliae, and Isaria fumosorosea, were tested for efficacy against D. maculatus larvae on concrete, plastic, leather, and ...

  13. Talisia esculenta lectin and larval development of Callosobruchus maculatus and Zabrotes subfasciatus (Coleoptera: Bruchidae).

    PubMed

    Macedo, Maria Ligia R; das Graças Machado Freire, Maria; Novello, José Camillo; Marangoni, Sérgio

    2002-06-01

    Bruchid larvae cause major losses in grain legume crops throughout the world. Some bruchid species, such as the cowpea weevil and the Mexican bean weevil, are pests that damage stored seeds. Plant lectins have been implicated as antibiosis factors against insects, particularly the cowpea weevil, Callosobruchus maculatus. Talisia esculenta lectin (TEL) was tested for anti-insect activity against C. maculatus and Zabrotes subfasciatus larvae. TEL produced ca. 90% mortality to these bruchids when incorporated in an artificial diet at a level of 2% (w/w). The LD(50) and ED(50) for TEL was ca. 1% (w/w) for both insects. TEL was not digested by midgut preparations of C. maculatus and Z. subfasciatus. The transformation of the genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops. PMID:12049788

  14. Why Do Female Callosobruchus maculatus Kick Their Mates?

    PubMed Central

    van Lieshout, Emile; McNamara, Kathryn B.; Simmons, Leigh W.

    2014-01-01

    Sexual conflict is now recognised as an important driver of sexual trait evolution. However, due to their variable outcomes and effects on other fitness components, the detection of sexual conflicts on individual traits can be complicated. This difficulty is exemplified in the beetle Callosobruchus maculatus, where longer matings increase the size of nutritious ejaculates but simultaneously reduce female future receptivity. While previous studies show that females gain direct benefits from extended mating duration, females show conspicuous copulatory kicking behaviour, apparently to dislodge mating males prematurely. We explore the potential for sexual conflict by comparing several fitness components and remating propensity in pairs of full sibling females where each female mated with a male from an unrelated pair of full sibling males. For one female, matings were terminated at the onset of kicking, whereas the other’s matings remained uninterrupted. While fecundity (number of eggs) was similar between treatments, uninterrupted matings enhanced adult offspring numbers and fractionally also longevity. However, females whose matings were interrupted at the onset of kicking exhibited an increased propensity to remate. Since polyandry can benefit female fitness in this species, we argue that kicking, rather than being maladaptive, may indicate that females prefer remating over increased ejaculate size. It may thus be difficult to assess the presence of sexual conflict over contested traits such as mating duration when females face a trade off between direct benefits gained from one mating and indirect benefits from additional matings. PMID:24752530

  15. Phylogeographical population structure of tiger quolls Dasyurus maculatus (Dasyuridae: Marsupialia), an endangered carnivorous marsupial.

    PubMed

    Firestone, K B; Elphinstone, M S; Sherwin, W B; Houlden, B A

    1999-10-01

    Tiger quolls, Dasyurus maculatus, are the largest carnivorous marsupials still extant on the mainland of Australia, and occupy an important ecological niche as top predators and scavengers. Two allopatric subspecies are recognized, D.m. gracilis in north Queensland, and D.m. maculatus in the southeast of the mainland and Tasmania. D.m. gracilis is considered endangered while D.m. maculatus is listed as vulnerable to extinction; both subspecies are still in decline. Phylogeographical subdivision was examined to determine evolutionarily significant units (ESUs) and management units (MUs) among populations of tiger quolls to assist in the conservation of these taxa. Ninety-three tiger quolls from nine representative populations were sampled from throughout the species range. Six nuclear microsatellite loci and the mitochondrial DNA (mtDNA) control region (471 bp) were used to examine ESUs and MUs in this species. We demonstrated that Tasmanian tiger quolls are reciprocally monophyletic to those from the mainland using mtDNA analysis, but D.m. gracilis was not monophyletic with respect to mainland D.m. maculatus. Analysis of microsatellite loci also revealed significant differences between the Tasmanian and mainland tiger quolls, and between D.m. gracilis and mainland D.m. maculatus. These results indicate that Tasmanian and mainland tiger quolls form two distinct evolutionary units but that D.m. gracilis and mainland D.m. maculatus are different MUs within the same ESU. The two marker types used in this study revealed different male and female dispersal patterns and indicate that the most appropriate units for short-term management are local populations. A revised classification and management plan are needed for tiger quolls, particularly in relation to conservation of the Tasmanian and Queensland populations. PMID:10583825

  16. The complete mitochondrial genome of Rhinogobio typus (Teleostei, Cyprinidae, Gobioninae).

    PubMed

    Yan, Shu-Xiang; Xiong, Mei-Hua; Zhu, Bin; Tian, Hua; Liao, Xiao-Lin; Shao, Ke

    2016-01-01

    In the present study, the complete mitochondrial genome sequence of Rhinogobio typus (Teleostei, Cyprinidae, Gobioninae) was obtained using a PCR-based method. The total length of the mitochondrial genome is 16,608?bp, including 22 transfer RNA genes, 2 ribosomal RNA genes, 13 protein-coding genes, and a non-coding control region (D-loop), which is similar to that observed in many other reported fishes. The overall-based composition is 31.3% A, 26.6% T, 15.9% G and 26.2% C, with high A?+?T content (57.9%). These results will provide a useful tool for species identification, evolutionary and population genetic studies of R. typus and its related species. PMID:24779592

  17. Modification of microridge pattern in teleost (Pimelodus maculatus) epidermal cells induced by NaCl.

    PubMed

    Ferri, S

    1983-01-01

    When NaCl is added to the aqueous environment, the fingerprint-like pattern showed by microridges of epidermal superficial cells of the teleost Pimelodus maculatus is modified. This modification probably occurs consequently the rearrangement of cytoplasmic filaments. PMID:6884732

  18. Reproduction and embryogenesis of the mandi-amarelo catfish, Pimelodus maculatus (Pisces, Pimelodidae), in captivity.

    PubMed

    Arantes, F P; Borato, F L; Sato, Y; Rizzo, E; Bazzoli, N

    2013-02-01

    To study reproduction and embryogenesis, Pimelodus maculatus specimens were kept in captivity and captured bimonthly during 1 year. Gonads samples (211 specimens) were collected and submitted to routine histological techniques. Pimelodus maculatus prepared to reproduce when water temperature was high, and even reached advanced maturation but did not spawn in captivity. Spent fish gonads were not documented, and atretic follicles were frequent (60%) in late maturation females. When then submitted to hypophysation, 70% of the females responded positively to hormonal treatment. Oocyte extrusion occurred 8 h after a second hormonal injection at 26C. The fertilisation rate was 65.1 9.2% at 24C. Recently spawned oocytes of P. maculatus were spherical, non-adhesive, yellow in colour, with an average diameter of 1113.92 37.02 ?m and covered by a thick gelatinous layer. Blastopore closure occurred 7 h and 30 min after fertilisation. Embryonic development was completed within 18 h after fertilisation. The results of this work provide important knowledge for the handling and cultivation of not only P. maculatus, but other species of potential value for fish culture. PMID:22612443

  19. First report of the characterization of the pathophysiological mechanisms caused by the freshwater catfish Pimelodus maculatus (order: Siluriformes).

    PubMed

    Sarmiento, Beatriz Elena; Rangel, Marisa; Gonçalves, Jacqueline Coimbra; Pereira, Lilibete; Rego, Solange; Campos, Leandro Ambrósio; Haddad, Vidal; Mortari, Márcia Renata; Schwartz, Elisabeth F

    2015-07-01

    Injuries caused by aquatic animals in Brazil in most cases are provoked by marine and freshwater catfish. Pimelodus maculatus is a freshwater catfish very common in Brazilian basins that causes frequent accidents mainly amongst fishermen, and whose venom characteristics and pathological mechanisms of the venom are poorly known. In the present study for the first time, we have characterized the main pathophysiological mechanisms associated with the clinical manifestation (pain, local inflammation and edema) of the envenomations caused by P. maculatus crude venom. It was estimated that the crude venom of one P. maculatus stinger contains approximately 100 μg of protein, likely the quantity involved in the envenomation. P. maculatus crude venom induced marked nociceptive and edematogenic effects and caused vascular permeability alterations at doses from 30 to 100 μg/animal. Additionally, P. maculatus crude venom caused a decrease in the contraction force in in situ frog heart, did not cause hemorrhage or alterations in clotting times (prothrombin time and activated partial thromboplastin time), but induced significant changes in the levels of CK and its isoenzyme CK-MB in mice. In the present work, we present a correlation between the effects obtained experimentally and the main symptoms observed in the human accidents provoked by P. maculatus. PMID:25911957

  20. Lima bean (Phaseolus lunatus) seed coat phaseolin is detrimental to the cowpea weevil (Callosobruchus maculatus).

    PubMed

    Moraes, R A; Sales, M P; Pinto, M S; Silva, L B; Oliveira, A E; Machado, O L; Fernandes, K V; Xavier-Filho, J

    2000-02-01

    The presence of phaseolin (a vicilin-like 7S storage globulin) peptides in the seed coat of the legume Phaseolus lunatus L. (lima bean) was demonstrated by N-terminal amino acid sequencing. Utilizing an artificial seed system assay we showed that phaseolin, isolated from both cotyledon and testa tissues of P. lunatus, is detrimental to the nonhost bruchid Callosobruchus maculatus (F) (cowpea weevil) with ED50 of 1.7 and 3.5%, respectively. The level of phaseolin in the seed coat (16.7%) was found to be sufficient to deter larval development of this bruchid. The expression of a C. maculatus-detrimental protein in the testa of nonhost seeds suggests that the protein may have played a significant role in the evolutionary adaptation of bruchids to legume seeds. PMID:10657058

  1. Modification of postmortem wounds by Dermestes maculatus (Coleoptera: Dermestidae) activity: A preliminary study.

    PubMed

    Zanetti, Noelia I; Ferrero, Adriana A; Centeno, Néstor D

    2015-11-01

    The purpose of this analysis was to evaluate the effects of insect activity on hacking trauma which was inflicted with a small cleaver and a razor blade under controlled conditions. Three pig hooves were each subjected to a blow with a small cleaver and a cut with a razor blade prior to insect exposure. We used Dermestes maculatus DeGeer 1774 species. These beetles made principally depressions and destruction on both wounds, and bites were observed on the edges of the wounds. As time passed and insects fed and refuge, chop marks were deformed and disappeared, taking this less than a month. Thus, D. maculatus could mask postmortem wounds and probably premortem wounds, and so the cause of death. PMID:26352289

  2. Electron microscope observations on the cytoplasmic granules of a freshwater teleost (Pimelodus maculatus) leucocyte.

    PubMed

    Ferri, S; Hernandez Blazquez, F J

    1987-01-01

    In the present study, a hitherto undescribed granule type in the leucocytes of the freshwater teleost Pimelodus maculatus is reported. This membrane bounded elliptic granule contains straight tubules measuring from 8 to 10 nm in diameter. Almost all granules present 1 or 2 electron dense inclusions more often than not with a geometrical form. A comparison with the granules found in Prochilodus scrofa leucocytes is made. PMID:3631529

  3. Ultrastructure of the epidermal cells of the teleost Pimelodus maculatus Lacpde, 1803 (pisces).

    PubMed

    Ferri, S; Stipp, A C; Sesso, A; Correa, H

    1977-01-01

    By means of electronmicroscope technique were studied the cell types in the epidermis of the teleost Pimelodus maculatus LACEPEDE. The varied cells were described after their morphological aspect. The behaviour of the plasma membrane and the cytoplasmatic components, especially the microfilaments and the rough endoplasmatic reticulum, were discussed in the functionally manner of this cells. The relationship of the cell types to the mitotic cell cycle gave some interesting references. PMID:900513

  4. Electron microscopic study of lymphocytes in a freshwater teleost (Pimelodus maculatus) epidermis.

    PubMed

    Ferri, S

    1983-01-01

    Small lymphocytes were identified in a freshwater teleost (Pimelodus maculatus) epidermis at the ultrastructural level. Although they were the most abundant, the medium and the large lymphocytes were also present. They were found at all levels of the epidermis, specially in small spaces between the cells of the basal layer. They appeared in contact only with filament-containing cells. Intercellular junctions, however, were never observed. They were negative to the histochemical test used to detect the present of acid phosphatase. PMID:6650847

  5. UVB-induced gene expression in the skin of Xiphophorus maculatus Jp 163 B☆

    PubMed Central

    Yang, Kuan; Boswell, Mikki; Walter, Dylan J.; Downs, Kevin P.; Gaston-Pravia, Kimberly; Garcia, Tzintzuni; Shen, Yingjia; Mitchell, David L.; Walter, Ronald B.

    2014-01-01

    Xiphophorus fish and interspecies hybrids represent long-standing models to study the genetics underlying spontaneous and induced tumorigenesis. The recent release of the Xiphophorus maculatus genome sequence will allow global genetic regulation studies of genes involved in the inherited susceptibility to UVB-induced melanoma within select backcross hybrids. As a first step toward this goal, we report results of an RNA-Seq approach to identify genes and pathways showing modulated transcription within the skin of X. maculatus Jp 163 B upon UVB exposure. X. maculatus Jp 163 B were exposed to various doses of UVB followed by RNA-Seq analysis at each dose to investigate overall gene expression in each sample. A total of 357 genes with a minimum expression change of 4-fold (p-adj < 0.05) were identified as responsive to UVB. The molecular genetic response of Xiphophorus skin to UVB exposure permitted assessment of; (1) the basal expression level of each transcript for each skin sample, (2) the changes in expression levels for each gene in the transcriptome upon exposure to increasing doses of UVB, and (3) clusters of genes that exhibit similar patterns of change in expression upon UVB exposure. These data provide a foundation for understanding the molecular genetic response of fish skin to UVB exposure. PMID:24556253

  6. Performance of Uscana mukerjii (Mani) for the control of Callosobruchus maculatus (Fab.) and allied bruchid species.

    PubMed

    Sood, Seema; Pajni, H R; Tewari, P K

    2003-08-01

    Investigations have been carried out on the relative preference of U. mukerjii to four common species viz., C. maculatus, C. analis, C. chinensis and Zabrotes subfasciatus of store bruchids. Results show correspondence between the acceptance/contact ratio and the total number of eggs laid by the parasitoid for Callosobruchus species. U. mukerjii shows maximum preference on C. maculatus followed by C. analis, C. chinensis and Z. subfasciatus in the decreasing order. Z. subfasciatus has been the least preferred host having 2-3% parasitization in choice situation. Percentage emergence of the adults and females differ insignificantly from each other in Callosobruchus species. In no choice experiments, U. mukerjii laid sufficient number of eggs in the eggs of C. chinensis and Z. subfasciatus but less number of eggs in a choice situation due to competition with the preferred host. As is evident, U. mukerjii gives the first preference to primary host C. maculatus. Moreover, the congeneric species i.e C. analis and C. chinensis are given more preference than Z. subfasciatus. PMID:15248494

  7. Molecular Phylogeny and Biogeography of Percocypris (Cyprinidae, Teleostei)

    PubMed Central

    Wang, Mo; Yang, Jun-Xing; Chen, Xiao-Yong

    2013-01-01

    Fierce predatory freshwater fishes, the species of Percocypris (Cyprinidae, Teleostei) inhabit large rivers or lakes, and have a specific distribution pattern. Only a single species or subspecies occurs in each large-scale drainage basin of the Southeastern Tibetan Plateau. In this study, the molecular phylogenetic relationships for all but one of the described subspecies/species of Percocypris were investigated based on three mitochondrial genes (16S; COI; Cyt b) and one nuclear marker (Rag2). The results of Maximum Likelihood and Bayesian Inference analyses show that Percocypris is a strongly supported monophyletic group and that it is the sister group of Schizothorax. Combined with analyses of morphological characters, our results suggest that Percocypris needs to be reclassified, and we propose that six species be recognized, with corresponding distributions in five main drainages (including one lake). In addition, based on the results of the estimation of divergence times and ancestral drainages, we hypothesize that Percocypris likely originated in the early Miocene from a paleo-connected drainage system containing the contemporary main drainages of the Southeastern Tibetan Plateau. This study suggests that vicariance (due to the uplift of the Tibetan Plateau modifying the large-scale morphologies of drainage basins in the Southeastern Tibetan Plateau) has played an important role in the speciation of the genus. Furthermore, external morphological characters (such as the length of the fins) and an internal trait (the position of pterygiophore) appear to be correlated with different habitats in rivers and the lake. PMID:23750199

  8. Preliminary Results on Evaluation of Chickpea, Cicer arietinum, Genotypes for Resistance to the Pulse Beetle, Callosobruchus maculatus

    PubMed Central

    Erle, F.; Ceylan, F.; Erdemir, T.; Toker, C.

    2009-01-01

    The chickpea, Cicer arietinum L. (Fabales: Fabaceae), seeds are vulnerable, both in the field and in storage, to attack by seed-beetles. Beetles of the genus Callosobruchus are major storage pests of chickpea crops and cause considerable economic losses. In the present study, a total of 11 chickpea genotypes including five kabuli (Mexican white, Diyar, CA 2969, ILC 8617 and ACC 245) and six desi chickpeas (ICC 1069, ICC 12422, ICC 14336, ICC 4957, ICC 4969 and ICC 7509) were evaluated for resistance to the pulse beetle Callosobruchus maculatus F. (Coleoptera: Bruchidae). Resistance was evaluated by measuring percent damage to seeds. Damage to seeds by C. maculatus was manifested by the round exit holes with the flap of seed coat made by emerging adults. Of the 11 genotypes tested, only one (ICC 4969) exhibited a complete resistance to C. maculatus in both free-choice and no-choice tests; no seed damage was found over the test period. In general, the desi chickpeas were more resistant to C. maculatus than the kabuli chickpeas. Among the tested chickpea genotypes, only ICC 4969 can be used as a source of C. maculatus resistance in breeding programmes that could then be grown in organic cultivation free from pesticides. PMID:20050777

  9. Biochemical characterization of the alpha-amylase inhibitor in mungbeans and its application in inhibiting the growth of Callosobruchus maculatus.

    PubMed

    Wisessing, Anussorn; Engkagul, Arunee; Wongpiyasatid, Arunee; Choowongkomon, Kiattawee

    2010-02-24

    The insect Callosobruchus maculatus causes considerable damage to harvested mungbean seeds every year, which leads to commercial losses. However, recent studies have revealed that mungbean seeds contain alpha-amylase inhibitors that can inhibit the protein C. maculatus, preventing growth and development of the insect larvae in the seed, thus preventing further damage. For this reason, the use of alpha-amylase inhibitors to interfere with the pest's digestion process has become an interesting alternative biocontrolling agent. In this study, we have isolated and purified the alpha-amylase inhibitor from mungbean seeds (KPS1) using ammonium sulfate precipitation, gel filtration chromatography and reversed phase HPLC. We found that the alpha-amylase inhibitor, isolated as a monomer, had a molecular weight of 27 kDa. The alpha-amylase inhibitor was purified 750-fold with a final yield of 0.4 mg of protein per 30 g of mungbean seeds. Its specific activity was determined at 14.5 U (mg of protein)(-1). Interestingly, we found that the isolated alpha-amylase inhibitor inhibits C. maculatus alpha-amylase but not human salivary alpha-amylase. After preincubation of the enzyme with the inhibitor, the mungbean alpha-amylase inhibitor inhibited C. maculatus alpha-amylase activity by decreasing V(max) while increasing the K(m) constant, indicating that the mungbean alpha-amylase is a mix noncompetitive inhibitor. The in vivo effect of alpha-amylase inhibitor on the mortality of C. maculatus shows that the alpha-amylase inhibitor acts on C. maculatus during the development stage, by reducing carbohydrate digestion necessary for growth and development, rather than during the end laying/hatching stage. Our results suggest that mungbean alpha-amylase inhibitor could be a useful future biocontrolling agent. PMID:20099823

  10. Sex-specific molecular genetic response to UVB exposure in Xiphophorus maculatus skin.

    PubMed

    Boswell, William; Boswell, Mikki; Titus, James; Savage, Markita; Lu, Yuan; Shen, Jianjun; Walter, Ronald B

    2015-12-01

    In both Xiphophorus fishes and humans, males are reported to have a higher incidence of melanoma than females. To better understand sex-specific differences in the molecular genetic response to UVB, we performed RNA-Seq experiments in skin of female and male Xiphophorus maculatus Jp 163 B following UVB doses of 8 or 16kJ/m(2) exposure. Male X. maculatus differentially express a significantly larger number of transcripts following exposure to 16kJ/m(2) UVB (1293 genes) compared to 8kJ/m(2) UVB (324 genes). Female skin showed differential gene expression in a larger number of transcripts following 8kJ/m(2) UVB (765) than did males; however, both females and males showed similar numbers of differentially expressed genes at 16kJ/m(2) UVB (1167 and1293, respectively). Although most modulated transcripts after UVB exposure represented the same dominant pathways in both females and males (e.g., DNA repair, circadian rhythm, and fatty acid biosynthesis), we identified genes in several pathways that exhibited opposite modulation in female vs. male skin (e.g., synaptic development, cell differentiation, wound healing, and glucose metabolism). The oppositely modulated genes appear related through uncoupling protein 3 (UCP3) that is involved with the regulation of fatty acid oxidation and serves to balance glucose and lipid metabolism. Overall, these results identify gender-specific differences in UVB-induced genetic profiles in the skin of females and males and show female and male X. maculatus respond to UVB differently through pathways involved in reactive oxygen species, wound healing, and energy homeostasis. PMID:26256120

  11. Differences in midgut serine proteinases from larvae of the bruchid beetles Callosobruchus maculatus and Zabrotes subfasciatus.

    PubMed

    Silva, C P; Terra, W R; Lima, R M

    2001-05-01

    Proteinase activities in the larval midguts of the bruchids Callosobruchus maculatus and Zabrotes subfasciatus were investigated. Both midgut homogenates showed a slightly acidic to neutral pH optima for the hydrolysis of fluorogenic substrates. Proteolysis of epsilon-aminocaproil-Leu-Cys(SBzl)-MCA was totally inhibited by the cysteine proteinase inhibitors E-64 and leupeptin, and was activated by 1.5 mM DTT in both insects, while hydrolysis of the substrate Z-ArgArg-MCA was inhibited by aprotinin and E-64, which suggests that it is being hydrolysed by serine and cysteine proteinases. Gel assays showed that the proteolytic activity in larval midgut of C. maculatus was due to five major cysteine proteinases. However, based on the pattern of E-64 and aprotinin inhibition, proteolytic activity in larval midgut of Z. subfasciatus was not due only to cysteine proteinases. Fractionation of the larval midgut homogenates of both bruchids through ion-exchange chromatography (DEAE-Sepharose) revealed two peaks of activity against Z-ArgArg-MCA for both bruchid species. The fractions from C. maculatus have characteristics of cysteine proteinases, while Z. subfasciatus has one non-retained peak of activity containing cysteine proteinases and another eluted in a gradient of 250-350 mM NaCl. The proteolytic activity of the retained peak is higher at pH 8.8 than at pH 6.0 and corresponds with a single peak that is active against N-p-tosyl-GlyGlyArg-MCA, and sensitive to 250 microM aprotinin (90% inhibition). The peak contains a serine proteinase which hydrolyzes alpha-amylase inhibitor 1 from the common bean (Phaseolus vulgaris). Arch. PMID:11317332

  12. Insecticidal Activity and Chemical Composition of the Morinda lucida Essential Oil against Pulse Beetle Callosobruchus maculatus

    PubMed Central

    Owolabi, Moses S.; Ogundajo, Akintayo L.; Ogunwande, Isiaka A.; Yusuff, Olaniyi K.; Flores-Fernandez, Karen Isabel; Flores-Fernandez, Jose Miguel

    2014-01-01

    Insecticidal activity of essential oil extracted from Morinda lucida was tested on pulse beetle Callosobruchus maculatus, which is a pest that causes serious damage to several pulses. The insecticidal activity was compared with two pesticides, Phostoxin and Primo-ban-20. 120 mixed sex adult C. maculatus were introduced, along with 30 g of cowpeas. Four concentrations (0.40, 0.20, 0.10, and 0.05 μg/mL) of the M. lucida essential oil, Phostoxin, and Primo-ban-20 were tested. Essential oil chemical composition was analyzed by GC-MS. M. lucida essential oil showed a high toxicological effect, producing 100% mortality after 72 hours at a dose of 0.20 μg/mL. M. lucida essential oil had a potent insecticidal activity (LC90 = 0.629 μg/mL) compared to both pesticides, Phostoxin (LC90 = 0.652 μg/mL) and Primo-ban-20 (LC90 = 0.726 μg/mL), at 24 h. The main compounds of the essential oil were the oxygenated monoterpenoids, 1,8-cineole (43.4%), and α-terpinyl acetate (14.5%), and the monoterpene hydrocarbons, mostly sabinene (8.2%) and β-pinene (4.0%). Results clearly indicate that M. lucida essential oil can be used as an effective alternative for pulse beetle C. maculatus control, and it could be tested against other pulse beetles affecting Asia and Africa and throughout the world, thereby reducing use of synthetic pesticides. PMID:25143991

  13. Analyses of nucleolus organizer regions and heterochromatin of Pimelodus maculatus (Pisces, Pimelodidae).

    PubMed

    Swara, A C; Giuliano-Caetano, L; Dias, A L

    2000-01-01

    Eighteen specimens of Pimelodus maculatus collected from Tibagi River (Sertaneja, PR, Brazil) were analyzed cytogenetically. The diploid number of 56 chromosomes was observed and karyotype was 20 M + 20 SM + 10 ST + 6 A with fundamental number (FN) of 106. Results of analyses from the nucleolus organizer regions (NORs), obtained by AgNO3, CMA3 and C-band staining showed marking in a terminal position on the long arm of a pair of subtelocentric chromosomes. The restriction enzyme AluI produced a linear differentiation similar to C-banding. PMID:11519880

  14. Isolation and characterization of microsatellite loci in Pimelodus maculatus (Siluriformes: Pimelodidae).

    PubMed

    Paiva, Ana Luiza B; Kalapothakis, Evanguedes

    2008-09-01

    To evaluate genetic variability in Pimelodus maculatus, a small migratory catfish common in South America, we isolated and characterized several microsatellite markers from individuals collected from a population in the River Grande (Brazil). A total of 11 loci were obtained and analyzed. All the loci were polymorphic, with the number of alleles ranging from three to 27 per locus. Observed and expected heterozygosities ranged from 0.5 to 0.89 and from 0.53 to 0.95, respectively. These polymorphic markers can be used as effective tools to study the genetic structure in populations of this species. PMID:21585977

  15. Fine structure of a freshwater teleost (Pimelodus maculatus) hepatocytes revealed by ultrathin sections.

    PubMed

    Bonates, A B; Ferri, S

    1980-01-01

    The hepatocytes of Pimelodus maculatus studied in thin sections revealed: 1. 3 physiological surfaces: a) in content with the Disse's space; b) in contact with neighboring hepatocytes; and c) showing grooves that delimit bile canaliculi; 2. bile canaliculi presenting, sometimes, intracellular diverticula; 3. junctional complexes joining hepatocytes close to the bile canaliculi; 4. gap junctions in great number; 5. a characteristic feature of the RER; 6. a commonly close relationship between mitochondria and RER; 7. Golgi complexes near the bile canaliculi and in the perinuclear area; 8. smooth endoplasmic reticulum, lysosomes, glycogen and lipids in small amounts. PMID:7212288

  16. Isolation and characterization of an anti-insect β-toxin from the venom of the scorpion Isometrus maculatus.

    PubMed

    Kawachi, Tomoyuki; Miyashita, Masahiro; Nakagawa, Yoshiaki; Miyagawa, Hisashi

    2013-01-01

    Im-3 was isolated from the venom of the scorpion Isometrus maculatus through several steps of HPLC fractionation based on the insect paralytic activity. Injecting Im-3 into crickets induced paralysis, but no toxicity was apparent in mice after an intracerebroventricular injection. Im-3 shares sequence similarity to scorpion β-toxins that specifically affect insect sodium channels. PMID:23291760

  17. The structure of the monogenean community on the gills of Pimelodus maculatus in Ro de la Plata (Argentina).

    PubMed

    Gutirrez, P A; Martorelli, S R

    1999-08-01

    The Monogenea fauna was studied from the gills of the catfish Pimelodus maculatus. Fish were caught from Ro de la Plata, in Buenos Aires harbour (Argentina). Five species of Monogenea were found. The structure of the monogenean community was analysed at the component and infracommunity level. The nature of the monogenean community, its possible interactivity, seasonal variation and predictability are also discussed. PMID:10466125

  18. Lethal and Sublethal Effects of Essential Oils from Eucalyptus camaldulensis and Heracleum persicum Against the Adults of Callosobruchus Maculatus

    PubMed Central

    Izakmehri, Khadijeh; Saber, Moosa; Mehrvar, Ali; Hassanpouraghdam, Mohammad Bagher; Vojoudi, Samad

    2013-01-01

    The cowpea weevil, Callosobruchus maculatus F. (Coleoptera: Bruchidae), is an important pest of stored cowpea, Vigna ungiculata (L.) Walpers (Fabales: Fabaceae), with ample distribution in tropical and subtropical regions. Many plant essential oils have a broad-spectrum activity against pest insects, and these oils traditionally have been used in the protection of stored products. In this study, the lethal and sublethal effects of essential oils from Eucalyptus camaldulensis Dehnh. (Myrtales: Myrtaceae) and Heracleum persicum Desf. (Apiales: Apiaceae) were evaluated on the adults of C. maculatus at 26 1 C, 70 5% RH, and a photoperiod of 16:8 L:D. The LC50 values of E. camaldulensis and H. persicum were 56.7 and 219.4 L/L air after 12 hr and 26.1 and 136.4 L/L air after 24 hr of exposure, respectively. The LT50 values of E. camaldulensis and H.persicum were 6.3 and 10.9 hr, respectively. The results showed that low lethal concentration (LC20) of essential oils negatively affected the longevity, fecundity, and fertility of female adults. The sex ratio of C. maculatus offspring was not significantly affected by essential oils. Therefore, these essential oils can be suggested for controlling C. maculatus in storage systems. The introduction of essential oils into storage systems could potentially decrease seed losses. PMID:24773362

  19. Lethal and sublethal effects of essential oils from Eucalyptus camaldulensis and Heracleum persicum against the adults of Callosobruchus maculatus.

    PubMed

    Izakmehri, Khadijeh; Saber, Moosa; Mehrvar, Ali; Hassanpouraghdam, Mohammad Bagher; Vojoudi, Samad

    2013-01-01

    The cowpea weevil, Callosobruchus maculatus F. (Coleoptera: Bruchidae), is an important pest of stored cowpea, Vigna ungiculata (L.) Walpers (Fabales: Fabaceae), with ample distribution in tropical and subtropical regions. Many plant essential oils have a broad-spectrum activity against pest insects, and these oils traditionally have been used in the protection of stored products. In this study, the lethal and sublethal effects of essential oils from Eucalyptus camaldulensis Dehnh. (Myrtales: Myrtaceae) and Heracleum persicum Desf. (Apiales: Apiaceae) were evaluated on the adults of C. maculatus at 26 1 C, 70 5% RH, and a photoperiod of 16:8 L:D. The LC50 values of E. camaldulensis and H. persicum were 56.7 and 219.4 L/L air after 12 hr and 26.1 and 136.4 L/L air after 24 hr of exposure, respectively. The LT50 values of E. camaldulensis and H.persicum were 6.3 and 10.9 hr, respectively. The results showed that low lethal concentration (LC20) of essential oils negatively affected the longevity, fecundity, and fertility of female adults. The sex ratio of C. maculatus offspring was not significantly affected by essential oils. Therefore, these essential oils can be suggested for controlling C. maculatus in storage systems. The introduction of essential oils into storage systems could potentially decrease seed losses. PMID:24773362

  20. Condition dependence of male and female genital structures in the seed beetle Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Cayetano, L; Bonduriansky, R

    2015-07-01

    Theory predicts that costly secondary sexual traits will evolve heightened condition dependence, and many studies have reported strong condition dependence of signal and weapon traits in a variety of species. However, although genital structures often play key roles in intersexual interactions and appear to be subject to sexual or sexually antagonistic selection, few studies have examined the condition dependence of genital structures, especially in both sexes simultaneously. We investigated the responses of male and female genital structures to manipulation of larval diet quality (new versus once-used mung beans) in the bruchid seed beetle Callosobruchus maculatus. We quantified effects on mean relative size and static allometry of the male aedeagus, aedeagal spines, flap and paramere and the female reproductive tract and bursal spines. None of the male traits showed a significant effect of diet quality. In females, we found that longer bursal spines (relative to body size) were expressed on low-quality diet. Although the function of bursal spines is poorly understood, we suggest that greater bursal spine length in low-condition females may represent a sexually antagonistic adaptation. Overall, we found no evidence that genital traits in C. maculatus are expressed to a greater extent when nutrients are more abundant. This suggests that, even though some genital traits appear to function as secondary sexual traits, genital traits do not exhibit heightened condition dependence in this species. We discuss possible reasons for this finding. PMID:26077617

  1. New morphological data on Cucullanus pinnai pinnai (Nematoda) parasitizing Pimelodus maculatus (Pimelodidae) in southeastern Brazil.

    PubMed

    Vieira, Vivian Suane de Freitas; Vieira, Fabiano Matos; Luque, Jos Luis

    2015-01-01

    This paper describes the morphology of Cucullanus pinnai pinnai parasitizing Pimelodus maculatus in the Guandu River, Brazil, based on differential interference contrast (DIC) microscopy and scanning electron microscopy (SEM), providing new morphological data about this species of parasite. Nematodes were collected between May and October 2012 from specimens of Pimelodus maculatus in the Guandu River (2248'2"S, 4337'35"W), in the state of Rio de Janeiro, Brazil. Some characteristics of specimens of Cucullanus in this study fall within the range of morphological variations of previously studied C. pinnai pinnai. Most of the specimens studied here had excretory pore and deirids located at the posterior end of the oesophagus, a feature not recorded in previous studies of this species. In addition, the size of the gubernaculum was larger than the other specimens previously studied. The SEM and DIC analyses of C. pinnai revealed several morphological details of the cephalic region and the tail papillae. With regard to the polymorphism of C. pinnai, morphological and genetic studies of this cucullanid nematode are needed, involving large numbers of host species and a wide geographical distribution. PMID:26154955

  2. Female mating receptivity after injection of male-derived extracts in Callosobruchus maculatus.

    PubMed

    Yamane, Takashi; Miyatake, Takahisa; Kimura, Yoshinobu

    2008-12-01

    The effects of male-derived extracts on female receptivity were investigated in Callosobruchus maculatus (Coleoptera: Bruchidae). Injection of aqueous extracts of the male reproductive tract into the abdomen of females reduced receptivity. Aqueous extracts of male reproductive tracts were divided to three molecular weight (MW) fractions by ultrafiltration: Fractions: (I) MW<3 kDa, (II) 3-14 kDa, and (III)>14 kDa. Fraction II reduced female receptivity from 3h after injection, and Fraction III reduced female receptivity from 2 days after injection. On the other hand, no effect on receptivity was found for Fraction I. Furthermore, male reproductive tract organs were divided into accessory gland, testis, and seminal vesicle including the ejaculatory duct. Aqueous extracts of the seminal vesicle reduced receptivity of females immediately following injection, while aqueous extracts of the accessory gland reduced receptivity at the second day. The results suggest that the components of Fraction II existed in the seminal vesicle, and those of Fraction III in the accessory gland. The results of the present and the previous studies in Callosobruchus chinensis, a species closely related to C. maculatus, were compared and are discussed from the viewpoint of the significance of ejaculation in the two species. PMID:18831977

  3. Sex allocation and interactions between relatives in the bean beetle, Callosobruchus maculatus.

    PubMed

    Reece, Sarah E; Wherry, Ruth N; Bloor, Juliette M G

    2005-11-01

    When a small number of females contribute offspring to a discrete mating group, sex allocation (Local Mate Competition: LMC) theory predicts that females should bias their offspring sex ratio towards daughters, which avoids the fitness costs of their sons competing with each other. Conversely, when a large number of females contribute offspring to a patch, they are expected to invest equally in sons and daughters. Furthermore, sex ratios of species that regularly experience variable foundress numbers are closer to those predicted by LMC theory than species that encounter less variable foundress number scenarios. Due to their patterns of resource use, female Callosobruchus maculatus are likely to experience a broad range of foundress number scenarios. We carried out three experiments to test whether female C. maculatus adjust their sex ratios in response to foundress number and two other indicators of LMC: ovipositing on pre-parasitised patches and ovipositing with sisters. We did not find any evidence of the predicted sex ratio adjustment, but we did find evidence of kin biased behaviour. PMID:16150553

  4. Presence of the storage seed protein vicilin in internal organs of larval Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Uchôa, Adriana F; DaMatta, Renato A; Retamal, Claudio A; Albuquerque-Cunha, José M; Souza, Sheila M; Samuels, Richard I; Silva, Carlos P; Xavier-Filho, José

    2006-02-01

    Variant vicilins (7S storage globulins) of cowpea seeds (Vigna unguiculata) are considered as the main resistance factor present in some African genotypes against the bruchid Callosobruchus maculatus. It has been suggested that the toxic properties of vicilins may be related to their recognition and interaction with glycoproteins and other membrane constituents along the digestive tract of the insect. However, the possibility of a systemic effect has not yet been investigated. The objective of this work was to study the fate of 7S storage globulins of V. unguiculata in several organs of larvae of the cowpea weevil C. maculatus. Results demonstrated binding of vicilins to brush border membrane vesicles, suggesting the existence of specific receptors. Vicilins were detected in the haemolymph, in the midgut, and in internal organs, such as fat body and malpighian tubules. There is evidence of accumulation of vicilins in the fat body of both larvae and adults. The absorption of vicilins and their presence in insect tissues parallels classical sequestration of secondary compounds. PMID:16288905

  5. Echoes of a distant time: effects of historical processes on contemporary genetic patterns in Galaxias platei in Patagonia.

    PubMed

    Vera-Escalona, Iván; Habit, Evelyn; Ruzzante, Daniel E

    2015-08-01

    Interpreting the genetic structure of a metapopulation as the outcome of gene flow over a variety of timescales is essential for the proper understanding of how changes in landscape affect biological connectivity. Here we contrast historical and contemporary connectivity in two metapopulations of the freshwater fish Galaxias platei in northern and southernmost Patagonia where paleolakes existed during the Holocene and Pleistocene, respectively. Contemporary gene flow was mostly high and asymmetrical in the northern system while extremely reduced in the southernmost system. Historical migration patterns were high and symmetric in the northern system and high and largely asymmetric in the southern system. Both systems showed a moderate structure with a clear pattern of isolation by distance (IBD). Effective population sizes were smaller in populations with low contemporary gene flow. An approximate Bayesian computation (ABC) approach suggests a late Holocene colonization of the lakes in the northern system and recent divergence of the populations from refugial populations from east and west of the Andes. For the southern system, the ABC approach reveals that some of the extant G. platei populations most likely derive from an ancestral population inhabiting a large Pleistocene paleolake while the rest derive from a higher-altitude lake. Our results suggest that neither historical nor contemporary processes individually fully explain the observed structure and geneflow patterns and both are necessary for a proper understanding of the factors that affect diversity and its distribution. Our study highlights the importance of a temporal perspective on connectivity to analyse the diversity of spatially complex metapopulations. PMID:26147523

  6. Intron-loss evolution of hatching enzyme genes in Teleostei

    PubMed Central

    2010-01-01

    Background Hatching enzyme, belonging to the astacin metallo-protease family, digests egg envelope at embryo hatching. Orthologous genes of the enzyme are found in all vertebrate genomes. Recently, we found that exon-intron structures of the genes were conserved among tetrapods, while the genes of teleosts frequently lost their introns. Occurrence of such intron losses in teleostean hatching enzyme genes is an uncommon evolutionary event, as most eukaryotic genes are generally known to be interrupted by introns and the intron insertion sites are conserved from species to species. Here, we report on extensive studies of the exon-intron structures of teleostean hatching enzyme genes for insight into how and why introns were lost during evolution. Results We investigated the evolutionary pathway of intron-losses in hatching enzyme genes of 27 species of Teleostei. Hatching enzyme genes of basal teleosts are of only one type, which conserves the 9-exon-8-intron structure of an assumed ancestor. On the other hand, otocephalans and euteleosts possess two types of hatching enzyme genes, suggesting a gene duplication event in the common ancestor of otocephalans and euteleosts. The duplicated genes were classified into two clades, clades I and II, based on phylogenetic analysis. In otocephalans and euteleosts, clade I genes developed a phylogeny-specific structure, such as an 8-exon-7-intron, 5-exon-4-intron, 4-exon-3-intron or intron-less structure. In contrast to the clade I genes, the structures of clade II genes were relatively stable in their configuration, and were similar to that of the ancestral genes. Expression analyses revealed that hatching enzyme genes were high-expression genes, when compared to that of housekeeping genes. When expression levels were compared between clade I and II genes, clade I genes tends to be expressed more highly than clade II genes. Conclusions Hatching enzyme genes evolved to lose their introns, and the intron-loss events occurred at the specific points of teleostean phylogeny. We propose that the high-expression hatching enzyme genes frequently lost their introns during the evolution of teleosts, while the low-expression genes maintained the exon-intron structure of the ancestral gene. PMID:20796321

  7. Control of Cowpea Weevil, Callosobruchus Maculatus (F.) (Coleoptera: Bruchidae), Using Natural Plant Products

    PubMed Central

    Tiroesele, Bamphitlhi; Thomas, Kesegofetse; Seketeme, Seipati

    2014-01-01

    A laboratory study was conducted to investigate the effects of natural products on the reproduction and damage of Callosobruchus maculatus, the cowpea weevil, on cowpea seeds at Botswana College of Agriculture in Gaborone, Botswana. The cowpea variety Blackeye was used in the study. Fifty grams of each plant product (garlic, peppermint and chilies) was added to 500 g of the cowpea seeds. Findings of this experiment revealed that chilies and garlic had negative effects on cowpea weevils for all parameters measured. Peppermint also showed significant reduction in the F1 progeny of the cowpea weevils but with less effect on weevils than garlic and chilies. The results indicate that these plant products have the potential to protect cowpea seeds from cowpea weevils damage compared to when the seeds are left or stored unprotected. They should, therefore, be included in pest management strategies for cowpea weevil in grains stored on-farm in rural tropical and subtropical regions. PMID:26463066

  8. Myxobolus absonus sp. n. (Myxozoa: Myxosporea) parasitizing pimelodus maculatus (siluriformes: Pimelodidae), a South American freshwater fish.

    PubMed

    Cellere, Eduardo F; Cordeiro, Nelson S; Adriano, Edson A

    2002-01-01

    A new myxoporean species is described from a freshwater fish in Brazil. Myxobolus absonus sp. n. was found infecting Pimelodus maculatus captured in the river Piracicaba, State of So Paulo, Brazil. Cysts were found free in the opercular cavity. The spores are large (length--15.7 +/- 1.5 microns, width--10.2 +/- 0.7 microns; mean +/- S.D.) and oval in shape, with the anterior end slightly pointed. The spore valves are relatively thin, smooth, and asymmetrical in a frontal view. The polar capsules are pyriform in shape, and unequal in size; the largest are 6.4 +/- 0.7 microns long and 3.6 +/- 0.5 microns wide, while the smallest are 4.2 +/- 0.6 microns long and 2.5 +/- 0.5 microns wide. PMID:11992152

  9. Genetic characterization of the Neotropical catfish Pimelodus maculatus (Pimelodidae, Siluriformes) in the Upper Uruguay River.

    PubMed

    Ribolli, Josiane; de Melo, Cludio Manoel Rodrigues; Zaniboni-Filho, Evoy

    2012-12-01

    Freshwater fish present unique challenges when one attempts to understand the factors that determine the structure of their populations. Habitat fragmentation is a leading cause of population decline that threatens ecosystems worldwide. In this study, we investigated the conservation status of genetic variability in the Neotropical catfish (Pimelodus maculatus). Specifically, we examined the structure and genetic diversity of this species in a region of the Upper Uruguay River fragmented by natural barriers and dams. There was no genetic structure among the four sites analyzed, indicating the existence of only one population group. A combination of environmental management and genetic monitoring should be used to minimize the impact of impoundment on panmitic populations of migratory fish species. PMID:23271936

  10. Swimming performance of the freshwater neotropical fish: Pimelodus maculatus Lacepde, 1803.

    PubMed

    Santos, H A; Pompeu, P S; Vicentini, G S; Martinez, C B

    2008-05-01

    The present study used fixed and increasing velocity tests in an experimental apparatus based on Brett's respirometer to examine prolonged and sustained speeds of the "mandi-amarelo", Pimelodus maculatus. When comparing the curves of critical speed versus total length between the mandi and the sockeye salmon Oncorhynchus nerka, it is observed that for an equal total length, the mandi presents a greater speed, probably due to water temperature differences. The sustained speed for the species was estimated in 5 lengths per second and the percentage of fatigued fish within time in a certain velocity was established. The data raised for the mandi represents an important contribution to the improvement of the handling of the species, providing guidance and criteria for designing several structures, such as fishways, fish screens and guidance systems. PMID:18660976

  11. Larval Competition Reduces Body Condition in the Female Seed Beetle, Callosobruchus maculatus

    PubMed Central

    Schade, Daynika J.; Vamosi, Steven M.

    2012-01-01

    Early body condition may be important for adult behavior and fitness, and is impacted by a number of environmental conditions and biotic interactions. Reduced fecundity of adult females exposed to larval competition may be caused by reduced body condition or shifts in relative body composition, yet these mechanisms have not been well researched. Here, body mass, body size, scaled body mass index, and two body components (water content and lean dry mass) of adult Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae: Bruchinae) females exposed to larval competition or reared alone were examined. Experimental females emerged at significantly smaller body mass and body size than control females. Additionally, scaled body mass index and water content, but not lean dry mass, were significantly reduced in experimental females. To our knowledge, these are the first results that demonstrate a potential mechanism for previously documented direct effects of competition on fecundity in female bruchine beetles. PMID:22954282

  12. Genetic characterization of the Neotropical catfish Pimelodus maculatus (Pimelodidae, Siluriformes) in the Upper Uruguay River

    PubMed Central

    Ribolli, Josiane; de Melo, Cláudio Manoel Rodrigues; Zaniboni-Filho, Evoy

    2012-01-01

    Freshwater fish present unique challenges when one attempts to understand the factors that determine the structure of their populations. Habitat fragmentation is a leading cause of population decline that threatens ecosystems worldwide. In this study, we investigated the conservation status of genetic variability in the Neotropical catfish (Pimelodus maculatus). Specifically, we examined the structure and genetic diversity of this species in a region of the Upper Uruguay River fragmented by natural barriers and dams. There was no genetic structure among the four sites analyzed, indicating the existence of only one population group. A combination of environmental management and genetic monitoring should be used to minimize the impact of impoundment on panmitic populations of migratory fish species. PMID:23271936

  13. Tibet Orbivirus, a Novel Orbivirus Species Isolated from Anopheles maculatus Mosquitoes in Tibet, China

    PubMed Central

    Zhao, Guoyan; Fu, Shihong; Wang, David; Wang, Zhiyu; Liang, Guodong

    2014-01-01

    Background The genus Orbivirus includes a number of important pathogenic viruses, including Bluetongue virus (BTV), African horse sickness virus (AHSV), and Epizootic hemorrhagic disease virus (EHDV). In this study we describe the isolation and characterization of an Orbivirus strain isolated from Anopheles maculatus mosquitoes collected in Tibet, China. Methods and Results Initial viral screening identified a viral strain (XZ0906) that caused significant cytopathic effect (CPE) in BHK-21 cells, including rounding, cell rupture, and floating. Although CPE was not observed in insect cells (C6/36), these cells supported viral replication. Polyacrylamide gel analysis revealed a genome consisting of 10 segments of double-stranded RNA (dsRNA), with a distribution pattern of 3-3-3-1. 454 high throughput sequencing of culture supernatant was used for viral identification. Complete genome sequencing was performed by Sanger sequencing in combination with 5?-RACE and 3?-RACE. Sequence analysis demonstrated that all 5?- and 3?- untranslated regions (UTRs) for each of the 10 genome segments contained a series of six highly conserved nucleotides. In addition, homology analysis and phylogenetic analysis based on amino acid sequence was completed, and all results show that virus XZ0906 was not a member of any known species or serotype of Orbivirus, indicating it to be a new species within the genus Orbivirus. Conclusions The isolated Orbivirus strain was designated Tibet Orbivirus, TIBOV to denote the location from which it was isolated. TIBOV is a novel orbivirus species which is isolated from Anopheles maculatus mosquitoes collected in Tibet, China. PMID:24533145

  14. Intra-specific variation in female remating in Callosobruchus chinensis and C. maculatus.

    PubMed

    Miyatake, Takahisa; Matsumura, Fumi

    2004-05-01

    The effects of mating duration on female remating (exp. 1) and under different male densities (exp. 2) were examined in two strains of the adzuki bean beetle, Callosobruchus chinensis and in one strain of the bruchid beetle, C. maculatus. In experiment 1, the frequency of female remating was markedly different between the two strains of C. chinensis. Females of the jC strain, reared long-term in the laboratory, did not remate after being allowed to mate freely (=monogamy), whereas females of the isC strain, recently established from the field, showed high remating frequencies (=polyandry). In both strains, the frequency of female remating increased after the duration of the first mating was deliberately shortened. The relation between mating duration and remating frequency was significantly different, however, between the two strains. In a closely related species, C. maculatus, which manifests polyandry, this relation was more similar to that of the field-derived (=isC) than to that of the laboratory-derived (=jC) strain of C. chinensis. The reasons for the inter-strain variation observed in the remating frequencies of C. chinensis are also discussed. In experiment 2, the mating duration of the three strains was compared under different male densities. Only the lab-derived strain demonstrated a significantly shorter mating duration when one female was placed together with five males than when paired with one male. The shorter mating duration (approximately 26 s) was similar to that of females allowed to remate in the monogamous strain in experiment 1. PMID:15121453

  15. Molecular genetic response of Xiphophorus maculatus-X. couchianus interspecies hybrid skin to UVB exposure.

    PubMed

    Lu, Yuan; Bowswell, Mikki; Bowswell, William; Yang, Kuan; Schartl, Manfred; Walter, Ronald B

    2015-12-01

    The phenotypic and genetic similarities between Xiphophorus and human melanoma render Xiphophorus a useful animal model for studying the genetic basis of melanoma etiology. In the Xiphophorus model, melanoma has been shown to be inducible by ultraviolet light (UVB) exposure among interspecies hybrids, but not in parental line fish similarly treated. This leads to questions of what genes are responsive to UVB exposure in the skin of the interspecies hybrids, as well as how parental alleles in hybrids may be differentially regulated and the potential roles they may play in induced melanomagenesis. To address these questions, we produced X. maculatus Jp 163 BX. couchianus (Sp-Couch) F1 hybrid fish, exposed both hybrid and parental fish to UVB, and performed gene expression profiling of the skin using RNA-Seq methodology. We characterized a group of unique UVB-responsive genes in Sp-Couch hybrid including dct, pmela, tyr, tyrp1a, slc2a11b, rab38a, rab27, tspan10, slc45a2, oca2, slc24a5, ptn and mitfa. These genes are associated with melanin production and melanocyte proliferation. They were also up-regulated in Sp-Couch hybrid, indicating that their UVB response is hybridization initiated. In the hybrid, several melanin production and pigmentation related genes, including slc45a2, tspan10, dct, slc2a11b and ptn showed either X. couchianus or X. maculatus allele specific expression. The finding that these genes exhibit allele specific expression regulatory mechanisms in Sp-Couch hybrids, but do not exhibit a corresponding UVB response in either one of the parental fishes, may suggest UVB targets and imply mechanisms regarding the susceptibility of Sp-Couch to induced melanomagenesis. PMID:26254713

  16. The seed coat of Phaseolus vulgaris interferes with the development of the cowpea weevil [Callosobruchus maculatus (F.) (Coleoptera: Bruchidae)].

    PubMed

    Silva, Luciana B; Sales, Maurício P; Oliveira, Antônia E A; Machado, Olga L T; Fernandes, Kátia V S; Xavier-Filho, José

    2004-03-01

    We have confirmed here that the seeds of the common bean (Phaseolus vulgaris, L.) do not support development of the bruchid Callosobruchus maculatus (F.), a pest of cowpea [Vigna unguiculata (L.) Walp] seeds. Analysis of the testa (seed coat) of the bean suggested that neither thickness nor the levels of compounds such as tannic acid, tannins, or HCN are important for the resistance. On the other hand, we have found that phaseolin (vicilin-like 7S storage globulin), detected in the testa by Western blotting and N-terminal amino acid sequencing, is detrimental to the development of C. maculatus. As for the case of other previously studied legume seeds (Canavalia ensiformis and Phaseolus lunatus) we suggest that the presence of vicilin-like proteins in the testa of P. vulgaris may have had a significant role in the evolutionary adaptation of bruchids to the seeds of leguminous plants. PMID:15048195

  17. Efficacy of nanostructured silica as a stored pulse protector against the infestation of bruchid beetle, Callosobruchus maculatus (Coleoptera: Bruchidae)

    NASA Astrophysics Data System (ADS)

    Arumugam, Ganesh; Velayutham, Veeramani; Shanmugavel, Sakthivelkumar; Sundaram, Janarthanan

    2016-03-01

    The treatment of hydrophobic silica nanoparticles (SNPs) with the pulse seeds of Cajanus cajan, Macrotyloma uniflorum, Vigna mungo, Vigna radiata, Cicer arietinum and Vigna unguiculata against the infestation of stored pulse beetle, Callosobruchus maculatus revealed a significant reduction in oviposition, adult emergence and seed damage potential. There was a complete retardation of growth of this beetle in the treated seeds of C. cajan. SNP-treated seeds of these six varieties of pulses revealed no effect on the growth of seeds as revealed by seed germination, growth rate of root and shoot. Similarly, the soil microflora measured in terms of colony forming units was not affected by silica nanoparticles upon its treatment with pulse seeds. The results of this study thus clearly demonstrated the useful nature of silica nanoparticles as seed protecting agent for the control of C. maculatus.

  18. Efficacy of nanostructured silica as a stored pulse protector against the infestation of bruchid beetle, Callosobruchus maculatus (Coleoptera: Bruchidae)

    NASA Astrophysics Data System (ADS)

    Arumugam, Ganesh; Velayutham, Veeramani; Shanmugavel, Sakthivelkumar; Sundaram, Janarthanan

    2015-04-01

    The treatment of hydrophobic silica nanoparticles (SNPs) with the pulse seeds of Cajanus cajan, Macrotyloma uniflorum, Vigna mungo, Vigna radiata, Cicer arietinum and Vigna unguiculata against the infestation of stored pulse beetle, Callosobruchus maculatus revealed a significant reduction in oviposition, adult emergence and seed damage potential. There was a complete retardation of growth of this beetle in the treated seeds of C. cajan. SNP-treated seeds of these six varieties of pulses revealed no effect on the growth of seeds as revealed by seed germination, growth rate of root and shoot. Similarly, the soil microflora measured in terms of colony forming units was not affected by silica nanoparticles upon its treatment with pulse seeds. The results of this study thus clearly demonstrated the useful nature of silica nanoparticles as seed protecting agent for the control of C. maculatus.

  19. Niche preferences and spatial distribution of Monogenea on the gills of Pimelodus maculatus in Ro de la Plata (Argentina).

    PubMed

    Gutirrez, P A; Martorelli, S R

    1999-08-01

    Five Monogenea species were found on the gills of the catfish Pimelodus maculatus in Ro de la Plata (Argentina). These were used for studying the preference of species on different gill-hemibranches, niche breadth and niche overlap between species. It was found that congeneric species had a generic-specific preference for certain gill-hemibranches. Niche breadth appeared to be related to the number of individuals of each species. Niche overlap between the species is discussed. PMID:10466126

  20. Scanning electron microscopy studies of antennal sensilla of bruchid beetles, Callosobruchus chinensis (L.) and Callosobruchus maculatus (F.) (Coleoptera: Bruchidae).

    PubMed

    Hu, Fei; Zhang, Guo-Na; Wang, Jin-Jun

    2009-04-01

    The bruchid beetle, Callosobruchus chinensis (L.) and C. maculatus (F.) (Coleoptera: Bruchidae), are important stored-product insects of stored legume seeds. In this study, the external morphologies of the antennal sensilla on the antennae of both female and male adults of these two species were described using scanning electron microscopy. Antennae of both species are made up of the scape, pedicel, and nine segments of flagellomeres. Antennae of female and male C. maculatus and female of C. chinensis are serrate in shape, while those of male C. chinensis are pectinate. Eight morphological sensilla types were recorded in both sexes, including Bhm bristles (BB), two types of sensilla trichoid (ST1, ST2), sensilla chaetica (SC), two types of sensilla basiconic (SB1, SB2), grooved pegs (GP), and sensilla cavity (SCa). The number of ST1 and SB1 of the male were significantly greater than those of the female of C. chinensis, and the number of ST2 and SB1 of the male were significantly more abundant than those of the female of C. maculatus. The possible functions of the above sensilla types are discussed in light of previously published literature. PMID:19101159

  1. Habitat characterization and mapping of Anopheles maculatus (Theobald) mosquito larvae in malaria endemic areas in Kuala Lipis, Pahang, Malaysia.

    PubMed

    Rohani, A; Wan Najdah, W M A; Zamree, I; Azahari, A H; Mohd Noor, I; Rahimi, H; Lee, H L

    2010-07-01

    In Peninsular Malaysia, a large proportion of malaria cases occur in the central mountainous and forested parts of the country. As part of a study to assess remote sensing data as a tool for vector mapping, we conducted entomological surveys to determine the type of mosquitoes, their characteristics and the abundance of habitats of the vector Anopheles maculatus in malaria endemic areas in Pos Senderot. An. maculatus mosquitoes were collected from 49 breeding sites in Pos Senderot. An. maculatus preferred to breed in water pockets formed on the bank of rivers and waterfalls. The most common larval habitats were shallow pools 5.0-15.0 cm deep with clear water, mud substrate and plants or floatage. The mosquito also preferred open or partially shaded habitats. Breeding habitats were generally located at 100-400 m from the nearest human settlement. Changes in breeding characteristics were also observed. Instead of breeding in slow flowing streams, most larvae bred in small water pockets along the river margin. PMID:21073056

  2. A Kunitz-type inhibitor of coleopteran proteases, isolated from Adenanthera pavonina L. seeds and its effect on Callosobruchus maculatus.

    PubMed

    Macedo, Maria Lígia Rodrigues; de Sá, Claudia Mara; Freire, Maria Das Graças Machado; Parra, José Roberto Postali

    2004-05-01

    The cowpea weevil Callosobruchus maculatus is one of the major pests of Vigna unguiculata cowpea. Digestion in the cowpea weevil is facilitated by high levels of cysteine and aspartic acid proteinases. Plants synthesize a variety of molecules, including proteinaceous proteinase inhibitors, to defend themselves against attack by insects. In this work, a trypsin inhibitor (ApTI) isolated from Adenanthera pavonina seeds showed activity against papain. The inhibition of papain by ApTI was of the noncompetitive type, with a K(i) of 1 microM. ApTI was highly effective against digestive proteinases from C. maculatus, Acanthoscelides obtectus (bean weevil), and Zabrotes subfasciatus (Mexican bean weevil) and was moderately active against midgut proteinases from the boll weevil Anthonomus grandis and the mealworm Tenebrio molitor. In C. maculates fed an artificial diet containing 0.25% and 0.5% ApTI (w/w), the latter concentration caused 50% mortality and reduced larval weight gain by approximately 40%. The action of ApTI on C. maculatus larvae may involve the inhibition of ApTI-sensitive cysteine proteinases and binding to chitin components of the peritrophic membrane (or equivalent structures) in the weevil midgut. PMID:15113152

  3. Morphological and molecular data reveal a new species of Neoechinorhynchus (Acanthocephala: Neoechinorhynchidae) from Dormitator maculatus in the Gulf of Mexico.

    PubMed

    Pinacho-Pinacho, Carlos Daniel; Sereno-Uribe, Ana L; Garca-Varela, Martn

    2014-12-01

    Neoechinorhynchus (Neoechinorhynchus) mexicoensis sp. n. is described from the intestine of Dormitator maculatus (Bloch 1792) collected in 5 coastal localities from the Gulf of Mexico. The new species is mainly distinguished from the other 33 described species of Neoechinorhynchus from the Americas associated with freshwater, marine and brackish fishes by having smaller middle and posterior hooks and possessing a small proboscis with three rows of six hooks each, apical hooks longer than other hooks and extending to the same level as the posterior hooks, 1 giant nucleus in the ventral body wall and females with eggs longer than other congeneric species. Sequences of the internal transcribed spacer (ITS) and the large subunit (LSU) of ribosomal DNA including the domain D2+D3 were used independently to corroborate the morphological distinction among the new species and other congeneric species associated with freshwater and brackish water fish from Mexico. The genetic divergence estimated among congeneric species ranged from 7.34 to 44% for ITS and from 1.65 to 32.9% for LSU. Maximum likelihood and Bayesian inference analyses with each dataset showed that the 25 specimens analyzed from 5 localities of the coast of the Gulf of Mexico parasitizing D. maculatus represent an independent clade with strong bootstrap support and posterior probabilities. The morphological evidence, plus the monophyly in the phylogenetic analyses, indicates that the acanthocephalans collected from intestine of D. maculatus from the Gulf of Mexico represent a new species, herein named N. (N.) mexicoensis sp. n. PMID:25064596

  4. Insecticidal action of Bauhinia monandra leaf lectin (BmoLL) against Anagasta kuehniella (Lepidoptera: Pyralidae), Zabrotes subfasciatus and Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Macedo, Maria Lígia Rodrigues; das Graças Machado Freire, Maria; da Silva, Maria Barbosa Reis; Coelho, Luana Cassandra Breitenbach Barroso

    2007-04-01

    Bruchid beetle larvae cause major losses in grain legume crops throughout the world. Some bruchid species, such as the cowpea weevil (Callosobruchus maculatus) and the Mexican bean weevil (Zabrotes subfasciatus), are pests that damage stored seeds. The Mediterranean flour moth (Anagasta kuehniella) is of major economic importance as a flour and grain feeder; it is often a severe pest in flour mills. Plant lectins have been implicated as antibiosis factors against insects. Bauhinia monandra leaf lectin (BmoLL) was tested for anti-insect activity against C. maculatus, Z. subfasciatus and A. kuehniella larvae. BmoLL produced ca. 50% mortality to Z. subfaciatus and C. maculatus when incorporated into an artificial diet at a level of 0.5% and 0.3% (w/w), respectively. BmoLL up to 1% did not significantly decrease the survival of A. kuehniella larvae, but produced a decrease of 40% in weight. Affinity chromatography showed that BmoLL bound to midgut proteins of the insect C. maculatus. 33 kDa subunit BmoLL was not digested by midgut preparations of these bruchids. BmoLL-fed C. maculatus larvae increased the digestion of potato starch by 25% compared with the control. The transformation of the genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops. PMID:16488638

  5. The importance of carcass volatiles as attractants for the hide beetle Dermestes maculatus (De Geer).

    PubMed

    von Hoermann, C; Ruther, J; Reibe, S; Madea, B; Ayasse, M

    2011-10-10

    A decaying cadaver emits volatile organic compounds that are used by necrophilous and necrophagous insects in order to find their brood substrate. Although volatile organic compounds (VOCs) that are released by carcasses have been identified, little is known about the specific compounds that are used by these insects while searching for a brood substrate. Therefore, we have investigated the chemical ecology involved in the attraction of the necrophagous hide beetle Dermestes maculatus, which feeds as an adult and larva upon decomposing carcasses. Our aims have been to identify the responsible compounds in the odours of the carcass that are important for the attraction of the beetles. Furthermore, we have studied sex- and age-related differences in beetle attraction and tested whether the hide beetle can distinguish between various stages of decomposition by means of the emitted odours. Headspace collection of volatiles released from piglet carcasses (bloated stage, post-bloating stage, advanced decay and dry remains), coupled gas chromatography-mass spectrometry (GC-MS), gas chromatography with electroantennographic detection (GC-EAD) and bioassays were conducted to identify the volatiles responsible for the attraction of the beetles. Freshly emerged male beetles were attracted by the odour of piglets in the post-bloating stage (9 days after death; T(mean) = 27 C) and the EAD-active compound benzyl butyrate. Statistical analysis revealed a higher relative proportion of benzyl butyrate in the odour bouquet of the post-bloating stage in comparison with the other stages. We therefore conclude that this compound plays an important role in the attraction of hide beetles to carcass odour. This underlines the potential use of D. maculatus for the estimation of the post mortem interval. The decomposition stage at which the female beetles are attracted to the odour of a cadaver remains unknown, as does the nature of this attraction. Pheromones (sexual or aggregation pheromones) might play an essential role correlated with their attraction to carrion and consequently with their attraction to the substrate for mating and ovipositioning. PMID:21741784

  6. A cladistic re-analysis of the Gadiformes (Teleostei, Paracanthopterygii) using three-item analysis.

    PubMed

    Grand, Anas; Zarageta Bagils, Rene; Vlez, Lina Mara; Ung, Visotheary

    2014-01-01

    In the present paper, we describe LisBeth, a newly published phylogenetic program. LisBeth implements the cladistic three-item analysis for systematics and biogeography. We show how LisBeth handles character representation, character analysis, exact search functions, reconstruction of the intersection tree and other features, such as retention index, completeness index, character history and link with other programs such as PAUP*, version 4.0b10, TNT and Xper2. Using LisBeth, we reanalyze the phylogeny based on morphological characters of the order Gadiformes (Teleostei, Paracanthopterygii) published by Endo (2002) and compare our results. We also describe the generation of hypotheses of homology following Endo's guidelines versus 3ia representation schemes. We compare the topologies of all results and show the implications of the interpretation of character history. PMID:25544282

  7. Functional incompatibility between the fertilization systems of two allopatric populations of Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Brown, D V; Eady, P E

    2001-11-11

    Recent studies indicate that postcopulatory sexual selection may represent an important component of the speciation process by initiating reproductive isolation via the evolutionary divergence of fertilization systems. Using two geographically isolated populations of the polyandrous beetle Callosobruchus maculatus, we investigated divergence in fertilization systems by determining the extent of postcopulatory functional incompatibility. Through reciprocal, cross-population matings we were able to separately estimate the effects of male and female population origin and their interaction on the extent of last-male sperm precedence, female receptivity to further copulation and female oviposition. Our results indicate partial incompatibility between the fertilization systems of the two populations at all three functional levels. Males derived from the same population as females outcompete rival, allopatric males with respect to sperm preemption, sperm protection, and ability to stimulate female oviposition. This pattern is reciprocated in both populations indicating that postcopulatory, prezygotic events represent important mechanisms by which between-population gene flow is reduced. We suggest the partial gametic isolation observed is a by-product of the coevolution of male and female fertilization systems by a process of cryptic female choice. Our results are consistent with a mechanism akin to conventional mate choice models although they do not allow us to reject antagonistic sexual coevolution as the mechanism of cryptic female choice. PMID:11794785

  8. Use of commercial freezers to control cowpea weevil, Callosobruchus maculatus (Coleoptera: Bruchidae), in organic garbanzo beans.

    PubMed

    Johnson, J A; Valero, K A

    2003-12-01

    One California processor of organic garbanzo beans (Cicer arietinum L.), unable to use chemical fumigants, relies on 30-d storage at -18 degrees C to disinfest product of the cowpea weevil, Callosobruchus maculatus (F). To determine whether the storage period may be shortened, the most cold-tolerant life stage of the cowpea weevil was identified. Laboratory studies showed that the egg stage was most tolerant to -18 degrees C and that adults were most susceptible. To examine the efficacy of cold storage disinfestation, bags of black-eyed peas, Vigna unguiculata (L.) Walp., infested with cowpea weevil eggs were buried within garbanzo bean bins placed in a commercial cold storage facility kept at approximately -18 degrees C and removed after 7, 14, and 21 d. Survival was highest in eggs located at the center of the bins and coincided with the slowest cooling rate. Although temperatures within the bins did not reach -18 degrees C until after 14-19 d, egg mortality was estimated to be >98% after just 7 d of exposure. Complete mortality of eggs occurred after 14 d of cold storage. A 2-wk treatment regimen may be sufficient for control of cowpea weevil in organic legumes. PMID:14977138

  9. Genetic architecture of population differences in oviposition behaviour of the seed beetle Callosobruchus maculatus.

    PubMed

    Fox, C W; Stillwell, R C; Amarillo-S, A R; Czesak, M E; Messina, F J

    2004-09-01

    Few studies have examined the genetic architecture of population differences in behaviour and its implications for population differentiation and adaptation. Even fewer have examined whether differences in genetic architecture depend on the environment in which organisms are reared or tested. We examined the genetic basis of differences in oviposition preference and egg dispersion between Asian (SI) and African (BF) populations of the seed beetle, Callosobruchus maculatus. We reared and tested females on each of two host legumes (cowpea and mung bean). The two populations differed in mean oviposition preference (BF females preferred cowpea seeds more strongly than did SI females) and egg dispersion (SI females distributed eggs more uniformly among seeds than did BF females). Observations of hybrid and backcross individuals indicated that only the population difference in oviposition preference could be explained by complete additivity, whereas substantial dominance and epistasis contributed to the differences in egg dispersion. Both rearing host and test host affected the relative magnitude of population differences in egg dispersion and the composite genetic effects. Our results thus demonstrate that the relative influence of epistasis and dominance on the behaviour of hybrids depends on the behaviour measured and that different aspects of insect oviposition are under different genetic control. In addition, the observed effect of rearing host and oviposition host on the relative importance of dominance and epistasis indicates that the genetic basis of population differences depends on the environment in which genes are expressed. PMID:15312086

  10. Can Preference for Oviposition Sites Initiate Reproductive Isolation in Callosobruchus maculatus?

    PubMed Central

    Rova, Emma; Björklund, Mats

    2011-01-01

    Theory has identified a variety of evolutionary processes that may lead to speciation. Our study includes selection experiments using different host plants and test key predictions concerning models of speciation based on host plant choice, such as the evolution of host use (preference and performance) and assortative mating. This study shows that after only ten generations of selection on different resources/hosts in allopatry, strains of the seed beetle Callosobruchus maculatus develop new resource preferences and show resource-dependent assortative mating when given the possibility to choose mates and resources during secondary contact. The resulting reduced gene flow between the different strains remained for two generations after contact before being overrun by disassortative mating. We show that reduced gene flow can evolve in a population due to a link between host preference and assortative mating, although this result was not found in all lines. However, consistent with models of speciation, assortative mating alone is not sufficient to maintain reproductive isolation when individuals disperse freely between hosts. We conclude that the evolution of reproductive isolation in this system cannot proceed without selection against hybrids. Other possible factors facilitating the evolution of isolation would be longer periods of allopatry, the build up of local adaptation or reduced migration upon secondary contact. PMID:21297947

  11. Lipid Status of the Two High Latitude Fish Species, Leptoclinus maculatus and Lumpenus fabricii

    PubMed Central

    Murzina, Svetlana A.; Nefedova, Zinaida A.; Falk-Petersen, Stig; Ripatti, Pauli O.; Ruokolainen, Tatiana R.; Pekkoeva, Svetlana N.; Nemova, Nina N.

    2013-01-01

    A comparative study of the lipid status (i.e., the total lipid and phospholipid concentrations and the percentage of fatty acids of the total lipids) of adult specimens of daubed shanny (Leptoclinus maculatus) from Svalbard waters (Isfjord) and slender eel blenny (Lumpenus fabricii) from the White Sea (Onega Bay and Tersky shore) was performed to study the metabolism and functions of lipids of these fishes in ontogeny and under various ecological conditions. Slender eel blenny from both areas of the White Sea were distinguished by a high level of sphingomyelin compared with the daubed shanny from Svalbard, and the amount of total phospholipids was higher in slender eel blenny from Onega Bay than in slender eel blenny from the Tersky shore. The extent of saturation and the signature of polyenic fatty acids varied according to the specific species of the Stichaeidae family under study. These results demonstrate the differences in the trophoecological and hydrobiological conditions of habitations of these species and highlighted the importance of considering certain trends in the lipid profiles of these fishes as specific features of the organization of the ecological and biochemical mechanisms of adaptation. PMID:23535338

  12. Molecular genetic response to varied wavelengths of light in Xiphophorus maculatus skin.

    PubMed

    Chang, Jordan; Lu, Yuan; Boswell, William T; Boswell, Mikki; Caballero, Kaela L; Walter, Ronald B

    2015-12-01

    Xiphophorus fishes represent a model often utilized to study UVB induced tumorigenesis. Recently, varied genetic responses to UVB exposure have been documented in the skin of female and male Xiphophorus, as have differences in UVB response in the skin of different parental species and for interspecies hybrids produced from crossing them. Additionally, it has been shown that exposure to "cool white" fluorescent light induces a shift in the genetic profiles of Xiphophorus skin that is nearly as robust as the UVB response, but involves a fundamentally different set of genes. Given these results and the use of Xiphophorus interspecies hybrids as an experimental model for UVB inducible melanoma, it is of interest to characterize genes that may be transcriptionally modulated in a wavelength specific manner. The global molecular genetic response of skin upon exposure of the intact animal to specific wavelengths of light has not been investigated. Herein, we report results of RNA-Seq experiments from the skin of male Xiphophorus maculatus Jp 163 B following exposure to varied 50nm wavelengths of light ranging from 300-600nm. We identify two specific wavelength regions, 350-400nm (88 genes) and 500-550nm (276 genes), that exhibit transcriptional modulation of a significantly greater number of transcripts than any of the other 50nm regions in the 300-600nm range. Observed functional sets of genes modulated within these two transcriptionally active light regions suggest different mechanisms of gene modulation. PMID:26460196

  13. Neotropical monogenoidea. 55. Dactylogyrids parasitising the pintado-amarelo Pimelodus maculatus Lacpde (Actinopterygii: Pimelodidae) from the Rio So Francisco, Brazil.

    PubMed

    Monteiro, Cassandra M; Kritsky, Delane C; Brasil-Sato, Marilia C

    2010-07-01

    Eight species of Dactylogyridae were collected from the gills of the pintado-amarelo Pimelodus maculatus Lacpde in the Rio So Francisco in Brazil: Ameloblastella paranaensis (Frana, Isaac, Pavanelli & Takemoto, 2003) Mendoza-Franco & Scholz, 2009, A. satoi n. sp., Ameloblastella sp., Demidospermus armostus Kritsky & Gutirrez, 1998, D. cf. bidiverticulatum (Suriano & Incorvaia, 1995) Kritsky & Gutirrez, 1998, D. ichthyocercus n. sp., D. paravalenciennesi Gutirrez & Suriano, 1992 and D. uncusvalidus Gutirrez & Suriano, 1992. Two new species, A. satoi n. sp. and D. ichthyocercus n. sp., are described, and A. paranaensis is redescribed. The Rio So Francisco represents new geographical records for the five previously described dactylogyrid species. PMID:20532849

  14. Effects of a chitin binding vicilin from Erythrina velutina seeds on bean bruchid pests (Callosobruchus maculatus and Zabrotes subfasciatus).

    PubMed

    Teixeira, Fabiano M; Oliveira, Adeliana S; Macedo, Leonardo L P; Santos, Elizeu A; de Sales, Mauricio P

    2008-01-01

    Erythrina velutina vicilin, EvV, is a dimeric glycoprotein with Mr of 124.6 kDa. EvV was tested for anti-insect activity against bean bruchid larvae. EvV had LD(50) of 0.10% and ED(50) of 0.14% for Z. subfasciatus and LD(50) of 0.26% and ED(50) of 0.19% for C. maculatus. EvV was not digested by bean larvae enzymes until 12 h of incubation, and at 24 h EvV was more resistant to Z. subfasciatus enzymes. PMID:18336356

  15. Estudio de la formación de galaxias espirales en un modelo de agregación jerárquica

    NASA Astrophysics Data System (ADS)

    Tissera, P.; Saiz, A.; Dominguez-Tenreiro, R.

    El estudio de formación de galaxias espirales ha llevado al desarrollo de numerosos modelos teóricos (e.g. White & Rees 1978). En la actualidad, el modelo más aceptado predice la formación de una galaxia espiral a partir del colapso disipativo del gas en el pozo de potencial de un halo oscuro, conservando su momento angular específco (Fall & Efstathiou 1980). En los últimos años, ha sido posible realizar simulaciones numéricas hidrodinámicas, las cuales describen la evolución conjunta de la materia oscura y los bariones. Estos experimentos han señalado la dificultad de formar estructuras discoidales con propiedades consistentes con las observaciones, en modelos de agregación jerárquica. El problema principal se origina en la pérdida catastrófica de momento angular de la componente disipativa, durante el proceso de ensamblaje de los objetos, a través de la fusión de subestructura (Navarro & Steinmetz 1997). Estos experimentos no incluían procesos de formación estelar. En este trabajo, se expondrán resultados de simulaciones hidrodinámicas cosmológicas, incluyendo formación estelar (Tissera et al 1997), donde ha sido posible reproducir objetos discoidales con contrapartida observacional. El elemento fundamental ha sido la formación de bulbos estelares, los cuales han evitado la pérdida catastrófica de momento angular de los bariones. Se encontró que los discos exponenciales puramente gaseosos son altamente inestables y suceptibles de generar barras, responsables de la pérdida de momento angular y la caída violenta del gas hacia la región central. Estas inestabilidades son fácilmente inducidas durante interacciones y fusiones con objetos vecinos (Barnes & Hernquist 1996). Un bulbo estelar (o un objeto masivo y compacto) estabiliza el disco ante perturbaciones externas, asegurándole un potencial simétrico (Sellwood & Moore 1998, Van der Bosch 1998). En este caso, el gas en el disco no pierde completamente su momento angular intrínseco durante las fusiones, sino que, las sobrevive aportando una contribución distinta de cero, a partir de la cual el disco se regenera acretando en una segunda etapa, gas del halo de acuerdo al modelo tradicional de Fall & Efstathiou.

  16. COWPEA WEEVIL (CALLOSOBRUCHUS MACULATUS) FLIGHTS TO A POINT SOURCE OF FEMALE SEX PHEROMONE: ANALYSES OF FLIGHT TRACKS AT THREE WIND SPEEDS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two-day-old male cowpea weevils, Callosobruchus maculatus, were released individually and flew upwind to a point source of female sex pheromone at three wind speeds. All beetles initiating flight along the pheromone plumes made contact with the pheromone source. Analysis of digitized flight tracks i...

  17. Insecticidal activity of the aqueous extracts of four under-utilized tropical plants as protectant of cowpea seeds from Callosobruchus maculatus infestation.

    PubMed

    Obembe, O M; Kayode, J

    2013-02-15

    The test plants species, namely Crotaria retusa, Hyptis suaveolens, Ricinus communis and Tithonia diversifolia were extracted with water. The extracts were evaluated on Callosobruchus maculatus for mortality, oviposition and adult emergence effects. The long-term protectant ability and viability were also investigated. The results showed that the aqueous extracts from T. diversifolia were most effective on C. maculatus, followed by extract from Ricinus communis. The least potent extracts were those extracted from Crotalaria retusa and Hyptis suaveolens. Also, the extracts considerably reduced oviposition by C. maculatus. Extracts from T. diversifolia and R. communis drastically reduced infestation and subsequence damage of the treated cowpea seeds for a period of three months. Most of the treated seeds germinated after 90 days storage period. The results from this study revealed that aqueous extracts from all the four plants species were effective in controlling cowpea bruchid, C. maculatus and could serve as an alternative to synthetic insecticides for protection of stored cowpea seeds against bruchids. PMID:24171265

  18. Metazoan parasites of Mandi-amarelo Pimelodus maculatus and of Jundi Rhamdia quelen (Osteichthyes: Siluriformes) of Paraba do Sul River, Volta Redonda, Rio de Janeiro.

    PubMed

    Venancio, Aline Cristine Pinto; de Aguiar, Gesilene Ribeiro; Lopes, Patrcia da Silva; Alves, Dimitri Ramos

    2010-01-01

    Forty-one specimens of mandi-amarelo Pimelodus maculatus Lacpde, 1803 (Siluriformes: Pimelodidae) and 54 specimens of jundi Rhamdia quelen (Quoy & Gaimard, 1824) (Siluriformes: Heptapteridae) were collected from the Paraba do Sul River, Volta Redonda, State of Rio de Janeiro, Brazil between November 2007 and October 2008. These fish underwent necropsy so their infracommunities of metazoan parasites could be studied. The same three species of parasites were collected in the two fish species studied. These were one monogenean, one nematode, and one hirudinean. Cucullanus pinnai (Travassos, Artiga, and Pereira, 1928) (Nematoda: Cucullanidae) and Aphanoblastella sp. (Monogenea: Dactylogyridae) were the dominant species with the highest prevalence in P. maculatus and R. quelen. The parasite species of P. maculatus and R. quelen showed an atypical over-dispersed pattern of distribution. No parasite species showed significant correlation between the body total length of the siluriform hosts and their prevalence and abundance. The parasite species richness showed a mean value of 0.87 0.67 (0-2) and 0.57 0.56 (0-2) in P. maculatus and R. quelen, respectively, and no correlation with the body total length. PMID:20943019

  19. Efficacy of Plectranthus glandulosus (Lamiaceae) and Callistemon rigidus (Myrtaceae) Leaf Extract Fractions to Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Danga, Simon Pierre Yinyang; Nukenine, Elias Nchiwan; Younoussa, Lame; Adler, Cornel; Esimone, Charles Okechukwu

    2015-01-01

    As part of on-going efforts to use eco-friendly alternatives to chemical pesticides, methanol crude extracts of Plectranthus glandulosus and Callistemon rigidus leaves were sequentially fractionated in hexane, chloroform, ethyl acetate, and methanol to establish the most active fraction(s) against Callosobruchus maculatus in cowpea. Cowpea seeds (25 g) were treated with 0.5, 1, 2, and 4 g/kg of extract to evaluate the contact toxicity and F1 progeny production of the beetles in the laboratory. Mortality was recorded 1, 3, and 7 d postexposure. P. glandulosus hexane fraction was more toxic than the other fractions recording 100% mortality at 4 g/kg, within 7 d with LC50 of 0.39 g/kg. Hexane fraction of C. rigidus showed superior toxicity, causing 100% mortality at 4 g/kg within only 1 d of exposure with LC50 of 1.02 g/kg. All the fractions greatly reduced progeny emergence, with C. rigidus hexane fraction being the best progeny inhibitor. Fractions of P. glandulosus and C. rigidus leaves had sufficient efficacy to be a component of storage pest management package for C. maculatus. PMID:26443776

  20. Effects of insulin and glucagon on plasma glucose levels and glycogen content in organs of the freshwater teleost Pimelodus maculatus.

    PubMed

    Carneiro, N M; Amaral, A D

    1983-01-01

    Mammalian insulin (350 IU/kg) and glucagon (2.5 mg/kg) were injected intraperitoneally into Pimelodus maculatus, a South American teleost. Extent of carbohydrate regulation was estimated through determination of plasma glucose levels, liver-somatic index, and liver and muscle glycogen contents. The effects of insulin administration, examined 6, 12, 24, 48, and 72 hr after injection, were manifested as a depletion of liver glycogen content after 12 hr and severe decrease in plasma glucose content after 24 hr; insulin had no effect on muscle glycogen or liver-somatic index. The effects of glucagon administration, examined 5, 15, 30, 90, and 360 min after injection, were a small increase in liver glycogen content after 15 min, and hyperglycemia, apparent after 30 min. Glucagon did not affect muscle glycogen or liver-somatic index. Control animals were injected intraperitoneally with saline solution. These results suggest that insulin and glucagon regulate the carbohydrate metabolism of P. maculatus by hormonal mechanisms similar to those operating in other teleost species and in mammals. PMID:6337926

  1. Sexual size and shape dimorphism and allometric scaling patterns in head traits in the New Zealand common gecko Woodworthia maculatus.

    PubMed

    Kelly, Clint D

    2015-08-01

    Sexual dimorphism in shape and size is widespread across animal taxa and arises when natural or sexual selection operates differently on the sexes. Male and female common geckos (Woodworthia maculatus; formerly Hoplodactylus maculatus) in New Zealand do not appear to experience different viability selection pressure, nor do males appear to be under intense pre-copulatory sexual selection. It was therefore predicted that this species would be sexually monomorphic with regard to body size and the size and shape of the head. In line with the prediction, there was no sexual difference in head width, depth, or length or in lateral head shape. However, contrary to prediction, males had a larger body and lateral head size than females. This study suggests that males, at least on Maud Island, NZ, might be under stronger pre-copulatory sexual selection than previously recognized and thus have evolved larger heads (i.e. lateral head size) for use in male combat for females. Allometric scaling patterns do not differ between the sexes and suggest that head width and depth are under directional selection whereas lateral head size is under stabilizing selection. Diet ecology - an agent of natural selection common to both sexes - is likely largely responsible for the observed patterns of head size and shape and the lack of sexual dimorphism in them. PMID:25958103

  2. Potential of the Lectin/Inhibitor Isolated from Crataeva tapia Bark (CrataBL) for Controlling Callosobruchus maculatus Larva Development.

    PubMed

    Nunes, Natalia N S; Ferreira, Rodrigo S; Silva-Lucca, Rosemeire A; de S, Leonardo F R; de Oliveira, Antnia Elenir A; Correia, Maria Tereza Dos S; Paiva, Patrcia Maria G; Wlodawer, Alexander; Oliva, Maria Luiza V

    2015-12-01

    Callosobruchus maculatus is an important predator of cowpeas. Due to infestation during storage, this insect affects the quality of seed and crop yield. This study aimed to investigate the effects of CrataBL, a multifunction protein isolated from Crataeva tapia bark, on C. maculatus larva development. The protein, which is stable even in extreme pH conditions, showed toxic activity, reducing the larval mass 45 and 70% at concentrations of 0.25 and 1.0% (w/w), respectively. Acting as an inhibitor, CrataBL decreased by 39% the activity of cysteine proteinases from larval gut. Conversely, the activity of serine proteinases was increased about 8-fold. The toxic properties of CrataBL may also be attributed to its capacity of binding to glycoproteins or glycosaminoglycans. Such binding interferes with larval metabolism, because CrataBL-FITC was found in the fat body, Malpighian tubules, and feces of larvae. These results demonstrate the potential of this protein for controlling larva development. PMID:26568149

  3. Efficacy of Plectranthus glandulosus (Lamiaceae) and Callistemon rigidus (Myrtaceae) Leaf Extract Fractions to Callosobruchus maculatus (Coleoptera: Bruchidae)

    PubMed Central

    Danga, Simon Pierre Yinyang; Nukenine, Elias Nchiwan; Younoussa, Lame; Adler, Cornel; Esimone, Charles Okechukwu

    2015-01-01

    As part of on-going efforts to use eco-friendly alternatives to chemical pesticides, methanol crude extracts of Plectranthus glandulosus and Callistemon rigidus leaves were sequentially fractionated in hexane, chloroform, ethyl acetate, and methanol to establish the most active fraction(s) against Callosobruchus maculatus in cowpea. Cowpea seeds (25 g) were treated with 0.5, 1, 2, and 4 g/kg of extract to evaluate the contact toxicity and F1 progeny production of the beetles in the laboratory. Mortality was recorded 1, 3, and 7 d postexposure. P. glandulosus hexane fraction was more toxic than the other fractions recording 100% mortality at 4 g/kg, within 7 d with LC50 of 0.39 g/kg. Hexane fraction of C. rigidus showed superior toxicity, causing 100% mortality at 4 g/kg within only 1 d of exposure with LC50 of 1.02 g/kg. All the fractions greatly reduced progeny emergence, with C. rigidus hexane fraction being the best progeny inhibitor. Fractions of P. glandulosus and C. rigidus leaves had sufficient efficacy to be a component of storage pest management package for C. maculatus. PMID:26443776

  4. Across the southern Andes on fin: glacial refugia, drainage reversals and a secondary contact zone revealed by the phylogeographical signal of Galaxias platei in Patagonia.

    PubMed

    Zemlak, Tyler S; Habit, Evelyn M; Walde, Sandra J; Battini, Miguel A; Adams, Emily D M; Ruzzante, Daniel E

    2008-12-01

    We employed DNA sequence variation at two mitochondrial (control region, COI) regions from 212 individuals of Galaxias platei (Pisces, Galaxiidae) collected throughout Patagonia (25 lakes/rivers) to examine how Andean orogeny and the climatic cycles throughout the Quaternary affected the genetic diversity and phylogeography of this species. Phylogenetic analyses revealed four deep genealogical lineages which likely represent the initial division of G. platei into eastern and western lineages by Andean uplift, followed by further subdivision of each lineage into separate glacial refugia by repeated Pleistocene glacial cycles. West of the Andes, refugia were likely restricted to the northern region of Patagonia with small relicts in the south, whereas eastern refugia appear to have been much larger and widespread, consisting of separate northern and southern regions that collectively spanned most of Argentinean Patagonia. The retreat of glacial ice following the last glacial maximum allowed re-colonization of central Chile from nonlocal refugia from the north and east, representing a region of secondary contact between all four glacial lineages. Northwestern glacial relicts likely followed pro-glacial lakes into central Chilean Patagonia, whereas catastrophic changes in drainage direction (Atlantic --> Pacific) for several eastern palaeolakes were the likely avenues for invasions from the east. These mechanisms, combined with evidence for recent, rapid and widespread population growth could explain the extensive contemporary distribution of G. platei throughout Patagonia. PMID:19017262

  5. Offspring production with cryopreserved sperm from a live-bearing fish Xiphophorus maculatus and implications for female fecundity✰

    PubMed Central

    Yang, Huiping; Savage, Markita G.; Hazlewood, Leona; Walter, Ronald B.; Tiersch, Terrence R.

    2011-01-01

    Xiphophorus fishes are well-established models for biomedical research of spontaneous or induced tumors, and their use in research dates back to the 1930’s. Currently, 58 well-pedigreed lines exist among 24 Xiphophorus species housed as live animals at the Xiphophorus Genetic Stock Center. The technique of sperm cryopreservation has been applied to preserve these valuable genetic resources, and production of offspring has been reported with cryopreserved sperm in two species (X. helleri and X. couchianus). The goal of this research was to establish protocols for sperm cryopreservation and artificial insemination that yield live young in X. maculatus, a widely used research species. The objectives were to: 1) collect basic biological characteristics of males, and quantify the sperm production yield after crushing of dissected testis; 2) cryopreserve sperm from X. maculatus by adapting as necessary the protocols for sperm cryopreservation of X. helleri and X. couchianus; 3) use cryopreserved sperm to inseminate virgin females of X maculatus and other species (X. helleri and X. couchianus), and 4) compare experimental trials over a 3-year period to identify opportunities for improving female fecundity. In total, 117 males were used in this study with a standard length of 2.5 ± 0.3 cm (mean ± SD), body weight of 0.474 ± 0.149 g, and dissected testis weight of 7.1 ± 3.7 mg. Calculation of sperm availability showed 5.9 ± 2.8 × 106 sperm cells per mg of testis weight. Offspring were produced from cryopreserved sperm. Male-to-male variation (1-70%) was observed in post-thaw motility despite little variation in motility before freezing (60-90%) or genetic variation (~100 generations of sib-mating). Comparisons of biological factors of males did not have significant correlations with the production of live young, and the influence of females on production of young were identified from the comparison of artificial insemination over the 3 yr. Overall, this study describes offspring production from cryopreserved sperm in a third species of Xiphophorus fishes, and identifies the opportunities for improving female fecundity which is essential for establishment of germplasm repositories for Xiphophorus fishes. PMID:21616165

  6. Histological description of tooth formation in adult Eretmodus cf. cyanostictus (Teleostei, Cichlidae).

    PubMed

    Vandervennet, E; Huysseune, A

    2005-07-01

    The Eretmodini, a tribe of closely related cichlids (Teleostei, Cichlidae) originating from Lake Tanganyika, possess oral tooth shapes ranging from conical (in Tanganicodus) over cylindrical (in Spathodus) to spatulate (in Eretmodus). Prior to a study aiming to understand how these distinctly different tooth shapes can be acquired in such closely related taxa, a detailed histological study was required of tooth formation in a representative of the eretmodines. Here, we present a histological description of replacement tooth development in Eretmodus cf. cyanostictus. Using light-microscopic observations on semithin as well as on ground sections, microradiographs and stereo-microscopic observations of both alizarine red S stained and unstained jaws we can conclude that tooth formation in adult E. cf. cyanostictus roughly corresponds with what is known for teleost tooth development in general. Remarkable features include the localization and shape of the epithelial downgrowth, the transient presence of a layer intermediate between inner dental epithelium (IDE) and outer dental epithelium (ODE), the asymmetric shape of the enamel organ, the fact that the pulp cavity recedes in front of the forming enameloid during enameloid formation, and finally, the pattern of matrix mineralisation and maturation, and the presence of pigment in the enameloid. The observation that the enamel organ in adult E. cf. cyanostictus develops asymmetrically is significant for understanding tooth shape variation in the Eretmodini. PMID:15892949

  7. Improved resolution and a novel phylogeny for the Neotropical triplefin blennies (Teleostei: Tripterygiidae).

    PubMed

    Miller, Elizabeth Christina; Lin, Hsiu-Chin; Hastings, Philip A

    2016-03-01

    The triplefin blennies (Teleostei: Tripterygiidae) are a diverse group of small-bodied benthic fishes associated with rocky or coral reefs. The Neotropics contain four genera and 26 species, many of which have only been recently described. A recent molecular phylogeny (Lin and Hastings, 2013) contrasts with previous phylogenies based on morphology in recovering the four Neotropical genera as a single clade with respect to the Indo-Pacific genera; however, relationships within and among genera were poorly resolved. This study reports a novel topology based on an expanded seven-loci molecular dataset. Individual gene trees have poor resolution, but concatenated analyses show strong support for most nodes, likely due to emergent support from concatenation. Consistent with Lin and Hastings (2013), three of the Neotropical genera, Axoclinus, Enneanectes, and Crocodilichthys, form a well-supported clade, but relationships of the fourth (Lepidonectes) are not confidently resolved. The monophyly of Axoclinus is well supported, but Enneanectes is paraphyletic with the inclusion of Axoclinus and Crocodilichthys. Improved resolution allows for reinterpretation of the biogeography of the Neotropical Tripterygiidae. Broader taxon sampling is still necessary for resolving the relationships within Tripterygiidae globally. PMID:26718057

  8. Molecular systematics of the enigmatic Middle American genus Vieja (Teleostei: Cichlidae).

    PubMed

    McMahan, Caleb D; Geheber, Aaron D; Piller, Kyle R

    2010-12-01

    The genus Vieja represents a group of heroine cichlids (Teleostei: Cichlidae) distributed on the Atlantic and Pacific slopes of North and Central America from southern Mexico to Panama. Sixteen species of Vieja are presently recognized; however, based on long-standing taxonomic problems, the genus itself appears to be weakly defined. A number of different generic designations have been proposed for members of Vieja, and recent systematic studies of heroine cichlids have not specifically addressed the validity of the grouping and have not included all species in the genus. Therefore, the purpose of this study was to assess the monophyly of the genus Vieja by including all nominal species in the genus using the mitochondrial encoded cytochrome b gene and nuclear S7-1 intron. Results of Maximum Parsimony, Bayesian inference, and topology tests (constraint tree searches and post-burn-in Bayesian filtering) indicate that the genus is not monophyletic as it is currently recognized. The genus Herichthys was recovered as sister to a clade consisting of a number of Vieja species (V. fenestrata, V. guttulata, V. zonata, V. hartwegi, V. bifasciata, V. breidohri, V. argentea, V. regani, V. melanura, V. synspila, and V. maculicauda, as well as Paraneetroplusbulleri). A clade consisting of V. intermedia, V. godmanni, and V. microphthalma was recovered sister to Theraps. Additionally, V. heterospila and V. tuyrensis were recovered outside of Vieja and Herichthys clades. Based on the results of this comprehensive study, we suggest a revised classification of Vieja species. PMID:20849962

  9. Structural chromosome polymorphism in a Pimelodus maculatus La Cepde, 1803 population (Siluriformes, Pimelodidae) from the Paranapanema River basin, PR, Brazil.

    PubMed

    Mazzuchelli, J; Swara, A C; Dias, A L

    2007-12-01

    In the present cytogenetic study of Pimelodus maculatus, 13 specimens (8 males and 5 females) from the Congonhas Stream in Paran State, Brazil, were examined using conventional staining. All of them showed a karyotype of 2n=56, with a chromosome distribution of 20m + 20sm + 10st + 6a. However, four individuals (2 males and 2 females) were found to have a variant karyotype (cytotype) with two heteromorphic chromosomes in the group of submetacentric chromosomes--one of them corresponds to the second largest chromosome of this group and the other is a chromosome of small size. This variation suggests the existence of a structural polymorphism in the studied population. PMID:18278362

  10. Effect of some metal ions on blood and liver delta-aminolevulinate dehydratase of Pimelodus maculatus (Pisces, Pimelodidae).

    PubMed

    Rodrigues, A L; Bellinaso, M L; Dick, T

    1989-01-01

    1. delta-ALA-D from Pimelodus maculatus was inhibited in vitro by Cd2+ greater than Pb2+ greater than Hg2+ greater than Cu2+ greater than Zn2+ in blood and by Pb2+ greater than Cd2+ greater than Hg2+ greater than Cu2+ = Zn2+ in the liver. 2. Kinetic analysis of the inhibition by the metal ions showed that Cd2+ and Hg2+ act as non-competitive inhibitors on both sources. 3. Pb2+ showed a mixed type of inhibition in blood and a non-competitive type in the liver. 4. Zn2+ acted as a competitive or mixed inhibitor, on both sources, depending on concentration. PMID:2598636

  11. New species of Cerambycinae from the Neotropical Region, and nomen novum for Anelaphus maculatus Galileo, Martins, and Santos-Silva, 2014 (Elaphidiini).

    PubMed

    Galileo, Maria Helena M; Martins, Ubirajara R; Santos-Silva, Antonio

    2015-01-01

    Six new species and one new genus are described: Criodion spinosum sp. nov. (Cerambycini), from Bolivia; Eburodacrys wappesi sp. nov. and Eburodacrys skillmani sp. nov. (Eburiini), from Bolivia; Eupempelus rileyorum sp. nov. (Heteropsini) from Panama; Sphalloeme mexicana sp. nov. (Oemini), from Mexico; Wappesoeme camiri sp. nov., new genus (Oemini), from Bolivia. Wappesoeme, Eburodacrys wappesi, E. skillmani, Eupempelus rileyorum, and Criodion spinosum are included in previously published keys. Anelaphus erakyra nomen novum for A. maculatus Galileo et al., 2014 is established. PMID:26250192

  12. Phylogenetic relationships of bitterling fishes (Teleostei: Cypriniformes: Acheilognathinae), inferred from mitochondrial cytochrome B sequences.

    PubMed

    Kawamura, Kouichi; Ueda, Takayoshi; Arai, Ryoichi; Smith, Carl

    2014-05-01

    Bitterling (Teleostei: Acheilognathinae) are small cyprinid fishes with a discrete distribution in East Asia and Europe. We used a complete mitochondrial cytochrome b sequence (1141 bp) from 49 species or subspecies in three genera (Tanakia, Rhodeus, and Acheilognathus), sampled across the major part of their distribution, to elucidate their phylogeny and biogeography, focusing particularly on their origin and dispersal. Based on high support value, the monophyletic Acheilognathinae separated into two major clades, Acheilognathus and Tanakia-Rhodeus. In the latter clade, the monophyly of Rhodeus was poorly supported, though it was topologically nested in Tanakia. On the basis of molecular-clock calibration, both clades diverged in the middle Miocene, with Tanakia-Rhodeus diverging slightly earlier than Acheilognathus. The Tanakia-Rhodeus clade expanded its distribution westward from the Far East, eventually reaching Europe, while Acheilognathus dispersed in the temperate regions of East Asia. A feature common to both clades is that most extant species, including Japanese endemics, appeared by the end of the Pliocene, corresponding with the present delineation of the Japanese archipelago. Autumn-spawning species with an embryonic diapause, unique to bitterling among cyprinid fishes, formed two distinct lineages (barbatulusrhombeus and longipinnis-typus) within Acheilognathus. The estimated time of divergence of the two lineages was approximately from the late Pliocene, a period characterized by glaciations. The timing of divergence suggests that the shift of spawning from spring to autumn, coupled with embryonic diapause, convergently emerged twice in the evolution of bitterling, possibly as an adaptation to the climate of the late Pliocene. PMID:24832905

  13. An Anomalous Hatchery-Reared Biwa Rock Catfish, Silurus lithophilus (Teleostei: Siluridae),with an Adipose Fin-Like Projection.

    PubMed

    Kitagawa, Tetsuro; Hosoya, Kazumi

    2015-10-01

    An anomalous individual with an adipose fin-like projection was discovered during seedling production of Biwa rock catfish, Silurus lithophilus (Teleostei: Siluridae). The external shape of the projection resembled an adipose fin, but soft rays were clearly observed within it. The projection was proximally supported by a series of pterygiophores and by 14 soft rays. The projection can be explained as: I, homologous with a primitive adipose fin, which occurred as a result of localized ontogenetic reversion; II, an extra fin that occurred as a result of abnormal expression of a regeneration mechanism; III, a remnant of a dorsal fin and/or a second dorsal fin; and IV, an inversion phenomenon of the polarity in the formation process of the anal fin. PMID:26428720

  14. A screen for bacterial endosymbionts in the model organisms Tribolium castaneum, T. confusum, Callosobruchus maculatus, and related species.

    PubMed

    Goodacre, Sara L; Fricke, Claudia; Martin, Oliver Y

    2015-04-01

    Reproductive parasites such as Wolbachia are extremely widespread amongst the arthropods and can have a large influence over the reproduction and fitness of their hosts. Undetected infections could thus confound the results of a wide range of studies that focus on aspects of host behavior, reproduction, fitness, and degrees of reproductive isolation. This potential problem has already been underlined by work investigating the incidence of Wolbachia infections in stocks of the model system Drosophila melanogaster. Here we survey a range of lab stocks of further commonly used model arthropods, focusing especially on the flour beetles Tribolium castaneum and Tribolium confusum, the cowpea weevil Callosobruchus maculatus and related species (Coleoptera: Tenebrionidae and Bruchidae). These species are widespread stored product pests so knowledge of infections with symbionts further has potential use in informing biocontrol measures. Beetles were assessed for infection with 3 known microbial reproductive parasites: Wolbachia, Rickettsia, Spiroplasma. Infections with some of these microbes were found in some of the lab stocks studied, although overall infections were relatively rare. The consequences of finding infections in these or other species and the type of previous studies likely to be affected most are discussed. PMID:24347564

  15. Influence of environmental temperature on the fatty acid desaturation and elongation activity of fish (Pimelodus maculatus) liver microsomes.

    PubMed

    de Torrengo, M; Brenner, R R

    1976-01-22

    The effect of environmental temperature on the activity of liver microsomes of fish (Pimelodus maculatus) to desaturate and elongate oleic, linoleic and alpha-linolenic acids was studied. It was found that: 1. Fish kept at 14-15 degrees C had higher desaturation and elongation activity than animals kept at 29-30 degrees C. The ratio of activity was the same for the three fatty acids. 2. A decrease of the environmental temperature increased the V of linoleic acid desaturation to gamma-linolenic acid, but did not modify the approximate Km of the reaction. 3. The inactivation of the delta6-desaturase of microsomes separated from fish kept at 29-30 degrees C and 14-15 degrees C was the same when heated at 40 degrees C. However, the enzyme was deactivated faster when heated at 29-30 degrees C than at 14-15 degrees C. 4. The increase of the delta6-desaturation activity of the microsomes evoked by the decrease of the temperature of the aquarium was mostly compensated for by the correlative decrease of the specific reaction rate of the reaction. For this reason it is assumed that the adaptive change of the desaturation activity of the microsomes with the environmental temperature does not greatly modify the fatty acid composition of the fish. PMID:1252479

  16. A RAD-Tag Genetic Map for the Platyfish (Xiphophorus maculatus) Reveals Mechanisms of Karyotype Evolution Among Teleost Fish

    PubMed Central

    Amores, Angel; Catchen, Julian; Nanda, Indrajit; Warren, Wesley; Walter, Ron; Schartl, Manfred; Postlethwait, John H.

    2014-01-01

    Mammalian genomes can vary substantially in haploid chromosome number even within a small taxon (e.g., 340 among deer alone); in contrast, teleost fish genomes are stable (2425 in 58% of teleosts), but we do not yet understand the mechanisms that account for differences in karyotype stability. Among perciform teleosts, platyfish (Xiphophorus maculatus) and medaka (Oryzias latipes) both have 24 chromosome pairs, but threespine stickleback (Gasterosteus aculeatus) and green pufferfish (Tetraodon nigroviridis) have just 21 pairs. To understand the evolution of teleost genomes, we made a platyfish meiotic map containing 16,114 mapped markers scored on 267 backcross fish. We tiled genomic contigs along the map to create chromosome-length genome assemblies. Genome-wide comparisons of conserved synteny showed that platyfish and medaka karyotypes remained remarkably similar with few interchromosomal translocations but with numerous intrachromosomal rearrangements (transpositions and inversions) since their lineages diverged ?120 million years ago. Comparative genomics with platyfish shows how reduced chromosome numbers in stickleback and green pufferfish arose by fusion of pairs of ancestral chromosomes after their lineages diverged from platyfish ?195 million years ago. Zebrafish and human genomes provide outgroups to root observed changes. These studies identify likely genome assembly errors, characterize chromosome fusion events, distinguish lineage-independent chromosome fusions, show that the teleost genome duplication does not appear to have accelerated the rate of translocations, and reveal the stability of syntenies and gene orders in teleost chromosomes over hundreds of millions of years. PMID:24700104

  17. Sex-specific genetic variances in life-history and morphological traits of the seed beetle Callosobruchus maculatus

    PubMed Central

    Hallsson, Lára R; Björklund, Mats

    2012-01-01

    Knowledge of heritability and genetic correlations are of central importance in the study of adaptive trait evolution and genetic constraints. We use a paternal half-sib-full-sib breeding design to investigate the genetic architecture of three life-history and morphological traits in the seed beetle, Callosobruchus maculatus. Heritability was significant for all traits under observation and genetic correlations between traits (rA) were low. Interestingly, we found substantial sex-specific genetic effects and low genetic correlations between sexes (rMF) in traits that are only moderately (weight at emergence) to slightly (longevity) sexually dimorphic. Furthermore, we found an increased sire () compared to dam () variance component within trait and sex. Our results highlight that the genetic architecture even of the same trait should not be assumed to be the same for males and females. Furthermore, it raises the issue of the presence of unnoticed environmental effects that may inflate estimates of heritability. Overall, our study stresses the fact that estimates of quantitative genetic parameters are not only population, time, environment, but also sex specific. Thus, extrapolation between sexes and studies should be treated with caution. PMID:22408731

  18. Genetic variability and resistance of cultivars of cowpea [Vigna unguiculata (L.) Walp] to cowpea weevil (Callosobruchus maculatus Fabr.).

    PubMed

    Vila Nova, M X; Leite, N G A; Houllou, L M; Medeiros, L V; Lira Neto, A C; Hsie, B S; Borges-Paluch, L R; Santos, B S; Araujo, C S F; Rocha, A A; Costa, A F

    2014-01-01

    The cowpea weevil (Callosobruchus maculatus Fabr.) is the most destructive pest of the cowpea bean; it reduces seed quality. To control this pest, resistance testing combined with genetic analysis using molecular markers has been widely applied in research. Among the markers that show reliable results, the inter-simple sequence repeats (ISSRs) (microsatellites) are noteworthy. This study was performed to evaluate the resistance of 27 cultivars of cowpea bean to cowpea weevil. We tested the resistance related to the genetic variability of these cultivars using ISSR markers. To analyze the resistance of cultivars to weevil, a completely randomized test design with 4 replicates and 27 treatments was adopted. Five pairs of the insect were placed in 30 grains per replicate. Analysis of variance showed that the number of eggs and emerged insects were significantly different in the treatments, and the means were compared by statistical tests. The analysis of the large genetic variability in all cultivars resulted in the formation of different groups. The test of resistance showed that the cultivar Inhuma was the most sensitive to both number of eggs and number of emerged adults, while the TE96-290-12-G and MNC99-537-F4 (BRS Tumucumaque) cultivars were the least sensitive to the number of eggs and the number of emerged insects, respectively. PMID:24737480

  19. Anlisis estadstico bivariante de galaxias

    NASA Astrophysics Data System (ADS)

    Martn, M. C.

    We present a comprehensive multi-frequency statistical analysis of spiral and irregular galaxies using data available in the literature. Global far UV, far IR, neutral hydrogen, radio continuum at 1.4 GHz and optical global parameters for large samples, are analyzed by different statistical methods. The aim of this paper has been to review the integral properties of galaxies. For this proposal, the work is based on more complete multi-wavelength samples and the use of simple but consistent statistical tools. As we also identified in the samples those galaxies which are in rich clusters, we could check their properties with respect to isolated galaxies.

  20. Galaxias con ncleo doble. III

    NASA Astrophysics Data System (ADS)

    Gimeno, G.; Daz, R. J.; Carranza, G.

    We performed new spectroscopic and photometric observations of late type galaxies with double nuclei and without previous studies. The subsample, constituted by double nuclei galaxies without tidal tails, was selected from the Double Nuclei Galaxies Preliminary Catalog (Gimeno, Daz & Carranza 1999) and the observations were performed at Bosque Alegre Astrophysical Station. We report and discuss specially the results for ESO 416-G06, ESO 381-IG23 and Fairal 58. In all cases the secondary nucleus presents bluer color indexes than the main nucleus and also larger H? equivalent widths. These objects follow the trend of smaller radial velocity differences when smaller are the separations between both nuclei; this correlation was observed in previous works (e.g. Gimeno, Daz & Carranza 1998). The general picture is consistent with the scenario of star formation enhanced by the capture of a minor or satellite galaxy.

  1. The importance of gobies (Gobiidae, Teleostei) as hosts and transmitters of parasites in the SW Baltic

    NASA Astrophysics Data System (ADS)

    Zander, C. D.; Strohbach, U.; Groenewold, S.

    1993-02-01

    The parasite fauna of five goby species (Gobiidae, Teleostei) was investigated in the Baltic Sea during the period 1987 to 1990. 13 parasite species were found in samples from the Lübeck Bight: Bothriocephalus scorpii, Schistocephalus sp. (Cestoda); Cryptocotyle concavum, Cryptocotyle lingua, Podocotyle atomon, Derogenes varicus (Digenea); Hysterothylacium sp. (cf. auctum), Contracaecum sp., Anisakis simplex (Nematoda); Corynosoma sp., Echinorhynchus gadi, Neoechinorhynchus rutili, Pomphorhynchus laevis (Acanthocephala). The number of parasite species were: 10 in the sand goby Pomatoschistus minutus, 8 in the black goby Gobius niger, 7 in the two-spotted goby Gobiusculus flavescens, 6 in the common goby Pomatoschistus microps, and 5 in the painted goby Pomatoschistus pictus. Neoechinorhynchus rutili occurred only in P. minutus, and Corynosoma sp. only in G. niger. The extent to which the gobies were parasitized clearly depended on the respective ways of life and, moreover, on the kind of prey ingested by the hosts. Additionally, the age of the hosts might be important. The highest rate of parasitism, more than 60%, was reached by Hysterothylacium sp. in G. niger and by Cryptocotyle concavum in P. microps. Infestation incidence lay mostly below 40% which means a satellite species status (Holmes, 1991). The number of parasite species was highest in summer; the highest intensities of single parasites occurred in spring ( Podocotyle atomon) or autumn ( Crytocotyle concavum). Bothriocephalus scorpii, Hysterothylacium sp. and Podocotyle infested their juvenile hosts very early, but only Hysterothylacium was accumulated by G. niger during its whole life span, whereas Bothriocephalus persisted also in older gobies in low intensities. The cercariae of Cryptocotyle spp. penetrate actively into their hosts; all the other parasites named were transmitted in larval form by prey organisms which consisted mainly of planktonic and benthic crustaceans. The gobies were final hosts for only 5 parasites; but two species may be transmitted to larger fish, and 6 species to sea birds or mammals. The parasite community of the five gobies may possibly be taken to characterize the ecological quality of the environment of the Lübeck Bight.

  2. Growth and reproduction aspects of Pimelodus maculatus Lacpde, 1803 (Siluriformes, Pimelodidae) of the Cachoeira Dourada reservoir, state of Gois and Minas Gerais, Brazil.

    PubMed

    Sabinson, L M; Rodrigues Filho, J L; Peret, A C; Verani, J R

    2014-05-01

    Growth and reproduction parameters of the yellow-mandi, Pimelodus maculatus Lacpde, 1803 (Siluriformes, Pimelodidae), were determined for the Cachoeira Dourada reservoir (GO/MG). The field work occurred throughout February 2007 to January 2008 (with the exception of December 2007). Gill nets with mesh sizes from 1.5 to 10 centimeters were placed in three different areas in the reservoir and were collected 24 hours later. A total of 538 specimens were captured, amongst which 242 were females, 219 were males and 77 could not have their sex determined. Sex ratio differed from 1:1 only during July 2007 and January 2008, with males and females predominating in each of those months. Males occupied the medium length classes (18.9 to 24.3 cm) while females were most abundant in the superior classes (from 27 to 37.8 cm).The growth constant K was statistically equal for males (K=0.1851) and females (K=0.1708), however, females P. maculatus may have a greater investment in reproductive tissue, a fact indicated by the elevated values of Kn and GSI during the summer. Bearing in mind that P. maculatus reproduces in the rainy season, a greater gain in weight is expected during the months before the reproduction season, and that after it occurs the fish loses fat and weight as a consequence of metabolic effort. Still, the absence of juveniles may be an indication that the species did not find in the reservoir the proper conditions for reproduction and growth of its fry. PMID:25166330

  3. Effects of a chitin-binding vicilin from Enterolobium contortisiliquum seeds on bean bruchid pests (Callosobruchus maculatus and Zabrotes subfasciatus) and phytopathogenic fungi (Fusarium solani and Colletrichum lindemuntianum).

    PubMed

    Moura, Fabiano T; Oliveira, Adeliana S; Macedo, Leonardo L P; Vianna, André L B R; Andrade, Lucia B S; Martins-Miranda, A S; Oliveira, Jose T A; Santos, Elizeu A; de Sales, Mauricio P

    2007-01-24

    Chitin-binding vicilin from Enterolobium contortisiliquum seeds was purified by ammonium sulfate followed by gel filtration on Sephacryl 300-SH and on Sephacryl 200-SH. The vicilin, called EcV, is a dimeric glycoprotein composed of 1.03% carbohydrates and a Mr of 151 kDa, consisting of two subunits of Mr of 66.2 and 63.8 kDa. The EcV homogeneity was confirmed in a PAGE where it was observed to be a unique acid protein band with slow mobility in this native gel. E. contortisiliquum vicilin (EcV) was tested for anti-insect activity against C. maculatus and Zabrotes subfasciatus larvae and for phytopathogenic fungi, F. solani and C. lindemuntianum. EcV was very effective against both bruchids, producing 50% mortality for Z. subfasciatus at an LD50 of 0.43% and affected 50% of the larvae mass with an ED50 of 0.65%. In artificial diets given to C. maculatus, 50% of the larvae mass was affected with an ED50 of 1.03%, and larva mortality was 50% at LD50 of 1.11%. EcV was not digested by midgut homogenates of C. maculatus and Z. Subfasciatus until 12 h of incubation, and at 24 h EcV was more resistant to Z. subfasciatus larval proteases. The binding to chitin present in larvae gut associated to low EcV digestibility could explain its lethal effects. EcV also exerted an inhibitory effect on the germination of F. solani at concentrations of 10 and 20 microg mL-1. The effect of EcV on fungi is possibly due to binding to chitin-containing structures of the fungal cell wall. PMID:17227051

  4. Effect of diatomaceous earths Fossil Shield and Silico-Sec on the egg laying behaviour of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae).

    PubMed

    Prasantha, B D Rohitha; Reichmuth, Ch; Büttner, C

    2002-01-01

    The pulse beetle, Callosobruchus maculatus (F.) is a destructive pest of pulses in both storage and field. It is well known that diatomaceous earth (DE) kill the insects by locally absorbing the epicuticular lipid layers leading to high rate of water loss through the cuticle. However, the effectiveness of DE depends on its ability to kill the adults before copulation and egg-laying. Newly emerged virgin males and females of Callosobruchus maculatus (F.) were exposed to the DEs, Fossil-Shield and Silico-Sec on 30 treated mungbeans (Vigna radita (L)). Fecundity, number of beans used for egg-laying and beans without eggs were evaluated after four days; the number of unhatched eggs was evaluated after ten days. It was determined, that the fecundity of female insects decreased sigmoidely with increasing rate of DE content. Percentages of unhatched eggs and seeds without eggs increased with increasing DE dosages. However, the maximum egg densities (eggs per used secd) occurred at 1200 mg DE/kg for Fossil-Shield and Silico-Sec. The reason for such DE-stimulated behaviour of egg laying expressed as a number of seeds with eggs of C. maculatus is not known, but it may be related to the stress caused by the inert dusts or to the reduction of both chemical and physical (tactile) stimuli. Treatment with DEs altered the surface texture of the beans and caused less cohesion between eggs and the seed surface. Only few larvae managed to penetrate into the grains, possibly due to increased grain roughness and repellent effect of DE. A relatively high number of eggs were laid on the surface of those beans where the amount of dust had been locally reduced by adults' movement and their pick up of DE. Therefore, several larvae tried to penetrate into these treated beans, causing a high larval density per partially cleaned bean. All these reasons lead to a progeny decline. PMID:12703482

  5. The distribution of neuropeptide Y and dynorphin immunoreactivity in the brain and pituitary gland of the platyfish, Xiphophorus maculatus, from birth to sexual maturity

    NASA Technical Reports Server (NTRS)

    Cepriano, L. M.; Schreibman, M. P.

    1993-01-01

    Immunoreactive neuropeptide Y and dynorphin have been localized in the brain and pituitary gland of the platyfish, Xiphophorus maculatus, at different ages and stages of development from birth to sexual maturity. Immunoreactive neuropeptide Y was found in perikarya and tracts of the nucleus olfactoretinalis, telencephalon, ventral tegmentum and in the neurohypophysis and in the three regions of the adenohypophysis. Immunoreactive dynorphin was found in nerve tracts in the olfactory bulb and in cells of the pars intermedia and the rostral pars distalis of the pituitary gland.

  6. Isolation and purification of a papain inhibitor from Egyptian genotypes of barley seeds and its in vitro and in vivo effects on the cowpea bruchid, Callosobruchus maculatus (F.).

    PubMed

    Abd El-Latif, Ashraf Oukasha

    2015-02-01

    The cysteine inhibitors that are known as cystatin have been identified and characterized from several plant species. In the current study, 44 barley (Hordeum vulgare) genotypes including 3 varieties and 41 promising lines were screened for their potential as protease inhibitors. The barley genotypes showed low inhibitory activity against trypsin and chymotrypsin enzymes with a mean of 4.15 TIU/mg protein and 4.40 CIU/mg protein. The barley variety, Giza 123, showed strong papain inhibitory activity of 97.09 PIU/mg proteins and was subjected for further purification studies using ammonium sulfate fractionation and DEAE-Sephadex A-25 column. Barley purified proteins showed two bands on SDS-PAGE corresponding to a molecular mass of 12.4-54.8 kDa. The purified barley PI was found to be stable at a temperature below 80 °C and at a wide range of pH from 2 to 12. Barley PI was found to have higher potential inhibitory activity against papain enzyme compared to the standard papain inhibitor, E-64 with an IC50 value of 21.04 µg/ml and 25.62 µg/ml for barley PI and E-64, respectively. The kinetic analysis revealed a non-competitive type of inhibition with a Ki value of 1.95 × 10(-3 )µM. The antimetabolic effect of barley PI was evaluated against C. maculatus by incorporating the F30-60 protein of the purified inhibitor into the artificial diet using artificial seeds. Barley PI significantly prolonged the development of C. maculatus in proportion to PI concentration. Barley PI significantly increased the mortality of C. maculatus and caused a significant reduction in its fecundity. On the other hand, barley PI seemed to have non-significant effects on the adult longevity and the adult dry weight. The in vitro and in vivo results proved the efficiency of the papain inhibitory protein isolated from barley as a tool for managing the cowpea bruchid, C. maculatus. PMID:25752426

  7. Ultrastructure of the spermatozoon of the digenean Tergestia acanthocephala (Stossich, 1887) (Gymnophalloidea: Fellodistomidae): An intestinal parasite of Belone belone gracilis (Pisces: Teleostei).

    PubMed

    Kacem, H; Ndiaye, P I; Neifar, L; Torres, J; Miquel, J

    2015-06-01

    The ultrastructural organization of the spermatozoon of the digenean Tergestia acanthocephala (Gymnophalloidea: Fellodistomidae) is described. Live digeneans were collected from Belone belone gracilis (Teleostei: Belonidae), caught off the Gulf of Gabs in Chebba (Tunisia). The mature spermatozoon of T. acanthocephala exhibits the general pattern described in numerous digeneans, characterized by the presence of two axonemes of the different length of the 9+'1' pattern of the Trepaxonemata, a nucleus, two mitochondria, two bundles of parallel cortical microtubules, external ornamentation, spine-like bodies and granules of glycogen. Moreover, the morphology of the posterior spermatozoon extremity in T. acanthocephala corresponds to the fasciolidean type of Quilichini et al. (2010a). PMID:25796547

  8. Import of exotic and zoonotic trematodes (Heterophyidae: Centrocestus sp.) in Xiphophorus maculatus: implications for ornamental fish import control in Europe.

    PubMed

    Mehrdana, Foojan; Jensen, Hannah M; Kania, Per W; Buchmann, Kurt

    2014-06-01

    Ornamental fish, Xiphophorus maculatus, were imported from Singapore to Denmark for distribution to local aquarists. Importers observed lethargic and erratic swimming patterns among fish and forwarded a total of 30 fish for pathological examination to a university diagnostic service. All fish were diagnosed infected with encysted Centrocestus sp. metacercariae in gills (prevalence of 100% and mean intensity of 454.5 161.9 parasites per fish). Metacercariae were identified by morphological and molecular methods. Cysts (mean length 163.3 13.7 ?m and mean width 113.3 10.6 ?m) contained a bent metacercaria with an X-shaped excretory bladder. PCR amplification of a rDNA region (5.8S rRNA gene, ITS-2, 28S rRNA gene) and subsequent sequencing confirmed the diagnosis. Metacercariae were found in gill filaments adjacent to the cartilage associated with cartilage hypertrophy, epithelial and mucous cell hyperplasia, clubbing and lamellar fusion. Host cell encapsulation of cysts comprised several layers of leucocytes, chondroblast-like and fibroblast-like cells. The observations raise concerns with regard to veterinary inspection and quarantine procedures. The zoonotic potential of these trematodes and a possible spread of the parasites in natural habitats in Europe should be regarded as a public health issue. So far, several cases of human infections have been reported only in Asia, but the potential intermediate host snail, Melanoides tuberculata, has been recorded in Germany. Accordingly, establishment of the parasite in Europe with climate changes should be considered a risk. PMID:24827099

  9. Developmental temperature affects the expression of ejaculatory traits and the outcome of sperm competition in Callosobruchus maculatus.

    PubMed

    Vasudeva, R; Deeming, D C; Eady, P E

    2014-09-01

    The outcome of post-copulatory sexual selection is determined by a complex set of interactions between the primary reproductive traits of two or more males and their interactions with the reproductive traits of the female. Recently, a number of studies have shown the primary reproductive traits of both males and females express phenotypic plasticity in response to the thermal environment experienced during ontogeny. However, how plasticity in these traits affects the dynamics of sperm competition remains largely unknown. Here, we demonstrate plasticity in testes size, sperm size and sperm number in response to developmental temperature in the bruchid beetle Callosobruchus maculatus. Males reared at the highest temperature eclosed at the smallest body size and had the smallest absolute and relative testes size. Males reared at both the high- and low-temperature extremes produced both fewer and smaller sperm than males reared at intermediate temperatures. In the absence of sperm competition, developmental temperature had no effect on male fertility. However, under conditions of sperm competition, males reared at either temperature extreme were less competitive in terms of sperm offence (P(2)), whereas those reared at the lowest temperature were less competitive in terms of sperm defence (P(1)). This suggests the developmental pathways that regulate the phenotypic expression of these ejaculatory traits are subject to both natural and sexual selection: natural selection in the pre-ejaculatory environment and sexual selection in the post-ejaculatory environment. In nature, thermal heterogeneity during development is commonplace. Therefore, we suggest the interplay between ecology and development represents an important, yet hitherto underestimated component of male fitness via post-copulatory sexual selection. PMID:24891122

  10. Extracellular matrix remodeling of the testes through the male reproductive cycle in Teleostei fish.

    PubMed

    Santana, Julio Cesar de Oliveira; Quagio-Grassiotto, Irani

    2014-12-01

    During the fish reproductive cycle, testes undergo morphological changes related to germinal epithelium and remodeling of extracellular matrix components (ECM). ECM is degraded mainly by action of matrix metalloproteinases (MMPs). Due to the natural renewal of ECM in fish testes, we choose Pimelodus maculatus to study remodeling of ECM throughout reproductive cycle, using picrosirius (to identify type I, II, III collagen) and reticulin (type III collagen), and to immunolocalize MT1-MMP (membrane type 1-matrix metalloproteinase) and MMP-2 in testis cells. Testes were classified in four reproductive phases: regenerating, development, spawning capable and regressing. Picrosirius and reticulin demonstrated a differential distribution of total collagen fibers during the reproductive cycle. Immunohistochemistry showed MT1-MMP only in acidophilic granulocyte cells mainly inside blood vessels, in connective tissue of capsule close to the germinal compartment, and also infiltrated in interstitial connective tissue. MMP-2 was detected in fibroblast and endothelial cells of interstitial and capsule blood vessels, in epithelial cells of capsule, and in acidophilic granulocyte cells at same description for MT1-MMP. The fish testes ECM were remodeled throughout reproductive cycle in according to morphophysiological alterations. During reproductive season (spawning capable), the interstitium increased in total collagen fibers (type I, II, III). After spermiation period (regression and regenerating), the amount of collagen fibers decreased in response to action of MMPs on collagen degradation and other interstitial components (not assessed in this study). MMPs seem to be indispensable components for natural cyclic events of ECM remodeling of fish testes and for guarantee tissue homeostasis throughout reproductive cycle. PMID:25142725

  11. [The endoparasitic helminths of Pimelodus maculatus Lacpde, 1803 Siluriformes, Pimelodidae) from the two localities (Lagoon and gutter of the River) of the Guandu River, State of Rio de Janeiro, Brazil].

    PubMed

    Albuquerque, Marcia C; Santos, Michelle D; Monteiro, Cassandra M; Martins, Amanda N; Ederli, Nicole B; Brasil-Sato, Marilia C

    2008-09-01

    Between November 2003 and March 2004, fourty specimens of Pimelodus maculatus Lacpde, 1803 from Guandu River and thirty-nine from Guandu Lagoon (Nova Iguau, RJ) were collected, for the analysis of endoparasitic fauna. A total of 236 specimens of Cucullanus pinnai Travassos, Artigas & Pereira, 1928 (Nematoda, Cucullanidae) were collected, being 163 adult specimens in the gut, three in the stomach and 70 larvae in the celomatic cavity and seven specimens of adults Nomimoscolex sp. (Eucestoda, Proteocephalidea) in the gut were found. Cucullanus pinnai presented prevalence (P) 77.50%, mean intensity (MI) 3.40 and mean abundance (MA) 2.60 on River and P: 66.67%, MI: 5.04, MA: 3.36 on Lagoon. Nomimoscolex sp. presented on River P: 2.50%, MI: 2.00, MA: 0.05, and P: 10.26%, MI: 1.25, MA: 0.13 on Lagoon. There was not significant positive interspecific association on the lagoon. In this research, the endoparasitic richness of P. maculatus was scarcest than similar studies in Guandu River and others rivers of different basins. The results about C. pinnai could be suggesting that the cycle of C. pinnai evolve only a host, occurring a histotrophic fase, in this case, in P. maculatus. Periodic analysis of the endoparasites indices in P. maculatus through the years may be used to describe the hydric quality of the Guandu River. PMID:20059829

  12. Vicilin-derived peptides are transferred from males to females as seminal nuptial gift in the seed-feeding beetle Callosobruchus maculatus.

    PubMed

    Alexandre, Daniel; Linhares, Ricardo T; Queiroz, Bruna; Fontoura, Luisa; Ucha, Adriana F; Samuels, Richard I; Macedo, Maria Lgia R; Bezerra, Cezar S; Oliveira, Eliana M; Demartini, Diogo R; Carlini, Clia R; Silva, Carlos P

    2011-06-01

    The fate of vicilins ingested by Callosobruchus maculatus and the physiological importance of these proteins in larvae and adults have been recently investigated. Vicilins have been demonstrated to be absorbed through the midgut epithelium, circulate in their trimeric form in the haemolymph and are deposited in the fat body. In fat body cells of both sexes, vicilins are partially hydrolyzed and the fragments are eventually deposited in the eggs. Tracking the fate of FITC-labelled vicilins in adult males revealed that the labelled vicilin fragments were also detected in ocytes and eggs, when the males copulated with non-labelled females. Based on the results presented here, we propose that following absorption, vicilins accumulate in the fat body, where they are partially degraded. These peptides are retained throughout the development of the males and are eventually sequestered by the gonads and passed to the female gonads during copulation. It is possible that accumulation in the eggs is a defensive strategy against pathogen attack, as these peptides are known to have antimicrobial activity. The contribution of vicilin-derived peptides from seminal fluids may be an investment that helps to increase the offspring survival. This study provides additional insights into the possible contributions of males to female fecundity following copulation in C. maculatus. PMID:21420973

  13. Identification of Albizia lebbeck seed coat chitin-binding vicilins (7S globulins) with high toxicity to the larvae of the bruchid Callosobruchus maculatus

    PubMed Central

    Souza, A.J.; Ferreira, A.T.S.; Perales, J.; Beghini, D.G.; Fernandes, K.V.S.; Xavier-Filho, J.; Venancio, T.M.; Oliveira, A.E.A.

    2011-01-01

    Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitinbinding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1%, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78%. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation. PMID:22267002

  14. Convergent evolution of ecomorphological adaptations in geographically isolated Bay gobies (Teleostei: Gobionellidae) of the temperate North Pacific.

    PubMed

    Ellingson, Ryan A; Swift, Camm C; Findley, Lloyd T; Jacobs, David K

    2014-01-01

    North Pacific Bay gobies (Teleostei: Gobioidei: Gobionellidae) inhabit bays, beaches, coastal lagoons, and estuaries of temperate Asia and North America, but are absent from the boreal northernmost Pacific. Previously, morphological characters conventionally subdivided the clade into two groups - an elongate-bodied, infaunal-inhabiting "Astrabe" group, and a deeper-bodied, non-infaunal "Chasmichthys" group - each with a disjunct East-West (amphi-) Pacific distribution. Here we use mitochondrial and multi-locus nuclear DNA sequence data to show that several morphological characters previously used to delimit these two groups have in fact arisen independently on both sides of the Pacific, revealing convergence of ecologically adaptive characters within a geographically divided clade. Basal divergence of the resultant tree coincides with a dramatic global cooling event at the Eocene/Oligocene transition, without evidence of subsequent trans-Pacific migration. A novel approach to partitioning sequence data by relative rate, as opposed to traditional gene/codon position partitioning, was used to help distinguish phylogenetic signal from noise on a per-site basis. Resulting improvements in topology and nodal support, along with decreased computational effort, suggest that this partitioning strategy may be useful for future studies in phylogenetics and phylogenomics. PMID:24148989

  15. Molecular taxonomy and identification within the Antarctic genus Trematomus (Notothenioidei, Teleostei): How valuable is barcoding with COI?

    NASA Astrophysics Data System (ADS)

    Lautredou, A.-C.; Bonillo, C.; Denys, G.; Cruaud, C.; Ozouf-Costaz, C.; Lecointre, G.; Dettai, A.

    2010-08-01

    The Trematominae are a particularly interesting subfamily within the antarctic suborder Notothenioidei (Teleostei). The 14 closely related species occupy a large range of ecological of niches, extremely useful for evolutionary and biogeography studies in the Antarctic Ocean. But some Trematomus species can be difficult to identify by using morphological criteria, specially young stages and damaged specimens. Molecular identification would therefore be highly useful, however the suitability of the cytochrome oxidase I gene in a barcoding approach needs to be assessed. We evaluated species delineation within the genus Trematomus comparing morphological identification, nuclear markers (the rhodopsin retrogene and a new nuclear marker pkd1: polycystic kidney disease 1) and COI. We show that Trematomus vicarius is not distinguishable from Trematomus bernacchii with the molecular markers used, and neither is Trematomus loennbergii from Trematomus lepidorhinus. We suggest that until this is investigated further, studies including these species list them as T. loennbergii/ T. lepidorhinus group, and keep voucher samples and specimens. Generally, COI gives a congruent result with the rhodopsin retrogene, and except for the previously cited species pairs, COI barcoding is efficient for identification in this group. Moreover pkd1 might not be suitable for a phylogenetic study at this scale for this group.

  16. Analysis of the morphogenesis and cell proliferation in the retina of a pleuronectiform fish, the turbot Psetta maxima (Pleuronectiformes: Teleostei).

    PubMed

    Cid, Patricia; Doldn, Mara Jess; Rodrguez, Mara Soledad; Prego, Benjamin; de Miguel, Encarnacin

    2013-06-01

    The morphogenesis and cell proliferation in the retina of turbot (Psetta maxima, Pleuronectiformes: Teleostei) from embryo through metamorphosis have been examined by using proliferating cell nuclear antigen (PCNA)-immunohistochemistry and general histological procedures. In the embryonic retina, cell proliferation and spatial cell reorganization form the anlage of the pigment epithelium and neural retina. Neurogenesis begins around hatching in the temporal retina, dorsal to the optic nerve exit, and then a wave of cell differentiation spreads to the nasal retina to yield a laminated retina by the end of the prolarval turbot stage. Germinal zones in the differentiated retina persist as a rim at the retinal margin, as well as surrounding the optic fissure in premetamorphic and metamorphic turbot larvae. In these zones, progenitor cells with different morphologies show a similar spatial arrangement, which suggests that they have a similar retinogenic potential. During metamorphosis, asymmetric proliferative activity in turbot germinal zones is associated with a marked expansion of the retinal tissue. Scattered stem cells in the laminated retina, related to the lineage of rod photoreceptors, were also observed both in large premetamorphic larvae and metamorphic turbots. The proliferative activity of these cells increases considerably during metamorphosis, when rod photoreceptors become morphologically differentiated. PMID:23495202

  17. A new variant of antimetabolic protein, arcelin from an Indian bean, Lablab purpureus (Linn.) and its effect on the stored product pest, Callosobruchus maculatus.

    PubMed

    Janarthanan, Sundaram; Sakthivelkumar, Shanmugavel; Veeramani, Velayutham; Radhika, Dixit; Muthukrishanan, Subbaratnam

    2012-12-15

    The anti-metabolic or insecticidal gene, arcelin (Arl) was isolated, cloned and sequenced using sequence specific degenerate primers from the seeds of Lablab purpureus collected from the Western Ghats, Tamil Nadu, India. The L. purpureus arcelin nucleotide sequence was homologous to Arl-3 and Arl-4 alleles from Phaseolus spp. The protein it encodes has 70% amino acid identity with the amino acid sequences of Arl-3I, Arl-3III, Arl-4 precursor, Arl-4 and Arl-4I. The partially purified arcelin from the seeds of L. purpureus using an artificial diet confirmed the complete retardation of development of the stored product pest Callosobruchus maculatus at 0.2% w/w arcelin-incorporated artificial seeds. PMID:22980880

  18. A review of Galaxiella pusilla (Mack) (Teleostei: Galaxiidae) in south-eastern Australia with a description of a new species.

    PubMed

    Coleman, Rhys A; Hoffmann, Ary A; Raadik, Tarmo A

    2015-01-01

    The dwarf galaxias, Galaxiella pusilla (Mack), is a small, threatened freshwater fish from coastal south-eastern Australia. Recent genetic studies, using multiple nuclear and mitochondrial DNA markers, found substantial differences between populations in western Victoria and south Australia ('west region') compared to eastern Victoria, Flinders Island, and Tasmania ('east region') that suggest the presence of a cryptic species. Morphological measurements and meristic counts from multiple populations within each region were undertaken to investigate potential differences between regions. Several characters, found to discriminate between individuals in the regions and to be diagnostic for two taxa, were used to describe a new species, Galaxiella toourtkoourt, for the west region. This is only the second species in the Galaxiidae to exhibit sexual dimorphism. The original description of Galaxiella pusilla, based on five specimens, is revised following examination of a large number of individuals. Both species are considered nationally threatened and are categorised as 'endangered'; the revised distribution of G. pusilla s.s. is reduced by approximately 60%. A number of inconsistencies in the most recent revision of the genus Galaxiella are also corrected. PMID:26624129

  19. Cytomorphological alterations of the thymus, spleen, head-kidney, and liver in cardinal fish (Apogonidae, Teleostei) as bioindicators of stress.

    PubMed

    Fishelson, Lev

    2006-01-01

    Morphological and cytological alterations at the light microscope (LM) and transmission electron microscope (TEM) levels were observed in the thymus, spleen, head-kidney, and liver of cardinal fishes (Apogonidae, Teleostei) from the Gulf of Aqaba, Red Sea, sampled from a strongly polluted site at the northern end of the gulf, and compared to similar samples from a clean, reference site. At the polluted site, the most prominent change was the formation of numerous deposits of cells rich in phagosomes with lipofucin, melanin granules, and phagocytosed debris, including a high increase in number and dimensions of Hassall's corpuscles and melano-macrophage centers. The number of Hassall's corpuscles was 20 (+/-8.0)/mm(2) and of melano-macrophage centers 18 (+/-4.0)/mm(2) at the polluted site, and 7.0 (+/-4.0)/m(2) vs. 5.0 (+/-2.0)/mm(2) respectively at the reference site. In numerous instances the head kidney's melano-macrophage centers in fishes from the polluted site were encapsulated by reticulocytes, a phenomenon recognized as a marker of neoplasmosis and possible malignancy. In the spleens of fishes from the polluted site, numerous deposits of cell debris, peroxisomes, and enlarged lysosomes were also observed. The livers (hepatopancreas) of fishes from polluted waters demonstrated very strong hyperlipogeny. Many of their hepatocytes were laden with lipid vesicles, fragmented endoplasmic reticulula, and aberrant mitochondria. Although the observed alterations in the glands and liver do not indicate any immediate threat to the life of the fish, they can become crucial with respect to energy turnover and fecundity trajectories. This study strongly suggests the use of cytological alterations in vital organs, such as were observed, as pathological biomarkers to environmental stress. PMID:16247768

  20. Four new species of Cichlidogyrus (Monogenea, Ancyrocephalidae) from Sarotherodon mvogoi and Tylochromis sudanensis (Teleostei, Cichlidae) in Cameroon.

    PubMed

    Pariselle, Antoine; Nyom, Arnold R Bitja; Bilong, Charles F Bilong

    2014-01-01

    The four Cichlidogyrus species (Monogenea, Ancyrocephalidae) found on the gills of Sarotherodon mvogoi and Tylochromis sudanensis (Teleostei, Cichlidae) in Cameroon are considered new and are described herein. Cichlidogyrus mvogoi n. sp. from Sarotherodon mvogoi, characterised by a long (> 100 m), thin and spirally coiled penis and a short marginal hook pair I. Cichlidogyrus sigmocirrus n. sp. from Tylochromis sudanensis, characterised by a short marginal hook pair I, a slightly spirally coiled penis with reduced heel, an accessory piece being a spirally coiled band wrapped round the penis and attached to the penis basal bulb by a very thin filament. Cichlidogyrus chrysopiformis n. sp. from Tylochromis sudanensis, characterised by an marginal hook pair I of medium size, a thin spirally coiled penis (1.5 turn) with a developed flared heel, an accessory piece being a large gutter shaped band, ending in a narrow complex extremity, and linked to the basal bulb of the penis by a very thin filament, a short, straight and slightly ringed vagina. Cichlidogyrus djietoi n. sp. from Tylochromis sudanensis, characterised by a slightly spirally coiled penis (2 turns) with developed heel, an accessory piece being a large gutter shaped band, ending in a narrow folded back extremity, a short funnel shaped vagina. The three latter species are also remarkable by the morphology of their auricles implanted on the anterior side of the dorsal transverse bar which make them (together with the other species described from Tylochromis hosts) a homogeneous and original group within Cichlidogyrus, this distinctive feature seems to be ancestral compared to other Cichlidogyrus species. PMID:25543634

  1. Phylogeny and biogeography of highly diverged freshwater fish species (Leuciscinae, Cyprinidae, Teleostei) inferred from mitochondrial genome analysis.

    PubMed

    Imoto, Junichi M; Saitoh, Kenji; Sasaki, Takeshi; Yonezawa, Takahiro; Adachi, Jun; Kartavtsev, Yuri P; Miya, Masaki; Nishida, Mutsumi; Hanzawa, Naoto

    2013-02-10

    The distribution of freshwater taxa is a good biogeographic model to study pattern and process of vicariance and dispersal. The subfamily Leuciscinae (Cyprinidae, Teleostei) consists of many species distributed widely in Eurasia and North America. Leuciscinae have been divided into two phyletic groups, leuciscin and phoxinin. The phylogenetic relationships between major clades within the subfamily are poorly understood, largely because of the overwhelming diversity of the group. The origin of the Far Eastern phoxinin is an interesting question regarding the evolutionary history of Leuciscinae. Here we present phylogenetic analysis of 31 species of Leuciscinae and outgroups based on complete mitochondrial genome sequences to clarify the phylogenetic relationships and to infer the evolutionary history of the subfamily. Phylogenetic analysis suggests that the Far Eastern phoxinin species comprised the monophyletic clades Tribolodon, Pseudaspius, Oreoleuciscus and Far Eastern Phoxinus. The Far Eastern phoxinin clade was independent of other Leuciscinae lineages and was closer to North American phoxinins than European leuciscins. All of our analysis also suggested that leuciscins and phoxinins each constituted monophyletic groups. Divergence time estimation suggested that Leuciscinae species diverged from outgroups such as Tincinae to be 83.3 million years ago (Mya) in the Late Cretaceous and leuciscin and phoxinin shared a common ancestor 70.7 Mya. Radiation of Leuciscinae lineages occurred during the Late Cretaceous to Paleocene. This period also witnessed the radiation of tetrapods. Reconstruction of ancestral areas indicates Leuciscinae species originated within Europe. Leuciscin species evolved in Europe and the ancestor of phoxinin was distributed in North America. The Far Eastern phoxinins would have dispersed from North America to Far East across the Beringia land bridge. The present study suggests important roles for the continental rearrangements during the Late Cretaceous to form the present-day distribution of organisms. Furthermore, the Late Cretaceous biotic turnover influenced for the modern terrestrial biodiversity. PMID:23174367

  2. Repellent activity of some essential oils against two stored product beetles Callosobruchus chinensis L. and C. maculatus F. (Coleoptera: Bruchidae) with reference to Chenopodium ambrosioides L. oil for the safety of pigeon pea seeds.

    PubMed

    Pandey, Abhay K; Palni, Uma T; Tripathi, N N

    2014-12-01

    Essential oils from 35 aromatic and medicinal plant species of Gorakhpur Division (U. P., India) were evaluated for their repellent activity against pulse bruchids Callosobruchus chinensis L. and C. maculatus F. of stored pigeon pea seeds. The oil concentration was at 0.36?l/ml. Out of 35 essential oils, Adhatoda vasica Ness and Chenopodium ambrosioides L. oils showed absolute (100%) insect repellency. Chenopodium oil exhibited 100% mortality for both the test insects at 10?l concentration (LD50?=?2.8?l for C. chinensis & 2.5?l for C. maculatus) and more toxic than Adhatoda oil (LD50?=?6.8?l for C. chinensis & 8.4?l for C. maculatus). During in vivo evaluation, 0.29 and 0.58?l/ml of Chenopodium oil significantly enhanced feeding deterrence in insects and reduced the seed damage as well as weight loss of fumigated pigeon pea seeds up to 6months of storage as compared to control set. Thus, Chenopodium oil can be used as an effective option of commercial fumigants for the storage of pigeon pea seeds against pulse bruchids. PMID:25477682

  3. Comparative morphology of the gonadal structure related to reproductive strategies in six species of neotropical catfishes (Teleostei: Siluriformes).

    PubMed

    Melo, Rafael Magno Costa; Arantes, Fbio Pereira; Sato, Yoshimi; dos Santos, Jos Enemir; Rizzo, Elizete; Bazzoli, Nilo

    2011-05-01

    We studied the relationship between the morphology of the reproductive system and the reproductive strategies of six neotropical catfishes using macroscopic and microscopic analyses. The reproductive system of the examined Siluriformes showed diversified characteristics, but permitted their being grouped according to three reproductive strategies: pelagic spawning, demersal spawning, and internally fertilizing. The pelagic spawners Pseudoplatystoma corruscans and Conorhynchos conirostris have testes that are characterized by filiform lobes, absence of testicular secretion, full-grown oocytes of small diameter, thin zona radiata, and cuboidal follicular cells. Pimelodus maculatus is morphologically distinct from the other two pelagic spawners catfishes due to the presence of testicular secretion. The demersal spawners Lophiosilurus alexandri and Rhinelepis aspera possess homogeneous testicular secretion, large mature oocytes, and columnar follicular cells. The most specialized reproductive system was observed in the internally fertilizing Trachelyopterus galeatus, which possesses a seminal vesicle accessory to the testes, spermatozoa with elongated nuclei that form spermatozeugmata, and a secretory ovarian lamellar epithelium that is associated with sperm storage. The reproductive system observed in Neotropical catfishes showed a relationship associated with the type of fertilization and the reproductive strategies of the six species studied. PMID:21246599

  4. First report of toxicity of Xylopiaparviflora (A. Rich.) Benth (Annonaceae) root bark's essential oil against cowpea seed bruchid, Callososbruchus maculatus Fabricius (Coleoptera: Chrysomelidae: Bruchinae).

    PubMed

    Babarinde, Samuel Adelani; Pitan, Olufemi Olutoyin Richard; Olatunde, Ganiyu Olatunji; Ajala, Michael Oluwole

    2015-01-01

    The fumigant toxicity of Xylopia parviflora (A. Rich.) Benth (Annonaceae) root bark's essential oil (EO) against cowpea seed bruchid, Callosobruchus maculatus, was investigated in the laboratory. Dose had significant (P < 0.0001) effect on mortality at 6 hours after treatment (HAT) at a concentration of 6.25 ?L/mL air which exerted 81.70% mortality, while there was no mortality in all other lower doses. At 12 HAT, 75.05% and 90.00% mortality were observed at doses of 3.15 and 6.25 ?L/mL air, respectively. It was significantly (P < 0.05) higher than the mortality (50.58%) observed when 0.78 ?L/mL air was applied. The lethal time for 50% of assayed adults (LT50) obtained when the bruchid was exposed to X. parviflora EO at a dose of 6.25 ?L/mL air (2.71 h) was significantly lower than LT50 obtained at exposure of bruchid to other lower doses of 0.78-3.15 ?L/mL air. PMID:25105241

  5. Insecticide Activity of Essential Oils of Mentha longifolia, Pulicaria gnaphalodes and Achillea wilhelmsii Against Two Stored Product Pests, the Flour Beetle, Tribolium castaneum, and the Cowpea Weevil, Callosobruchus maculatus

    PubMed Central

    Khani, Abbas; Asghari, Javad

    2012-01-01

    Essential oils extracted from the foliage of Mentha longifolia (L.) (Lamiales: Lamiaceae) and Pulicaria gnaphalodes Ventenat (Asterales: Asteraceae), and flowers of Achillea wilhelmsii C. Koch (Asterales: Asteraceae) were tested in the laboratory for volatile toxicity against two storedproduct insects, the flour beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) and the cowpea weevil, Callosobruchus maculatus F. (Coleoptera: Bruchidae). The chemical composition of the isolated oils was examined by gas chromatography-mass spectrometry. InM longifolia, the major compounds were piperitenon (43.9%), tripal (14.3%), oxathiane (9.3%), piperiton oxide (5.9%), and d-limonene (4.3%). In P. gnaphalodes, the major compounds were chrysanthenyl acetate (22.38%), 2L -4L-dihydroxy eicosane (18.5%), verbenol (16.59%), dehydroaromadendrene (12.54%), β-pinen (6.43%), and 1,8 cineol (5.6%). In A. wilhelmsii, the major compounds were 1,8 cineole (13.03%), caranol (8.26%), alpha pinene (6%), farnesyl acetate (6%), and p-cymene (6%). C maculatus was more susceptible to the tested plant products than T castaneum. The oils of the three plants displayed the same insecticidal activity against C. maculatus based on LC50 values (between 1.54µl/L air in P. gnaphalodes, and 2.65 µl/L air in A. wilhelmsii). While the oils of A. wilhelmsii and M. longifolia showed the same strong insecticidal activity against T. castaneum (LC50 = 10.02 and 13.05 µl/L air, respectively), the oil of P. gnaphalodes revealed poor activity against the insect (LC50 = 297.9 µl/L air). These results suggested that essential oils from the tested plants could be used as potential control agents for stored-product insects. PMID:23413994

  6. Protecting embryos from stress: Corticosterone effects and the corticosterone response to capture and confinement during pregnancy in a live-bearing lizard (Hoplodactylus maculatus)

    USGS Publications Warehouse

    Cree, A.; Tyrrell, C.L.; Preest, M.R.; Thorburn, D.; Guillette, L.J., Jr.

    2003-01-01

    Hormones in the embryonic environment, including those of the hypothalamo-pituitary-adrenal (HPA) axis, have profound effects on development in eutherian mammals. However, little is known about their effects in reptiles that have independently evolved viviparity. We investigated whether exogenous corticosterone affected embryonic development in the viviparous gecko Hoplodactylus maculatus, and whether pregnant geckos have a corticosterone response to capture and confinement that is suppressed relative to that in non-pregnant (vitellogenic) females and males. Corticosterone implants (5 mg, slow-release) administered to females in mid-pregnancy caused a large elevation of corticosterone in maternal plasma (P<0.001), probable reductions in embryonic growth and development (P=0.069-0.073), developmental abnormalities and eventual abortions. Cool temperature produced similar reductions in embryonic growth and development (P???0.036 cf. warm controls), but pregnancies were eventually successful. Despite the potentially harmful effects of elevated plasma corticosterone, pregnant females did not suppress their corticosterone response to capture and confinement relative to vitellogenic females, and both groups of females had higher responses than males. Future research should address whether lower maternal doses of corticosterone produce non-lethal effects on development that could contribute to phenotypic plasticity. Corticosterone implants also led to increased basking in pregnant females (P<0.001), and basal corticosterone in wild geckos (independent of reproductive condition) was positively correlated with body temperature (P<0.001). Interactions between temperature and corticosterone may have broad significance to other terrestrial ectotherms, and body temperature should be considered as a variable influencing plasma corticosterone concentrations in all future studies on reptiles. ?? 2003 Elsevier Inc. All rights reserved.

  7. Effects of insecticide formulations used in cotton cultivation in West Africa on the development of flat-backed toad tadpoles (Amietophrynus maculatus).

    PubMed

    Stechert, Christin; Kolb, Marit; Rödel, Mark-Oliver; Bahadir, Müfit

    2015-02-01

    In the West African savanna zone, traditional subsistence farming increasingly shifts to cash crop farming and in particular to cotton cultivation, which is accompanied by application of pesticides. Increasing use of pesticides by smallholder farmers is suspected to have negative effects on non-target organisms. In this study, possible pesticide impact on the development of tadpoles was investigated. Two insecticide formulations used in cotton cultivation in Benin were compared: Cotofan® (active ingredient (a.i.): α- and β-endosulfan) and Tihan® (a.i.: spirotetramat and flubendiamide). Tadpoles of the widespread species Amietophrynus maculatus were kept in small water basins with increasing insecticide concentrations (1, 10 and 100 μg a.i./L) over a period of 28 days. Tadpoles showed reduced survival at the highest endosulfan concentrations (100 μg/L). Survival of tadpoles undergoing metamorphosis was not influenced by Tihan®. Endosulfan in concentrations of 10 and 100 μg/L negatively impacted the movement of the tadpoles which was not the case for the mixture of spirotetramat and flubendiamide. Time to metamorphosis was not significantly different in the various treatments. Tail length of tadpoles was significantly shorter in Cotofan® treatments compared to controls. Pesticide residues in the tadpoles were relatively low after keeping them in concentrations of 1 and 10 μg a.i./L (25 and 26 μg/kg wet weight (w/w) for the sum of α-endosulfan, β-endosulfan and endosulfan sulphate and below the detection limits for flubendiamide and spirotetramat). For the 100 μg a.i./L treatments, 1,600 μg/kg w/w was found of α-endosulfan, β-endosulfan and endosulfan sulphate together in the survived tadpoles and 21 μg/kg w/w of flubendiamide. PMID:25192667

  8. Evolucin de galaxias y QSOs Modelo evolutivo-explosivo-compuesto: fase final de galaxias y origen explosivo de galaxias enanas

    NASA Astrophysics Data System (ADS)

    Lpari, S. L.; Terlevich, R. J.; Taniguchi, Y.; Mediavilla, E.; Bergmann, M.; Garca-Lorenzo, B.; Snchez, S. F.; Zheng, W.; Punsly, B.; Merlo, D. C.

    2015-08-01

    We present new results of our evolutionary-explosive- composite model of Galaxies, Quasars and AGNs. In particular: we explain the concept of final phase of a galaxy and the fact that at least a fraction of dwarf galaxies can be explained by this model (as a stage prior to the final). In addition, we explain that the prototype of the starburst galaxy M82 could be a dwarf galaxy previous to the final phase. Also, we discuss new Gemini observations BAL + FeII + IR medium-high redshift QSOs. To interpret these results we performed an introduction to our model and some of the most previous relevant results, including: (i) Evolution Diagram of Galaxies, QSOs and AGNs; (ii) Our Evolutionary-Explosive-Compound Model explains in the same process: the interaction of ``Starburst'' and Supermassive black holes that generate hypernova, the Origin of Ultra Energetic Cosmic Rays and Dark Matter. (iii) Observation and Theory of Formation and Final Phase of Galaxies via hypernova explosions in QSOs and AGNs.

  9. Performance of bean bruchids Callosobruchus maculatus and Zabrotes subfasciatus (Coleoptera: Bruchidae) reared on resistant (IT81D-1045) and susceptible (Epace 10) Vigna unguiculata seeds: relationship with trypsin inhibitor and vicilin excretion.

    PubMed

    Sales, M P; Andrade, L B S; Ary, M B; Miranda, M R A; Teixeira, F M; Oliveira, A S; Fernandes, K V S; Xavier-Filho, J

    2005-12-01

    Callosobruchus maculatus (Cm) and Zabrotes subfasciatus (Zs) were reared on resistant (IT81D-1045) and on susceptible (Epace 10) cowpea seeds. The emergence of adult insects, total developmental period (TDP) and excretion of trypsin inhibitor and vicilin were determined for both bruchid populations. Parameter evaluation showed that the Zs populations emerged from both seeds had no significant differences in emergence and TDP. The Cm population raised from resistant seeds had lower emergence (5.6+/-1.3%) and delayed TDP (46+/-1.25 days) than those emerged from susceptible seeds. The excretion of defense proteins showed that Zs reared in resistant seeds excreted 1.7 times more trypsin inhibitor, but this did not affect emergence or TDP. Furthermore, Cm population emerged from resistant seeds excreted 7 times higher vicilin and 0.4 times less trypsin inhibitor than that emerged from susceptible seeds. These results indicate that vicilins from resistant seeds are involved to significantly longer TDP (46 days) and also drastic reduction of insect emergence ( approximately 5%) of C. maculatus. PMID:16246611

  10. Seven-locus molecular phylogeny of Myctophiformes (Teleostei; Scopelomorpha) highlights the utility of the order for studies of deep-sea evolution.

    PubMed

    Denton, John S S

    2014-07-01

    Fishes of the order Myctophiformes (Teleostei; Scopelomorpha) comprise over half of all deep-sea biomass, and are a critical component of marine ecosystems worldwide. Members of the family Myctophidae, within Myctophiformes, form the majority of species diversity within the order (?250 species, 33 genera, 2 subfamilies), and are further known for their diverse bioluminescent traits, comprised of distinct cranial, postcranial, and caudal luminous systems that is perhaps the most elaborate among all vertebrates. These features make myctophids particularly compelling from both economic and scientific perspectives, yet no studies have sampled these fishes at a density appropriate for addressing any questions requiring a phylogenetic hypothesis as input. This study therefore presents a seven-locus molecular phylogeny of the order, sampling over 50% of all nominal myctophid species. This taxon sampling triples the representation of the next most comprehensive analysis, and reveals several new and well-supported hypotheses of relationships, in addition to supporting traditional hypotheses based on combined morphological data. This analysis shows that the slendertailed myctophids Gonichthys, Centrobranchus, Loweina, and Tarletonbeania are rendered non-monophyletic by a polyphyletic Myctophum; the enigmatic, monotypic genus Notolychnus valdiviae is nested within tribe Lampanyctini; the genus Diaphus is divided into at least two clades, with the suborbital (So) group recovered as monophyletic with strong support; and the genera Lampanyctus and Nannobrachium are recovered as non-monophyletic. These molecular results highlight the potential of myctophids as a premier model system for the application of modern comparative methods to studies of deep-sea evolution. PMID:24583290

  11. Diversification of substrate specificities in teleostei Fads2: characterization of Δ4 and Δ6Δ5 desaturases of Chirostoma estor[S

    PubMed Central

    Fonseca-Madrigal, Jorge; Navarro, Juan C.; Hontoria, Francisco; Tocher, Douglas R.; Martínez-Palacios, Carlos A.; Monroig, Óscar

    2014-01-01

    Currently existing data show that the capability for long-chain PUFA (LC-PUFA) biosynthesis in teleost fish is more diverse than in other vertebrates. Such diversity has been primarily linked to the subfunctionalization that teleostei fatty acyl desaturase (Fads)2 desaturases have undergone during evolution. We previously showed that Chirostoma estor, one of the few representatives of freshwater atherinopsids, had the ability for LC-PUFA biosynthesis from C18 PUFA precursors, in agreement with this species having unusually high contents of DHA. The particular ancestry and pattern of LC-PUFA biosynthesis activity of C. estor make this species an excellent model for study to gain further insight into LC-PUFA biosynthetic abilities among teleosts. The present study aimed to characterize cDNA sequences encoding fatty acyl elongases and desaturases, key genes involved in the LC-PUFA biosynthesis. Results show that C. estor expresses an elongase of very long-chain FA (Elovl)5 elongase and two Fads2 desaturases displaying Δ4 and Δ6/Δ5 specificities, thus allowing us to conclude that these three genes cover all the enzymatic abilities required for LC-PUFA biosynthesis from C18 PUFA. In addition, the specificities of the C. estor Fads2 enabled us to propose potential evolutionary patterns and mechanisms for subfunctionalization of Fads2 among fish lineages. PMID:24792929

  12. Ultrastructural and Phylogenetic Description of Kudoa orbicularis n. sp. (Myxosporea: Multivalvulida): A Parasite Infecting the Muscle of the Fish Chaetobranchopsis orbicularis (Teleostei: Cichlidae) in the Amazon Region.

    PubMed

    Azevedo, Carlos; Rocha, Snia; Matos, Edilson; Oliveira, Elsa; Matos, Patrcia; Al-Quraishy, Saleh; Casal, Graa

    2016-01-01

    A new myxosporean species is described from the muscle of the Amazonian freshwater fish Chaetobranchopsis orbicularis (Teleostei, Cichlidae), with basis on morphometric, ultrastructural and molecular data. Numerous myxospores were observed within pseudocysts located on the hosts' dorsal and ventral muscles, near the neural spines and neural canal (spinal cord). Mature myxospores quadrangular with rounded ends in apical view, measuring 4.3 (3.6-5.0)?m in length and 5.1 (4.2-5.8)?m in width. The myxospores wall is formed by four symmetric valves. Within, four pyriform polar capsules, 2.1 (1.7-2.6)?m long and 1.3 (0.9-1.7)?m wide, located two by two in opposite sides of the myxospores longitudinal axis, each containing a polar filament forming 2-3 coils. Molecular analysis of the SSU rRNA gene by maximum likelihood, neighbor-joining and maximum parsimony confirms the parasite as a new member of the genus Kudoa, herein named Kudoa orbicularis n. sp., the second species of its genus reported from the South American freshwater fauna, and the fourth species worldwide known to occur in the freshwater environment. Furthermore, its sequence of the SSU rRNA gene constitutes the first entry of a freshwater Kudoa species in GenBank. PMID:26095978

  13. Simulaciones de formacin de galaxias disco barreadas

    NASA Astrophysics Data System (ADS)

    Algorry, D. G.; Abadi, M. G.; Ferrero, I.

    2015-08-01

    In this work we present a study of the formation and evolution of two galaxies selected from a series of numerical cosmological hydrodynamical simulations called GIMIC. The first one is a galaxy with a central bar at redshift z = 0 formed between 9 t [Gyr] 11. At this time, the galaxy accretes gas from distinct directions forming a ring located in a different plane respect to the galaxy disc. This disc transfers its angular momentum to the gas and halo decaying its pattern speed and becoming a bar. The second one is a galaxy that had a bar until a time t 10 Gyr. After this time, the bar gradually disintegrate until redshift z = 0 (t = 13.6 Gyr). This disintegration is unusual and may be due to strong perturbations originated by the proximity of a massive satellite at t 10 Gyr.

  14. Las Galaxias Enanas y la Red Csmica

    NASA Astrophysics Data System (ADS)

    Bentez Llambay, A.; Abadi, M. G.

    Using a cosmological numerical simulation of the Local Group formation, we identify a mechanism able to remove gas from low-mass halos, affecting dramatically their star formation histories. As the Local Group forms, matter bound to it develops an intrincate network of filaments and pancakes, which sweeps a large volume, overtaking and removing the gas of several halos, leaving their dark matter component unaffected. The gas loss is particulary pronunced for low-mass halos, which may help to explain the scarcity of dwarf galaxies observed when compared to the large number of low-mass halos expected in the ?CDM cosmological model. FULL TEXT IN SPANISH

  15. Interacciones de galaxias: sistemas con puentes tidales

    NASA Astrophysics Data System (ADS)

    Mesa, V.; Alonso, S.; Duplancic, F.; Lambas, D. G.

    2015-08-01

    In this work we present a sample of interacting galaxy pairs connected by a bridge, obtained from a visual classification of a pair catalogue derived from the seventh data release of the Sloan Digital Sky Survey (SDSS-DR7). We present preliminary results of the general characteristics of galaxies in these systems, such as specific star formation rate, age of the stellar populations, concentration index, colour and local density environment.

  16. Catlogo de galaxias con ncleo doble

    NASA Astrophysics Data System (ADS)

    Gimeno, G.; Daz, R. J.; Carranza, G.

    Through systematic inspection of the publications in extragalactic astronomy and galaxy catalogs, we compiled a first list of spiral galaxies with double or multiple nucleus, confirmed and candidates (about 150 objects). This list includes, in its preliminar form, basic data on each object (Names, Coordinates, Redshift, Abs.Mag.B, Major and Minor Axes, Nuclei Separation, IR Properties, Comments, etc.) and for nuclei with apparent separations larger than 1'', it seems complete up to z = 0.0015. This allows us to analize the possible correlations between the geometric and photometric parameters of the double nuclei and the host galaxies, some of which are important, e.g.: nuclei separation vs. absolute magnitude and vs. host galaxy diameter; star formation rate vs. nuclei separation. We also find common global infrared an optical photometric properties that are beeing analized in order to check the validity of some models of galaxies captures and mergers. A subsample of southern objects included in this catalog is beeing observed at Bosque Alegre Astrophysical Station and, up to date, we have performed BVRI photometry and spectroscopy of twelve double or multiple nuclei galaxies.

  17. Integrative taxonomy identifies a new species of Phyllodistomum (Digenea: Gorgoderidae) from the twospot livebearer, Heterandria bimaculata (Teleostei: Poeciliidae), in Central Veracruz, Mexico.

    PubMed

    Razo-Mendivil, Ulises; Prez-Ponce de Len, Gerardo; Rubio-Godoy, Miguel

    2013-12-01

    Phyllodistomum inecoli n. sp. is described from the twospot livebearer, Heterandria bimaculata (Teleostei: Poeciliidae), collected in the Ro La Antigua basin, Veracruz, Mexico. The new species is described and characterised by using a combination of morphology, scanning electron microscopy, and sequences of nuclear and mitochondrial genes. Diagnostic characters of the new species of Phyllodistomum include a genital pore opening at the level of the caecal bifurcation; oval vitellarium, situated just posterior to the ventral sucker and not extended laterally and anterior extracaecal uterine loops variable in extension (reaching the anterior, median or posterior margin of the ventral sucker). P. inecoli n. sp. most closely resembles P. brevicecum, a species described as a parasite of the central mudminnow, Umbra limi, in other parts of North America; however, the genital pore in P. brevicecum is situated between the caecal bifurcation and the ventral sucker, the ovary is larger, the vitellarium is lobed and extended laterally and the anterior portion of the uterus extends to the posterior margin of the ventral sucker. Comparison of about 1,5002,200 nucleotides of cox1 and 28S rDNA and ITS1 strongly supports the status of P. inecoli as a new species. Bayesian inference analysis of combined datasets of 28S rDNA and cox1 sequences showed that P. inecoli n. sp. and the other species found in freshwater fishes of Mexico, including the species complex of P. lacustri, are not sister species. Phylogenetic analysis based on 28S rDNA sequences of several gorgoderid taxa revealed the close relationship of P. inecoli n. sp. with several species of Phyllodistomum, Gorgodera and Gorgoderina with cystocercous cercariae developing in sphaeriid bivalves. Dot-plot analysis of ITS1 sequences of P. inecoli n. sp. revealed the presence of eight repetitive elements with different length, which together represent almost half the length of ITS1. PMID:24022129

  18. Unique features of pedicellate attachment of the upper jaw teeth in the adult gobiid fish Sicyopterus japonicus (Teleostei, Gobiidiae): morphological and structural characteristics and development.

    PubMed

    Sahara, Noriyuki; Moriyama, Keita; Iida, Midori; Watanabe, Shun

    2013-05-01

    Sicyopterus japonicus (Teleostei, Gobiidae), a hill-stream herbivorous gobiid fish, possesses an unusual oral dentition among teleost fishes on account of its feeding habitat. By using scanning electron microscopy, light microscopy, and transmission electron microscopy, including vital staining with tetracycline, we examined the development of the attachment tissues of the upper jaw teeth in this fish. The functional teeth of S. japonicus had an asymmetrical dentine shaft. The dentine shaft attached to the underlying uniquely shaped pedicel by means of two different attachment mechanisms. At the lingual base, collagen fiber bundles connected the dentine shaft with the pedicel (hinged attachment), whereas the labial base articulated with an oval-shaped projection of the pedicel (articulate attachment). The pedicel bases were firmly ankylosed to the crest of the thin flange of porous spongy bone on the premaxillary bone, which afforded a flange-groove system on the labial surface of the premaxillary bone. Developmentally, the pedicel and thin flange of spongy bone were completely different mineralized attachment tissues. The pedicel had a dual origin, i.e., the dental papilla cells, which differentiated into odontoblasts that constructed the internal surface of the pedicel, and the mesenchymal cells, which differentiated into osteoblasts that formed the outer face of the pedicel. A thin flange of spongy bone was deposited on the superficial resorbed labial side of the premaxillary bone proper, and later rapid bone remodeling proceeded toward the pedicel base. These unique features of pedicellate tooth attachment for the upper jaw teeth in the adult S. japonicus are highly modified teeth for enhancing the ability of individual functional teeth to move closely over irregularities in the rock surfaces during the scraping of algae. PMID:23280699

  19. New insights into the organization and evolution of vertebrate IRBP genes and utility of IRBP gene sequences for the phylogenetic study of the Acanthomorpha (Actinopterygii: Teleostei).

    PubMed

    Detta, Agns; Lecointre, Guillaume

    2008-07-01

    The interphotoreceptor retinoid-binding protein (IRBP) coding gene has been used with success for the large-scale phylogeny of mammals. However, its phylogenetic worth had not been explored in Actinopterygians. We explored the evolution of the structure of the gene and compared the structure predicted from known sequences with that of a basal vertebrate lineage, the sea lamprey Petromyzon marinus. This sequence is described here for the first time. The structure made up of four tandem repeats (or modules) arranged in a single gene, as present in Chondrichthyes (sharks and rays) and tetrapods, is also present in sea lamprey. In teleosts, one to two paralogous copies of IRBP gene have been identified depending on the genomes. When the sequences from all modules for a wide sampling of vertebrates are compared and analyzed, all sequences previously assigned to a particular module appear to be clustered together, suggesting that the divergence among modules is older than the split between lampreys and other vertebrates. Finally, 92 acanthomorph teleosts were sequenced for the partial module 1 of the gene 2 (713 bp) to assess for the first time the use of this marker for the systematic studies of the Teleostei. The partial sequence is slightly more variable than other markers currently used for this group, and the resulting trees from our sequences recover most of the clades described in the recent molecular multi-marker studies of the Acanthomorpha. We recommend the use of partial sequences from the IRBP gene 2 as a marker for phylogenetic inference in teleosts. PMID:18499481

  20. Ultrastructure and development of Nosema podocotyloidis n. sp. (Microsporidia), a hyperparasite of Podocotyloides magnatestis (Trematoda), a parasite of Parapristipoma octolineatum (Teleostei).

    PubMed

    Toguebaye, Bhen Sikina; Quilichini, Yann; Diagne, Papa Mbagnick; Marchand, Bernard

    2014-01-01

    Nosema podocotyloidis n. sp. (Microsporidia, Nosematidae) is described from Podocotyloides magnatestis (Trematoda: Opecoelidae), a parasite of the fish Parapristipoma octolineatum (Teleostei) in the Atlantic Ocean. Electron microscopy reveals that all the stages of the cycle (merogony and sporogony) are diplokaryotic and in direct contact with the cytoplasm of host cells. There is no sporophorous vesicle (pansporoblast). The earliest stages observed are meronts, which have a simple plasmic membrane. Their cytoplasm is granular, rich in ribosomes and contains some sacculi of endoplasmic reticulum. They divide by binary fission into diplokaryotic sporonts. The sporonts have a thick electron-dense wall. Their diplokaryon is slightly less electron-dense than the cytoplasm. The cytoplasm of more advanced sporonts has numerous electron-lucent vesicles. Sporonts with two diplokarya divide by binary fission into diplokaryotic sporoblasts. The older sporoblasts are irregular or elongate and the polar filament is in formation. Their cytoplasm is denser, with ribosomes and lamellae of granular endoplasmic reticulum. The sporoblasts evolve into spores. The mature spores are broadly oval and measure 3.6 (3.1-4.0) × 2.58 (1.8-3.3) μm. Their wall is 100-300 nm thick. The polar tube is isofilar with 11-16 coils, 130-155 nm in diameter and arranged in many layers in the centre of the spore. The polaroplast is divided into two regions: an outer electron-dense cup with granular content and lacking lamellae and an internal region, less electron-dense, composed of irregularly arranged sacs. The posterior vacuole, with an amorphous electron-dense content, is present. The new species is compared with other species of Nosema from trematodes. PMID:25174849

  1. The basement membrane and the sex establishment in the juvenile hermaphroditism during gonadal differentiation of the Gymnocorymbus ternetzi (Teleostei: Characiformes: Characidae).

    PubMed

    Mazzoni, Talita Sarah; Grier, Harry J; Quagio-Grassiotto, Irani

    2015-12-01

    Although there are several studies on morphogenesis in Teleostei, until now there is no research describing the role of the basement membrane in the establishment of the germinal epithelium during gonadal differentiation in Characiformes. In attempt to study these events that result in the formation of ovarian and testicular structures, gonads of Gymnocorymbus ternetzi were prepared for light microscopy. During gonadal development in G. ternetzi, all individuals first developed ovarian tissue. The undifferentiated gonad was formed by somatic cells (SC) and primordial germ cells (PGCs). After successive mitosis, the PGCs became oogonia, which entered into meiosis originating oocytes. An interstitial tissue developed. In half of the individuals, presumptive female, prefollicle cells synthesized a basement membrane around oocyte forming a follicle. Along the ventral region of the ovary, the tissue invaginated to form the ovigerous lamellae, bordered by the germinal epithelium. Stroma developed and the follicle complexes were formed. The gonadal aromatase was detected in interstitial cells in the early steps of the gonadal differentiation in both sexes. In another half of the individuals, presumptive male, there was no synthesis of basement membrane. The interstitium was invaded by numerous granulocytes. Pre-Leydig cells proliferated. Apoptotic oocytes were observed and afterward degenerated. Spermatogonia appeared near the degenerating oocytes and associated to SCs, forming testicular tubules. Germinal epithelium developed and the basement membrane was synthesized. Concomitantly, there was decrease of the gonadal aromatase and increase in the 3β-HSD enzyme expression. Thus, the testis was organized on an ovary previously developed, constituting an indirect gonochoristic differentiation. PMID:26386207

  2. Simultaneous analysis of five molecular markers provides a well-supported phylogenetic hypothesis for the living bony-tongue fishes (Osteoglossomorpha: Teleostei).

    PubMed

    Lavou, Sbastien; Sullivan, John P

    2004-10-01

    Fishes of the Superorder Osteoglossomorpha (the "bonytongues") constitute a morphologically heterogeneous group of basal teleosts, including highly derived subgroups such as African electric fishes, the African butterfly fish, and Old World knifefishes. Lack of consensus among hypotheses of osteoglossomorph relationships advanced during the past 30 years may be due in part to the difficulty of identifying shared derived characters among the morphologically differentiated extant families of this group. In this study, we present a novel phylogenetic hypothesis for this group, based on the analysis of more than 4000 characters from five molecular markers (the mitochondrial cytochrome b, 12S and 16S rRNA genes, and the nuclear genes RAG2 and MLL). Our taxonomic sampling includes one representative of each extant non-mormyrid osteoglossomorph genus, one representative for the monophyletic family Mormyridae, and four outgroup taxa within the basal Teleostei. Maximum parsimony analysis of combined and equally weighted characters from the five molecular markers and Bayesian analysis provide a single, well-supported, hypothesis of osteoglossomorph interrelationships and show the group to be monophyletic. The tree topology is the following: (Hiodon alosoides, (Pantodon buchholzi, (((Osteoglossum bicirrhosum, Scleropages sp.), (Arapaima gigas, Heterotis niloticus)), ((Gymnarchus niloticus, Ivindomyrus opdenboschi), ((Notopterus notopterus, Chitala ornata), (Xenomystus nigri, Papyrocranus afer)))))). We compare our results with previously published phylogenetic hypotheses based on morpho-anatomical data. Additionally, we explore the consequences of the long terminal branch length for the taxon Pantodon buchholzi in our phylogenetic reconstruction and we use the obtained phylogenetic tree to reconstruct the evolutionary history of electroreception in the Notopteroidei. PMID:15324846

  3. Scale surface microstructure and scale size in the tooth-carp genus Aphanius (Teleostei, Cyprinodontidae) from endorheic basins in Southwest Iran.

    PubMed

    Gholami, Zeinab; Teimori, Azad; Esmaeili, Hamid Reza; Schulz-Mirbach, Tanja; Reichenbacher, Bettina

    2013-01-01

    A substantial number of species within the tooth-carp Aphanius Nardo, 1827 (Cyprinodontidae, Teleostei) has been recorded from the endorheic drainage systems of Iran, and several isolated populations in these systems may deserve species status. Descriptions of these species and populations have been based mainly on morphological and molecular data; however, the characters related to the fish scales have not up to now been intensively studied and employed for the identification of the species belonging to this genus. The objective of this study is to test as to whether (i) scale surface morphology, (ii) scale surface microstructure, and (iii) scale size can be used to discriminate species and/or populations and, (iv) to discuss the possible causes of the observed differences. To achieve these objectives, scales of three species of the genus Aphanius from endorheic basins in SW Iran, viz. A. sophiae (nine populations from the Kor River Basin), A. farsicus (four populations from the Maharlu Lake Basin) and A. pluristriatus (a single population from the Mond River Basin) have been studied using SEM images, scale measurements, and uni- and multivariate statistics. It is opined that scale surface morphology and microstructure cannot help in distinguishing the species, but can be employed to discriminate certain populations of A. sophiae (those from Safashahr, Kharameh, Tashk, Gol). In addition, scale size and J-indices, respectively, represent a valuable tool for species separation, which corroborates earlier studies for the use of these indices in taxonomy. Major driving forces of the differentiation within A. sophiae probably include habitat fragmentation resulting from the geological history and local adaptations. Thus the differentiation results from a balance between both genetic and environmental effects. PMID:26131487

  4. Naricolax hoi n. sp. (Cyclopoida: Bomolochidae) from Arius maculatus (Siluriformes: Ariidae) off Taiwan and a redescription of N. chrysophryenus (Roubal, Armitage & Rohde, 1983) from a new host, Seriola lalandi (Perciformes: Carangidae), in Australian waters.

    PubMed

    Hutson, Kate S; Tang, Danny

    2007-10-01

    We propose that Naricolax stocki (Roubal, 1981) (Cyclopoida: Bomolochidae) of Ho & Lin (2005), reported from the spotted catfish Arius maculatus (Thunburg) off Taiwan, represents a new species, N. hoi n. sp. N. hoi can be distinguished from six known congeners by the shape of the rostral area, the maxillary armature and the structural details of legs 3 and 4. N. chrysophryenus (Roubal, Armitage & Rohde, 1983) is redescribed on the basis of recently collected material from wild and farmed yellowtail kingfish Seriola lalandi Valenciennes in southern and eastern Australian waters, providing the first record of Naricolax Ho, Do & Kasahara, 1983 from a carangid host. A key to the species of Naricolax is provided. PMID:17912616

  5. The relationship between fish assemblages and the helminth communities of a prey fish, in a group of small shallow lakes.

    PubMed

    Fernndez, Maria V; Brugni, Norma L; Viozzi, Gustavo P; Semenas, Liliana

    2010-12-01

    Galaxias maculatus (small puyen) is an abundant native fish distributed in lakes and rivers of the Patagonia, and it is the frequent prey of other fishes, fish-eating birds, and mammals. Previous studies have shown that it is parasitized by 33 metazoan species and that the richness and composition of the parasite communities vary between lakes. The aim of the present work was to analyze the relationship between the composition of fish assemblages and the helminth component community structure of G. maculatus . Ten environmentally similar, small, shallow lakes, belonging to the Nahuel Huapi Lake basin, were chosen because of the differences in the native fish assemblages. Parasite community structure in G. maculatus varied according to the fish assemblage of each lake. The presence of the piscivorous fish Percichthys trucha regularly produced variations in the composition and richness at the component and infracommunity levels, as well as the percentage of autogenic parasite species in G. maculatus . PMID:21158611

  6. Post-cyclic transmission in Acanthocephalus tumescens (Acanthocephala: Echinorhynchidae).

    PubMed

    Rauque, Carlos A; Semenas, Liliana G; Viozzi, Gustavo P

    2002-01-01

    The aim of this study was to investigate the post-cyclic transmission of Acanthocephalus tumescens (von Linstow, 1896) from Galaxias maculatus Jenyns to Oncorhynchus mykiss (Walbaum). Wild G. maculatus naturally infected with A. tumescens were fed to cultured rainbow trout, which were sacrificed at the second, third and fourth weeks post infection. Normally attached male and female acanthocephalans were recovered alive from the intestine of rainbow trout. Parasites survive at least four weeks post infection, growing and attaining full sexual maturity. Prevalence and mean intensity generally decreased after infection. A. tumescens is the eighth acanthocephalan species in which post-cyclic transmission has been proven. PMID:12194485

  7. Variable survival across low pH gradients in freshwater fish species.

    PubMed

    Jellyman, P G; Harding, J S

    2014-11-01

    A series of 14 day experiments was conducted on five common New Zealand fish species (redfin bully Gobiomorphus huttoni, inanga Galaxias maculatus, brown trout Salmo trutta, longfin eel Anguilla dieffenbachii and koaro Galaxias brevipinnis) to assess the effect of pH on survival and changes in body mass. No species survived in water of pH <4 although there was 100% survival of all adults at pH 4.5, G. maculatus larvae were also tested and had high mortality at this pH. Results suggest that adults are tolerant of low-pH waters; however, successful remediation of anthropogenically acidified streams will require an understanding of the susceptibility to low pH on different life cycle stages. PMID:25230112

  8. A specimen of Paralycoptera Chang & Chou 1977 (Teleostei: Osteoglossoidei) from Hong Kong (China) with a potential Late Jurassic age that extends the temporal and geographical range of the genus.

    PubMed

    Tse, Tze-Kei; Pittman, Michael; Chang, Mee-Mann

    2015-01-01

    We describe a Mesozoic fish Paralycoptera sp. (Teleostei: Osteoglossoidei), on the basis of a postcranial skeleton collected from the volcaniclastic mudstones of the Lai Chi Chong Formation of Hong Kong, China. The new finding-representing the city's first Mesozoic fish-extends the geographical distribution of Paralycoptera from eastern mainland China into Hong Kong, demonstrating a wider distribution than previously appreciated for this genus. A radiometric age for the Lai Chi Chong Formation of 146.6 0.2 Ma implies a temporal range expansion for Paralycoptera of approximately 40 million years back from the Early Cretaceous (?110 Ma). However, spores found in the Formation suggest an Early Cretaceous age that is consistent with the existing age assignment to Paralycoptera. We argue that the proposed temporal range extension is genuine because it is based on recent high precision radiometric age data, but given the discrepancies with the biostratigraphic ages further investigation is needed to confirm this. This study provides an important step towards revealing Hong Kong's Mesozoic vertebrate fauna and understanding its relationship to well-studied mainland Chinese ones. PMID:25834774

  9. A specimen of Paralycoptera Chang & Chou 1977 (Teleostei: Osteoglossoidei) from Hong Kong (China) with a potential Late Jurassic age that extends the temporal and geographical range of the genus

    PubMed Central

    Tse, Tze-Kei; Chang, Mee-mann

    2015-01-01

    We describe a Mesozoic fish Paralycoptera sp. (Teleostei: Osteoglossoidei), on the basis of a postcranial skeleton collected from the volcaniclastic mudstones of the Lai Chi Chong Formation of Hong Kong, China. The new finding—representing the city’s first Mesozoic fish—extends the geographical distribution of Paralycoptera from eastern mainland China into Hong Kong, demonstrating a wider distribution than previously appreciated for this genus. A radiometric age for the Lai Chi Chong Formation of 146.6 ± 0.2 Ma implies a temporal range expansion for Paralycoptera of approximately 40 million years back from the Early Cretaceous (∼110 Ma). However, spores found in the Formation suggest an Early Cretaceous age that is consistent with the existing age assignment to Paralycoptera. We argue that the proposed temporal range extension is genuine because it is based on recent high precision radiometric age data, but given the discrepancies with the biostratigraphic ages further investigation is needed to confirm this. This study provides an important step towards revealing Hong Kong’s Mesozoic vertebrate fauna and understanding its relationship to well-studied mainland Chinese ones. PMID:25834774

  10. Paracreptotrema profundulusi n. sp. and P. blancoi Choudhury, Pérez-Ponce De León, Brooks, and Daverdin, 2006 (Trematoda: Allocreadiidae) from freshwater fishes of the genus Profundulus (Teleostei: Profundulidae) in southern México.

    PubMed

    Salgado-Maldonado, Guillermo; Caspeta-Mandujano, Juan Manuel; Martínez-Ramírez, Emilio

    2011-08-01

    Paracreptotrema profundulusi n. sp. (Trematoda: Allocreadiidae) is described from the intestine of the freshwater fishes Profundulus punctatus and P. balsanus (Teleostei: Profundulidae) from the Tehuantepec and the Atoyac-Verde River basins, in Oaxaca, México, in the western extreme of Central America. The new species is distinguished from Paracreptotrema blancoi Choudhury, Pérez-Ponce de León, Brooks, and Daverdin, 2006 , to which it is most similar, and from P. mendezi (Sogandares-Bernal, 1955) Choudhury, Pérez-Ponce de León, Brooks, and Daverdin, 2006 , by the caeca extending beyond the testes, vitelline follicles that invade the postesticular area, and uterus with transverse loops located mainly between the testes and the genital pore. Paracreptotrema blancoi was collected from the same host species and also from Profundulus oaxacae. Here, we provide data that show its broad distribution in several river basins of Neotropical southern México, including the Papagayo River basin, Guerrero, México, and the Atoyac-Verde and Tehuantepec river basins, and other rivers in Oaxaca, México. Freshwater fishes of the Profundulidae are endemic to Central America and host a helminth fauna that includes at least 4 species found only in these hosts. PMID:21506847

  11. Detection of dwarf gourami iridovirus (Infectious spleen and kidney necrosis virus) in populations of ornamental fish prior to and after importation into Australia, with the first evidence of infection in domestically farmed Platy (Xiphophorus maculatus).

    PubMed

    Rimmer, Anneke E; Becker, Joy A; Tweedie, Alison; Lintermans, Mark; Landos, Matthew; Stephens, Fran; Whittington, Richard J

    2015-11-01

    The movement of ornamental fish through international trade is a major factor for the transboundary spread of pathogens. In Australia, ornamental fish which may carry dwarf gourami iridovirus (DGIV), a strain of Infectious spleen and kidney necrosis virus (ISKNV), have been identified as a biosecurity risk despite relatively stringent import quarantine measures being applied. In order to gain knowledge of the potential for DGIV to enter Australia, imported ornamental fish were sampled prior to entering quarantine, during quarantine, and post quarantine from wholesalers and aquatic retail outlets in Australia. Samples were tested by quantitative polymerase chain reaction (qPCR) for the presence of megalocytivirus. Farmed and wild ornamental fish were also tested. Megalocytivirus was detected in ten of fourteen species or varieties of ornamental fish. Out of the 2086 imported gourami tested prior to entering quarantine, megalocytivirus was detected in 18.7% of fish and out of the 51 moribund/dead ornamental fish tested during the quarantine period, 68.6% were positive for megalocytivirus. Of fish from Australian wholesalers and aquatic retail outlets 14.5% and 21.9%, respectively, were positive. Out of 365 farmed ornamental fish, ISKNV-like megalocytivirus was detected in 1.1%; these were Platy (Xiphophorus maculatus). Megalocytivirus was not detected in free-living breeding populations of Blue gourami (Trichopodus trichopterus) caught in Queensland. This study showed that imported ornamental fish are vectors for DGIV and it was used to support an import risk analysis completed by the Australian Department of Agriculture. Subsequently, the national biosecurity policy was revised and from 1 March 2016, a health certification is required for susceptible families of fish to be free of this virus prior to importation. PMID:26452601

  12. Estructuras circumnucleares en la galaxia Seyfert interactuante NGC 1241

    NASA Astrophysics Data System (ADS)

    Daz, R. J.; Carranza, G.; Dottori, H.

    We have studied the rotation curve and morphology of the central 10 kiloparsecs (~40'') of NGC 1241 obtaining 50 radial velocity measurements in three different position angles. These observations indicate a large velocity gradient of 70 km/sec/('') in the central 5''. The fitting of different density distribution laws to the derived rotation curve indicates a mass of ~ 9 E9 Msolar in the inner kpc. HST-NICMOS images show the presence of a circumnuclear star formation ring at radius ~ 2.8'' (720 pc). This ring is more defined than most of the known cases and harbours a mini-bar and nuclear spiral arms with a sense of rotation opposite than the main spiral arms. This morphological evidence suggest the presence of a dynamically decoupled system inside the circumnuclear ring. As in other cases studied by us, the ring seems to be inside an Inner Lindblad Resonance and the Lindblad curve ?-?/2 for this object begins to drop for Rmax = 400 pc (~1.5''), but the limited spatial resolution does not allow us to find out a definitive evidence for the existence of a second ILR inside at inner radii. Up to date there is no published morphological or kinematical evidence for the presence of a second ILR at such small radii, a necessary ingredient for the presence of circumnuclear ring of star formation, considering the results of recent hydrodynamic simulations. We have proposed the observation of NGC 1241 with better instruments in order to extend the rotation curve to the central 2'', unveil the presence of a second inner resonance, study in detail the structural properties of the nuclear counterrotating arms and establish accurate models of mass distribution in galaxies with circumnuclear rings. This program has been awarded with Band 1 observing time at the Gemini North Telescope Quick Start Stage (Brasil and Argentina).

  13. Anlisis de la formacin de galaxias en grupos

    NASA Astrophysics Data System (ADS)

    Prez, M. J.; Tissera, P.; Garca Lambas, D.

    The actual cosmological paradigm postulates that structure formation occurs in a hierarchical way. In such scenarios, interactions among galaxies are frequent and play an important role in determining their properties, and particularly, in the regulation of star formation. Observations show that interactions and collisions can increase the star formation rate (Larson & Tinsley 1978; Donzelli & Pastoriza 1997; Barton et al 1998). In particular, recent observational results (Garca Lambas, Tissera, Alonso & Coldwell, 2003) show that star formation in galaxy pairs is significantly enhanced over that of isolated galaxies with the same redshift distribution. Theoretical interpretation of these observational results could be associated to the dynamical stability of galactic systems. Numerical simulations show that disc galaxies without bulges or with small ones, tend to develop instabilities induced by tidal interactions which produce gas inflows and trigger star formation (Mihos & Hernquist 1996; Domnguez-Tenreiro, Tissera & Siz 1998). Although simulations and observations show the effects of galaxy interactions on the star formation, intrinsic properties of galaxies in pairs must play a crucial role due to high observed fraction of galaxies pairs with low star formation rate (Garca Lambas et al 2003). In order to see if these observational results are reproduced in hierarhical clustering scenarios, we study the star formation of galaxy pairs, as well as any possible effects provoked by interactions on other astrophysical properties, such the chemical ones. For this purpose, we use hydrodynamical simulations consistent with a CDM model: ?=1, ?=0 and H0=50 km s-1 Mpc-1, which include star formation and chemical evolution (Mosconi et al 2001). We analyzed three different realizations of the power spectrum in the redshift range of the 2dFGRS catalog (Garca Lambas et al. 2003). Identified structures were classified as isolated galaxies and galaxies in closed pairs, and then grouped according to the environment. Firstly, the classification was carried out by using the 3D velocity and spatial separations. In agreement with the observational results, we found that closed encounters with a relative 3D distances r<30 kpc, show an enhancement of star formation rate with respect to the mean field value (bar{b}=3.04) calculated considering galaxies with r > 100 kpc. Preliminary results show the media abundance of (O/H) of the stellar populations in closed pairs is systematically higher than that value for field galaxies, suggesting a tendency with the relative 3D distances, which can be associated to a major production of SNII originated by the enhancement of star formation in closed pair galaxies. The interstellar medium shows the same trend but with lower mean abundance values suggesting an accretion of low metallicity gas. Fe is produced mainly by SNI, with a delay of 0.1 Gyr; therefore, it is not coupled to present star formation activity but to the history of star formation. Our results suggest a certain trend for Fe to be higher at smaller relative 3D distances. The higher Fe abundances indicate that closer pairs might have a major old stellar population. Future works involved the performance of a mock pair catalog by projecting the 3D-simulated pair galaxies and the study of the properties of projected pairs and the effects of interlopers on the conclusions drawn from them (Prez et al., in preparation).

  14. El origen de las galaxias esferoidales en simulaciones Cosmolgicas

    NASA Astrophysics Data System (ADS)

    Algorry, D. G.; Abadi, M. G.

    We use the GIMIC cosmological hydrodynamical simulations to perform a study of the properties of spheroidal galaxies formed without merger events. We select a sample of galaxies with stellar mass greater than 10 M and we classified them according to the degree of rotation support through the ratio of the rotational kinetic energy respect to the total at redshift z=0. Taken only those with ; we focus on those with accreted mass fraction less than 20 to ensure that they are merger free. We found that these spheroidal galaxies have stellar mass M M and have an important barred component. Interestingly; we found that in many cases the simulated galaxies present two external rings around the bar being both coplanar and counter-rotating to each other. FULL TEXT IN SPANISH

  15. Componentes contra-rotantes en simulaciones de galaxias disco

    NASA Astrophysics Data System (ADS)

    Algorry, D. G.; Abadi, M. G.

    In this work we present a dynamical analysis of two simulated disk galaxies, having both counter-rotating stellar components. The dynamical properties of the stellar particles of these galaxies, such as velocity, energy and circu- larity of the orbits, show that there is an internal component which rotates in opposite direction to the galactic disk. This study allows us to com- pare these simulated galaxies to those found in the last few years having counter-rotating components. FULL TEXT IN SPANISH

  16. Efectos de extincin en curvas de rotacin de galaxias espirales

    NASA Astrophysics Data System (ADS)

    Valotto, C.; Giovanelli, R.

    Observations show that the slope of the inner part of the H?/[NII] rotation curves of disk galaxies is depressed by extinction: at fixed luminosity, the observed slope is in fact seen to depend on the disk inclination to the line of sight. Using a simple extinction model, we are able to reproduce well the observed trends. The model assumes an exponential distribution, both in the radial and z directions, identical for star-forming regions and dust. Fits to the data are optimized by varying the scale height and scale length of absorbers, as well as the disk's central optical depth ?o, as seen face-on. The observations indicate that disk central opacity increases with total luminosity. Model fits for the most luminous galaxies (brighter than M-5 log h=-21.4 in the I band) yield ?o ? 3.5+4.0-2.0, near ?=0.66 ?m. The large uncertainty on the inferred value of ?o is due to the poorly known characteristics of the distribution of absorbers in the disk, as well as to the likelihood of strong departures from an exponential radial distribution near the galaxy centers.

  17. Grupos de galaxias con corrimiento al rojo intermedio

    NASA Astrophysics Data System (ADS)

    Salerno, J. M.; Muriel, H.; Alonso, M. V.; Valotto, C.

    2015-08-01

    We present the construction of a catalog of groups of galaxies obtained through a sample of 677 spectra obtained with VIMOS-MOS spectrograph at the VLT. The sample has a redshift range and includes randomly selected galaxies brighter than in the R band. Groups of galaxies are identified using the algorithm Friends-of-friends (FOF). Linking lengths are taken as and . We also performed a visual reconstruction of the FOF groups. Finally, the basic properties of groups were estimated: velocity dispersion, virial mass and radius.

  18. Espectroscopa infrarroja de la galaxia Seyfert NGC6300

    NASA Astrophysics Data System (ADS)

    Gaspar, G.; DAmbra, A.; Daz, R. J.; Gunthardt, G.; Gmez, P.

    2015-08-01

    Here we present a spectroscopic study in the near infrared band of the active galaxy NGC 6300, with spectra obtained with the spectrograph Flamingos 2 of the telescope Gemini South. The spectra were taken in the range 1 to 2.4 mm, with a mean spatial resolution of 0.6'', in this work we present preliminary results for a single band, . This global study is based in the analysis of the relative contributions in the emission of the Seyfert nuclei and the circunnuclear star formation to discuss later the role of the AGN in the scenarios of dynamical evolution of galaxies. We present the detection of a broad component in the Pa emission line, an unexpected feature in this galaxy so far classified as a 2 type.

  19. NGC 1566: una galaxia espiral ``grand design'' con ncleo Seyfert

    NASA Astrophysics Data System (ADS)

    Agero, E.; Daz, R. J.; Bajaja, E.

    The galaxy NGC 1566 was studied kinematical and spectroscopically on the basis of spectra taken at CASLEO along six different position angles through the nucleus. The obtained information was integrated with data at radio frequencies. It was found that there are emission regions in the arms whose H? radiation is higher or of the same order than in the nucleus, and that the nucleus was in a low level of activity during observations. The star bursts in the circumnuclear ring seem to be younger than in the arms, and there are very good correlations between the distributions of the flux densities of H?, the continuum at 843 MHz and the emission of the CO line at 115 GHz. This correlations suggests that the H? emission would be related to the thermal component of the continuum radiation, and the molecular gas is present in the nucleus and through the disk of the galaxy. The rotation curve and the mass were determined, and non-circular motions were detected.

  20. Effect of ramp length and slope on the efficacy of a baffled fish pass.

    PubMed

    Baker, C F

    2014-02-01

    This study evaluated the effect of ramp length and slope on fish passage over baffled ramps with 15° and 30° gradients. Three fish species indigenous to New Zealand were tested: the redfin bully Gobiomorphus huttoni, the common bully Gobiomorphus cotidianus and the inanga Galaxias maculatus with ramp lengths of 3, 4·5 and 6 m. As slope and ramp length increased, passage success rate decreased for G. maculatus and G. cotidianus. At a slope of 15°, both G. maculatus and G. cotidianus could pass all ramp lengths tested with the highest success rate on the 3 m ramp. As the gradient increased to 30°, G. maculatus could only pass the 3 m ramp, and G. cotidianus were incapable of passing any ramp. Gobiomorphus huttoni were the only test species capable of climbing the wetted margin of the ramps. Increasing ramp slope significantly reduced passage success for G. huttoni, but ramp length, up to the maximum used in this study, had no significant influence on successful passage. PMID:24417428

  1. Extensive genetic divergence among Diptychus maculatus populations in northwest China

    NASA Astrophysics Data System (ADS)

    Meng, Wei; Yang, Tianyan; Hai, Sa; Ma, Yanwu; Cai, Lingang; Ma, Xufa; Gao, Tianxiang; Guo, Yan

    2015-05-01

    D. maculates is a kind of specialized Schizothoracinae fish has been locally listed as a protected animal in Xinjiang Province, China. Ili River located in north of Tianshan Mountain and Tarim River located in north of Qinghai-Tibetan Plateau were two main distribution areas of this fish. To investigate the genetic diversity and genetic structure of D. maculates, four populations from Tarim River system and two populations from Ili River system were collected in this study. A 570-bp sequence of the control region was obtained for 105 specimens. Twenty-four haplotypes were detected from six populations, only Kunes River population and Kashi River population shared haplotypes with each other. For all the populations examined, the haplotype diversity ( h) was 0.904 8±0.012 6, nucleotide diversity (π) was 0.027 9±0.013 9, and the average number of pairwise nucleotide differences ( k) was 15.878 3±7.139 1. The analysis of molecular variance (AMOVA) showed that 86.31% of the total genetic variation was apportioned among populations, and the variation within sampled populations was 13.69%. Genetic differences among sampled populations were highly significant. F st statistical test indicated that all populations were significantly divergent from each other ( P<0.01). The largest F st value was between Yurungkash River population and Muzat River population, while the smallest F st value was between Kunes River population and Kashi River population. NJ phylogenetic tree of D-loop haplotypes revealed two main clades. The neutrality test and mismatch distribution analysis suggested that the fish had went through a recent population expansion. The uplift of Tianshan Mountain and movement of Qinghai-Tibetan Plateau might contribute to the wide genetic divergence of D. maculates in northwest China.

  2. Estructura espacial de las rbitas caticas en un modelo autoconsistente de galaxia elptica

    NASA Astrophysics Data System (ADS)

    Muzzio, J. C.

    Hemos logrado construir modelos autoconsistentes de sistemas estelares utilizando una aproximacin cuadrupolar para el potencial. Esto nos permite determinar rbitas y exponentes de Lyapunov de objetos que tienen posiciones y velocidades equivalentes a las que se obtienen de la funcn de distribucin del sistema. La distribucin espacial de las rbitas caticas exhibe considerable estructura y, lo que es ms importante an, los valores de los exponentes de Lyapunov calculados sobre intervalos finitos de tiempo, muestran una fuerte correlacin con el comportamiento de la rbita en esos mismos intervalos, por lo que permiten reconocer distintos subsistemas con diferentes distribuciones espaciales.

  3. Origen y evolucin de la relacin de Tully-Fisher en galaxias simuladas

    NASA Astrophysics Data System (ADS)

    Ferrero, I.; Abadi, M. G.; Algorry, D. G.

    2015-08-01

    Using the hydrodynamic cosmological simulations of galaxy formation Gimic (Galaxies Intergalactic Medium-Interaction Calculation) we study the origin and the evolution of the Tully-Fisher relation in comparison with same observational results for different redshifts ranging from z = 0 to z = 2. Preliminary results indicate the possible existence of a conspiracy between the amounts of dark matter and baryons (stars and gas) in the central parts of galaxies which is fundamental to establishing this correlation.

  4. La abundancia de galaxias y halos de materia oscura en el universo CDM

    NASA Astrophysics Data System (ADS)

    Abadi, M. G.; Bentez-Llambay, A.; Ferrero, I.

    A long-standing puzzle of CDM cosmological model concerns to the different shape of the galaxy stellar mass function and the halo mass function on dwarf galaxy scales. Dwarf galaxies are much less numerous than halos massive enough to host them; suggesting a complex non-linear relation between the mass of a galaxy and the mass of its surrounding halo. Usually; this is reconciled by appealing to baryonic processes that can reduce the efficiency of galaxy formation in low-mass halos. Recent work applying the abundance matching technique require that virtually no dwarf galaxies form in halos with virial mass below . We use rotation curves of dwarf galaxies compiled from the literature to explore whether their total enclosed mass is consistent with these constraints. Almost one-half of the dwarfs in our sample are at odds with this restriction; they are in halos with masses substantially below . Using a cosmological simulation of the formation of the Local Group of galaxies we found that ram-pressure stripping against the cosmic web removes baryons from low-mass halos without appealing to feedback or reionization. This mechanism may help to explain the scarcity of dwarf galaxies compared with the numerous low-mass halos expected in CDM and the large diversity of star formation histories and morphologies characteristic of faint galaxies. FULL TEXT IN SPANISH

  5. Cinematica del gas ionizado y perfiles de luminosidad de las Galaxias Porotos Verdes

    NASA Astrophysics Data System (ADS)

    Diaz, R. J.; Aguero, M.; Schirmer, M.; Holheim, K.; Levenson, N.; Winge, C.

    We present preliminary spectroscopic results of a sample of green bean galaxies (GBG); known to show ultra-luminous; galaxy-wide; narrow-line regions. We analyze Gemini GMOS-S;N spectra of a sample of 12 GBG in order to obtain emission line ratios; gas kinematics and luminosity profiles in some continuous bands. We report here new results that confirm that the 5008 emission extends from 5 to 17 kpc; in all cases scales similar or larger than the stellar continuums at the spectra. In the extreme case of J145533.6+044643 the emission reaches a diameter of 17.51.6kpc. We find that the continuum half light radii extend from 3 to 7 kpc; the largest scale radius at shortest wavelengths; which is consistent with the scale lengths of large spiral galaxies or merging systems. Another new result is that the spatial variation of the continuum color profiles indicate the presence of extinction and possibly star formation. FULL TEXT IN SPANISH

  6. Una nueva galaxia IR con nucleo compuesto: Seyfert 1.5 y estallido de formacion estelar

    NASA Astrophysics Data System (ADS)

    Lipari, S. L.; Merlo, D. C.; Moyano, M. M.

    Optical aperture spectroscopy and CCD broad- and narrow-band images are presented for the barred Seyfert 1 galaxy: IRAS 22117-3903. IRAS data are also used to analyse this object. The CTIO broad band CCD imaging show interesting morphological features: a compact nucleus with a prominent bar; two bright spiral arms; and a partial/segmented inner ring. The narrow-band imaging show that the nuclear H+[NII] emission is concentrate mainly in the nucleus. We find optical spectral features characteristic of a Seyfert 1.5 nucleus; i.e.; showing hydrogen emission lines with broad and narrow components. We detected high excitation emission lines ([CaV]+[FeXIV]; [FeVII]). We study the stellar population in the nuclear region. We find that the stellar population that represent quite well the nuclear stellar population is an average of spiral galaxies dominated by the old population plus a contribution of young stars. Physical conditions are derived for the narrow emission line region; and we detected very high electron temperature (T=4400045000 K); untypical for the ordinary AGNs and probably associated to shocks in a starburst component. Finally; at the optical and IR wavelength; we find properties typical of an nucleus with compound nature; in good agreement with the AGN/QSOs evolutionary model of Lpari ; Terlevich (2006; ; 368; 1001). FULL TEXT IN SPANISH

  7. Dinámica global en galaxias elípticas

    NASA Astrophysics Data System (ADS)

    Pérez, M. J.; Cincotta, P. M.; Giordano, C. M.

    Con el propósito de determinar propiedades dinámicas globales en sistemas triaxiales no integrables, utilizamos una nueva herramienta conocida como ``Mean Exponential Growth factor of Nearby Orbits'' (MEGNO), introducida por Cincotta y Simó (2000). Esta técnica no sólo resulta eficiente para investigar ambas componentes del espacio fase, regular y caótica, sino que también, provee una medida de la hiperbolicidad en el dominio caótico que coincide con la dada por el Lyapunov Characteristic Number (LCN). Previamente este método ha sido aplicado al estudio de modelos simples, y últimamente en el campo de la Mecánica Celeste, al estudio de sistemas planetarios extrasolares. En esta presentación, ilustraremos algunas de las propiedades más importantes del MEGNO, aplic& acute;andolo al potencial tridimensional de Stäckel perturbado.

  8. Fine structural analysis of a teleost exocrine pancreas cellular components - a freeze-fracture and transmission electron microscopic study.

    PubMed

    Stipp, A C; Ferri, S; Sesso, A

    1980-01-01

    The normal exocrine pancreas of Pimelodus maculatus (Teleostei) has been studied by freeze-fracture and conventional transmission electron microscopy. 4 cellular types in the acini are observed: the acinar cells, the argentaffin cells, the intermediate cells and the centroacinar cells. The most proeminent cytoplasmic feature of the acinar cells is that the well developed rough endoplasmic reticulum, which appear predominantly under the vesicular form. The argentaffin cells are found lodged between the acinar cells and duct cells, in the connective tissue they are isolated principally that surrounds the ducts. The typical granules are the cytoplasmic component wich characterize the argentaffin cells. The indermediate cells are characterized by the presence of two distinct granule types: one resembling that found in the endocrine cells and the other resembling the granules of the acinar cells. The centroacinar cells is similar that found in other species. PMID:7396226

  9. Source and trophic transfer of mercury in plankton from an ultraoligotrophic lacustrine system (Lake Nahuel Huapi, North Patagonia).

    PubMed

    Rizzo, Andrea; Arcagni, Marina; Campbell, Linda; Koron, Neža; Pavlin, Majda; Arribére, María A; Horvat, Milena; Guevara, Sergio Ribeiro

    2014-09-01

    The incorporation and trophic transfer of total and methyl mercury (THg, MeHg) were examined in three size classes of plankton (10-53, 53-200, and >200 μm size range) and a small planktivorous fish, Galaxias maculatus, from the large multi-branched Lake Nahuel Huapi (North Patagonia, Argentina). Three sites representing a large range of lake benthic-pelagic structures (based on depth and shoreline characteristics) and precipitation regimes were sampled. Nitrogen and carbon stable isotopes (δ(15)N, δ(13)C) were analyzed to assess Hg trophodynamics. Selenium concentrations were determined together with THg in order to consider its potential effect on Hg trophodynamics. High THg concentrations (0.1-255 µg g(-1) dry weight (DW)) were measured in plankton, largely in inorganic form (MeHg: 3-29 ng g(-1) DW, 0.02-7% of THg, in the two larger size classes). A trend of increasing THg concentrations, varying in two to three orders of magnitude, with decreasing plankton size was associated with precipitation measured prior to each sampling event. Passive adsorption of dissolved Hg(2+) from wet deposition and runoff is considered to be the principal Hg uptake mechanism at the base of the pelagic food web. Despite the initially high THg uptake in the smaller plankton classes, the transfer to G. maculatus, and consequently to the entire food web, is likely limited due to low proportion of MeHg to THg in plankton. Furthermore, evidence of G. maculatus with benthic feeding habits having higher impact on MeHg trophic transfer compared to the same species with more pelagic (e.g., zooplankton) feeding habits, was observed. Although there is a high THg uptake in plankton, limited amounts are incorporated in the entire food web from the pelagic compartment. PMID:24844168

  10. The complete mitochondrial genome of Rhinogobio ventralis (Teleostei, Cyprinidae, Gobioninae).

    PubMed

    Liu, Ya; Li, Qiang; Gong, Quan; Li, Hua; Du, Jun

    2015-08-01

    Rhinogobio ventralis, a small-sized economic fish living in the bottom of the fast-flowing water, has a limited geographical distribution in the upper reaches of Yangtze River in China. The complete mito-genome of R. ventralis is 16,607?bp in length, containing 37 genes of 13 protein-coding genes, 22 tRNA genes, two rRNA genes and a control region (D-loop). The gene order and composition of R. ventralis is similar to that of most other fishes, and its nucleotide composition is 31.10% A, 26.64% T, 26.28% C and 15.98% G, with a slight AT bias of 57.74%. It is first report of the complete mitochondrial genome in the bottom dwelling Rhinogobio species. PMID:24090006

  11. The complete mitochondrial genome of Rhinogobio cylindricus (Teleostei, Cyprinidae).

    PubMed

    Liu, Ya; Li, Qiang; Zhou, Jian; Lai, Jiansheng; Zhao, Gang

    2015-12-01

    Rhinogobio cylindricus, a bottom-dwelling fish, is the one of two endemic species of genus Rhinogobio in the upper Yangtze River. Its phylogenetic status remains controversial. In this study, we sequenced the complete mito-genome of R. cylindricus. The genome is 16,610?bp in length, containing 22 tRNA genes, 13 protein-coding genes, 2 rRNA genes and a control region (D-loop). The nucleotide composition is 31.03% A, 26.91% C, 16.20% G and 25.86% T, with a slight AT bias of 56.89%, which is similar to that of most other fishes. PMID:24409921

  12. The complete mitochondrial genome of the Plectorhinchus cinctus (Teleostei, Haemulidae).

    PubMed

    Liu, Li; Yang, Huirong; Zhao, Huihong; Sun, Jijia; Han, Xingpeng; Zhu, Shaoxuan; Li, Guifeng

    2016-03-01

    We present the complete mitochondrial genome of the Plectorhinchus cinctus in this study. The mitochondrial genome is 16,523 bp in length and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region. The nucleotide compositions of the light strand are 31.30% of C, 27.66% of A, 24.54% of T, and 16.50% of G. With the exception of ND6 and eight tRNA genes, all other mitochondrial genes are encoded on the heavy strand. All the protein-coding genes begin with an ATG initiation codon except for COX1 with GTG. Five types of termination codons revealed are TAA (ND1, ND2, ATP8, ND4L, ND5), T (COXП, ND3, ND4, CYTB), TA (ATP6, COXШ), AGG (COXІ) and TAG (ND6). PMID:24865922

  13. Complete mitochondrial genome of Florida pompano Trachinotus carolinus (Teleostei, Carangidae).

    PubMed

    Zhang, Dianchang; Wang, Long; Guo, Huayang; Ma, Zhenhua; Zhang, Nan; Lin, Junda; Jiang, Shigui

    2016-01-01

    The complete mitochondrial genome sequence of Florida pompano Trachinotus carolinus was determined by the overlapped polymerase chain reaction. The complete mitochondrial DNA sequence is 16,544 bp in length. It consists of 13 protein-coding genes, 22 transfer RNA genes, two rRNA genes and two non-coding regions. Overall base composition of its mitochondrial genome is estimated to be 28.68% for A, 16.27% for G, 26.00% for T, 29.06% for C, respectively, with a high A+T content (54.68%). The control region contains three conserved sequence blocks, a termination-associated sequence and a TATA box. The sequence data of T. carolinus can provide useful information for the studies on population structure, molecular systematic, stock evaluation and conservation genetics. It is also helpful to develop the rational management strategies for T. carolinus resource. PMID:24730608

  14. The complete mitochondrial genome of Liobagrus marginatus (Teleostei, Siluriformes: Amblycipitidae).

    PubMed

    Li, Qiang; Du, Jun; Liu, Ya; Zhou, Jian; Ke, Hongyu; Liu, Chao; Liu, Guangxun

    2014-04-01

    The Liobagrus marginatus is an economic fish which distribute in the upstream of Yangtze river and its distributary. For its taste fresh, environmental pollution and overfishing, its population declined drastically and body miniaturization in recent decades, so it is essential to protect its resource. In this study, the complete mitochondrial genome sequence of Liobagrus marginatus was sequenced, which contains 22 tRNA genes, 13 protein-coding genes, 2 rRNA genes, and a non-coding control region with the total length of 16,497 bp. The gene arrangement and composition are similar to most of other fish. Most of the genes are encoded on heavy-strand, except for eight tRNA and ND6 genes. Just like most other vertebrates, the bias of G and C has been found in statistics results of different genes/regions. The complete mitochondrial genome sequence of Liobagrus marginatus would contribute to better understand population genetics, evolution of this lineage, and will help administrative departments to make rules and laws to protect it. PMID:23795826

  15. Eviota piperata, a new gobiid species from Palau (Teleostei: Gobiidae).

    PubMed

    Greenfield, David W; Winterbottom, Richard

    2014-01-01

    A new species of dwarfgoby, Eviota piperata is described from Palau. It belongs to the cephalic sensory-pore system Group II (lacking only the IT pore); has a dorsal/anal-fin formula of 8/8; has some pectoral-fin rays branched; no dark spot over the ural centrum; the male genital papilla is not fimbriate; and the cheek and body are heavily peppered with chromatophores. PMID:24869823

  16. Evolutionary history of anglerfishes (Teleostei: Lophiiformes): a mitogenomic perspective

    PubMed Central

    2010-01-01

    Background The teleost order Lophiiformes, commonly known as the anglerfishes, contains a diverse array of marine fishes, ranging from benthic shallow-water dwellers to highly modified deep-sea midwater species. They comprise 321 living species placed in 68 genera, 18 families and 5 suborders, but approximately half of the species diversity is occupied by deep-sea ceratioids distributed among 11 families. The evolutionary origins of such remarkable habitat and species diversity, however, remain elusive because of the lack of fresh material for a majority of the deep-sea ceratioids and incompleteness of the fossil record across all of the Lophiiformes. To obtain a comprehensive picture of the phylogeny and evolutionary history of the anglerfishes, we assembled whole mitochondrial genome (mitogenome) sequences from 39 lophiiforms (33 newly determined during this study) representing all five suborders and 17 of the 18 families. Sequences of 77 higher teleosts including the 39 lophiiform sequences were unambiguously aligned and subjected to phylogenetic analysis and divergence time estimation. Results Partitioned maximum likelihood analysis confidently recovered monophyly for all of the higher taxa (including the order itself) with the exception of the Thaumatichthyidae (Lasiognathus was deeply nested within the Oneirodidae). The mitogenomic trees strongly support the most basal and an apical position of the Lophioidei and a clade comprising Chaunacoidei + Ceratioidei, respectively, although alternative phylogenetic positions of the remaining two suborders (Antennarioidei and Ogcocephaloidei) with respect to the above two lineages are statistically indistinguishable. While morphology-based intra-subordinal relationships for relatively shallow, benthic dwellers (Lophioidei, Antennarioidei, Ogcocephaloidei, Chaunacoidei) are either congruent with or statistically indistinguishable from the present mitogenomic tree, those of the principally deep-sea midwater dwellers (Ceratioidei) cannot be reconciled with the molecular phylogeny. A relaxed molecular-clock Bayesian analysis of the divergence times suggests that all of the subordinal diversifications have occurred during a relatively short time period between 100 and 130 Myr ago (early to mid Cretaceous). Conclusions The mitogenomic analyses revealed previously unappreciated phylogenetic relationships among the lophiiform suborders and ceratioid familes. Although the latter relationships cannot be reconciled with the earlier hypotheses based on morphology, we found that simple exclusion of the reductive or simplified characters can alleviate some of the conflict. The acquisition of novel features, such as male dwarfism, bioluminescent lures, and unique reproductive modes allowed the deep-sea ceratioids to diversify rapidly in a largely unexploited, food-poor bathypelagic zone (200-2000 m depth) relative to the other lophiiforms occurring in shallow coastal areas. PMID:20178642

  17. The complete mitochondrial gemone of Phoxinus lagowskii (Teleostei, Cypriniformes: Cyprinidae).

    PubMed

    Sun, Qinliang; Wang, Dengqiang; Wei, Qiwei

    2016-03-01

    In this paper, we determined the whole mitochondrial DNA (mtDNA) sequence of Phoxinus lagowskii, a small freshwater fish that is distributed in rivers of north China, Russia and North Korea. The entire sequence of P. lagowskii mitochondrial genome is 16,699 bp in size, consisting of 13 protein-coding genes, 2 ribosomal RNA genes (12S rRNA and 16S rRNA), 22 transfer RNA genes (tRNA) and 1 putative control region. Most of the genes are encoded on the heavy strand except ND6 and eight tRNA genes (Gln, Ala, Asn, Cys, Try, Ser, Glu and Pro) encoded on the light strand. PMID:24865913

  18. The complete mitochondrial genome of Alburnus tarichi (Teleostei, Cyprinidae).

    PubMed

    Kubanç, Nerdin; Eldem, Vahap; Kubanç, Cüneyt

    2016-03-01

    Alburnus tarichi is the only vertebrate species that can survive in Lake Van, the largest soda lake on Earth, which is characterized by extremely high pH and salinity. The circular mitogenomes of A. tarichi was 16,602 base pairs in size, containing 13 protein-coding genes (PCGs), 2 rRNA genes, 22 tRNA genes, and 2 major non-coding control regions (D-Loop and OL). Congurence was observed between the Alburnus mtDNAs in terms of genome organization, base composition, gene arrangement, and tRNA structure. Mitogenome sequences may be useful for conservation efforts of this endangered species. PMID:25090382

  19. Phylogenetic footprints of an Antarctic radiation: the Trematominae (Notothenioidei, Teleostei).

    PubMed

    Lautrdou, A-C; Hinsinger, D D; Gallut, C; Cheng, C-H C; Berkani, M; Ozouf-Costaz, C; Cruaud, C; Lecointre, G; Dettai, A

    2012-10-01

    The teleost suborder Notothenioidei is restricted to the Southern Ocean and has been described as a species flock spanning the whole of it. Within the suborder, the subfamily Trematominae is important for coastal Antarctic ecosystems. The eleven Trematomus species occupy a large range of ecological niches. The genus is monophyletic if the genus Pagothenia (two additional species) and Cryothenia amphitreta, also nested within it, are included. Although the Trematominae have received much interest, the relationships among these fourteen species are still unclear. Several recent studies have tried to resolve these interrelationships; however no complete and clear picture has emerged, probably because of the use of a low number of insufficiently variable markers. The only common results places T. scotti as the sister-group of the rest of the subfamily and T. loennbergi close to T. lepidorhinus. We use here more variable markers. Four nuclear markers, two of which are new, and a mitochondrial marker for the biggest trematomine sampling ever gathered (14 species, 78 specimens). We found that several nuclear haplotypes are shared by several species (mostly in very closely related species). The haplotype patterns coupled with the cytogenetics of the subfamily suggest that a phenomenon of incomplete lineage sorting (ILS) is likely to be at play. Using a calibration linked to fossil evidence, we evaluate the relative ages of each clade within the Trematominae to assess the proximity of the speciation events to one another. The main trematomine diversification was recent and sudden. PMID:22683562

  20. A new species of Ptychochromis from southeastern Madagascar (Teleostei: Cichlidae).

    PubMed

    Martinez, Christopher M; Arroyave, Jairo; Sparks, John S

    2015-01-01

    We describe a new species in the endemic Malagasy cichlid genus Ptychochromis. Ptychochromis mainty, new species, is known from four individuals, all collected in the Fort Dauphin region of southeastern Madagascar, and shares a palatine morphology (eastern-type palatine) with other eastern congeners. Ptychochromis mainty is distinguished from all congeners by a nearly uniform dark brown to black pigmentation pattern in preservation and by the presence of a relatively continuous and expansive black longitudinal midlateral blotch in life, extending from the posterior margin of the opercle to the caudal peduncle. The new species is further distinguished from other eastern Ptychochromis species by having minimal or no overlap of the first supraneural with the dorsoposterior region of the supraoccipital crest (vs. marked overlap). We present a molecular-based phylogeny for all available Ptychochromis species, which supports the hypothesis that P. mainty is a distinct taxon. The new species is recovered as the sister taxon to P. grandidieri within a clade comprising species with an eastern-type palatine morphology. We present a geometric morphometric analysis that provides additional evidence to distinguish P. mainty from congeners. PMID:26624703

  1. The adrenal chromaffin cells of Salmo gairdneri Richardson (Teleostei, Salmonidae).

    PubMed Central

    Mastrolia, L; Gallo, V P; La Marca, A

    1984-01-01

    The chromaffin cells of the adrenal homologue of Salmo gairdneri R. have been studied by light and electron microscopy. The chromaffin tissue was localised in the head kidney adjacent to the wall of the proximal part of the cardinal veins and their main branches. Specific histochemical techniques failed to demonstrate different types of chromaffin cells. With the electron microscope two different types of chromaffin cells were observed. The first type, characterised by numerous dense cytoplasmic granules of average diameter 90 nm, was interpreted as a noradrenalin cell; the second type was characterised by the presence of moderately electron-dense granules of average diameter of 85 nm, and was interpreted as an adrenalin cell. The reaction for acetylcholinesterase activity was present on nerve terminals and sometimes in the vacuolar membrane systems of both chromaffin cells. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 PMID:6735912

  2. Evolutionary origin and early biogeography of otophysan fishes (Ostariophysi: Teleostei).

    PubMed

    Chen, Wei-Jen; Lavoué, Sébastien; Mayden, Richard L

    2013-08-01

    The biogeography of the mega-diverse, freshwater, and globally distributed Otophysi has received considerable attention. This attraction largely stems from assumptions as to their ancient origin, the clade being almost exclusively freshwater, and their suitability as to explanations of trans-oceanic distributions. Despite multiple hypotheses explaining present-day distributions, problems remain, precluding more parsimonious explanations. Underlying previous hypotheses are alternative phylogenies for Otophysi, uncertainties as to temporal diversification and assumptions integral to various explanations. We reexamine the origin and early diversification of this clade based on a comprehensive time-calibrated, molecular-based phylogenetic analysis and event-based approaches for ancestral range inference of lineages. Our results do not corroborate current phylogenetic classifications of otophysans. We demonstrate Siluriformes are never sister to Gymnotiformes and Characiformes are most likely nonmonophyletic. Divergence time estimates specify a split between Cypriniformes and Characiphysi with the fragmentation of Pangea. The early diversification of characiphysans either predated, or was contemporary with, the separation of Africa and South America, and involved a combination of within- and between-continental divergence events for these lineages. The intercontinental diversification of siluroids and characoids postdated major intercontinental tectonic fragmentations (<90 Mya). Post-tectonic drift dispersal events are hypothesized to account for their current distribution patterns. PMID:23888847

  3. Complete mitochondrial genome of Schizopygopsis malacanthus (Teleostei: Cypriniformes: Cyprinidae).

    PubMed

    Zeng, Yu; Chen, Yong-Bo; Pan, Bao-Zhu; Zhang, Da-Wen

    2016-03-01

    The complete mitochondrial genome of Schizopygopsis malacanthus is a circular molecule of 16,677?bp in size, containing 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and 2 main non-coding regions (the control region and the origin of the light strand replication). Most of the genes are encoded on the heavy strand, except for ND6 and eight tRNAs. The control region is 938?bp in length and located between the tRNA(Pro) and tRNA(Phe) genes, some typical conserved elements (TAS, CSB1-3 and CSB D-F) were found in this region. All these features reflect a typical vertebrate mitochondrial gene arrangement of the S. malacanthus. PMID:25103444

  4. Phylogenetic placement of enigmatic percomorph families (Teleostei: Percomorphaceae).

    PubMed

    Sanciangco, Millicent D; Carpenter, Kent E; Betancur-R, Ricardo

    2016-01-01

    Percomorphs are a large and diverse group of spiny-finned fishes that have come to be known as the "bush at the top" due to their persistent lack of phylogenetic resolution. Recently, the broader Euteleost Tree of Life project (EToL) inferred a well-supported phylogenetic hypothesis that groups the diversity of percomorphs into nine well-supported series (supraordinal groups): Ophidiaria, Batrachoidaria, Gobiaria, Syngnatharia, Pelagiaria, Anabantaria, Carangaria, Ovalentaria, and Eupercaria. The EToL also provided, for the first time, a monophyletic definition of Perciformes - the largest order of vertebrates. Despite significant progress made in accommodating the diversity of percomorph taxa into major clades, some 62 families (most previously placed in "Perciformes", as traditionally defined) were not examined by the EToL. Here, we provide evidence for the phylogenetic affinities of 10 of those 62 families, seven of which have largely remained enigmatic. This expanded taxonomic sampling also provides further support for the nine EToL supraordinal series. We examined sequences from 21 genes previously used by the EToL and added two fast-evolving mitochondrial markers in an attempt to increase resolution within the rapid percomorph radiations. We restricted the taxonomic sampling to 1229 percomorph species, including expanded sampling from recent studies. Results of maximum likelihood analysis revealed that bathyclupeids (Bathyclupeidae), galjoen fishes (Dichistiidae), kelpfishes (Chironemidae), marblefishes (Aplodactylidae), trumpeters (Latridae), barbeled grunters (Hapalogenyidae), slopefishes (Symphysanodontidae), and picarel porgies (formerly Centracanthidae) are members of the series Eupercaria ("new bush at the top"). The picarel porgies and porgies (Sparidae) are now placed in the same family (Sparidae). Our analyses suggest a close affinity between the orders Spariformes (including Lethrinidae, Nemipteridae and Sparidae) and Lobotiformes (including the tripletails or Lobotidae, the barbeled grunters, and tigerperches or Datnioididae), albeit support for this group is low. None of the newly examined families belong in the order Perciformes, as recently defined. Finally, we confirm results from other recent studies that place the Australasian salmons (Arripidae) within Pelagiaria, and the false trevallies (Lactariidae) close to flatfishes, jacks, and trevallies, within Carangaria. PMID:26493227

  5. The complete mitochondrial genome of Lepturichthys fimbriata (Teleostei, Balitoridae, Balitorinae).

    PubMed

    Xu, Dong-Mei; Yang, Zhi; Xu, Nian; Xiong, Mei-Hua; Lei, Pan; Que, Yan-Fu

    2016-03-01

    Lepturichthys fimbriata is an endemic and an important commercial fish which distributes in the upper stream of the Yangtze River. In this study, the complete mitogenome sequence of L. fimbriata has been first sequenced by DNA sequencing based on the PCR fragments. The mitogenome, consisting of 16,567 base pairs (bp), includes 13 protein coding genes, 22 transfer RNAs, 2 ribosomal RNA genes and a non-coding control region (CR). The overall base composition of L. fimbriata is 30.4% A, 28.7% C, 16.5% G, and 24.4% T, with a relatively a slight AT bias of 54.7%. CR of 903 bp length is located between tRNA(Pro) and tRNA(Phe). The complete mitochondrial genome sequence would be useful for further studies on conservation genetics and resource management in L. fimbriata. PMID:24963762

  6. The complete mitochondrial genome of the Trachinotus ovatus (Teleostei, Carangidae).

    PubMed

    Xie, Zhenzhen; Li, Shuisheng; Yao, Mi; Lu, Danqi; Li, Zhihao; Meng, Zining; Zhang, Yong; Lin, Haoran

    2015-08-01

    We present the complete mitochondrial genome of the Trachinotus ovatus in this study. The mitochondrial genome is 16,563?bp long and consists of 13 protein-coding genes, two rRNA genes, 22 tRNA genes and a control region. The gene order and composition of T. ovatus mitochondrial genome was similar to that of most other vertebrates. The nucleotide compositions of the light strand are 29.03% of A, 28.86% of C, 26.23% of T and 15.88% of G. With the exception of ND6 and eight tRNA genes, all other mitochondrial genes are encoded on the heavy strand. Two copies of tandem repeat sequence (56?bp) was observed in the 5' end of the control region. PMID:24090004

  7. The complete mitochondrial genome of the Hemibagrus guttatus (Teleostei, Bagridae).

    PubMed

    Yang, Huirong; Zhao, Huihong; Xie, Zhenzhen; Sun, Jijia; Yang, Zituo; Liu, Li

    2016-01-01

    The complete mitochondrial genome of the Hemibagrus guttatus was presented in this study. The mitochondrial genome is 16,523?bp long and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region. The gene order and composition of H. guttatus mitochondrial genome was similar to that of most other vertebrates. The nucleotide compositions of the light strand are 31.73% of A, 25.42% of C, 28.02% of T and 14.83% of G. With the exception of the NADH dehydrogenase subunit 6 (ND6) and eight tRNA genes, all other mitochondrial genes are encoded on the heavy strand. PMID:24810069

  8. Reproductive biology of the Panama graysby Cephalopholis panamensis (Teleostei: Epinephelidae).

    PubMed

    Erisman, B E; Craig, M T; Hastings, P A

    2010-04-01

    The reproductive biology of the Panama graysby Cephalopholis panamensis was studied from collections and behavioural observations made in the Gulf of California from 2001 to 2006. Histological examinations, particularly the identification of gonads undergoing sexual transition, confirmed a protogynous hermaphroditic sexual pattern. The population structure and mating behaviour provided further support for protogyny. Size and age distributions by sex were bimodal, with males larger and older than females and sex ratios biased towards females. Mating groups consisted of a large male and several smaller females, and courtship occurred in pairs during the evening. Results on spawning periodicity and seasonality were incomplete, but histological data, monthly gonado-somatic indices (I(G)) and behavioural observations suggest that adults spawned around the full moon from May to September. Certain aspects of their reproductive biology (e.g. protogyny and low egg production) indicate that C. panamensis is particularly vulnerable to fishing and would benefit from a management policy in Mexico. PMID:20537016

  9. The mitogenome of Pangasius sutchi (Teleostei, Siluriformes: Pangasiidae).

    PubMed

    Zhao, Haipeng; Kong, Xianghui; Zhou, Chuanjiang

    2014-10-01

    The Pangasius sutchi is an important ornamental and economic fish in Southeast Asia e.g. Thailand, Malaysia and China. The complete mitochondrial genome sequence of P. sutchi has been sequenced, which contains 22 tRNA genes, 13 protein-coding genes, 2 rRNA genes and a non-coding control region with the total length of 16,522 bp. The gene order and composition are similar to most of other vertebrates. Just like most other vertebrates, the bias of G and C was found in different region/genes statistics results. Most of the genes are encoded on heavy strand, except for eight tRNA and ND6 genes. The mitogenome sequence of P. sutchi would contribute to better understand population genetics, evolution of this lineage. PMID:23795847

  10. Comparative cytogenetics among populations of Hollandichthys multifasciatus (Teleostei: Characidae).

    PubMed

    Balen, Rafael Ernesto; Noleto, Rafael Bueno; Vicari, Marcelo Ricardo; Artoni, Roberto Ferreira; Cestari, Marta Margarete

    2013-02-01

    Two populations of Hollandichthys multifasciatus from headwaters of adjacent river coastal basins in Paran state, southern Brazil, were cytogenetically studied in order to evaluate intraspecific divergences. Both populations presented 2n = 50 chromosomes, divided into 14m + 18sm + 18st in the sample from Antonina and 14m + 20sm + 16st for the population from Guaraqueaba. Analyses of active nucleolar organizer regions (Ag-NORs) and fluorescent in situ hybridization (FISH) with 18S rDNA probes revealed a single metacentric pair bearing marks at proximal positions on the short arms. The location of the 5S rDNA and GC-rich sites showed chromosomal divergence between both populations. Therefore, several population markers were detected, reflecting a population differentiation, possibly driven by the formation of Paranagu Bay and Serra do Mar mountain range. Since the existence of a species complex in H. multifasciatus has been previously characterized by morphological, molecular, and karyotype population differentiation, this species needs to be taxonomically studied in detail. PMID:23387844

  11. Complete mitochondrial genome of Alburnus istanbulensis (Teleostei, Cyprinidae).

    PubMed

    Eldem, Vahap; Kuban, Cneyt; Kuban, Nerdin

    2016-03-01

    Alburnus istanbulensis (Thracian shemaya) is an endemic fish species to the northwestern region of Turkey. Alburnus istanbulensis has a remarkably limited geographic distribution, and no genetic data have been available on this species until now. The mitogenome (16,612?bp) had the typical mitochondrial characteristics of other Leuciscinae fishes. This mitogenome sequence can help to further resolve phylogenetic relationships among Cyprinidae. PMID:25093400

  12. The complete mitochondrial genome of the Culter recurviceps (Teleostei, Cyprinidae).

    PubMed

    Yang, Huirong; Zhao, Huihong; Sun, Jijia; Xie, Zhenzhen; Yang, Zituo; Liu, Li

    2016-01-01

    We present the complete mitochondrial genome of the Culter recurviceps in this study. The mitochondrial genome is 16,622?bp long and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region. The gene order and composition of C. recurviceps mitochondrial genome was similar to that of most other vertebrates. The nucleotide compositions of the light strand are 31.36% of A, 24.77% of T, 27.77% of C and 16.09% of G. With the exception of ND6 and eight tRNA genes, all other mitochondrial genes are encoded on the heavy strand. Two copies of tandem repeat sequence (24?bp) was observed in the end of the 123?bp in control region. PMID:24810061

  13. Complete mitochondrial genome of Gymnodiptychus pachycheilus (Teleostei: Cypriniformes: Cyprinidae).

    PubMed

    Wu, Bo; Deng, Yuanping; Wu, Jiayun; Yan, Chaochao; Song, Zhaobin

    2016-01-01

    The complete mitochondrial DNA genome of Gymnodiptychus pachycheilus was sequenced and characterized. The genome is 16,586?bp in length. As with most teleosts, the mitogenome of G. pachycheilus is structurally conserved, containing two ribosomal RNA (rRNA) genes, 13 protein-coding genes, 22 transfer RNA (tRNA) genes and one displacement loop (D-loop) region. The 12 heavy-strand protein-coding genes of G. pachycheilus and other 15 Schizothoracinae species were used for phylogenetic analysis by Bayesian inference and maximum likelihood methods. The topology demonstrated that G. pachycheilus is relatively close to species in genera of Gymnocypris, Schizopygopsis and Oxygymnocypris but differentiated earlier in Schizothoracinae than them. PMID:24521493

  14. The complete mitochondrial genome of Gymnodiptychus pachycheilus (Teleostei, Cyprinidae, Schizothoracinae).

    PubMed

    Chen, Chunna; Li, Hua; Huang, Yingying; Gong, Quan; Du, Jun

    2016-01-01

    Gymnodiptychus pachycheilus, an endangered cold-water fish belonging to the specialized schizothoracins, is distributed in plateau lakes and the upper reaches of the Yellow and Yangtze Rivers on the northeastern Qinghai-Tibet Plateau in China. In this study, we determined the complete mitogenome sequence of G. pachycheilus. Its complete mitochondrial genome is 16,675?bp in size, and includes 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 control region, which has identical genomic organization and structure to other vertebrates, with the exception of 86?bp non-coding region between tRNA(Thr) and tRNA(Pro). This new complete mitogenome could provide useful data for further studies on stock evaluation and conservation genetics of this species. PMID:24617490

  15. Mitochondrial genome of silver gudgeon, Squalidus argentatus (Teleostei, Cypriniformes).

    PubMed

    Zhou, Qiao; Hu, Ying-Xiong; Ye, Qin; Xue, Yang; Chen, Da-Qing; Li, Yun

    2016-01-01

    In this paper, we first determined the complete mitochondrial genome sequence of Squalidus argentatus, which was 16,607?bp in size and the whole base composition was estimated to be 30.48% A, 25.45% T, 27.36% C, 16.72% G with AT bias of 55.93%. The complete mitogenome comprised 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and 1 control region, with the gene order and content identical to other vertebrate mitogenomes. The complete mitogenome of S. argentatus provides the valuable information for population genetics and phylogeography studies on this species. PMID:24450723

  16. Ampullary electroreceptors in catfish (Teleostei): temperature dependence of stimulus transduction.

    PubMed

    Schfer, K; Braun, H A; Bretschneider, F; Teunis, P F; Peters, R C

    1990-09-01

    The response properties of ampullary electroreceptors have been studied in the catfish Ictalurus nebulosus at skin temperatures between 5 and 35 degrees C. A unimodal relationship between spontaneous activity and temperature was obtained. Mean (+/- SEM) peak discharge rate was 57.3 +/- 1.8 impulses s-1 at 25 degrees C; the receptors were active at 5 degrees C (15.0 impulses s-1) and at 35 degrees C (31.5 impulses s-1). There were no dynamic responses to temperature changes in either the warming or cooling direction. The shape of the frequency characteristic depended on temperature: the peak of the gain curve shifted to low frequencies at low temperatures. There was a concomitant change of the phase characteristic: the intersection at zero degree phase angle shifted to higher frequencies with an increase of temperature, thus increasing the lead at lower frequencies and decreasing the lag at higher frequencies. Latency after combined excitatory and inhibitory impulse stimulation was temperature dependent, ranging from 16.4 ms (5 degrees C) to 5.6 ms (35 degrees C). Application of the specific calcium channel blocker menthol (0.2 mM) suppressed spontaneous activity, the effect becoming more prominent at higher temperatures. Sensitivity to sinusoidal electrical stimulation was also impaired, but to a lesser degree and mainly at lower temperatures. We conclude that the filter properties of the receptor organ can be modelled by a band-pass filter in series with a latency, both of which are temperature dependent. These filter properties might be partially based on the activation kinetics of the transduction channels. PMID:1963489

  17. The complete mitochondrial genome of Jinshaia sinensis (Teleostei, Balitoridae, Balitorinae).

    PubMed

    Que, Yan-Fu; Xu, Dong-Mei; Xiong, Mei-Hua; Yang, Zhi; Gao, Shao-Bo; Shi, Fang

    2016-03-01

    Jinshaia sinensis is an endemic and typical fish which is successfully adaptive to mountain torrents in the upper stream of the Yangtze River and its tributaries. In this study, the complete mitogenome sequence of J. sinensis has been first sequenced by DNA sequencing based on the PCR fragments. The mitogenome, consisting of 16,567 base pairs (bp), had typical vertebrate mitochondrial gene arrangement, including 13 protein coding genes, 22 transfer RNAs, 2 ribosomal RNA genes and a noncoding control region (CR). The overall base composition of J. sinensis is 30.37% A, 28.82% C, 16.59% G, and 24.22% T, with a relatively a slight AT bias of 54.59%. CR of 903?bp length is located between tRNA(Pro) and tRNA(Phe). The complete mitochondrial genome may provide fundamental informative data not only for unravel the population structure and differentiation, but also for further conservation genetics studies on this balitorid species. PMID:24937572

  18. Molecular phylogeny and phylogeography of the Australian freshwater fish genus Galaxiella, with an emphasis on dwarf galaxias (G. pusilla).

    PubMed

    Unmack, Peter J; Bagley, Justin C; Adams, Mark; Hammer, Michael P; Johnson, Jerald B

    2012-01-01

    The freshwater fauna of Southern Australia is primarily restricted to the southwestern and southeastern corners of the continent, and is separated by a large, arid region that is inhospitable to this biota. This geographic phenomenon has attracted considerable interest from biogeographers looking to explain evolutionary diversification in this region. Here, we employed phylogenetic and phylogeographic approaches to evaluate the effect of this barrier on a group of four galaxiid fish species (Galaxiella) endemic to temperate Southern Australia. We also tested if continental shelf width has influenced connectivity among populations during low sea levels when rivers, now isolated, could have been connected. We addressed these questions by sampling each species across its range using multiple molecular markers (mitochondrial cytochrome b sequences, nuclear S7 intron sequences, and 49 allozyme loci). These data also allowed us to assess species boundaries, to refine phylogenetic affinities, and to estimate species ages. Interestingly, we found compelling evidence for cryptic species in G. pusilla, manifesting as allopatric eastern and western taxa. Our combined phylogeny and dating analysis point to an origin for the genus dating to the early Cenozoic, with three of the four species originating during the Oligocene-Miocene. Each Galaxiella species showed high levels of genetic divergences between all but the most proximate populations. Despite extensive drainage connections during recent low sea levels in southeastern Australia, populations of both species within G. pusilla maintained high levels of genetic structure. All populations experienced Late Pleistocene-Holocene population growth, possibly in response to the relaxation of arid conditions after the last glacial maximum. High levels of genetic divergence and the discovery of new cryptic species have important implications for the conservation of this already threatened group of freshwater species. PMID:22693638

  19. Molecular Phylogeny and Phylogeography of the Australian Freshwater Fish Genus Galaxiella, with an Emphasis on Dwarf Galaxias (G. pusilla)

    PubMed Central

    Unmack, Peter J.; Bagley, Justin C.; Adams, Mark; Hammer, Michael P.; Johnson, Jerald B.

    2012-01-01

    The freshwater fauna of Southern Australia is primarily restricted to the southwestern and southeastern corners of the continent, and is separated by a large, arid region that is inhospitable to this biota. This geographic phenomenon has attracted considerable interest from biogeographers looking to explain evolutionary diversification in this region. Here, we employed phylogenetic and phylogeographic approaches to evaluate the effect of this barrier on a group of four galaxiid fish species (Galaxiella) endemic to temperate Southern Australia. We also tested if continental shelf width has influenced connectivity among populations during low sea levels when rivers, now isolated, could have been connected. We addressed these questions by sampling each species across its range using multiple molecular markers (mitochondrial cytochrome b sequences, nuclear S7 intron sequences, and 49 allozyme loci). These data also allowed us to assess species boundaries, to refine phylogenetic affinities, and to estimate species ages. Interestingly, we found compelling evidence for cryptic species in G. pusilla, manifesting as allopatric eastern and western taxa. Our combined phylogeny and dating analysis point to an origin for the genus dating to the early Cenozoic, with three of the four species originating during the Oligocene-Miocene. Each Galaxiella species showed high levels of genetic divergences between all but the most proximate populations. Despite extensive drainage connections during recent low sea levels in southeastern Australia, populations of both species within G. pusilla maintained high levels of genetic structure. All populations experienced Late Pleistocene-Holocene population growth, possibly in response to the relaxation of arid conditions after the last glacial maximum. High levels of genetic divergence and the discovery of new cryptic species have important implications for the conservation of this already threatened group of freshwater species. PMID:22693638

  20. Fine structure of a freshwater teleost (Pimelodus maculatus) intrahepatic biliary pathways.

    PubMed

    Ferri, S

    1982-01-01

    The intrahepatic biliary passages of a teleost liver composed by a muralium duplex was studied by electron microscopy. The bile canaliculus was commonly formed by 2 or more hepatic cells. In the transition zone between the intercellular bile canaliculus and the bile ductule, this duct was formed in part by hepatic cells and in part by duct cells. While the number of duct cells increased, the number of hepatocytes decreased until the entire ductule was formed by 2 or 3 duct cells. Bile duct was formed only by pyramidal duct cells. These cells are readily distinguished from the hepatocytes by its irregular shape, by a paucity of organelles and by the abundance of microfilaments. PMID:7201253

  1. Bioefficacy of some plant derivatives that protect grain against the pulse beetle, Callosobruchus maculatus

    PubMed Central

    Rahman, A.; Talukder, F. A.

    2006-01-01

    Experiments were conducted to study the bioefficacies of different plant/weed derivatives that affect the development of the pulse beetle, Callosobruchus maculates F. (Coleoptera: Bruchidae) fed on black gram, Vigna mungo, seeds. Plant extracts, powder, ash and oil from nishinda (Vitex negundo L.), eucalyptus (Eucalyptus globules Labill.), bankalmi (Ipomoea sepiaria K.), neem (Azadirachta indica L.), safflower (Carthamus tinctorius L.), sesame (Sesamum indicum L.) and bablah (Acacia arabica L.) were evaluated for their oviposition inhibition, surface protectant, residual toxicity and direct toxicity effects on C. maculates. The results showed that plant oils were effective in checking insect infestation. The least number of F1 adults emerged from black gram seeds treated with neem oil. The nishinda oil extract was the most toxic of three extracts tested (nishinda, eucalyptus and bankalmi). Bablah ash was the most effective compared to the powdered leaves of nishinda, eucalyptus and bankalmi. The powdered leaves and extracts of nishinda, eucalyptus and bankalmi, at a 3% mixture, provided good protection for black gram seeds by reducing insect oviposition, F1 adult emergence, and grain infestation rates. The oil treatment did not show adverse effects on germination capability of seeds, even after three months of treatment. PMID:19537990

  2. Eugregarines reduce susceptibility of the hide beetle, Dermestes maculatus, to apicomplexan pathogens and retard larval development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eugregarines are abundant in a great diversity of invertebrates, and yet their relationships with their hosts are subject to controversy and confusion. We tested the effect of the eugregarine, Pyxinia crystalligera, on growth, development, and susceptibility to two Apicomplexa pathogens of the hide ...

  3. Constraints upon the Response of Fish and Crayfish to Environmental Flow Releases in a Regulated Headwater Stream Network

    PubMed Central

    Chester, Edwin T.; Matthews, Ty G.; Howson, Travis J.; Johnston, Kerrylyn; Mackie, Jonathon K.; Strachan, Scott R.; Robson, Belinda J.

    2014-01-01

    In dry climate zones, headwater streams are often regulated for water extraction causing intermittency in perennial streams and prolonged drying in intermittent streams. Regulation thereby reduces aquatic habitat downstream of weirs that also form barriers to migration by stream fauna. Environmental flow releases may restore streamflow in rivers, but are rarely applied to headwaters. We sampled fish and crayfish in four regulated headwater streams before and after the release of summer-autumn environmental flows, and in four nearby unregulated streams, to determine whether their abundances increased in response to flow releases. Historical data of fish and crayfish occurrence spanning a 30 year period was compared with contemporary data (electrofishing surveys, Victoria Range, Australia; summer 2008 to summer 2010) to assess the longer–term effects of regulation and drought. Although fish were recorded in regulated streams before 1996, they were not recorded in the present study upstream or downstream of weirs despite recent flow releases. Crayfish (Geocharax sp. nov. 1) remained in the regulated streams throughout the study, but did not become more abundant in response to flow releases. In contrast, native fish (Gadopsis marmoratus, Galaxias oliros, Galaxias maculatus) and crayfish remained present in unregulated streams, despite prolonged drought conditions during 2006–2010, and the assemblages of each of these streams remained essentially unchanged over the 30 year period. Flow release volumes may have been too small or have operated for an insufficient time to allow fish to recolonise regulated streams. Barriers to dispersal may also be preventing recolonisation. Indefinite continuation of annual flow releases, that prevent the unnatural cessation of flow caused by weirs, may eventually facilitate upstream movement of fish and crayfish in regulated channels; but other human–made dispersal barriers downstream need to be identified and ameliorated, to allow native fish to fulfil their life cycles in these headwater streams. PMID:24647407

  4. Constraints upon the response of fish and crayfish to environmental flow releases in a regulated headwater stream network.

    PubMed

    Chester, Edwin T; Matthews, Ty G; Howson, Travis J; Johnston, Kerrylyn; Mackie, Jonathon K; Strachan, Scott R; Robson, Belinda J

    2014-01-01

    In dry climate zones, headwater streams are often regulated for water extraction causing intermittency in perennial streams and prolonged drying in intermittent streams. Regulation thereby reduces aquatic habitat downstream of weirs that also form barriers to migration by stream fauna. Environmental flow releases may restore streamflow in rivers, but are rarely applied to headwaters. We sampled fish and crayfish in four regulated headwater streams before and after the release of summer-autumn environmental flows, and in four nearby unregulated streams, to determine whether their abundances increased in response to flow releases. Historical data of fish and crayfish occurrence spanning a 30 year period was compared with contemporary data (electrofishing surveys, Victoria Range, Australia; summer 2008 to summer 2010) to assess the longer-term effects of regulation and drought. Although fish were recorded in regulated streams before 1996, they were not recorded in the present study upstream or downstream of weirs despite recent flow releases. Crayfish (Geocharax sp. nov. 1) remained in the regulated streams throughout the study, but did not become more abundant in response to flow releases. In contrast, native fish (Gadopsis marmoratus, Galaxias oliros, Galaxias maculatus) and crayfish remained present in unregulated streams, despite prolonged drought conditions during 2006-2010, and the assemblages of each of these streams remained essentially unchanged over the 30 year period. Flow release volumes may have been too small or have operated for an insufficient time to allow fish to recolonise regulated streams. Barriers to dispersal may also be preventing recolonisation. Indefinite continuation of annual flow releases, that prevent the unnatural cessation of flow caused by weirs, may eventually facilitate upstream movement of fish and crayfish in regulated channels; but other human-made dispersal barriers downstream need to be identified and ameliorated, to allow native fish to fulfil their life cycles in these headwater streams. PMID:24647407

  5. Integrating multiple bioassays to detect and assess impacts of sublethal exposure to metal mixtures in an estuarine fish.

    PubMed

    Barbee, Nicole C; Ganio, Katherine; Swearer, Stephen E

    2014-07-01

    Estuaries are natural sinks for a wide range of urban, industrial and agricultural contaminants that accumulate at potentially toxic but non-lethal concentrations, yet we know relatively little about the long-term impacts of toxicants at these levels on aquatic organisms. In this study, we present an integrated, multi-pronged approach to detect and assess the impacts to estuarine fish of exposure to sublethal concentrations of metal mixtures. Our aims were to (1) examine the effects of sublethal metal exposure on the embryonic development of Galaxias maculatus, an estuarine spawning fish native to southeastern Australia, (2) determine whether sublethal exposure during development has knock-on effects on larval behaviour, and (3) establish whether a signature of metal exposure during embryogenesis can be detected in larval otoliths ("ear bones"). G. maculatus eggs are fertilised in water but develop aerially, in direct contact with estuarine sediments. We were thus also able to explore the relative importance of two exposure pathways, water and sediment. Embryos were exposed to two concentrations of a metal mixture containing Cu, Zn and Pb in water (during fertilisation) and on spiked sediments (during development), using a fully crossed experimental design. Overall, we found that exposure to the metal mixture reduced embryo survival and slowed embryonic development, resulting in poorer quality larvae that exhibited a reduced phototactic response. Differences in exposure to metals between treatment and control embryos were also permanently recorded in the developing otoliths. Combined these three approaches have the potential to be a powerful novel bioassessment tool as they provide a means of identifying a history of metal exposure during the embryonic period and linking it to suboptimal early growth and performance traits which could have long term fitness consequences. PMID:24794343

  6. Balancing genetic uniqueness and genetic variation in determining conservation and translocation strategies: a comprehensive case study of threatened dwarf galaxias, Galaxiella pusilla (Mack) (Pisces: Galaxiidae).

    PubMed

    Coleman, R A; Weeks, A R; Hoffmann, A A

    2013-04-01

    Genetic markers are widely used to define and manage populations of threatened species based on the notion that populations with unique lineages of mtDNA and well-differentiated nuclear marker frequencies should be treated separately. However, a danger of this approach is that genetic uniqueness might be emphasized at the cost of genetic diversity, which is essential for adaptation and is potentially boosted by mixing geographically separate populations. Here, we re-explore the issue of defining management units, focussing on a detailed study of Galaxiella pusilla, a small freshwater fish of national conservation significance in Australia. Using a combination of microsatellite and mitochondrial markers, 51 populations across the species range were surveyed for genetic structure and diversity. We found an inverse relationship between genetic differentiation and genetic diversity, highlighting a long-term risk of deliberate isolation of G.pusilla populations based on protection of unique lineages. Instead, we adopt a method for identifying genetic management units that takes into consideration both uniqueness and genetic variation. This produced a management framework to guide future translocation and re-introduction efforts for G.pusilla, which contrasted to the framework based on a more traditional approach that may overlook important genetic variation in populations. PMID:23432132

  7. Propiedades físicas del gas en regiones de formación estelar multiples en galaxias BCDs: IIZw33 y Mrk600

    NASA Astrophysics Data System (ADS)

    Campuzano-Castro, F.; Hagele, G.; Cardaci, M.; Bosch, G.; Firpo, V.

    2015-08-01

    In this work we perform a detailed analysis of the spectra of the ionized gas belonging to 9 giant HII regions with violent star formation in two Blue Compact Dwarf galaxies. We have measured a large number of recombination and forbidden lines taking into account the underlying stellar population (defining a pseudo continuum for the hydrogen and helium emission lines). The physical properties of the gas have been estimated using the methodology proposed by our group. For the star forming knots, depending on the data available, we derived: (i) the reddening constant from the hydrogen recombination lines in all the regions, (ii) the electron density in the low excitation zone from the sulphur once ionized [SII]6717 and 6731 emission lines ratio, (iii) the electron temperatures using the auroral lines present in the spectra of several of our regions and applying the direct method or empirical relations and photo ionization models: T([OII]), T([OIII]), T([SII]), T([SIII])], and T([NII]) depending on the quality of the spectra, (iv) ionic abundances of He, O, O, S, S, N, Ne, Ar and Ar in most of the knots, except the last one that could only be measured for one object, (v) the total chemical abundances of O, S, N, Ne and Ar, (vi) the ionization degree from the softness parameter .

  8. Fine structure and intercellular junctions of a freshwater teleost (Pimelodus maculatus) hepatocytes by freeze-fracture replicas.

    PubMed

    Ferri, S; de Brito-Ingles Bonates, A

    1981-01-01

    The Pt-C replicas of a freshwater teleost hepatic cells were studied by electron microscopy. The surface of hepatocytes bordering the perisinusoidal space is studied with numerous microvilli. Cell-to-cell attachments are made through gap junctions and spot desmosomes. Tight junctions are found between hepatocytes close to the bile canaliculi. Some of the numerous corpuscular elements found in the cytoplasm can be identified as organelles, specially if their interiors are partially exposed by cleaving. PMID:7250650

  9. Antagonistic Regulation, Yet Synergistic Defense: Effect of Bergapten and Protease Inhibitor on Development of Cowpea Bruchid Callosobruchus maculatus

    PubMed Central

    Sun, Yucheng; Chi, Yong Hun; Ge, Feng; Patil, Bhimanagouda S.; Koiwa, Hisashi; Zeng, Rensen; Zhu-Salzman, Keyan

    2012-01-01

    The furanocoumarin compound bergapten is a plant secondary metabolite that has anti-insect function. When incorporated into artificial diet, it retarded cowpea bruchid development, decreased fecundity, and caused mortality at a sufficient dose. cDNA microarray analysis indicated that cowpea bruchid altered expression of 543 midgut genes in response to dietary bergapten. Among these bergapten-regulated genes, 225 have known functions; for instance, those encoding proteins related to nutrient transport and metabolism, development, detoxification, defense and various cellular functions. Such differential gene regulation presumably facilitates the bruchids' countering the negative effect of dietary bergapten. Many genes did not have homology (E-value cutoff 10−6) with known genes in a BlastX search (206), or had homology only with genes of unknown function (112). Interestingly, when compared with the transcriptomic profile of cowpea bruchids treated with dietary soybean cysteine protease inhibitor N (scN), 195 out of 200 coregulated midgut genes are oppositely regulated by the two compounds. Simultaneous administration of bergapten and scN attenuated magnitude of change in selected oppositely-regulated genes, as well as led to synergistic delay in insect development. Therefore, targeting insect vulnerable sites that may compromise each other's counter-defensive response has the potential to increase the efficacy of the anti-insect molecules. PMID:22927917

  10. Combined effect of three insect growth regulators on the digestive enzymatic profiles of Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Khatter, Najat Aly; Abuldahb, Faten Farid

    2011-12-01

    Insect growth regulators (IGRs) are insecticides that mimic insect produced hormones by regulatingdevelopmental process. Theyhave little or no mammalian toxicity, and are considered reduced-risk insecticides that are often exempt from tolerance requirements of regulatory agencies. IGRs, especially, chlorfluazuron, hydroprene and hexaflumuron (benzoylphenylurea) are currently studied because of possibility of using in stored products protection. Many of IGRs compounds usedin insect pests control are known to affect digestive enzymes. Chlorfluazuron, hydroprene and hexaflumuronwere tested topically at doses of 0.25%, 0.5%&1% for chlorfluazuron and hydroprene and 0.5, 1 & 2 microg/ml of hexaflumuron to investigate its effects on the activities of the digestive enzymes protease, amylase and lipase in Callosobruchusmaculatus larvae, which were affected by IGRs individually and in combination. When combined, the effect was more sever at low concentration. There were statistically significant differences (P < or = 0.05) in enzyme activities in combined and individual treatments. Combination three IGRs caused a two-fold decrease in enzyme activity even at reduced concentration. Clear dose-response relationships were established with respect to enzyme activity. A synergistic effect of IGRs was found by combination of low doses. These effects are most pronounced in early instars. PMID:22435168

  11. Profundulus kreiseri, a new species of Profundulidae (Teleostei, Cyprinodontiformes) from northwestern Honduras

    PubMed Central

    Matamoros, Wilfredo A.; Schaefer, Jacob F.; Hernández, Carmen L.; Prosanta Chakrabarty

    2012-01-01

    Abstract A new species of Profundulus, Profundulus kreiseri (Cyprinodontiformes: Profundulidae), is described from the Chamelecón and Ulúa Rivers in the northwestern Honduran highlands. Based on a phylogenetic analysis using cytochrome b and the presence of synapomorphic characters (dark humeral spot, a scaled preorbital region and between 32-34 vertebrae), this new species is placed in the subgenus Profundulus, which also includes Profundulus (Profundulus) oaxacae, Profundulus (Profundulus) punctatus and Profundulus (Profundulus) guatemalensis. Profundulus kreiseri can be distinguished from other members of the subgenus Profundulus by having less than half of its caudal fin densely scaled. Profundulus kreiseri can further be differentiated from Profundulus (Profundulus) oaxacae and Profundulus (Profundulus) punctatus by the absence of rows of dark spots on its flanks. The new species can further be differentiated from Profundulus (Profundulus) guatemalensis by the presence of fewer caudal- and pectoral-fin rays. The new species is distinguished from congeners of the profundulid subgenus Tlaloc (viz., Profundulus (Tlaloc) hildebrandi, Profundulus (Tlaloc) labialis, Profundulus (Tlaloc) candalarius and Profundulus (Tlaloc) portillorum) by having a scaled preorbital region and a dark humeral spot. Profundulus kreiseri and Profundulus portillorum are the only two species of Profundulus that are endemic to the region south of the Motagua River drainage in southern Guatemala and northwestern Honduras. PMID:23166464

  12. Two new species of the South Asian catfish genus Pseudolaguviafrom northeastern India (Teleostei: Sisoridae).

    PubMed

    Tamang, Lakpa; Sinha, Bikramjit

    2014-01-01

    Two new species of sisorid catfish, Pseudolaguvia magna and P. jiyaensis, are described from the upper Brahmaputra River basin in Arunachal Pradesh, northeastern India. Pseudolaguvia magna differs from its congeners by its much larger size (47.0 mm standard length vs. a maximum of 35.6 mm), by having a broader rhomboid thoracic adhesive apparatus, two pale-brown or cream patches on the mid-dorsal region across the dorsal midline: one rectangular to elliptic patch on the mid-interdorsal region, and another indistinct elliptic to irregular patch between the adipose and caudal-fins; and a small, round, pale-brown to cream spot on the lateral side of the head; and except for P. inornata, P. austrina, P. virgulata, and P. assula, in lacking pale to cream cross-bands on the body. Another syntopic new species, Pseudolaguvia jiyaensis, is distinguished from its congeners by having the thoracic adhesive apparatus almost reaching the pelvic-fin origin, and by having fewer vertebrae (25-27 vs. 28-34; except in P. tenebricosa and P. tuberculata). Details of the combination of characters differentiating each of the new species from its congeners are provided in the respective diagnoses. PMID:25543922

  13. Electric Signals in the Social Behavior of Sympatric Elephantfish (Mormyridae, Teleostei) from the Upper Zambezi River

    NASA Astrophysics Data System (ADS)

    Scheffel, A.; Kramer, B.

    Electrocommunication in mormyrid fish from African freshwaters is a challenging research field in neuroethology (Turner et al. 1999). However, virtually nothing is known about electrocommunication within natural mormyrid populations involving sympatric, syntopic species. Here we report on the nocturnal activities and electrocommunication among three syntopic species in a spacious laboratory setting resembling the natural one. Petrocephalus catostoma, Cyphomyrus discorhynchus, and Hippopotamyrus sp. nov. differ characteristically in their behavior, such as in territorial defense, schooling, and joining members of other species during foraging. Comparing social encounters within and between species, the first evidence for interspecific electrocommunication among syntopic species was found.

  14. Spermatozoa ultrastructure in Sciaenidae and Polynemidae (Teleostei:Perciformes) with some consideration on Percoidei spermatozoa ultrastructure.

    PubMed

    Gusmo-Pompiani, P; Oliveira, C; Quagio-Grassiotto, I

    2005-06-01

    Spermatozoa ultrastructure was studied in five marines (Paralonchurus brasiliensis, Larimus breviceps, Cynoscion striatus, Micropogonias furnieri, Menticirrhus americanus, Umbrina coroides, Stellifer rastrifer), and one freshwater (Plagioscion squamosissimus) species of Sciaenidae and one species of Polynemidae (Polydactylus virginicus). The investigation revealed that, in all species, spermatozoa display a round head, a nucleus containing highly condensed, filamentous chromatin clusters, no acrosome, a short midpiece with a short cytoplasmic channel, and a flagellum showing the classic axoneme structure (9+2) and short irregular lateral fins. In Sciaenidae, the spermatozoa are type II, the flagellar axis is parallel to the nucleus, the lateral nuclear fossa is double arched, the centriolar complex is outside the nuclear fossa, the proximal centriole is anterior and perpendicular to the distal centriole, and no more than ten spherical (marine species) or elongate (freshwater species) mitochondria are observed. Polynemidae spermatozoa are of the intermediate type with the flagellar axis eccentric to the hemi-arc-shaped nucleus, and exhibit no nuclear fossa, the centriolar complex close to the upper nuclear end, the proximal centriole lateral and oblique to the distal centriole, and one large ring-shaped mitocondrion. The data available show that no characteristic is exclusively found in the spermatozoa of members of the Sciaenidae family when compared to other Percoidei with type II spermatozoa. However, three characteristics were exclusively found in Polynemidae: (1) the hemi-arched nucleus; the positioning of the centrioles; and (2) the ring-shaped mitocondrion. The interrelationships between Sciaenidae and Polynemidae as well as between these two families and other Percoidei are herein discussed. PMID:15936355

  15. Why is Pseudosphromenus cupanus (Teleostei: Osphronemidae) reported from Bangladesh, Indonesia, Malaysia, Myanmar, and Pakistan?

    PubMed

    Kullander, Sven O; Rahman, Md Mizanur; Norén, Michael; Mollah, Abdur Rob

    2015-01-01

    The native distribution of the small labyrinth fish species Pseudosphromenus cupanus includes southern India and Sri Lanka. According to literature it has a range including also Pakistan, Bangladesh, Myanmar, Malaysia, and Indonesia (Sumatra) but there are no voucher specimens or reliable observations from those areas. The distribution record of P. cupanus was inflated partly by including P. dayi as a synonym. Pseudosphronemus dayi is native to the Western Ghats in India, but the origin of the aquarium importation in 1907 was reported as both Cochin (=Kochi) and Malacca (=Malaysia), the latter locality obviously in error. The basis for the Sumatra record is an obviously mislabeled sample of P. dayi from Pulau Weh close to Sumatra. The basis for reporting the species from Pakistan, Myanmar or Bangladesh could not be located. Misidentified museum specimens from Myanmar and Pakistan identified as P. cupanus were never published on. Pseudosphromenus cupanus has been considered recently to be extinct in Bangladesh, but in fact it never occurred there. PMID:26250251

  16. Gonadal morphogenesis and sex differentiation in the viviparous fish Chapalichthys encaustus (Teleostei, Cyprinodontiformes, Goodeidae).

    PubMed

    Guerrero-Estvez, S; Moreno-Mendoza, N

    2012-03-01

    This study describes the structural and ultrastructural characteristics of gonadal sex differentiation and expression of Vasa, a germline marker, in different developmental stages of embryos and newborn fry of the barred splitfin Chapalichthys encaustus, a viviparous freshwater teleost endemic to Mexico. In stage 2 embryos, the gonadal crest was established; gonadal primordia were located on the coelomic epithelium, formed by scarce germ and somatic cells. At stage 3, the undifferentiated gonad appeared suspended from the mesentery of the developing swimbladder and contained a larger number of germ and somatic cells. At stages 4 and 5, the gonads had groups of meiotic and non-meiotic germ cells surrounded by somatic cells; meiosis was evident from the presence of synaptonemal complexes. These stages constituted a transition towards differentiation. At stage 6 and at birth, the gonad was morphologically differentiated into an ovary or a testis. Ovarian differentiation was revealed by the presence of follicles containing meiotic oocytes, and testicular differentiation by the development of testicular lobules containing spermatogonia in mitotic arrest, surrounded by Sertoli cells. Nuage, electron-dense material associated with mitochondria, was observed in germ cells at all gonadal stages. The Vasa protein was detected in all of the previously described stages within the germ-cell cytoplasm. This is the first report on morphological characteristics and expression of the Vasa gene during sexual differentiation in viviparous species of the Goodeidae family. Chapalichthys encaustus may serve as a model to study processes of sexual differentiation in viviparous fishes and teleosts. PMID:22380554

  17. Structure and function of placental exchange surfaces in goodeid fishes (Teleostei: Atheriniformes).

    PubMed

    Schindler, Joachim F

    2015-08-01

    The species of the family Goodeidae have evolved reproductive strategies involving intraovarian gestation, early evacuation of nearly yolk-exhausted embryos from the ovigerous tissue into the ovarian cavity, placental matrotrophy during intraluminal gestation, and the birth of highly developed fry. The inner ovarian lining becomes hypervascularized during gestational periods and functions as the maternal component of the placental association. Embryotrophic liquid is secreted by the inner ovarian epithelium into the ovarian cavity. Comparative electrophoretic analyses of embryotrophe and maternal blood serum provide evidence for the transfer of maternal serum proteins into the embryotrophe. Trophotaeniae, proctodaeal processes of the embryos, provide a surface for nutrient absorption. Endocytic activity was demonstrated by ingestion of unspecific tracer proteins in various species. Moreover, the trophotaenial absorptive cells (TACs) in Ameca splendens ingest various proteins or random copolymers conjugated to colloidal gold as well as radioiodinated proteins in a way that satisfies the criteria of receptor-mediated endocytosis. Several aminopeptidases (APs) on the surface of TACs were identified as protein binding sites as evidenced by inhibition of binding and uptake of marker proteins in the presence of AP substrates or AP inhibitors. Morphological adaptations of the embryonic circulatory system pertaining to nutrient and gas exchange were characterized. The embryonic epidermis comprises two layers of squamous cells closely underlain by a dense capillary net. Efficient gas exchange is facilitated by a thin embryotrophe-blood barrier of both the embryonic skin and the intraovarian lining. PMID:24797516

  18. Stages in the early and larval development of the African catfish Clarias gariepinus (Teleostei, Clariidae).

    PubMed

    Olaniyi, Wasiu Adekunle; Omitogun, Ofelia Galman

    2014-08-01

    The African catfish Clarias gariepinus Burchell 1822 is a favourite aquaculture fish in many parts of Africa and Asia because of its hardiness and fast growth rate. In this study, early, post-embryonic and larval developmental stages of C. gariepinus were examined chronologically and described. Photomicrographs of unfertilized matured oocytes from 0 min of fertilization through all cell stages to alevin, to complete yolk absorption, to free swimming larval stages are shown and documented live from lateral and top views, with the aid of a light microscope. Extruded oocytes had a mean diameter of 1 0.1 mm, and possessed a thin perivitelline membrane whose space was filled with a protoplasmic layer. Heartbeat was in the range of 115-160/min prior to hatching. Hatchability rate was 85% and hatching occurred at 17 h at a controlled temperature of 28.5 0.5C, while ontogeny of the eyes and other organs were discernible. At day 4, larvae mean length was 9.3 0.5 mm, exogenous feeding had commenced fully and melanophores spread cephalocaudally but were concentrated significantly on the head parts. This paper, for the first time, presents the significant chronological developmental stages of C. gariepinus embryology that will have significant implications for genetic manipulation and catfish seed production for aquaculture. PMID:23534899

  19. Stressful and behavioral conditions that affect reversible cardiac arrest in the Nile tilapia, Oreochromis niloticus (Teleostei).

    PubMed

    Ide, Liliam Midori; Hoffmann, Anette

    The objective of the present investigation was to study the reversible cardiac arrest (RCA) to visual stimuli in the unrestrained Nile tilapia (Oreochromis niloticus) as well as the modulation of this response and its behavioral component (arousal/orientation or startle response) by external and internal factors that interfere with alertness and emotionality. The study was preceded by the determination of the autonomic receptors that contribute to the establishment of the heart rate (HR) and the RCA. Systemic injection of atropine and propranolol showed that a double cardiac autonomic control is present in the tilapia. Basal HR was 79.8+/-1.8 beats min(-1) and HR assessed after double autonomic blockade was 74.1+/-3.3 beats min(-1). The mean interbeat interval was 0.79+/-0.40 s during baseline recording and the magnitude of RCA induced by a moving shadow (2.67+/-0.22 s) was higher than that induced by light (1.53+/-1.11 s). RCA is peripherally mediated by muscarinic receptors for it is abolished by atropine but not by propranolol. Stressful conditions like handling the animal outside the water or a nociceptive stimulus (subcutaneous 2% or 3% formalin injection) reduced the cardiac interbeat interval. A subanesthetic dose of barbiturate (5 mg kg(-1)) inhibited RCA induced by a moving shadow stimulus and the startle response, suggesting that an ideal degree of vigilance is necessary for its occurrence. Benzodiazepine injections (1.0 and 2.0 mg kg(-1)) abolished the reduction in magnitude of RCA induced by handling stress and facilitated the startle response, seen in the dry-cold season, in a dose-dependent manner. These data suggest that drugs that act on alertness and on emotionality modulate the magnitude of cardiac interbeat intervals and the corresponding behavioral response. PMID:11890960

  20. Chromosomal location of retrotransposable REX 1 in the genomes in five Prochilodus (Teleostei

    PubMed Central

    Voltolin, Tatiana Aparecida; Mendona, Bruna Bueno; Ferreira, Daniela Cristina; Senhorini, Jos Augusto; Foresti, Fausto; Porto-Foresti, Fbio

    2013-01-01

    Transposable elements are repetitive DNA sequences comprising a group of segments able to move and carry sequences within the genome. Studies involving comparative genomics have revealed that most vertebrates have different populations of transposable elements with significant differences among species of the same lineage. Few studies have been conducted in fish, the most diverse group of vertebrates, with the objective to locate different types of transposable elements. Therefore, this study proposed to map the retrotransposable element Rex1 applying Fluorescent in situ Hybridization (FISH) in five species of the genus Prochilodus (Prochilodus argenteus, Prochilodus brevis, Prochilodus costatus, Prochilodus lineatus and Prochilodus nigricans). After the application of the Rex1 probe, scattered markings were found throughout the genome of analyzed species, and also the presence of small clusters located in the centromeric and telomeric regions coincident with the heterochromatin distribution pattern. This was the first description of the retrotransposable element Rex1 in Prochilodus genome seeking for a better understanding of the distribution pattern of these retrotransposons in the genome of teleost fish. PMID:24195015

  1. The complete mitogenome of the river blackfish, Gadopsis marmoratus (Richardson, 1848) (Teleostei: Percichthyidae).

    PubMed

    Gan, Han Ming; Tan, Mun Hua; Lee, Yin Peng; Austin, Christopher M

    2014-10-20

    Abstract The mitogenome of the Australian freshwater blackfish, Gadopsis marmoratus was recovered coverage by genome skimming using the MiSeq sequencer (GenBank Accession Number: NC_024436). The blackfish mitogenome has 16,407 base pairs made up of 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs, and a 819?bp non-coding AT-rich region. This is the 5th mitogenome sequence to be reported for the family Percichthyidae. PMID:25329292

  2. Phylogeny and polyploidy: resolving the classification of cyprinine fishes (Teleostei: Cypriniformes).

    PubMed

    Yang, Lei; Sado, Tetsuya; Vincent Hirt, M; Pasco-Viel, Emmanuel; Arunachalam, M; Li, Junbing; Wang, Xuzhen; Freyhof, Jörg; Saitoh, Kenji; Simons, Andrew M; Miya, Masaki; He, Shunping; Mayden, Richard L

    2015-04-01

    Cyprininae is the largest subfamily (>1300 species) of the family Cyprinidae and contains more polyploid species (∼400) than any other group of fishes. We examined the phylogenetic relationships of the Cyprininae based on extensive taxon, geographical, and genomic sampling of the taxa, using both mitochondrial and nuclear genes to address the phylogenetic challenges posed by polyploidy. Four datasets were analyzed in this study: two mitochondrial gene datasets (465 and 791 taxa, 5604bp), a mitogenome dataset (85 taxa, 14,771bp), and a cloned nuclear RAG1 dataset (97 taxa, 1497bp). Based on resulting trees, the subfamily Cyprininae was subdivided into 11 tribes: Probarbini (new; Probarbus+Catlocarpio), Labeonini Bleeker, 1859 (Labeo & allies), Torini Karaman, 1971 (Tor, Labeobarbus & allies), Smiliogastrini Bleeker, 1863 (Puntius, Enteromius & allies), Poropuntiini (Poropuntius & allies), Cyprinini Rafinesque, 1815 (Cyprinus & allies), Acrossocheilini (new; Acrossocheilus & allies), Spinibarbini (new; Spinibarbus), Schizothoracini McClelland, 1842 (Schizothorax & allies), Schizopygopsini Mirza, 1991 (Schizopygopsis & allies), and Barbini Bleeker, 1859 (Barbus & allies). Phylogenetic relationships within each tribe were discussed. Two or three distinct RAG1 lineages were identified for each of the following tribes Torini, Cyprinini, Spinibarbini, and Barbini, indicating their hybrid origin. The hexaploid African Labeobarbus & allies and Western Asian Capoeta are likely derived from two independent hybridization events between their respective maternal tetraploid ancestors and Cyprinion. PMID:25698355

  3. Molecular phylogeny and conservation priorities of the subfamily Acheilognathinae (Teleostei: Cyprinidae).

    PubMed

    Cheng, Peilin; Yu, Dan; Liu, Siqing; Tang, Qiongying; Liu, Huanzhang

    2014-05-01

    It is increasingly accepted that conservation work should consider the evolutionary history of target species. Fishes in the subfamily Acheilognathinae, family Cyprinidae, are, with the exception of three species exclusively distributed in Europe, restricted to Asia and show a distinct spawning behavior in laying their eggs in gill chambers of freshwater mussels. At present, many of the 70 species recognized in this group are facing with serious population decline in China and Japan, and their phylogenetic relationships are not well resolved. In the present study, based on mtDNA cyt b and 12S rRNA gene sequences, we reconstructed a more detailed species-level phylogenetic tree of this group, and assessed species conservation priorities based on their evolutionary distinctiveness. Molecular phylogenetic analyses showed that the Acheilognathinae contains two major clades: Acheilognathus clade and Tanakia-Rhodeus clade. Based on this phylogenetic result, conservation priority analyses were conducted using ED (evolutionary distinctiveness)/HED (heightened evolutionary distinctiveness), and EDGE (evolutionary distinctiveness and global endangeredness)/HEDGE (heightened evolutionary distinctiveness and global endangeredness) methods. The results suggested that T. himantegus, T. lanceolata, A. gracilis, A. imberbis, T. tanago, and A. longipinnis should be ranked as the top-priority species for conservation. According to our results, we also discussed the current conservation efforts of the bitterling fishes and gave suggestions for future work. PMID:24832903

  4. Gaidropsarus (Gadidae, Teleostei) of the North Atlantic Ocean: a brief phylogenetic review.

    PubMed

    Francisco, S M; Robalo, J I; Stefanni, S; Levy, A; Almada, V C

    2014-08-01

    The phylogenetic relationships among the North Atlantic Gaidropsarus and between the three Gaidropsarinae genera Gaidropsarus, Ciliata and Enchelyopus are reviewed with the hitherto most comprehensive taxonomic sampling of this group. Phylogenetic results (maximum parsimony, maximum likelihood and Bayesian inference) based on nuclear (rhodopsin) and concatenated mitochondrial (12s, 16s and cytb) markers clearly support this subfamily. For the north-eastern Atlantic species of Gaidropsarus, two previously unreported clades were strongly supported, clarifying the relationships within the genus, and revealing fewer distinct taxa in the north Atlantic Gaidropsarus than previously stipulated. The data challenge the specific status of Gaidropsarus mediterraneus and Gaidropsarus guttatus and raise doubts concerning the distinctiveness of other species. A taxonomic revision of the genus is suggested. PMID:24961593

  5. Transcriptome analysis of vertebral bone in the flounder, Paralichthys olivaceus (Teleostei, Pleuronectiformes), using Illumina sequencing.

    PubMed

    Ibaraki, Harumi; Wu, Xiaoming; Uji, Susumu; Yokoi, Hayato; Sakai, Yoshifumi; Suzuki, Tohru

    2015-12-01

    The processes underlying vertebral development in teleosts and tetrapods differ markedly in a variety of ways. At present, the molecular basis of teleost vertebral development and growth is poorly understood. Understanding vertebral development at the molecular level is important for aquaculture to prevent vertebral anomalies that can arise from a variety of factors, including excess vitamin A (all-trans retinol, VA) in the diet. To facilitate studies on teloest vertebral development, we performed transcriptome analysis of four month old flounder, Paralichthys olivaceus, vertebrae using next-generation sequencing. Expression profile obtained demonstrates that some members of the hh, bmp, fgf, wnt gene families, and their receptors, hox, pax, sox, dlx and tbx gene families and ntl, which are known to function in notochord and somite development in embryos, are expressed in the vertebrae. It was also showed that in addition to the retinoic acid receptor (Rar), the vertebrae express alcohol dehydrogenase 1 and retinal dehydrogenase 2 which convert VA to all-trans-retinoic acid (RA). The assembled contigs also included cytochrome p450 family members, which inactivate RA, as well as phosphatidylcholine-retinol O-acetyltransferase, which converts VA to all-trans-retinyl ester, a stock form of VA. These data suggest that in teleost vertebrae, expression of various signals and transcription factors which function in the notochord and somite development is maintained until adult stage, and RA metabolism and signaling are active to regulate transcription of RA-responsible genes, such as hedgehog and hox genes. This is the first transcriptome analysis of teleost fish vertebrae. PMID:26452303

  6. Autonomic control of post-air-breathing tachycardia in Clarias gariepinus (Teleostei: Clariidae).

    PubMed

    Teixeira, Mariana Teodoro; Armelin, Vinicius Araújo; Abe, Augusto Shinya; Rantin, Francisco Tadeu; Florindo, Luiz Henrique

    2015-08-01

    The African catfish (Clarias gariepinus) is a teleost with bimodal respiration that utilizes a paired suprabranchial chamber located in the gill cavity as an air-breathing organ. Like all air-breathing fishes studied to date, the African catfish exhibits pronounced changes in heart rate (f H) that are associated with air-breathing events. We acquired f H, gill-breathing frequency (f G) and air-breathing frequency (f AB) in situations that require or do not require air breathing (during normoxia and hypoxia), and we assessed the autonomic control of post-air-breathing tachycardia using an infusion of the β-adrenergic antagonist propranolol and the muscarinic cholinergic antagonist atropine. During normoxia, C. gariepinus presented low f AB (1.85 ± 0.73 AB h(-1)) and a constant f G (43.16 ± 1.74 breaths min(-1)). During non-critical hypoxia (PO2 = 60 mmHg), f AB in the African catfish increased to 5.42 ± 1.19 AB h(-1) and f G decreased to 39.12 ± 1.58 breaths min(-1). During critical hypoxia (PO2 = 20 mmHg), f AB increased to 7.4 ± 1.39 AB h(-1) and f G decreased to 34.97 ± 1.78 breaths min(-1). These results were expected for a facultative air breather. Each air breath (AB) was followed by a brief but significant tachycardia, which in the critical hypoxia trials, reached a maximum of 143 % of the pre-AB f H values of untreated animals. Pharmacological blockade allowed the calculation of cardiac autonomic tones, which showed that post-AB tachycardia is predominantly regulated by the parasympathetic subdivision of the autonomic nervous system. PMID:25982049

  7. Pempheris gasparinii, a new species of sweeper fish from Trindade Island, southwestern Atlantic (Teleostei, Pempheridae)

    PubMed Central

    Pinheiro, Hudson T.; Bernardi, Giacomo; Rocha, Luiz A.

    2016-01-01

    Abstract Pempheris gasparinii sp. n. is described from five specimens, 59.1–68.0 mm in standard length. It is only known to occur in the shallow reefs of Trindade Island, 1200 km east of the Brazilian coast, in the southwestern Atlantic. Pempheris gasparinii is the third recognized species of Pempheris in the Atlantic Ocean. This new species is morphologically similar to its close relative, Pempheris poeyi, differing by the number of lateral-line scales (51–54 in Pempheris gasparinii vs. 47–49 in Pempheris poeyi), scales below lateral line (10–11 vs. 9), circumpeduncular scales (11–12 vs. 13), head and caudal peduncle lengths (2.7–3.3 vs 3.5–4.0 in head length). Moreover, Pempheris gasparinii shows a 4% genetic divergence from Pempheris poeyi at the cytochrome oxidase I locus (COI), consistent with a lineage split at the beginning of the Pleistocene. This new species represents the 12th endemic fish species from Trindade Island. PMID:27006618

  8. Phylogeny and biogeography of a shallow water fish clade (Teleostei: Blenniiformes)

    PubMed Central

    2013-01-01

    Background The Blenniiformes comprises six families, 151 genera and nearly 900 species of small teleost fishes closely associated with coastal benthic habitats. They provide an unparalleled opportunity for studying marine biogeography because they include the globally distributed families Tripterygiidae (triplefin blennies) and Blenniidae (combtooth blennies), the temperate Clinidae (kelp blennies), and three largely Neotropical families (Labrisomidae, Chaenopsidae, and Dactyloscopidae). However, interpretation of these distributional patterns has been hindered by largely unresolved inter-familial relationships and the lack of evidence of monophyly of the Labrisomidae. Results We explored the phylogenetic relationships of the Blenniiformes based on one mitochondrial (COI) and four nuclear (TMO-4C4, RAG1, Rhodopsin, and Histone H3) loci for 150 blenniiform species, and representative outgroups (Gobiesocidae, Opistognathidae and Grammatidae). According to the consensus of Bayesian Inference, Maximum Likelihood, and Maximum Parsimony analyses, the monophyly of the Blenniiformes and the Tripterygiidae, Blenniidae, Clinidae, and Dactyloscopidae is supported. The Tripterygiidae is the sister group of all other blennies, and the Blenniidae is the sister group of the remaining blennies. The monophyly of the Labrisomidae is supported with the exclusion of the Cryptotremini and inclusion of Stathmonotus, and we elevate two subgenera of Labrisomus to establish a monophyletic classification within the family. The monophyly of the Chaenopsidae is supported with the exclusion of Stathmonotus (placed in the Stathmonotini) and Neoclinus and Mccoskerichthys (placed in the Neoclinini). The origin of the Blenniiformes was estimated in the present-day IndoPacific region, corresponding to the Tethys Sea approximately 60.3 mya. A largely Neotropical lineage including the Labrisomidae, Chaenopsidae and Dactyloscopidae (node IV) evolved around 37.6 mya when the Neotropics were increasingly separated from the IndoPacific, but well before the closure of the Tethys Sea. Conclusions Relationships recovered in this study are similar to those of earlier analyses within the Clinidae and Chaenopsidae, and partially similar within the Blenniidae, but tripterygiid relationships remain poorly resolved. We present the first comprehensive phylogenetic hypothesis for a monophyletic Labrisomidae with five tribes (Labrisomini, Mnierpini, Paraclinini, Stathmonotini and Starksiini). Global distributions of blenny genera included in our analysis support the evolution of a largely Neotropical clade whose closest relatives (clinids and cryptotremines) are temperate in distribution. PMID:24067147

  9. Intersexuality of Scomberomorus niphonius from the Coastal Area around Jeju Island, Korea (Teleostei: Scombridae)

    PubMed Central

    Kim, Jong Bin; Chang, Dae Soo; Kim, Hyejin; Jeon, Mi Ae; Ku, Kayeon; Lee, Jung Sick

    2013-01-01

    This study histologically describes the intersexuality of Scomberomorus niphonius collected from the coastal area near Jeju Island. A total of 126 S. niphonius, collected from March to July 2012 with a total length of 62.4 cm (17.5) and a total weight of 1,701.9 g (1,528.9) were used for analyses. From a histological perspective, two types of intersex were confirmed. One type had scattered germ cells from the opposite sex within the gonad. The second type developed germ cells from the opposite sex in the connective tissue of the outer gonadal membrane. The intersexuality was 14.3% (n=18/126), with females (21.3%; n=16/75) exhibiting a higher rate than males (3.9%; n=2/51). There was no displayed correlation between intersexuality and the total length and weight. PMID:25949123

  10. Repetitive DNA Sequences and Evolution of ZZ/ZW Sex Chromosomes in Characidium (Teleostei: Characiformes)

    PubMed Central

    Pansonato-Alves, José Carlos; da Costa Silva, Guilherme José; Vicari, Marcelo Ricardo; Artoni, Roberto Ferreira; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    Characidium constitutes an interesting model for cytogenetic studies, since a large degree of karyotype variation has been detected in this group, like the presence/absence of sex and supernumerary chromosomes and variable distribution of repetitive sequences in different species/populations. In this study, we performed a comparative cytogenetic analysis in 13 Characidium species collected at different South American river basins in order to investigate the karyotype diversification in this group. Chromosome analyses involved the karyotype characterization, cytogenetic mapping of repetitive DNA sequences and cross-species chromosome painting using a W-specific probe obtained in a previous study from Characidium gomesi. Our results evidenced a conserved diploid chromosome number of 2n = 50, and almost all the species exhibited homeologous ZZ/ZW sex chromosomes in different stages of differentiation, except C. cf. zebra, C. tenue, C. xavante and C. stigmosum. Notably, some ZZ/ZW sex chromosomes showed 5S and/or 18S rDNA clusters, while no U2 snDNA sites could be detected in the sex chromosomes, being restricted to a single chromosome pair in almost all the analyzed species. In addition, the species Characidium sp. aff. C. vidali showed B chromosomes with an inter-individual variation of 1 to 4 supernumerary chromosomes per cell. Notably, these B chromosomes share sequences with the W-specific probe, providing insights about their origin. Results presented here further confirm the extensive karyotype diversity within Characidium in contrast with a conserved diploid chromosome number. Such chromosome differences seem to constitute a significant reproductive barrier, since several sympatric Characidium species had been described during the last few years and no interespecific hybrids were found. PMID:26372604

  11. Cytogenetic analysis of two locariid species (Teleostei, Siluriformes) from Iguatemi River (Parana River drainage) in Brazil

    PubMed Central

    Fernandes, Carlos Alexandre; Alves, Diandra Soares; Guterres, Zaira da Rosa; Martins-Santos, Isabel Cristina

    2015-01-01

    Abstract Fishes of the Loricariidae family, known as “cascudos”, constitute an endemic group in Neotropical freshwaters. In this study, were cytogenetically examined two species of Loricariidae (Pterygoplichthys anisitsi Eigenmann & Kennedy, 1903 and Farlowella amazonum (Günther, 1864) belonging to Hypostominae and Loricariinae subfamilies respectively) from Iguatemi River. Our study provide the first description regarding C-band and fluorochromic analysis in Farlowella amazonum. In Farlowella amazonum, diploid number was 58 chromosomes, with single Ag-NOR and heterochromatic blocks in centromeric regions of some chromosomes and large subtelomeric blocks were evidenced on the long arm of the pair 27, being this region CMA3+/DAPI-. The Pterygoplichthys anisitsi showed diploid number equal 52 chromosomes, with single Ag-NOR and heterochromatic blocks in centromeric and telomeric regions of some chromosomes and conspicuous large telomeric blocks on the long arm of the pair 10, being this region CMA3+/DAPI-. The results show that karyotype formula is nonconservative in Pterygoplichthys anisitsi and Farlowella amazonum. PMID:25893075

  12. Discovering Hidden Diversity of Characins (Teleostei: Characiformes) in Ecuador’s Yasuní National Park

    PubMed Central

    Escobar-Camacho, Daniel; Barriga, Ramiro; Ron, Santiago R.

    2015-01-01

    Background Management and conservation of biodiversity requires adequate species inventories. The Yasuní National Park is one of the most diverse regions on Earth and recent studies of terrestrial vertebrates, based on genetic evidence, have shown high levels of cryptic and undescribed diversity. Few genetic studies have been carried out in freshwater fishes from western Amazonia. Thus, in contrast with terrestrial vertebrates, their content of cryptic diversity remains unknown. In this study, we carried out genetic and morphological analyses on characin fishes at Yasuní National Park, in eastern Ecuador. Our goal was to identify cryptic diversity among one of the most speciose fish families in the Amazon region. This is the first time that genetic evidence has been used to assess the species content of the Napo Basin, one of the richest regions in vertebrate diversity. Results Phylogenetic analyses of partial mitochondrial 16S ribosomal RNA gene (∼600 pb) DNA sequences from 232 specimens of the family Characidae and its closest groups revealed eight candidate new species among 33 species sampled, representing a 24% increase in species number. Analyses of external morphology allowed us to confirm the species status of six of the candidate species. Conclusions Our results show high levels of cryptic diversity in Amazonian characins. If this group is representative of other Amazonian fish, our results would imply that the species richness of the Amazonian ichthyofauna is highly underestimated. Molecular methods are a necessary tool to obtain more realistic inventories of Neotropical freshwater fishes. PMID:26275041

  13. Microsatellite Development for an Endangered Bream Megalobrama pellegrini (Teleostei, Cyprinidae) Using 454 Sequencing

    PubMed Central

    Wang, Jinjin; Yu, Xiaomu; Zhao, Kai; Zhang, Yaoguang; Tong, Jingou; Peng, Zuogang

    2012-01-01

    Megalobrama pellegrini is an endemic fish species found in the upper Yangtze River basin in China. This species has become endangered due to the construction of the Three Gorges Dam and overfishing. However, the available genetic data for this species is limited. Here, we developed 26 polymorphic microsatellite markers from the M. pellegrini genome using next-generation sequencing techniques. A total of 257,497 raw reads were obtained from a quarter-plate run on 454 GS-FLX titanium platforms and 49,811 unique sequences were generated with an average length of 404 bp; 24,522 (49.2%) sequences contained microsatellite repeats. Of the 53 loci screened, 33 were amplified successfully and 26 were polymorphic. The genetic diversity in M. pellegrini was moderate, with an average of 3.08 alleles per locus, and the mean observed and expected heterozygosity were 0.47 and 0.51, respectively. In addition, we tested cross-species amplification for all 33 loci in four additional breams: M. amblycephala, M. skolkovii, M. terminalis, and Sinibrama wui. The cross-species amplification showed a significant high level of transferability (79%97%), which might be due to their dramatically close genetic relationships. The polymorphic microsatellites developed in the current study will not only contribute to further conservation genetic studies and parentage analyses of this endangered species, but also facilitate future work on the other closely related species. PMID:22489139

  14. The complete mitochondrial genome of snubnose pompano Trachinotus blochii (Teleostei, Carangidae).

    PubMed

    Zhang, Dianchang; Wang, Long; Guo, Huayang; Ma, Zhenhua; Jiang, Shigui

    2016-01-01

    The complete mitochondrial genome of Trachinotus blochii was determined using the polymerase chain reaction. The complete mitochondrial DNA sequence is 16,558?bp in length. It consists of 13 protein-coding genes, 22 transfer RNA genes, two rRNA genes and two non-coding regions. Overall base composition of its mitochondrial genome is estimated to be 29.21% for A, 15.74% for G, 26.49% for T, 28.56% for C, respectively, with a high A?+?T content (55.70%). The control region contains three conserved sequence blocks, a termination-associated sequence and a TATA box. The complete mitochondrial genome sequence of T. blochii can provide a basic data for the studies on population structure, molecular systematic, stock evaluation and conservation genetics. It is also helpful to develop the rational management strategies for T. blochii resource. PMID:24893877

  15. Complete mitochondrial genome of the spotted scat Scatophagus argus (Teleostei, Scatophagidae).

    PubMed

    Chen, Jianhua; Li, Yinglei; He, Maoxian; Yan, Binlun; Meng, Xueping

    2015-04-01

    The complete mitochondrial sequence of the spotted scat Scatophagus argus has been determined using long amplification polymerase chain reaction (LA-PCR). The total length of sequence is 16,778 bp, and includes 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 control region. The base composition of H-strand is 27.23% (A), 27.54% (T), 16.22% (G) and 28.81% (C), with an AT content of 55.08%. The arrangement of genes in S. argus is identical to that of other fish species. All genes are encoded on the heavy strand with the exception of ND6 and eight tRNA genes. The mitochondrial genome of S. argus presented here will contribute to resolve phylogenetic relationships within the family Scatophagidae and the Perciformes. PMID:25835066

  16. Glyptothorax igniculus, a new species of sisorid catfish (Teleostei: Siluriformes) from Myanmar.

    PubMed

    Ng, Heok Hee; Kullander, Sven O

    2013-01-01

    Glyptothorax igniculus, new species, is described from the Chindwin River system (part of the Irrawaddy River drainage) in northwestern Myanmar. It differs from other species of Glyptothorax in the Irrawaddy drainage except G. burmanicus in having a thoracic adhesive apparatus with a lanceolate central depression that is nearly enclosed posteriorly by skin ridges, vs. having an adhestive apparatus that is open caudally. In G. burmanicus the adhesive apparatus is oval in outline and completely closed. Glyptothorax chindwinicus Vishwanath & Linthoingambi, 2007 is shown to be a junior synonym of G. burmanicus Prashad & Mukerji, 1929. Glyptothorax rugimentum is reported for the first time from the Chindwin drainage. PMID:25232627

  17. Multilocus resolution of Mugilidae phylogeny (Teleostei: Mugiliformes): Implications for the family's taxonomy.

    PubMed

    Xia, Rong; Durand, Jean-Dominique; Fu, Cuizhang

    2016-03-01

    The interrelationships among mugilids (Mugiliformes: Mugilidae) remain highly debated. Using a mitochondrial gene-based phylogeny as criterion, a revised classification with 25 genera in the Mugilidae has recently been proposed. However, phylogenetic relationships of major mitochondrial lineages remain unresolved and to gain a general acceptance the classification requires confirmation based on multilocus evidence and diagnostic morphological characters. Here, we construct a species-tree using twelve nuclear and three mitochondrial loci and infer the evolution of 71 morphological characters. Our multilocus phylogeny does not agree with previous morphology-based hypotheses for the relationships within Mugilidae, confirms the revised classification with 25 genera and further resolves their phylogenetic relationships. Using the well-resolved multilocus phylogeny as the criterion, we reclassify Mugilidae genera into three new subfamilies (Myxinae, Rhinomugilinae, and Cheloninae) and one new, recombined, subfamily (Mugilinae). The Rhinomugilinae subfamily is further divided into four tribes. The revised classification of Mugilidae is supported by morpho-anatomical synapomorphies or a combination of characters. These characters are used to erect a key to the subfamilies and genera. PMID:26739922

  18. The complete mitochondrial genome of Hoeven's mullet-goby Hemigobius hoevenii (Bleeker) (Teleostei, Gobiidae).

    PubMed

    Huang, Shih-Pin; Shen, Chia-Ning; Chen, I-Shiung

    2016-01-01

    In this study, the complete mitochondrial genome of Hoeven's mullet-goby Hemigobius hoevenii (Bleeker, 1851) collected from Malay Peninsula has been amplified and sequenced. The complete mitochondrial genome is 16,469 base pairs (bp) in total length, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 2 rRNAs, 22 tRNAs, 1 control region (CR) and 1 light-strand replication origin (OL). The overall base composition of H. hoevenii is 27.1% for A, 26.6% for T, 29.0% for C, 17.3% for G, with higher AT content 53.7%. This study will contribute for understanding the phylogenetic approach of Hemigobius species as well as the related genera of gobiid fishes. PMID:24779596

  19. Chriolepis prolata, a new species of Atlantic goby (Teleostei: Gobiidae) from the North American continental shelf.

    PubMed

    Hastings, Philip A; Findley, Lloyd T

    2015-01-01

    A new species of seven-spined goby of the genus Chriolepis is described from five specimens collected from the continental shelf of the northeastern Gulf of Mexico and Atlantic Ocean off South Carolina in depths of ca 54 to 110 m. The "Platform Goby", Chriolepis prolata, is distinguishable from all other western Atlantic species currently assigned to the genus Chriolepis and the morphologically similar genus Varicus in having pelvic-fin rays one through four branched, the fifth (innermost) pelvic-fin ray unbranched and relatively long (longer than the second ray to longer than all other pelvic-fin rays); most lateral body scales ctenoid, extending anteriorly in a wedge to a level anterior to the first dorsal-fin insertion or nearly to the pectoral-fin axil, with two or more rows of small cycloid scales extending anteriorly to near the pectoral-fin axil, cycloid scales along the bases of the dorsal and anal fins, and no scales on the belly; and the first two anal-fin pterygiophores inserted anterior to the first haemal spine. It closely resembles C. bilix but differs from that species which has a scaled belly, a shorter fifth pelvic-fin ray, prolonged dorsal-fin spines and smaller teeth in the lower jaw. An earlier report of C. bilix from Florida waters apparently refers to C. prolata.  PMID:25660803

  20. The complete mitochondrial genome of the Abe's mangrove goby Mugilogobius abei (Teleostei, Gobiidae).

    PubMed

    Huang, Shih-Pin; Shen, Chia-Ning; Chen, I-Shiung

    2015-02-01

    In this study, the complete mitochondrial genome of the Abe's mangrove goby Mugilogobius abei has been amplified. Mugilogobius abei is widely contributed species in Northeast to East Asia. The complete mitogenome is 16,483 base pairs (bp) in total length, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 2 rRNAs, 22 tRNAs, and 1 control region (CR). The overall base composition of M. abei is 27.7% for A, 27.0% for T, 28.6% for C, 16.7% for G, with higher AT content of 54.7%. This study will contribute for understanding the phylogenetic approach in genus Mugilogobius and related gobiid genera. PMID:23901918

  1. Complete mitochondrial genome of the amphidromous, red-tailed goby Sicyopterus lagocephalus (Pallas) (Teleostei, Gobiidae).

    PubMed

    Chiang, Tzen-Yuh; Chen, I-Shiung; Lin, Hung-Du; Hsiao, Sheng-Tai; Ju, Yu-Min

    2015-01-01

    In this article, the complete mitogenome of the amphidromous, red-tailed goby, Sicyopterus lagocephalus has been amplified and sequenced by long polymerase chain reaction. This mitochondrial genome consists of 16,500 bp, with 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a non-coding control region (CR), and its gene arrangement is identical to those of most vertebrates. The CR (841 bp) is located between tRNA(Pro) and tRNA(Phe). The overall base composition of the heavy strand is A, 28.9%; G, 16.4%; C, 28.3%; and T, 26.4%, with a slight AT bias of 55.3%. The complete mitogenomic data may provide more informative for phylogenetic approach for gobioid phylogeny especially for Sicydiine gobies. PMID:24102605

  2. The complete mitochondrial genome of the Java fat-nose goby Pseudogobius javanicus (Teleostei, Gobiidae).

    PubMed

    Huang, Shih-Pin; Shen, Chia-Ning; Chen, I-Shiung

    2015-02-01

    In this study, the complete mitochondrial genome of the fat-nose goby Pseudogobius javanicus has been amplified. P. javanicus is widely contributed species in Southeast to East Asia. The complete mitochondrial genome is 16,493 base pairs (bp) in total length, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 2 rRNAs, 22 tRNAs, 1 control region (CR) and 1 light-strand replication origin (OL). The overall base composition of P. javanicus is 27.1% for A, 27.3% for T, 28.6% for C, 17.0% for G, with higher AT content of 54.4%. This study will contribute for understanding the phylogenetic approach in genus Pseudogobius. PMID:23901921

  3. Prey selection of the shallow water fish Pomatoschistus minutus (Gobiidae, Teleostei) in the SW Baltic

    NASA Astrophysics Data System (ADS)

    Zander, C. Dieter

    1990-06-01

    The aim of this investigation is to demonstrate the reasons of an opportunist feeder to select some components of the available food supply and to avoid others. Object of this test is the eurytopic and euryhaline sand goby, Pomatoschistus minutus (Pallas), from the Luebeck Bight. It inhabits both sand habitats as well as bottoms mixed with pebbles or continuous hard substrates. Therefore, it is often in close contact with Mytilus-belts which present a very rich food supply of small crustaceans. The selectivity behaviour of sand gobies from a sand/clay ecotone was compared with that of populations from a stony pier and a sand bottom during the reproduction period. Regarding the numbers of prey organisms, crustaceans of the periphyton were generally preferred at the pier but avoided in the ecotone. The same is valid for prey organisms of the psammal which were preferred by gobies of the sand bottom but mostly avoided by populations of mixed bottoms. Analyses of size selections revealed that the preferred gammarids or Jaera isopods were between 2 and 5 mm length. A balanced relation of goby biomass and utilizable food supply (predatory impact index) seems to effect positive selectivity of gammarids in the Mytilus-belts or of harpacticoids in the sand bottom.

  4. Two new dwarfgobies of the genus Eviota from the Ryukyu Islands, Japan (Teleostei: Gobiidae).

    PubMed

    Greenfield, David W; Suzuki, Toshiyuki; Shibukawa, Koichi

    2014-01-01

    Two species of dwarfgoby are described from the Ryukyu Islands, Japan. Eviota flebilis n. sp. belongs to cephalic sensory-pore system pattern 2 (lacking only IT pore), has a dorsal/anal fin-ray formula of 8/7, unbranched pectoral-fin rays, the 5th pelvic-fin ray 12.9% of the 4th, a distinctive narrow, red-orange line under the eye, and a dark vertical line at the caudal-fin base. Eviota specca n. sp. has a cephalic sensory-pore system pattern 1 (complete), has a dorsal/anal-fin formula of 8/8, the body heavily sprinkled with chromatophores, and a single dark spot on the upper pectoral-fin base. PMID:24871515

  5. Two new dwarfgobies (Teleostei: Gobiidae) from the Ryukyu Islands, Japan: Eviota flavipinnata and Eviota rubrimaculata.

    PubMed

    Suzuki, Toshiyuki; Greenfield, David W; Motomura, Hiroyuki

    2015-01-01

    Two new species of Eviota from Yoron Island, the Ryukyu Islands, Japan, are described. Both species belong to the cephalic sensory-canal pore system pattern 2 (lacking only the H [IT] pore); have some pectoral-fin rays branched; have a dorsal/anal-fin formula of 9/8; no dark spot over the ural centrum; no prominent distinct dark spots on the pectoral-fin base; no postocular spots; and no strong dark spots on the caudal fin. The species share the most characters with E. afelei, E. bimaculata and E. punctulata, but differ from Eviota afelei and E. punctulata by having two versus three dark marks over the anal-fin base, and from Eviota bimaculata by lacking the two dark, prominent occipital spots present in that species. Both species differ from all other described species of Eviota in fresh coloration. Eviota flavipinnata has bright golden-yellow dorsal fins and an orange anal fin, and a fifth pelvic-fin ray that is 12% the length of the fourth ray. Eviota rubrimaculata has clear dorsal fins with red spots, large red spots on the body, and lacks the fifth pelvic-fin ray. PMID:26623818

  6. Eviota santanai, a new Dwarfgoby from Timor-Leste (Teleostei: Gobiidae).

    PubMed

    Greenfield, David W; Erdmann, Mark V

    2013-01-01

    Eviota santanai is described based on four specimens from Timor-Leste, taken in 5-8 m depth. In general coloration pattern, the species is most similar to E. latifasciata, but differs in the cephalic sensory-pore system pattern, the absence of an occipital spot, and live color including pinkish-mauve bars. Eviota santanai has a dorsal/anal fin-ray formula of 8/8, 5th pelvic-fin ray absent, some lower pectoral-fin rays branched, and IT and PITO pores absent. PMID:25113009

  7. Descriptions of three new species of Glossogobius (Teleostei: Gobiidae) from New Guinea.

    PubMed

    Hoese, Douglass F; Allen, Gerald R

    2015-01-01

    Three new species of Glossogobius are described from New Guinea. Glossogobius multipapillus, n. sp. from northeastern New Guinea has a lobed mental fraenum and a distinctive papilla pattern unlike any other species in the genus. Glossogobius sentaniensis, n. sp. is described from Lake Sentani. The species is similar to Glossogobius aureus and G. koragensis differing in head pores and large dark spots on the body. Glossogobius macrocephalus n. sp. from Lake Tebera and surrounding rivers has a lobed mental fraenum and differs from other species in the Glossogobius celebius group in the combination of having a large head, head pore, fin-ray and predorsal scale counts. PMID:26250181

  8. The Infrabranchial Musculature and Its Bearing on the Phylogeny of Percomorph Fishes (Osteichthyes: Teleostei)

    PubMed Central

    Datovo, Aléssio; de Pinna, Mário C. C.; Johnson, G. David

    2014-01-01

    The muscles serving the ventral portion of the gill arches ( = infrabranchial musculature) are poorly known in bony fishes. A comparative analysis of the infrabranchial muscles in the major percomorph lineages reveals a large amount of phylogenetically-relevant information. Characters derived from this anatomical system are identified and discussed in light of current hypotheses of phylogenetic relationships among percomorphs. New evidence supports a sister-group relationship between the Batrachoidiformes and Lophiiformes and between the Callionymoidei and Gobiesocoidei. Investigated data also corroborate the existence of two monophyletic groups, one including the Pristolepididae, Badidae, and Nandidae, and a second clade consisting of all non-amarsipid stromateiforms. New synapomorphies are proposed for the Atherinomorphae, Blenniiformes, Lophiiformes, Scombroidei (including Sphyraenidae), and Gobiiformes. Within the latter order, the Rhyacichthyidae and Odontobutidae are supported as the successive sister families of all remaining gobiiforms. The present analysis further confirms the validity of infrabranchial musculature characters previously proposed to support the grouping of the Mugiliformes with the Atherinomorphae and the monophyly of the Labriformes with the possible inclusion of the Pholidichthyiformes. Interestingly, most hypotheses of relationships supported by the infrabranchial musculature have been advanced by preceding anatomists on the basis of distinct data sources, but were never recovered in recent molecular phylogenies. These conflicts clearly indicate the current unsatisfactory resolution of the higher-level phylogeny of percomorphs. PMID:25310286

  9. A new species of Didogobius (Teleostei: Gobiidae) from the Canary Islands.

    PubMed

    Van Tassell, James L; Kramer, Annemarie

    2014-01-01

    Didogobius helenae is described from the Canary Islands. It has a sensory papillae pattern that is consistent with the current diagnosis for Didogobius, but lacks all head canals and pores that are present in other members of the genus. Pores, in general, are replaced by large papillae.  The species is defined by first dorsal fin VI; second dorsal fin I,10; anal fin I,9; pectoral fin 16-17; pelvic fin I,5 and disk shaped; lateral scales 28-30, cycloid at anterior, becoming ctenoid posteriorly; cycloid scales present on belly and posterior breast; predorsal region, cheek, operculum and base of pectoral fin without scales; lower most scale on the caudal fin-base with elongate, thickened ctenii along the upper and lower posterior edges. Color in life consists of four mottled, wide brown-orange bars separated by narrower white bars on the trunk, the cheek whitish with 5 more or less circular blotches of orange, outlined in dark brown and a black spot on ventral operculum. A key to the species is provided.  PMID:24870184

  10. Eviota brahmi n. sp. from Papua New Guinea, with a redescription of Eviota nigriventris (Teleostei: Gobiidae).

    PubMed

    Greenfield, David W; Tornabene, Luke

    2014-01-01

    Greenfield & Randall (2011) described the gobiid fishes Eviota dorsogilva from Fiji and E. dorsopurpurea from Papua New Guinea as new species in what they termed the Eviota nigriventris complex. They also extended the range of E. nigriventris, type locality Banda Sea, to Milne Bay, Papua New Guinea. In the present paper, we describe their misidentified E. nigriventris from Papua New Guinea as a new species, E. brahmi, and redescribe E. nigriventris based on new material from near the type locality. The four species of this complex differ mainly in coloration, but are also shown to be distinct using mitochondrial and nuclear DNA. PMID:24870157

  11. The complete mitochondrial genome of the Japanese threadfin bream, Nemipterus japonicus (Teleostei, Nemipteridae).

    PubMed

    Li, Yinglei; Chen, Jianhua; Yan, Binlun; Meng, Xueping

    2016-01-01

    The complete mitochondrial sequence of the Japanese threadfin bream, Nemipterus japonicus has been determined. The circle genome is 16,995?bp in size, and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region. The gene order and composition of N. japonicus was similar to that of most other teleosts. The base composition of H-strand is 28.11% (A), 28.02% (T), 16.64 % (G) and 27.24 % (C), with an AT content of 56.12%. All genes are encoded on the heavy strand with the exception of ND6 and eight tRNA genes. The mitochondrial genome of N. japonicus presented will be in favor of resolving phylogenetic relationships within the family Nemipteridae and the Perciformes. PMID:24660929

  12. Behavioral and neurotoxic effects of arsenic exposure in zebrafish (Danio rerio, Teleostei: Cyprinidae).

    PubMed

    de Castro, Micheli Rosa; Lima, Juliane Ventura; de Freitas, Diana Paula Salomo; Valente, Roberto de Souza; Dummer, Natlia Seus; de Aguiar, Rosiane Borba; dos Santos, Luciane Cougo; Marins, Luis Fernando; Geracitano, Laura Alicia; Monserrat, Jos Mara; Barros, Daniela Mart

    2009-09-01

    This study investigated the passive avoidance conditioning in zebrafish (Danio rerio). An instrument was developed for measuring escape responses triggered by a conditioned stimulus. This system allowed quantification of latency of crossing from a light to a dark zone. Zebrafish were trained to swim from an illuminated to a dark compartment, where they received a body shock (training session). The proposed methodology was efficient for evaluation of working, short, and long-term memory formation of an aquatic animal model. The possibility of employing memory measurements in toxicity tests, in order to obtain an ecologically meaningful biomarker response, was also analyzed. In this experiment, immediately after the training session, fish were exposed to three arsenic (As(V)) concentrations. After the test session, the brain was removed for biochemical analyses. A control group was kept in tap water. After exposure, animals were submitted to a one-trial inhibitory avoidance test for measurement of long-term memory (LTM). Results from behavioral and biochemical analyses showed that the three As(V) concentrations impaired LTM (p<0.05) and increased protein oxidation, which suggests an amnesic and pro-oxidant effect of As(V). Evaluation of behavior parameters in aquatic models is an important complement in studies concerning the environmental impact of chemical substances. PMID:19501674

  13. Parasites in sexual and asexual mollies (Poecilia, Poeciliidae, Teleostei): a case for the Red Queen?

    PubMed Central

    Tobler, Michael; Schlupp, Ingo

    2005-01-01

    The maintenance of sexual reproduction in the face of its supposed costs is a major paradox in evolutionary biology. The Red Queen hypothesis, which states that sex is an adaptation to fast-evolving parasites, is currently one of the most recognized explanations for the ubiquity of sex and predicts that asexual lineages should suffer from a higher parasite load if they coexist with closely related sexuals. We tested this prediction using four populations of the sexual fish species Poecilia latipinna and its asexual relative Poecilia formosa. Contrary to expectation, no differences in parasite load could be detected between the two species. PMID:17148156

  14. Karyotype and chromosome banding of endangered crucian carp, Carassius carassius (Linnaeus, 1758) (Teleostei, Cyprinidae)

    PubMed Central

    Knytl, Martin; Kalous, Luk; Rb, Petr

    2013-01-01

    Abstract The karyotype and other chromosomal characteristics the crucian carp (Carassius carassius (Linnaeus, 1758)) were revealed by means of conventional banding protocols (C, CMA3, AgNOR). The diploid chromosome number (2n) in this species was 100. Its karyotype was composed of 10 pairs of metacentric, 18 pairs of submetacentric and 22 pairs of subtelo- to acrocentric chromosomes without any microchromosomes. C-banding identified blocks of telomeric heterochromatin on seven chromosome pairs. The NORs were situated on the p arms of the 14th pair of submetacentric chromosomes and on the p arms of the 32nd pair of subtelo-acrocentric chromosomes; AgNOR-positive signals corresponded to the CMA3-positive signals. These chromosome characteristics may suggest a paleo-allotetraploid origin of Carassius carassius genome. PMID:24260701

  15. Uncovering the Ancestry of B Chromosomes in Moenkhausia sanctaefilomenae (Teleostei, Characidae)

    PubMed Central

    Utsunomia, Ricardo; Silva, Duílio Mazzoni Zerbinato de Andrade; Ruiz-Ruano, Francisco J.; Araya-Jaime, Cristian; Pansonato-Alves, José Carlos; Scacchetti, Priscilla Cardim; Hashimoto, Diogo Teruo; Oliveira, Claudio; Trifonov, Vladmir A.; Porto-Foresti, Fábio; Camacho, Juan Pedro M.; Foresti, Fausto

    2016-01-01

    B chromosomes constitute a heterogeneous mixture of genomic parasites that are sometimes derived intraspecifically from the standard genome of the host species, but result from interspecific hybridization in other cases. The mode of origin determines the DNA content, with the B chromosomes showing high similarity with the A genome in the first case, but presenting higher similarity with a different species in the second. The characid fish Moenkhausia sanctaefilomenae harbours highly invasive B chromosomes, which are present in all populations analyzed to date in the Parana and Tietê rivers. To investigate the origin of these B chromosomes, we analyzed two natural populations: one carrying B chromosomes and the other lacking them, using a combination of molecular cytogenetic techniques, nucleotide sequence analysis and high-throughput sequencing (Illumina HiSeq2000). Our results showed that i) B chromosomes have not yet reached the Paranapanema River basin; ii) B chromosomes are mitotically unstable; iii) there are two types of B chromosomes, the most frequent of which is lightly C-banded (similar to euchromatin in A chromosomes) (B1), while the other is darkly C-banded (heterochromatin-like) (B2); iv) the two B types contain the same tandem repeat DNA sequences (18S ribosomal DNA, H3 histone genes, MS3 and MS7 satellite DNA), with a higher content of 18S rDNA in the heterochromatic variant; v) all of these repetitive DNAs are present together only in the paracentromeric region of autosome pair no. 6, suggesting that the B chromosomes are derived from this A chromosome; vi) the two B chromosome variants show MS3 sequences that are highly divergent from each other and from the 0B genome, although the B2-derived sequences exhibit higher similarity with the 0B genome (this suggests an independent origin of the two B variants, with the less frequent, B2 type presumably being younger); and vii) the dN/dS ratio for the H3.2 histone gene is almost 4–6 times higher for B chromosomes than for A chromosome sequences, suggesting that purifying selection is relaxed for the DNA sequences located on the B chromosomes, presumably because they are mostly inactive. PMID:26934481

  16. Skin toxins in coral-associated Gobiodon species (Teleostei: Gobiidae) affect predator preference and prey survival

    PubMed Central

    Gratzer, Barbara; Millesi, Eva; Walzl, Manfred; Herler, Juergen

    2015-01-01

    Predation risk is high for the many small coral reef fishes, requiring successful sheltering or other predator defence mechanisms. Coral-dwelling gobies of the genus Gobiodon live in close association with scleractinian corals of the genus Acropora. Earlier studies indicated that the low movement frequency of adult fishes and the development of skin toxins (crinotoxicity) are predation avoidance mechanisms. Although past experiments showed that predators refuse food prepared with goby skin mucus, direct predatorprey interactions have not been studied. The present study compares the toxicity levels of two crinotoxic coral gobies Gobiodon histrio, representative of a conspicuously coloured species, and Gobiodon sp.3 with cryptic coloration using a standard bioassay method. The results show that toxin levels of both species differ significantly shortly after mucus release but become similar over time. Predator preferences were tested experimentally in an aquarium in which the two gobies and a juvenile damselfish Chromis viridis were exposed to the small grouper Epinephelus fasciatus. Video-analysis revealed that although coral gobies are potential prey, E.fasciatus clearly preferred the non-toxic control fish (C.viridis) over Gobiodon. When targeting a goby, the predator did not prefer one species over the other. Contrary to our expectations that toxic gobies are generally avoided, gobies were often captured, but they were expelled quickly, repeatedly and alive. This unusual post-capture avoidance confirms that these gobies have a very good chance of surviving attacks in the field due to their skin toxins. Nonetheless, some gobies were consumed: the coral shelter may therefore also provide additional protection, with toxins protecting them mainly during movement between corals. In summary, chemical deterrence by crinotoxic fishes seems to be far more efficient in predation avoidance than in physical deterrence involving body squamation and/or strong fin spines. PMID:26074654

  17. Isolation and characterization of polymorphic microsatellite loci for the dace complex: Leuciscus leuciscus (Teleostei: Cyprinidae).

    PubMed

    Dubut, Vincent; Martin, Jean-Franois; Gilles, Andr; VAN Houdt, Jeroen; Chappaz, Rmi; Costedoat, Caroline

    2009-07-01

    Ten novel polymorphic microsatellites were isolated from the dace complex (Leuciscus leuciscus), which is a European cyprinid species. Four multiplex polymerase chain reaction sets were optimized in order to genotype 26 polymorphic loci in all, including 16 previously published cyprinid-specific loci. The level of genetic diversity was assessed in 142 dace individuals. We also successfully applied 26 of the microsatellites to 10 related species. These primers thus will be useful to assess population structure of the dace and other cyprinid species, with application for conservation issues and phylogeographical approaches. PMID:21564868

  18. Microsatellite variation and genetic structuring in Mugil liza (Teleostei: Mugilidae) populations from Argentina and Brazil

    NASA Astrophysics Data System (ADS)

    Mai, Ana C. G.; Mio, Carolina I.; Marins, Luis F. F.; Monteiro-Neto, Cassiano; Miranda, Laura; Schwingel, Paulo R.; Lemos, Valria M.; Gonzalez-Castro, Mariano; Castello, Jorge P.; Vieira, Joo P.

    2014-08-01

    The mullet Mugil liza is distributed along the Atlantic coast of South America, from Argentina to Venezuela, and it is heavily exploited in Brazil. We assessed patterns of distribution of neutral nuclear genetic variation in 250 samples from the Brazilian states of Rio de Janeiro, So Paulo, Santa Catarina and Rio Grande do Sul (latitudinal range of 23-31S) and from Buenos Aires Province in Argentina (36S). Nine microsatellite loci revealed 131 total alleles, 3-23 alleles per locus, He: 0.69 and Ho: 0.67. Significant genetic differentiation was observed between Rio de Janeiro samples (23S) and those from all other locations, as indicated by FST, hierarchical analyses of genetic structure, Bayesian cluster analyses and assignment tests. The presence of two different demographic clusters better explains the allelic diversity observed in mullets from the southernmost portion of the Atlantic coast of Brazil and from Argentina. This may be taken into account when designing fisheries management plans involving Brazilian, Uruguayan and Argentinean M. liza populations.

  19. Phylogenetic relationships and natural hybridization in rabbitfishes (Teleostei: Siganidae) inferred from mitochondrial and nuclear DNA analyses.

    PubMed

    Kuriiwa, Kaoru; Hanzawa, Naoto; Yoshino, Tetsuo; Kimura, Seishi; Nishida, Mutsumi

    2007-10-01

    Phylogenetic relationships of rabbitfishes (the family Siganidae), ecologically important components as primary consumers in coral reef communities, were studied using mitochondrial cytochrome b gene and nuclear ITS1 (internal transcribed spacer 1) sequence analyses. The analyses of 19 out of 22 species known in the Western Pacific region revealed that siganids are genetically clustered into three major clades, which are characterized by some morphological and ecological traits. Between closely related species, such as Siganus guttatus-S. lineatus and S. virgatus-S. doliatus, and also between two morphs recognized in S. corallinus, small but discernible genetic differentiation was found, implying that the components of each pair are incipient species. On the other hand, between some species, such as S. fuscescens-S. canaliculatus and S. unimaculatus-S.vulpinus, individuals of the components of each pair were found to construct a genetic mosaic, suggesting that the components are genetic color morphs within a single biological species, respectively. Moreover, evidence from morphological characters, mtDNA, and nuclear DNA gave an inconsistent picture of identity and relationships for several individuals. They were regarded as hybrids or individuals with hybrid origin. Such instances were observed not only between closely related species, such as S. guttatus-S. lineatus, S. virgatus-S. doliatus, and two morphs (incipient species) in S. corallinus, respectively, but also between distantly related ones, such as S. corallinus-S. puellus. In fact, more than half of the species examined (11/20, when treating the two morphs in S. corallinus as independent species) were involved in hybridization. These suggest that hybridization is much more prevalent in marine fishes than previously assumed, and may have some relevance to their diversification. PMID:17590356

  20. Metazoan ectoparasites of Atlantic mackerel, Scomber scombrus (Teleostei: Scombridae): macro- and microhabitat distribution.

    PubMed

    Castro, Ricardo; Santos, Maria João

    2013-10-01

    Parasites are affected by the environment where their hosts live, having a specific distribution among their hosts and occupying a well-defined microhabitat. The present work aims to describe the metazoan ectoparasite fauna of Scomber scombrus, namely its distribution at the macro- and microhabitat levels. For that, fish from two different Portuguese regions, Matosinhos (n = 40) and Figueira da Foz (n = 39), were examined for macroectoparasites. S. scombrus of Matosinhos presented four different parasite species, whilst fish from Figueira da Foz presented five species. All parasites belonged to Monogenea, Copepoda, or Isopoda. The main differences between infection levels of fish from the two localities were found in Grubea cochlear (higher infection levels in Matosinhos) and Caligus pelamydis (where the highest values were found in Figueira da Foz). Regarding the microhabitat of the reported ectoparasites, it could be seen that every species has a very specific distribution within the host: G. cochlear and Kuhnia scombri have a preference for the inner medial areas of gills, Kuhnia sprostonae for the pseudobranchs, and C. pelamydis for the internal wall of opercula. The numerical and functional responses to interspecific competition were absent. These results support the idea that the parasite driving forces of community structure are the reinforcement of reproductive barriers and the enhancement of chances to mate. PMID:23912195

  1. The complete mitochondrial genome of the Zig-zag eel Mastacembelus armatus (Teleostei, Mastacembelidae).

    PubMed

    Li, Qiang; Xu, Ruilin; Shu, Hu; Chen, Qian; Huang, Jianrong

    2016-01-01

    In this paper, the complete mitochondrial DNA (mtDNA) sequence of Mastacembelus armatus was determined. The mitochondrial genome is 16,486?bp in length, including 13 protein-coding genes, 2 ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs) and a noncoding control region as those found in other vertebrates, with the gene identical to that of typical vertebrates. The overall base composition of the heavy strand are 25.28% of A, 29.13% of T, 14.65% of C and 30.93% of G, with a slight AT bias of 54.41%. With the exception of ND6 and eight tRNA genes, all other mitochondrial genes are encoded on the heavy strand. PMID:24617467

  2. Spawning migrations of the endemic Labeobarbus (Cyprinidae, Teleostei) species of Lake Tana, Ethiopia: status and threats.

    PubMed

    Anteneh, W; Getahun, A; Dejen, E; Sibbing, F A; Nagelkerke, L A J; De Graaf, M; Wudneh, T; Vijverberg, J; Palstra, A P

    2012-07-01

    The reproductive biology of the only known intact species flock of large cyprinids, the 16 Labeobarbus species of Lake Tana (Ethiopia), has been extensively studied for the past two decades. Seven species of Labeobarbus are known to migrate >50 km upstream into tributary rivers for spawning during the rainy season (July to October), whereas eight other species are absent from these rivers and probably developed a new strategy of lacustrine spawning (macro-spatial segregation). One species (L. intermedius) probably spawns in the lake as well as in the rivers. Between the early 1990s and 2000s, the riverine spawners showed a decline of 75% in both biomass and number in both fishery independent surveys and in commercial catches. Reproductive migration makes fishes vulnerable to fisheries and other threats like habitat modifications. Lacustrine spawners are probably more resilient as they are not known to form spawning aggregations that can easily be exploited by fishermen. In addition, upstream rivers and catchments around Lake Tana are highly degraded by erosion and recently subjected to intensive habitat modification for irrigation and hydroelectric power generation. This article reviews results of field studies on the Labeobarbus spawning migration from Lake Tana to spawning rivers, giving emphasis on segregation and homing. It also summarizes existing and emerging threats which form potential causes for the decline of the migratory Labeobarbus species. Knowledge gaps on the reproductive biology are identified for further investigation. PMID:22803734

  3. Redescription of Nemachilichthys rueppelli, a senior synonym of N. shimogensis (Teleostei: Nemacheilidae).

    PubMed

    Keskar, Ashwini; Kumkar, Pradeep; Katwate, Unmesh; Ali, Anvar; Raghavan, Rajeev; Dahanukar, Neelesh

    2015-01-01

    The hill-stream loach genus Nemachilichthys, an endemic of the Western Ghats of India, comprises two nominal species, N. rueppelli and N. shimogensis. The validity of the latter has been questioned by several authors. Here we show that there is only a marginal raw mitochondrial genetic distance (0.5% in cytochrome oxidase subunit I and 1.2% in cytochrome b) between topotypic specimens of the two nominal species. Further, although population-level morphometric variations appear in a multivariate morphometric analysis, the two nominal species are morphologically similar, with apparently no significant characters separating them. We therefore consider N. shimogensis to be a junior synonym of N. rueppelli and redescribe the latter, providing further details on population variation and distribution. PMID:26701578

  4. Model-based total evidence phylogeny of Neotropical electric knifefishes (Teleostei, Gymnotiformes).

    PubMed

    Tagliacollo, Victor A; Bernt, Maxwell J; Craig, Jack M; Oliveira, Claudio; Albert, James S

    2016-02-01

    This study provides the most comprehensive Model-Based Total Evidence (MBTE) phylogenetic analyses of the clade Gymnotiformes to date, reappraising relationships using a dataset comprised of six genes (5277bp) and 223 morphological characters, and an ingroup taxon sample including 120 of 212 valid species representing 34 of the 35 extant genera. Our MBTE analyses indicate the two main gymnotiform clades are Gymnotidae and Sternopygoidei, the latter comprised of Rhamphichthyoidea (Rhamphichthyidae+Hypopomidae) and Sinusoidea (Sternopygidae+Apteronotidae). Within Gymnotidae, Electrophorus and Gymnotus are sister taxa, and Gymnotus includes the following six clades: (i) G. pantherinus clade, (ii) G. coatesi clade, (iii) G. anguillaris clade, (iv) G. tigre clade, (v) G. cylindricus clade, and (vi) G. carapo clade. Within Rhamphichthyoidea, Steatogenae (Steatogenys+Hypopygus) is a member of Rhamphichthyidae, and Hypopomidae includes the following clades: (i) Akawaio, (ii) Hypopomus, (iii) Microsternarchini, and (iv) Brachyhypopomus. Within Sternopygidae, Sternopygus and Eigenmanninae are sister groups, Rhabdolichops is the sister to other Eigenmanninae, Archolaemus+Distocyclus is the sister to Eigenmannia, and Japigny is nested within Eigenmannia. Within Apteronotidae, Sternarchorhamphinae (Sternarchorhamphus+Orthosternarchus) is the sister to Apteronotinae, Adontosternarchus is the sister group to other Apteronotinae, Sternarchorhynchini (Sternarchorhynchus+Platyurosternarchus) is the sister to Navajini, and species assigned to Apteronotus are members of two separate clades: (i) A. sensu stricto in the Apteronotini, and (ii) the "A." bonapartii clade in the Navajini. PMID:26616344

  5. Etheostoma erythrozonum, a new species of darter (teleostei: Percidae) from the Meramec River drainage, missouri

    USGS Publications Warehouse

    Switzer, J.F.; Wood, R.M.

    2009-01-01

    A new species of darter, Etheostoma erythrozonum, is described from the Meramec River drainage of Missouri, USA. Etheostoma erythrozonum is the first known fish species endemic to the Meramec River drainage. It differs morphologically and genetically from populations of its sister species, Etheostoma tetrazonum, from the Gasconade River, Osage River, and Moreau River drainages. Copyright ?? 2009 ?? Magnolia Press.

  6. Complete mitochondrial genome of the natural pentaploid loach, Misgurnus anguillicaudatus (Teleostei: Cypriniformes: Cobitididae).

    PubMed

    Zeng, Yu; Chen, Yong-Bo; Pan, Bao-Zhu; Zhang, Da-Wen

    2016-03-01

    The complete mitochondrial genome of the natural pentaploid loach Misgurnus anguillicaudatus is a circular molecule of 16,643 bp in size, containing 13 protein-coding genes, 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes, and two main noncoding regions (the control region and the origin of the light strand replication). Most of the genes are encoded on the heavy strand, except for ND6 and eight tRNAs. The control region is 918 bp in length and located between the tRNA(Pro) and tRNA(Phe) genes, some typical conserved elements (TAS, CSB1-3 and CSB D-F) were found in this region. All these features reflect a typical vertebrate mitochondrial gene arrangement of the pentaploid M. anguillicaudatus. PMID:25162828

  7. Moments of induced spawning and embryonic development of Brycon amazonicus (Teleostei, Characidae).

    PubMed

    Nakaghi, Laura Satiko Okada; Neumann, Erika; Faustino, Francine; Mendes, Jos Mrio Ribeiro; de Braga, Francisco Manoel

    2014-11-01

    Based on the economic and ecological relevance of Brycon amazonicus, the goal of this work was to describe the diameter of oocytes and eggs of this species, as well as the chronological embryonic development. The material was provided by Buriti fish farm, Nova Mutum - MT, Brazil. Samples of both oocytes and eggs were obtained from extrusion to hatching. The material was fixed and measured under stereomicroscope, and the samples were divided for light microscopy or scanning electron microscopy (SEM) analyses. At extrusion, the oocytes were bluish green. The frequency distribution of oocytes revealed that 87.7% of them ranged from 1.11-1.30 mm in diameter. During incubation, the total diameter of the eggs increased from 1.22 0.04 mm to 3.06 0.46 mm in the first 60 min post fertilization (PF), and growth ceased at 180 min PF. Between 10-30 s PF, most eggs were fertilized and fertilization cones were observed from 10 s onwards after gamete activation. The main fertilization events took place asynchronically and spermatozoa were visualized in the micropyle vestibule up to 90 s PF. The first cell was formed in the centre of the blastodisc 20 min PF. The morula stage was identified 2 h PF and, 3 h later, 70% of the yolk was covered by the blastoderm; the blastopore was almost entirely closed at 6 h PF. The cephalic and caudal regions of the embryo could be defined 8 h PF and hatching occurred after 13 h of embryonic development. The larvae hatched with undifferentiated organic systems and with a large yolk sac, free from swimming abilities or visual acuity. PMID:23659693

  8. Retroculus acherontos, a new species of cichlid fish (Teleostei) from the Rio Tocantins basin.

    PubMed

    Landim, Maria Isabel; Moreira, Cristiano R; Figueiredo, Carlos A

    2015-01-01

    Retroculus acherontos is described from the Rio Tocantins basin, Brazil. It is distinguished from all congeners by the presence of a nuchal hump in large specimens, an irregular black blotch located on the middle of the anterior soft dorsal-fin rays, fewer pectoral-fin rays (15-16), a deeper body, a convex ventral profile, a more transversely convex ventral surface of the body, and by chest scales similar in size to the scales on the side. An expanded diagnosis for the genus Retroculus is provided. PMID:26249865

  9. Lake Tanganyika—A 'Melting Pot' of Ancient and Young Cichlid Lineages (Teleostei: Cichlidae)?

    PubMed Central

    Weiss, Juliane D.; Cotterill, Fenton P. D.; Schliewen, Ulrich K.

    2015-01-01

    A long history of research focused on the East Africa cichlid radiations (EAR) revealed discrepancies between mtDNA and nuclear phylogenies, suggesting that interspecific hybridisation may have been significant during the radiation of these fishes. The approximately 250 cichlid species of Lake Tanganyika have their roots in a monophyletic African cichlid assemblage, but controversies remain about the precise phylogenetic origin and placement of different lineages and consequently about L. Tanganyika colonization scenarios. 3312 AFLP loci and the mitochondrial ND2 gene were genotyped for 91 species representing almost all major lacustrine and riverine haplotilapiine east African cichlid lineages with a focus on L. Tanganyika endemics. Explicitly testing for the possibility of ancient hybridisation events, a comprehensive phylogenetic network hypothesis is proposed for the origin and diversification of L. Tanganyika cichlids. Inference of discordant phylogenetic signal strongly suggests that the genomes of two endemic L. Tanganyika tribes, Eretmodini and Tropheini, are composed of an ancient mixture of riverine and lacustrine lineages. For the first time a strong monophyly signal of all non-haplochromine mouthbrooding species endemic to L. Tanganyika (“ancient mouthbrooders”) was detected. Further, in the genomes of early diverging L. Tanganyika endemics Trematocarini, Bathybatini, Hemibatini and Boulengerochromis genetic components of other lineages belonging to the East African Radiation appear to be present. In combination with recent palaeo-geological results showing that tectonic activity in the L. Tanganyika region resulted in highly dynamic and heterogeneous landscape evolution over the Neogene and Pleistocene, the novel phylogenetic data render a single lacustrine basin as the geographical cradle of the endemic L. Tanganyika cichlid lineages unlikely. Instead a scenario of a pre-rift origin of several independent L. Tanganyika precursor lineages which diversified in ancient rivers and precursor lakes and then amalgamated in the extant L. Tanganyika basin is put forward as an alternative: the 'melting pot Tanganyika' hypothesis. PMID:25928886

  10. Molecular Evidence for Multiple Origins of the European Spined Loaches (Teleostei, Cobitidae)

    PubMed Central

    Perdices, Anabel; Bohlen, Joerg; Šlechtová, Vendula; Doadrio, Ignacio

    2016-01-01

    We present a phylogenetic investigation of the Northern Clade, the major monophyletic clade within the freshwater fish family Cobitidae, one of the most prominent families of freshwater fishes found in Asian and European waters. Phylogenetic reconstructions based on the cytochrome b and RAG-1 genes show the genera Microcobitis, Sabanejewia, Koreocobitis and Kichulchoia as monophyletic groups. These reconstructions also show a Cobitis sensu lato and a Misgurnus sensu lato group. The Cobitis sensu lato group includes all species of Cobitis, Iksookimia, Niwaella and Kichulchoia, while the Misgurnus sensu lato group includes Misgurnus, Paramisgurnus and Koreocobitis. Although the monophyly of both the Cobitis sensu lato and Misgurnus sensu lato groups is supported, relationships within the groups are incongruent with current generic definitions. The absence of monophyly of most genera included in the Cobitis sensu lato group (Cobitis, Iksookimia and Niwaella) or their low genetic differentiation (Kichuchoia) supports their consideration as synonyms of Cobitis. Molecular phylogenies indicate that the Asian species of Misgurnus experienced a mitochondrial introgression from a lineage of Cobitis. We also find two nuclear haplotypes in the same Cobitis species from the Adriatic area that, in the absence of morphological differentiation, may indicate molecular introgression. Most lineages within the Northern Clade consist of species found in East Asia. However, some lineages also contain species from Europe and Asia Minor. The phylogenetic relationships presented here are consistent with previous studies suggesting an East Asian origin of the Northern Clade. According to the current distributions and phylogenetic relationships of the Misgurnus sensu lato and Cobitis clade lineages, particularly of M. fossilis and C. melanoleuca, the range expansion of East Asian species into Europe was most likely via Siberia into Northern and Central Europe. Phylogenetic analyses also show that the Cobitis sensu lato group consists of two clear subgroups (I and II), each presenting geographical differences. Subgroup I is distributed exclusively in East Asian drainages with an Eastern European offshoot (C. melanoleuca), whereas Subgroup II includes species widespread throughout Europe (including the Mediterranean), Asia Minor, the Black Sea and the Caucasus, with some lineages related to species restricted to East Asia. PMID:26727121

  11. Callionymus omanensis, a new species of dragonet from Oman, north-western Indian Ocean (Teleostei: Callionymidae).

    PubMed

    Fricke, R; Jawad, L A; Al-Mamry, J M

    2014-11-01

    A new species of deep-living dragonet Callionymus omanensis from Oman is described on the basis of a single male specimen collected in a trawl from 500 m depth off the coast of Oman. The new species is characterized within the subgenus Bathycallionymus by having a small branchial opening; head short (3·9 in proportion to standard length); eye large (2·4 in proportion to head length); preopercular spine with a long, upcurved main tip, with a small antrorse barb and a larger antrorse spine, and with a strong antrorse spine laterally at the preopercular-spine base, ventral margin smooth; first dorsal fin slightly higher than second dorsal fin (male); second dorsal fin distally straight; 17 pectoral fin rays; distal end of caudal fin slightly pointed, with two median unbranched rays bearing short filaments; first dorsal fin with basal black spot reaching from first to fourth membranes, third membrane with an ocellated distal black blotch; second dorsal fin with vertical dark grey bars; distal three-fourths of anal fin black; upper half of caudal fin with oblique dark grey bars; pelvic fin dark grey, second ray basally with a black blotch. The new species is compared with similar species. Revised keys to callionymid species of the western Indian Ocean and the Red Sea, as well as species of the subgenus Bathycallionymus, are presented. PMID:25098471

  12. Whole chromosome painting of B chromosomes of the red-eye tetra Moenkhausia sanctaefilomenae (Teleostei, Characidae).

    PubMed

    Scudeler, Patricia Elda Sobrinho; Diniz, Débora; Wasko, Adriane Pinto; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    B chromosomes are dispensable genomic elements found in different groups of animals and plants. In the present study, a whole chromosome probe was generated from a specific heterochromatic B chromosome occurring in cells of the characidae fish Moenkhausia sanctaefilomenae (Steindachner, 1907). The chromosome painting probes were used in fluorescence in situ hybridization (FISH) experiments for the assessment of metaphase chromosomes obtained from individuals from three populations of Moenkhausia sanctaefilomenae. The results revealed that DNA sequences were shared between a specific B chromosome and many chromosomes of the A complement in all populations analyzed, suggesting a possible intra-specific origin of these B chromosomes. However, no hybridization signals were observed in other B chromosomes found in the same individuals, implying a possible independent origin of B chromosome variants in this species. FISH experiments using 18S rDNA probes revealed the presence of non-active ribosomal genes in some B chromosomes and in some chromosomes of the A complement, suggesting that at least two types of B chromosomes had an independent origin. The role of heterochromatic segments and ribosomal sequences in the origin of B chromosomes were discussed. PMID:26753081

  13. Comparative analysis of sex chromosomes in Leporinus species (Teleostei, Characiformes) using chromosome painting

    PubMed Central

    2013-01-01

    Background The Leporinus genus, belonging to the Anostomidae family, is an interesting model for studies of sex chromosome evolution in fish, particularly because of the presence of heteromorphic sex chromosomes only in some species of the genus. In this study we used W chromosome-derived probes in a series of cross species chromosome painting experiments to try to understand events of sex chromosome evolution in this family. Results W chromosome painting probes from Leporinus elongatus, L. macrocephalus and L. obtusidens were hybridized to each others chromosomes. The results showed signals along their W chromosomes and the use of L. elongatus W probe against L. macrocephalus and L. obtusidens also showed signals over the Z chromosome. No signals were observed when the later aforementioned probe was used in hybridization procedures against other four Anostomidae species without sex chromosomes. Conclusions Our results demonstrate a common origin of sex chromosomes in L. elongatus, L. macrocephalus and L. obtusidens but suggest that the L. elongatus chromosome system is at a different evolutionary stage. The absence of signals in the species without differentiated sex chromosomes does not exclude the possibility of cryptic sex chromosomes, but they must contain other Leporinus W sequences than those described here. PMID:23822802

  14. Paleoclimatic history and vicariant speciation in the "sand goby" group (Gobiidae, Teleostei).

    PubMed

    Huyse, Tine; Houdt, Jeroen Van; Volckaert, Filip A M

    2004-07-01

    Vicariant and climatic cycling speciation hypotheses of the 'sand gobies' belonging to the genera Pomatoschistus, Gobiusculus, Knipowitschia, and Economidichthys are tested using molecular phylogenies constructed of nuclear DNA (ITS1 locus) and mitochondrial DNA (12S and 16S fragments). These gobies are among the most abundant in the Eastern Atlantic-Mediterranean region, and play an important role in the ecosystem. Considerable ITS1 length differences, primarily due to the presence of several tandem repeats, were found between species and even within individuals. Therefore, phylogenetic analyses focused on fragments of the 12S and 16S mtDNA region that have been sequenced for 16 goby taxa. The 'sand gobies' clustered as a monophyletic group as proposed on morphological grounds. However, G. flavescens, E. pygmaeus, and K. punctatissima clustered within the Pomatoschistus species, pointing to a paraphyletic origin of these genera. Furthermore, the genetic divergence between P. minutus from the Adriatic Sea versus the Atlantic-Mediterranean region was as high as the divergence within the P. minutus complex, suggesting that P. minutus from the Adriatic Sea should be considered as a distinct species. The "star" phylogeny might suggest that these gobies evolved in a very short time period, possibly linked to the drastic alterations in the Mediterranean Sea during and immediately after the Messinian salinity crisis at the end of the Miocene. The freshwater life-style appeared monophyletic; equating its origin with the salinity crisis resulted in a molecular clock estimate of 1.4% divergence per million years. The last common ancestor probably occupied sandy bottoms and a coastal niche while several species subsequently adapted to new habitats (pelagic, freshwater or stenohaline). The origin of the shallowest clades dated back to the glacial cycling during the Pleistocene epoch. PMID:15186817

  15. Eviota nigramembrana, a new dwarfgoby from the Western Pacific (Teleostei: Gobiidae).

    PubMed

    Greenfield, David W; Suzuki, Toshiyuki

    2013-01-01

    Eviota nigramembrana is described from the Ryukyu Islands, Japan and also recorded from the Philippine Islands. It belongs to the cephalic sensory-pore system pattern group I (complete), has a dorsal/anal fin-ray formula of 8/8, 5th pelvic-fin ray absent, some lower pectoral-fin rays branched, five dark internal bands between anal-fin origin and caudal fin, no distinct marking on pectoral-fin base, dark internal rectangular mark above midline of ural centrum, a light spinous dorsal fin, and black pigment on the opercular membrane. PMID:26046191

  16. Tracking the elusive monophyly of nototheniid fishes (Teleostei) with multiple mitochondrial and nuclear markers.

    PubMed

    Dettai, A; Berkani, M; Lautredou, A-C; Couloux, A; Lecointre, G; Ozouf-Costaz, C; Gallut, C

    2012-12-01

    Since the first molecular study of the suborder Notothenioidei in 1994, many phylogenetic studies have been published. Among these, those with a sufficient number of taxa have all suggested that the Nototheniidae, as currently defined, is monophyletic only with the inclusion of the Channichthyidae, Artedidraconidae, Bathydraconidae and Harpagiferidae. This is corroborated by more recent studies including more taxa, but in these studies either the number of nuclear markers or the number of taxa included remained low. We obtained sequences for a large sampling covering most nototheniid genera for five markers described previously for other samplings (COI, Rhodopsin retrogene, Pkd1, HECW2, and SSRP1) and one nuclear marker never used before in phylogenetic inference (PPM1d). The topology for the combined analysis of the nuclear coding genes, as well as the topology for SSRP1 (non-coding) and the combined analysis for all markers all support the paraphyly of Nototheniidae, the genus Notothenia (including Paranotothenia) is the sister group of the clade Channichthyidae, Artedidraconidae, Bathydraconidae and Harpagiferidae, and genus Gobionotothen is a sister group to both. As in previous studies, Trematomus, Lepidonotothen and Patagonotothen form a clade that also includes Indonotothenia cyanobrancha. The position of Pleuragramma antarctica, Dissostichus species and Aethotaxis mitopteryx remains unstable and dependant on markers and analyses. We therefore propose the inclusion of the four families of the High Antarctic clade in the Nototheniidae, and their transformation into subfamilies. We transfer Paranotothenia magellanica to the genus Notothenia, as Notothenia magellanica. PMID:23199880

  17. Infection of the heart of Pimelodus ornatus (Teleostei, Pimelodidae), by Myxobolus sp. (Myxozoa, Myxobolidae).

    PubMed

    Matos, Edilson; Videira, Marcela; Velasco, Michele; Sanches, Osimar; Clemente, Sergio Carmona de So; Matos, Patricia

    2014-01-01

    The phylum Myxozoa Grass, 1970, consists of a heterogenous group of around 50 genera that are worldwide disseminated in a wide variety of aquatic media. In the present study, 43 specimens of Pimelodus ornatus were collected from an adjacent area to the Cachoeira do Arari municipality on Maraj Island, in the Brazilian state of Par, in 2013. Macroscopic analysis showed the presence of whitened plasmodia located in the cardiac muscle and also in the region between the bulbus arteriosus and atrium cordis. Microscopic analysis on the parasitized tissues revealed spores that were typically piriform, with the anterior portion slightly narrower than the posterior end. The spore valves were symmetrical. The present species is placed in the genus Myxobolus Butschli, 1882, because of the presence of a pair of equal polar capsules in each spore. The prevalence of parasitism observed was 13.9% (6/43). This research note reports the first occurrence of Myxobolus as a parasite of the heart in the teleostean fish P. ornatus in the Amazon region and confirms the occurrence of secondary myocarditis in this fish, caused by parasitism by Myxobolus sp. The rarity of this parasitic species of Myxobolus at this tissue site, associated with other spore morphology characteristics in the fish, suggests that it is an undescribed species. PMID:25517538

  18. The structure and ultrastructure of the rostral cartilage in the spiny eel, Macrognathus siamensis (Teleostei: Mastacembeloidei).

    PubMed Central

    Benjamin, M; Sandhu, J S

    1990-01-01

    An elastic, cell-rich cartilage provides flexible support to the highly mobile, rostral tentacle of the mastacembelid, Macrognathus siamensis. Active movement of the tentacle is effected by skeletal muscles, the muscular bellies of which are located outside the organ. The tentacle returns to its original shape by elastic recoil. The cartilage resembles plant supporting tissue and the cartilages of certain invertebrates. It is surrounded by a thick perichondrium and articulates at a synovial joint with the supraethmoid. The chondrocytes are large and shrunken within lacunae. They contain glycogen and cytoplasmic stores of RNA. The matrix is reduced to thin seams between adjacent cells, and stains strongly with alcian blue and a variety of elastic stains. Parts of the matrix are trilaminar, and such an appearance recalls the distinction between the primary cell walls of adjacent plant cells and the intervening middle lamella. The perichondrium consists of an alternating sequence of cells, circularly arranged collagen fibres and a foamy, amorphous material of unknown composition. Deep to the perichondrium, the chondrocytes are packed with intermediate filaments. Membrane-bound organelles are not prominent, though mitochondria are located at the periphery of the cell. The ultrastructural similarities between these chondrocytes and those of hyaline-cell cartilage (chondroid) support the contention that Schaffer's concept of a rigid distinction between 'true' cartilage and 'chondroid' is no longer tenable. The matrix is devoid of collagen and is most distinctive. In the immediate vicinity of the cells it consists of matrix granules and matrix fibers but, where a trilaminar appearance is easily discernible, there is a central zone that consists of large masses of amorphous material that is presumed to contain elastin. Such amorphous material has not previously been seen in any teleostean elastic tissue. By contrast, elastic system fibres, readily demonstrable elsewhere in teleosts, are conspicuously absent. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 PMID:1696572

  19. Pethia rutila (Teleostei: Cyprinidae), a new species from Mizoram, Northeast India.

    PubMed

    Lalramliana, Lalramliana; Knight, J D Marcus; Laltlanhlua, Zathang

    2014-01-01

    Pethia rutila, a new species is described from Karnaphuli drainage, Mizoram, Northeast India. It is distinguished from its congeners in having a complete lateral line with 21-22 scales, an inconspicuous black humeral spot on the scale row below the 3rd and 4th lateral-line scales, a black blotch on the caudal peduncle centered above the insertion of the last anal-fin ray, overlapping lateral-line scales 16-18 or 17-19 and 4/1/3 scales in transverse line from dorsal-fin origin to pelvic-fin origin. PMID:25081166

  20. A review of the species of Oreichthys (Teleostei: Cyprinidae) in the Western Ghats, India.

    PubMed

    Knight, J D Marcus; Kumar, Rahul G

    2015-01-01

    Fishes currently assigned to Oreichthys cosuatis from the Western Ghats are shown to belong to a closely-related group of three valid species: Puntius coorgensis, which is raised from synonymy, and two new species, O. duospilus and O. incognito. Oreichthys coorgensis can be distinguished from its congeners by a combination of characters that include 22-23+1-2 scales in the longitudinal series with 5-8 pored scales; 3/1/2 scales in the transverse row; 6-7 predorsal scales and usually a faint blackish spot on the caudal-fin base. Oreichthys duospilus, sp. nov., can be distinguished by possessing an almost complete lateral line with 11-21 pored scales and two black spots: one on the dorsal fin and the other on the anal fin. Oreichthys incognito, sp. nov., can be distinguished by a lateral line with 5 pored scales; 3/1/1 scales in the transverse row; 8 predorsal scales and a vertical black bar on the dorsal fin. PMID:25661937

  1. The gulf surgeon, Acanthurus randalli, a junior synonym of the ocean surgeon, Acanthurus bahianus (teleostei: Acanthuridae)

    USGS Publications Warehouse

    Smith-Vaniz, W.F.; Jelks, H.L.; Randall, J.E.

    2003-01-01

    We compared 62 specimens, 48-126.5 mm standard length, of Acanthurus bahianus from the northeastern Gulf of Mexico with 95 specimens from other localities to determine if the distinguishing characters in the original description of the Gulf of Mexico endemic surgeonfish Acanthurus randalli were valid. No color pattern or meristic differences were found, and the only measurement that allowed distinction (91% percent concordance) was the shallower caudal concavity of northeastern Gulf of Mexico specimens. Acanthurus chirurgus from the northeastern Gulf of Mexico also have shallower caudal concavities (93.7% percent concordance) than do conspecifics from other areas, suggesting that this trend may be correlated with some unknown environmental influence. Considering the extended planktonic larval dispersal capabilities of Atlantic surgeonfishes, and that the single divergent morphological character state is also exhibited in a sympatric northeastern Gulf of Mexico population of A. chirurgus, recognition of A. randalli is untenable, and the name is considered a junior synonym of A. bahianus. An identification key to western Atlantic species of Acanthurus that incorporates the results of this study is given.

  2. Morphological variation of the palatal organ and chewing pad of catostomidae (teleostei: cypriniformes).

    PubMed

    Doosey, Michael H; Bart, Henry L

    2011-09-01

    We studied the morphology and shape variation of the palatal organ and chewing pad of sucker fishes, family Catostomidae. The palatal organ is a muscularized structure that forms a large mass on the roof of the posterior part of the buccopharyngeal cavity in cypriniform fishes. It functions in coordination with the branchial arches to separate food items from inorganic debris during feeding. The palatal organ exhibits considerable variability in morphology among catostomids. It is shorter, narrower, and thinner in species of the subfamily Cycleptinae (e.g., Cycleptus elongatus) than in other catostomid subfamilies. The thickest and widest palatal organ is seen in species of the subfamily Ictiobinae (e.g., Ictiobus cyprinellus). The shape and size of the palatal organ generally varies between these extremes in species of subfamily Catostominae (e.g., Catostomus and Moxostoma species). Principal components analysis and analysis of variance has differentiated means of various palatal organ measurements for each monophyletic subfamily and tribe of Catostomidae with statistical significance. These results corroborate previously established typological classification of catostomids based on pharyngeal tooth count, pharyngeal tooth morphology, and diet. A keratinized chewing pad forms on the posterior surface of the palatal organ in catostomids or on a skeletal process in cyprinids and serves as an occlusion surface for pharyngeal teeth. The chewing pad is lunate in catostomids and generally ovoid in cyprinids. It is absent from the species of loaches (e.g., botiids, cobitids, and nemacheilids) and gyrinocheilids examined. A synonymy of terms used in the past to describe the palatal organ and chewing pad of Cypriniformes is provided. PMID:21598291

  3. Badis britzi, a new percomorph fish (Teleostei: Badidae) from the Western Ghats of India.

    PubMed

    Dahanukar, Neelesh; Kumkar, Pradeep; Katwate, Unmesh; Raghavan, Rajeev

    2015-01-01

    Badis britzi, the first species of the genus endemic to southern India, is described from the Nagodi tributary of the west-flowing Sharavati River in Karnataka. It is distinguished from congeners by a combination of characters including a slender body, 21-24 pored lateral-line scales and a striking colour pattern consisting of 11 bars and a mosaic of black and red pigmentation on the side of the body including the end of caudal peduncle, and the absence of cleithral, opercular, or caudal-peduncle blotches, or an ocellus on the caudal-fin base. Badis triocellus Khynriam & Sen is considered a junior synonym of B. singenensis Geetakumari & Kadu. PMID:25947522

  4. Embryonic fissure and photoreceptor differentiation in the eye of adult Garra rufa Heckel 1843 (Cyprinidae, Teleostei).

    PubMed

    al-Adhami, M A; Qar, J; al Khodur, M

    2001-01-01

    The retina of the adult teleost Garra rufa retains a curved, open embryonic fissure indicating an asymmetrical postembryonic retinal growth. Undifferentiated, oval photoreceptors are observed on both sides of the middle of the fissure with their larger diameter running parallel to the fissure to which they may attach by desmosomes. They detach from the fissure, rotate to become perpendicular to it and begin an active process of differentiation as they slide along the temporal side of the outer half of the fissure. This process is divided into stages for simplicity. The photoreceptors develop stumpy inner segments extending into a ventricular space that appears between the retinal pigment epithelium and the photoreceptors. Calycal processes arise from the inner segments and the distal centriole of each photoreceptor forms a connecting cilium. The proximal centriole is retained for some time after the outer segment develops. The formation of rod spherules and cone pedicles takes place almost concomitantly with the outer segments. Double cones appear first as single cones before pairing. One or more of the principal cone mitochondria accumulate electron-dense material and merge to form the ellipsosome. The retinal pigment epithelium undergoes a parallel differentiation. The developmental events described in the present work conform those recorded in embryonic teleostean retinas. PMID:11987455

  5. Genetic population structure of sympatric and allopatric populations of Baltic ciscoes (Coregonus albula complex, Teleostei, Coregonidae)

    PubMed Central

    2010-01-01

    Background Teleost fishes of the Coregonidae are good model systems for studying postglacial evolution, adaptive radiation and ecological speciation. Of particular interest is whether the repeated occurrence of sympatric species pairs results from in-situ divergence from a single lineage or from multiple invasions of one or more different lineages. Here, we analysed the genetic structure of Baltic ciscoes (Coregonus albula complex), examining 271 individuals from 8 lakes in northern Germany using 1244 polymorphic AFLP loci. Six lakes had only one population of C. albula while the remaining two lakes had C. albula as well as a sympatric species (C. lucinensis or C. fontanae). Results AFLP demonstrated a significant population structure (Bayesian ?B = 0.22). Lower differentiation between allopatric (?B = 0.028) than sympatric (0.063-0.083) populations contradicts the hypothesis of a sympatric origin of taxa, and there was little evidence for stocking or ongoing hybridization. Genome scans found only three loci that appeared to be under selection in both sympatric population pairs, suggesting a low probability of similar mechanisms of ecological segregation. However, removal of all non-neutral loci decreased the genetic distance between sympatric pairs, suggesting recent adaptive divergence at a few loci. Sympatric pairs in the two lakes were genetically distinct from the six other C. albula populations, suggesting introgression from another lineage may have influenced these two lakes. This was supported by an analysis of isolation-by-distance, where the drift-gene flow equilibrium observed among allopatric populations was disrupted when the sympatric pairs were included. Conclusions While the population genetic data alone can not unambiguously uncover the mode of speciation, our data indicate that multiple lineages may be responsible for the complex patterns typically observed in Coregonus. Relative differences within and among lakes raises the possibility that multiple lineages may be present in northern Germany, thus understanding the postglacial evolution and speciation in the C. albula complex requires a large-scale phylogenetic analysis of several potential founder lineages. PMID:20350300

  6. Molecular Evidence for Multiple Origins of the European Spined Loaches (Teleostei, Cobitidae).

    PubMed

    Perdices, Anabel; Bohlen, Joerg; lechtov, Vendula; Doadrio, Ignacio

    2016-01-01

    We present a phylogenetic investigation of the Northern Clade, the major monophyletic clade within the freshwater fish family Cobitidae, one of the most prominent families of freshwater fishes found in Asian and European waters. Phylogenetic reconstructions based on the cytochrome b and RAG-1 genes show the genera Microcobitis, Sabanejewia, Koreocobitis and Kichulchoia as monophyletic groups. These reconstructions also show a Cobitis sensu lato and a Misgurnus sensu lato group. The Cobitis sensu lato group includes all species of Cobitis, Iksookimia, Niwaella and Kichulchoia, while the Misgurnus sensu lato group includes Misgurnus, Paramisgurnus and Koreocobitis. Although the monophyly of both the Cobitis sensu lato and Misgurnus sensu lato groups is supported, relationships within the groups are incongruent with current generic definitions. The absence of monophyly of most genera included in the Cobitis sensu lato group (Cobitis, Iksookimia and Niwaella) or their low genetic differentiation (Kichuchoia) supports their consideration as synonyms of Cobitis. Molecular phylogenies indicate that the Asian species of Misgurnus experienced a mitochondrial introgression from a lineage of Cobitis. We also find two nuclear haplotypes in the same Cobitis species from the Adriatic area that, in the absence of morphological differentiation, may indicate molecular introgression. Most lineages within the Northern Clade consist of species found in East Asia. However, some lineages also contain species from Europe and Asia Minor. The phylogenetic relationships presented here are consistent with previous studies suggesting an East Asian origin of the Northern Clade. According to the current distributions and phylogenetic relationships of the Misgurnus sensu lato and Cobitis clade lineages, particularly of M. fossilis and C. melanoleuca, the range expansion of East Asian species into Europe was most likely via Siberia into Northern and Central Europe. Phylogenetic analyses also show that the Cobitis sensu lato group consists of two clear subgroups (I and II), each presenting geographical differences. Subgroup I is distributed exclusively in East Asian drainages with an Eastern European offshoot (C. melanoleuca), whereas Subgroup II includes species widespread throughout Europe (including the Mediterranean), Asia Minor, the Black Sea and the Caucasus, with some lineages related to species restricted to East Asia. PMID:26727121

  7. A new species of Pseudophoxinus (Teleostei: Cyprinidae) from Southwestern Anatolia, Turkey.

    PubMed

    Ekmeki, F Gler; Atalay, M Altu?; Yo?urtuo?lu, Baran; Turan, Davut; Kk, Fahrettin

    2015-01-01

    Pseudophoxinus mehmeti, new cyprinid species from the Alanky basin in south-western Turkey, is distinguished from all species of Pseudophoxinus in adjacent regions by the combination of the following characters: body slender, its length 1.3-1.5 times its depth; caudal peduncle length 1.6-2.0 times its depth; mouth almost superior, with the tip of the mouth-cleft approximately level with the middle of the pupil; snout with a pointed tip, its length markedly greater than eye diameter; lateral line not complete, with 30-50 perforated scales and 48-60+2 scale rows in lateral series; 11-13 scale rows between lateral line and dorsal-fin origin, 3-5 scale rows between lateral line and anal-fin origin; dorsal-fin with 6-7 branched rays; anal-fin with 6-7 branched rays; a distinct black epidermal stripe from eye to caudal-fin base in preserved individuals. PMID:26624395

  8. Shape based assignment tests suggest transgressive phenotypes in natural sculpin hybrids (Teleostei, Scorpaeniformes, Cottidae)

    PubMed Central

    Nolte, Arne W; Sheets, H David

    2005-01-01

    Background Hybridization receives attention because of the potential role that it may play in generating evolutionary novelty. An explanation for the emergence of novel phenotypes is given by transgressive segregation, which, if frequent, would imply an important evolutionary role for hybridization. This process is still rarely studied in natural populations as samples of recent hybrids and their parental populations are needed. Further, the detection of transgressive segregation requires phenotypes that can be easily quantified and analysed. We analyse variability in body shape of divergent populations of European sculpins (Cottus gobio complex) as well as natural hybrids among them. Results A distance-based method is developed to assign unknown specimens to known groups based on morphometric data. Apparently, body shape represents a highly informative set of characters that parallels the discriminatory power of microsatellite markers in our study system. Populations of sculpins are distinct and "unknown" specimens can be correctly assigned to their source population based on body shape. Recent hybrids are intermediate along the axes separating their parental groups but display additional differentiation that is unique and coupled with the hybrid genetic background. Conclusion There is a specific hybrid shape component in natural sculpin hybrids that can be best explained by transgressive segregation. This inference of how hybrids differ from their ancestors provides basic information for future evolutionary studies. Furthermore, our approach may serve to assign candidate specimens to their source populations based on morphometric data and help in the interpretation of population differentiation. PMID:15987531

  9. Molecular phylogeny and evolution of Scomber (Teleostei: Scombridae) based on mitochondrial and nuclear DNA sequences

    NASA Astrophysics Data System (ADS)

    Cheng, Jiao; Gao, Tianxiang; Miao, Zhenqing; Yanagimoto, Takashi

    2011-03-01

    A molecular phylogenetic analysis of the genus Scomber was conducted based on mitochondrial (COI, Cyt b and control region) and nuclear (5S rDNA) DNA sequence data in multigene perspective. A variety of phylogenetic analytic methods were used to clarify the current taxonomic Classification and to assess phylogenetic relationships and the evolutionary history of this genus. The present study produced a well-resolved phylogeny that strongly supported the monophyly of Scomber. We confirmed that S. japonicus and S. colias were genetically distinct. Although morphologically and ecologically similar to S. colias, the molecular data showed that S. japonicus has a greater molecular affinity with S. australasicus, which conflicts with the traditional taxonomy. This phylogenetic pattern was corroborated by the mtDNA data, but incompletely by the nuclear DNA data. Phylogenetic concordance between the mitochondrial and nuclear DNA regions for the basal nodes Supports an Atlantic origin for Scomber. The present-day geographic ranges of the species were compared with the resultant molecular phylogeny derived from partition Bayesian analyses of the combined data sets to evaluate possible dispersal routes of the genus. The present-day geographic distribution of Scomber species might be best ascribed to multiple dispersal events. In addition, our results suggest that phylogenies derived from multiple genes and long sequences exhibited improved phylogenetic resolution, from which we conclude that the phylogenetic reconstruction is a reliable representation of the evolutionary history of Scomber.

  10. Mitochondrial genome of the sucking disc gudgeon, Discogobio yunnanensis (Teleostei, Cypriniformes).

    PubMed

    Xue, Yang; Chen, Hui-Juan; Li, Yang; Tang, Min; Chen, Hong-Jun; Ye, Qin; Li, Yun

    2016-03-01

    The complete mitochondrial genome of Discogobio yunnanensis was determined using the polymerase chain reaction and directly sequenced with the primer walking method. The whole mitogenome was 16,602?bp in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and 1 control region. It had the typical circular molecule structure of vertebrate's mitogenome. The whole base composition was estimated to be 32.10% A, 26.79% T, 25.95% C, 15.16% G with AT bias of 58.89%. The complete mitogenome of D. yunnanensis provides the fundamental data for conservation genetics study on this freshwater fish species. PMID:25162381

  11. Complete mitochondrial genome of the Chinese balitorine loach, Metahomaloptera omeiensis (Teleostei, Cypriniformes).

    PubMed

    Li, Yang; Tang, Min; Xue, Yang; Chen, Hui-Juan; Ye, Qin; Li, Yun

    2016-03-01

    The Metahomaloptera omeiensis is the only one species within the genus, Metahomaloptera. The complete mitochondrial genome of M. omeiensis was sequenced, which was 16,558?bp in length, including 13 protein-coding genes, 7 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and 1 control region. It has the typical circular molecule structure of vertebrate's mitochondrial genome. The whole base composition was estimated to be 29.44% A, 25.44% T, 28.28% C and 16.84% G with AT bias of 54.88%. The complete mitogenome of M. omeiensis provides the basis for genetic resources and phylogenetic analyses on this freshwater fish species. PMID:25162765

  12. Male gonadal differentiation and the paedomorphic evolution of the testis in Teleostei.

    PubMed

    Mazzoni, Talita Sarah; Grier, Harry J; Quagio-Grassiotto, Irani

    2014-06-01

    Testis differentiation from representatives of the Otophysi (Cyprinus carpio), Percomorpha (Amatitlania nigrofasciata), and Atherinomorpha (Poecilia reticulata) was comparatively described. In the undifferentiated gonad of C. carpio, the primordial germ cells (PGCs) are scattered throughout the gonads while in A. nigrofasciata and P. reticulata the PGCs are restricted to the ventral periphery. In the dorsal region of the developing gonads, with the exception of C. carpio, somatic cell rearrangements result in the differentiation of the sperm duct. Pre-Sertoli cells wrap around single spermatogonia forming cysts that proliferate forming acinar-clusters. In C. carpio and A. nigrofasciata, the cysts in each acinar-cluster move away from each other, creating a central lumen. In C. carpio, the acinar-clusters then fuse to each other forming tubules that become lined by the germinal epithelium. Subsequently, the tubules anastomose dorsally and create the sperm duct. In A. nigrofasciata, the acinar-clusters elongate, forming lobules that individually connect to the sperm duct. These are lined by the germinal epithelium. In P. reticulata, the spermatogonial cysts remain in the acinar-cluster organization. Subsequently, developing ducts connect each cluster to the sperm duct and lobules subsequently develop. In the differentiated testis of C. carpio and A. nigrofasciata, spermatogonia are distributed along the lengths of the anastomosing tubules or lobules, respectively. However, in P. reticulata, the spermatogonia remain restricted to the terminal end of the lobules. Considering testis ontogeny, the spermatogonial acinar-cluster is the adult characteristic of more derived taxa that approximate the early gonad developmental stages of the basal taxa. PMID:24740886

  13. First record of the Atlantic bumper Chloroscombrus chrysurus (Teleostei: Carangidae) in the Mediterranean Sea.

    PubMed

    Pea Rivas, L; Azzurro, E; Lloris, D

    2013-03-01

    In December 1997, one specimen of the Atlantic bumper, Chloroscombrus chrysurus was recorded for the first time in the Mediterranean Sea, off Almucar (Granada, Spain: 36?43'?26??N; 3?41'?39??W). This species probably entered the Mediterranean Sea via the Strait of Gibraltar. PMID:23464561

  14. The complete mitochondrial genome of Schizothorax chongi (Fang, 1936) (Teleostei, Cyprinidae, Schizothoracinae).

    PubMed

    Que, Yan-Fu; Xu, Dong-Mei; Li, Wei-Tao; Yang, Zhi; Tang, Hui-Yuan; Shao, Ke

    2016-03-01

    Schizothorax chongi is an endemic and important polyploidy fish in the upper stream of the Yangtze River. S. chongi represents a typical model species to study historical adaptation and evolution in the Tibetan Plateau. In this study, the complete mitochondrial DNA genome sequence of S. chongi was first determined by DNA sequencing based on the PCR fragments. The complete mitochondrial DNA (mtDNA) genome sequence of S. chongi is a circular molecule of 16,584?bp in length. It consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a control region (D-loop). The gene nucleotide composition of S. chongi is 29.6% A, 27.1% C, 17.9% G, and 25.4% T, with a high AT content (55.0%). The results could provide useful data for further studies on phylogenetics, conservation genetics and rational resource management for S. chongi. PMID:24865916

  15. Cryptic Diversity and Venom Glands in Western Atlantic Clingfishes of the Genus Acyrtus (Teleostei: Gobiesocidae)

    PubMed Central

    Conway, Kevin W.; Baldwin, Carole; White, Macaulay D.

    2014-01-01

    Examination of genetic data (mitochondrial cytochrome c oxidase I) for western Atlantic clingfishes revealed two distinct lineages within a group of individuals originally identified as Acyrtus artius. Subsequent investigation of preserved voucher specimens was conducted to reconcile the genetic data and the existing classification, which is based on morphology. In addition to discovering that one of the genetic lineages is an undescribed species, which we describe as Acyrtus lanthanum, new species, we found that the nominal species Acyrtus artius has a putative venom gland associated with the subopercle that has been overlooked since the species was described nearly 60 years ago. The new species lacks the subopercular gland as does Acyrtus rubiginosus, but one is present in the related Arcos nudus. Venom glands have not been reported previously for the Gobiesocidae, and the venom gland described herein for Acyrtus and Arcos represents the first example in teleost fishes of a venom gland associated with the subopercle. PMID:24825326

  16. Taxonomic status of Tetragonopterus anomalus Steindachner, 1891, an inquirenda species in Characidae (Teleostei: Characiformes).

    PubMed

    Carvalho, Fernando R; Santos, Ana Cláudia

    2015-01-01

    Tetragonopterus anomalus Steindachner was briefly described in July of 1891 (Steindachner 1891a:173) solely based on the holotype, which measured 144 mm (probably SL). Subsequently, in October, Steindachner (1891b:369) illustrated and redescribed the species in more detail. The type specimen was collected in the Paraná River, in the vicinity of Corrientes, Argentina. A few months before, in April of the same year, Perugia (1891:643) described Tetragonopterus nigripinnis, from de la Plata River. Ulrey (1895:273) considered T. anomalus as a junior synonym of T. nigripinnis, but did not justify the reasons for this synonymy, which was later supported by Perugia (1897:25). Eigenmann (1903:145) proposed the genus Markiana, with T. nigripinnis (= M. nigripinnis) as type species (type by monotypy), but did not mention T. anomalus in the description of this genus. However, in his later review of Markiana, Eigenmann (1918:124) confirmed T. anomalus as a junior synonym of Markiana nigripinnis, followed also by Fowler (1948:136). Nonetheless, uncertainty about the taxonomic status of T. anomalus, a poorly known species, led Lima et al. (2003:161) to consider it an inquirenda species in Characidae, and this status has been maintained until the present (Eschmeyer 2015). PMID:26624034

  17. Molecular phylogeny of the Neotropical fish genus Tetragonopterus (Teleostei: Characiformes: Characidae).

    PubMed

    Melo, Bruno F; Benine, Ricardo C; Silva, Gabriel S C; Avelino, Gleisy S; Oliveira, Claudio

    2016-01-01

    Tetragonopterinae encompasses characid species of the genus Tetragonopterus, which are widely distributed throughout east of the Andes in South America. While taxonomy has recently clarified the species diversity and molecular evidence strongly supports the monophyly of Tetragonopterus, no interspecific relationship studies are currently available. Here we used a large molecular dataset composed of two mitochondrial and three nuclear loci containing an extensive taxon sampling within the family Characidae and included eleven species of Tetragonopterus to generate the first time-calibrated phylogeny for Tetragonopterinae. Our results support monophyly of the subfamily represented solely by Tetragonopterus and corroborate previous molecular hypothesis of close relationship with Exodon plus Roeboexodon and the subfamily Characinae. Internally, we found Moenkhausia georgiae as sister species to all remaining species followed by T. rarus, being both species endemic to the Guiana Shield drainages. Species-level relationships are first hypothesized and putative morphological apomorphies are discussed as support to monophyletic clades. Our time-calibrated phylogeny suggested an origin of the genus during the Late Oligocene-Early Miocene. We hypothesized that the Andean geological activity followed by transformations in the Amazonian hydrographic scenario during the Miocene may have promoted most of the lineage diversification within the Tetragonopterus. PMID:26541240

  18. Phylogeny and biogeography of Triportheidae (Teleostei: Characiformes) based on molecular data.

    PubMed

    Mariguela, T C; Roxo, F F; Foresti, F; Oliveira, C

    2016-03-01

    Triportheidae represents a relatively small family of characiform fishes with highly modified morphology. The relationship among characiform families is still unclear, and a phylogenetic analysis for the family including a representative number of Triportheus species has never been performed. Here, we inferred a phylogeny for 19 of the 22 species recognized for this family and two possible new Triportheus species using two mitochondrial and three nuclear genes. Our results show that (1) Triportheidae is monophyletic and a sister group of the clade consisting of the families Bryconidae and Gasteropelecidae; (2) Triportheus is monophyletic, but some species need to be reviewed and described; (3) all genera in Triportheidae, except for Agoniates originated in the period between Early Oligocene and Early Miocene; and (4) speciation in Triportheidae coincides with important geological events in South America, reinforcing the importance of time-calibrated trees to study fish evolution. PMID:26721557

  19. New insights into karyotypic relationships among populations of Astyanax bockmanni (Teleostei, Characiformes) of different watersheds.

    PubMed

    Daniel, Sandro Natal; Penitente, Manolo; Hashimoto, Diogo Teruo; de Andrade Silva, Duílio Mazzoni Zerbinato; Foresti, Fausto; Porto-Foresti, Fábio

    2015-04-01

    The fish constitute about 50% of all vertebrates, including a wide morphological and biological diversity, where the genus Astyanax is the most common and diverse, as described in virtually all freshwater environments. By occupying a basal position in the phylogeny of vertebrates, fish are an extremely favorable group for cytogenetic and evolutionary studies. The karyotype found in genus Astyanax diversity may involve a number of polymorphisms, which may be related to ploidy and karyotypic macrostructure, presence of B chromosomes, heterochromatin polymorphisms, and location of ribosomal genes. Nevertheless, the relationship between populations of this species is still poorly studied. Thus, the present work aimed to investigate karyotype variation, chromosomal relationships, and the behavior of 5S and 18S ribosomal genes in six populations of Astyanax bockmanni. The results confirmed the diploid number of 50 chromosomes in all the populations sampled, with the occurrence of one supernumerary chromosome in just one of them. In addition, all populations showed divergent patterns of constitutive heterochromatin and repetitive nucleolar sites. The fluorescence in situ hybridization (FISH) technique using 5S and 18S rDNA probes revealed distinct patterns of distribution for these conserved genes, while 5S rDNA genes were found located in two chromosome pairs, the 18S genes showed multiple marks dispersed in the genome characterizing an inter and intraindividual polymorphic behavior, as previously reported to occur with the utilization of the Ag-NOR technique. Thus, besides minor modifications observed in chromosome morphology, the populations of A. bockmanni analyzed revealed a preserved macrostructural feature, especially concerning to the diploid number; on the other hand, differences in microstructural characteristics indicated by the nucleolus organizer region (NOR) location, constitutive heterochromatin patterns, and distribution of ribosomal genes along the genome were clearly evident in the populations from different river basins, even located at short distances. PMID:25714526

  20. Taxonomic revision and molecular phylogeny of Gymnocorymbus Eigenmann, 1908 (Teleostei, Characiformes, Characidae).

    PubMed

    Benine, Ricardo C; Melo, Bruno F; Castro, Ricardo M C; Oliveira, Claudio

    2015-01-01

    Characidae, one of the most diverse families of Characiformes and one of the largest clades of fishes in the world, has a complex taxonomic background, with one issue being the placement of various genera, including Gymnocorymbus. Herein, we generate the first molecular phylogeny for the genus using three nuclear and two mitochondrial loci and review the systematics of Gymnocorymbus. This genus includes the black tetra, a well-known and popular species among aquarists. Molecular phylogeny strongly supports the monophyly of Gymnocorymbus, with this hypothesis corroborated by the presence of three morphological synapomorphies. Of the six previously known nominal species of Gymnocorymbus, three are considered valid herein: Gymnocorymbus bondi from the Río Orinoco basin, Gymnocorymbus ternetzi from the Rio Paraguay basin, and Gymnocorymbus thayeri from the Corantijn and Amazon basin and rivers of northeastern Brazil. A fourth species, Gymnocorymbus flaviolimai sp. n., is described from the Rio Madeira, Amazon basin. Lectotypes are designated for G. ternetzi and G. thayeri. Our results support previous hypotheses of the alignment of Gymnocorymbus close to the subfamily Stethaprioninae and also support the sister relationship between G. ternetzi and G. thayeri, and of that clade as sister to G. bondi. PMID:26248902

  1. Cytogenetic study of heptapterids (Teleostei, Siluriformes) with particular respect to the Nemuroglanis subclade

    PubMed Central

    Kantek, Daniel Luis Zanella; Moreira Peres, Wellington Adriano; Moreira-Filho, Orlando

    2015-01-01

    Abstract The catfish family Heptapteridae (order Siluriformes) is endemic to the Neotropics and is one of the most common of the fish families in small bodies of water. Although over 200 species have been identified in this family, very few have been characterized cytogenetically. Here, we analyze the chromosome genomes of four species of Heptapteridae: Cetopsorhamdia iheringi (Schubart & Gomes, 1959), 2n = 58, comprising 28 metacentric (m) + 26 submetacentric (sm) + 4 subtelomeric (st) chromosomes; Pimelodella vittata (Lütken, 1874), 2n = 46, comprising 16m + 22sm + 8st; Rhamdia prope quelen (Quoy & Gaimard, 1824), 2n = 58 comprising 26m + 16sm + 14st + 2 acrocentric; and Rhamdiopsis prope microcephala (Lütken, 1874), 2n = 56, comprising 12m + 30sm + 14st. The nucleolus organizer regions (NORs) were located in a single chromosome pair in all species. The two species that belonged to the subclade Nemuroglanis, Cetopsorhamdia iheringi and Rhamdia prope quelen, had a diploid chromosome number of 58 and an interstitial NOR adjacent to a C+ block located on one of the larger chromosome pairs in the complement. Our results from conventional cytogenetic techniques in combination with FISH using 18S and 5S rDNA probes corroborated the taxonomical hypothesis for the formation of the Nemuroglanis subclade. PMID:25893072

  2. Identification and chromosome mapping of repetitive elements in the Astyanax scabripinnis (Teleostei: Characidae) species complex.

    PubMed

    Barbosa, Patrícia; de Oliveira, Luiz Antonio; Pucci, Marcela Baer; Santos, Mateus Henrique; Moreira-Filho, Orlando; Vicari, Marcelo Ricardo; Nogaroto, Viviane; de Almeida, Mara Cristina; Artoni, Roberto Ferreira

    2015-02-01

    Most part of the eukaryotic genome is composed of repeated sequences or multiple copies of DNA, which were considered as "junk DNA", and may be associated to the heterochromatin. In this study, three populations of Astyanax aff. scabripinnis from Brazilian rivers of Guaratinguetá and Pindamonhangaba (São Paulo) and a population from Maringá (Paraná) were analyzed concerning the localization of the nucleolar organizer regions (Ag-NORs), the As51 satellite DNA, the 18S ribosomal DNA (rDNA), and the 5S rDNA. Repeated sequences were also isolated and identified by the Cot - 1 method, which indicated similarity (90%) with the LINE UnaL2 retrotransposon. The fluorescence in situ hybridization (FISH) showed the retrotransposon dispersed and more concentrated markers in centromeric and telomeric chromosomal regions. These sequences were co-localized and interspaced with 18S and 5S rDNA and As51, confirmed by fiber-FISH essay. The B chromosome found in these populations pointed to a conspicuous hybridization with LINE probe, which is also co-located in As51 sequences. The NORs were active at unique sites of a homologous pair in the three populations. There were no evidences that transposable elements and repetitive DNA had influence in the transcriptional regulation of ribosomal genes in our analyses. PMID:25549800

  3. Extensive spreading of interstitial telomeric sites on the chromosomes of Characidium (Teleostei, Characiformes).

    PubMed

    Scacchetti, Priscilla Cardim; Utsunomia, Ricardo; Pansonato-Alves, José Carlos; da Costa-Silva, Guilherme José; Oliveira, Claudio; Foresti, Fausto

    2015-06-01

    Characidium comprises several species of small freshwater fish that display conserved diploid chromosome numbers and karyotypic formulae. In this study, a comparative cytogenetic analysis using telomeric DNA probes was carried out in nine species of Characidium; a molecular phylogenetic analysis with mitochondrial DNA was also performed in order to investigate the direction of the evolutionary chromosome changes observed here. Our results showed the existence of species with several and variable interstitial telomeric sites (ITSs), with other species showing only terminal signals in their chromosomes. Molecular phylogenetic data suggested that these ITSs emerged once in the evolutionary history of Characidium and were later differentially spread in distinct species/populations of this clade. Additionally, the origin of an exclusive acrocentric pair found in C. pterostictum, C. serrano and C. timbuiense was also investigated, revealing that this pair possibly had a common origin to these species. These results evidence the occurrence of intense and continuous genomic changes among species of Characidium. PMID:25547849

  4. Mitochondrial DNA variability to explore the relationship complexity of Schizothoracine (Teleostei: Cyprinidae).

    PubMed

    Ahmad, Syed Mudasir; Bhat, Farooz Ahmad; Balkhi, Masood-Ul Hassan; Bhat, Bilal Ahmad

    2014-12-01

    Despite numerous studies on the taxonomy of a highly complex group of schizothoracine (snow trouts), with over five recognized species from Kashmir, India (Schizothorax niger, Schizothorax esocinus, Schizothorax plagiostomus, Schizothorax curvifrons and Schizothorax labiatus) based on traditional morphological data, the relationships between these species is poorly understood and the taxonomic validity is still under debate. To resolve the evolutionary relationships among these species, we sequenced mitochondrial fragments, including 16Sr RNA, Cytb and the D-loop. Separate analyses of 16S and Cytb showed intermixing of the species and 16S was found more conserved than Cytb. The D-loop was found highly variable and showed length variation between and within species. Length variation was observed in di-nucleotide (TA)n microsatellite repeats with a variable number of repeat units (n = 7-14) that did not show heteroplasmy. Central conserved sequence blocks (CSBs) in D-loop sequences were found comparable to other vertebrate species. All phylogenetic reconstructions recovered the focal taxa as a monophyletic clade within the schizothoracines. Analyses with combined mitochondrial data sets showed close genetic relationships of all the five species. In addition to a close relationship between S. niger and S. curvifrons, two distinct groupings of S. ecoscinus and S. plagiostomus were supported by all the analyses. This study gives an insight into molecular phylogeny of the species and improves our understanding of historical and taxonomic relationships derived from morphological and ecological studies. PMID:25366848

  5. Stone loaches of Choman River system, Kurdistan, Iran (Teleostei: Cypriniformes: Nemacheilidae).

    PubMed

    Kamangar, Barzan Bahrami; Prokofiev, Artem M; Ghaderi, Edris; Nalbant, Theodore T

    2014-01-01

    For the first time, we present data on species composition and distributions of nemacheilid loaches in the Choman River basin of Kurdistan province, Iran. Two genera and four species are recorded from the area, of which three species are new for science: Oxynoemacheilus kurdistanicus, O. zagrosensis, O. chomanicus spp. nov., and Turcinoemacheilus kosswigi B?n. et Nalb. Detailed and illustrated morphological descriptions and univariate and multivariate analysis of morphometric and meristic features are for each of these species. Forty morphometric and eleven meristic characters were used in multivariate analysis to select characters that could discriminate between the four loach species. Discriminant Function Analysis revealed that sixteen morphometric measures and five meristic characters have the most variability between the loach species. The dendrograms based on cluster analysis of Mahalanobis distances of morphometrics and a combination of both characters confirmed two distinct groups: Oxynoemacheilus spp. and T. kosswigi. Within Oxynoemacheilus, O. zagrosensis and O. chomanicus are more similar to one other rather to either is to O. kurdistanicus. PMID:24869808

  6. Lake Tanganyika--a 'melting pot' of ancient and young cichlid lineages (Teleostei: Cichlidae)?

    PubMed

    Weiss, Juliane D; Cotterill, Fenton P D; Schliewen, Ulrich K

    2015-01-01

    A long history of research focused on the East Africa cichlid radiations (EAR) revealed discrepancies between mtDNA and nuclear phylogenies, suggesting that interspecific hybridisation may have been significant during the radiation of these fishes. The approximately 250 cichlid species of Lake Tanganyika have their roots in a monophyletic African cichlid assemblage, but controversies remain about the precise phylogenetic origin and placement of different lineages and consequently about L. Tanganyika colonization scenarios. 3312 AFLP loci and the mitochondrial ND2 gene were genotyped for 91 species representing almost all major lacustrine and riverine haplotilapiine east African cichlid lineages with a focus on L. Tanganyika endemics. Explicitly testing for the possibility of ancient hybridisation events, a comprehensive phylogenetic network hypothesis is proposed for the origin and diversification of L. Tanganyika cichlids. Inference of discordant phylogenetic signal strongly suggests that the genomes of two endemic L. Tanganyika tribes, Eretmodini and Tropheini, are composed of an ancient mixture of riverine and lacustrine lineages. For the first time a strong monophyly signal of all non-haplochromine mouthbrooding species endemic to L. Tanganyika ("ancient mouthbrooders") was detected. Further, in the genomes of early diverging L. Tanganyika endemics Trematocarini, Bathybatini, Hemibatini and Boulengerochromis genetic components of other lineages belonging to the East African Radiation appear to be present. In combination with recent palaeo-geological results showing that tectonic activity in the L. Tanganyika region resulted in highly dynamic and heterogeneous landscape evolution over the Neogene and Pleistocene, the novel phylogenetic data render a single lacustrine basin as the geographical cradle of the endemic L. Tanganyika cichlid lineages unlikely. Instead a scenario of a pre-rift origin of several independent L. Tanganyika precursor lineages which diversified in ancient rivers and precursor lakes and then amalgamated in the extant L. Tanganyika basin is put forward as an alternative: the 'melting pot Tanganyika' hypothesis. PMID:25928886

  7. Descriptions of five new species of Metriaclima (Teleostei: Cichlidae) from Lake Mala?i, Africa.

    PubMed

    Stauffer, Jay R; Black, Kristin; Konings, Adrianus F

    2013-01-01

    Lake Mala?i is known for its endemic haplochromine species flock, most notably the rock-dwelling cichlids known as mbuna. One of the larger genera of mbuna is Metriaclima, a group consisting of 31 described species (including the five described herein) and approximately 45 recognized unique populations. Metriaclima is diagnosed by its feeding behavior and several morphological characteristics including the angle of the vomer and the presence of bicuspid teeth in the outer row of both the upper and lower jaws. Metriaclima zebra, the type species for the genus, was described based on a single specimen. While the collection location of this holotype is not known, based on the travel records of its collector, it is likely that the specimen originated from Likoma Island. The holotype was therefore compared to specimens from several localities around this island and was found to be morphologically indistinguishable from some of these. This study includes the morphological analysis of 496 specimens of Metriaclima belonging to 31 collections from Lake Mala?i. Morphometric differences were analyzed and the relationships among several distinguishable populations of Metriaclima zebra were investigated. Our study further resulted in the description of the following five new species belonging to the M. zebra species complex: M. pambazuko, M. lundoense, M. midomo, M. tarakiki, and M. nigrodorsalis. These species were distinguished and described based on color patterns, morphometric, meristic, and ecological differences. These new species were compared with and distinguished from nearby populations of Metriaclima having similar pigmentation patterns and/or similar ecological niches. An artificial dichotomous key to the described species of Metriaclima is presented. PMID:26295101

  8. Developmental stages until hatching of the Lake Victoria cichlid Haplochromis piceatus (Teleostei: Cichlidae).

    PubMed

    de Jong, Ilse M L; Witte, Frans; Richardson, Michael K

    2009-05-01

    Because little is known about embryonic developmental stages in any haplochromine cichlid, we describe here a series of normal stages of the Lake Victoria cichlid Haplochromis piceatus. We collected 273 embryos and scored them for 47 morphological characters. The result was an illustrated series of 12 stages from embryonic shield until hatching based on live, fixed, and histological material. We defined each stage according to a single "key" character that applied to all embryos of that stage. Other characters forming part of the stage descriptions were not necessarily present in all embryos of a stage. We compare our findings with published studies of other freshwater teleosts and find wide variation in staging systems. Our data will form a baseline for further research on cichlid development. PMID:19123243

  9. Whole chromosome painting of B chromosomes of the red-eye tetra Moenkhausia sanctaefilomenae (Teleostei, Characidae)

    PubMed Central

    Scudeler, Patricia Elda Sobrinho; Diniz, Débora; Wasko, Adriane Pinto; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    Abstract B chromosomes are dispensable genomic elements found in different groups of animals and plants. In the present study, a whole chromosome probe was generated from a specific heterochromatic B chromosome occurring in cells of the characidae fish Moenkhausia sanctaefilomenae (Steindachner, 1907). The chromosome painting probes were used in fluorescence in situ hybridization (FISH) experiments for the assessment of metaphase chromosomes obtained from individuals from three populations of Moenkhausia sanctaefilomenae. The results revealed that DNA sequences were shared between a specific B chromosome and many chromosomes of the A complement in all populations analyzed, suggesting a possible intra-specific origin of these B chromosomes. However, no hybridization signals were observed in other B chromosomes found in the same individuals, implying a possible independent origin of B chromosome variants in this species. FISH experiments using 18S rDNA probes revealed the presence of non-active ribosomal genes in some B chromosomes and in some chromosomes of the A complement, suggesting that at least two types of B chromosomes had an independent origin. The role of heterochromatic segments and ribosomal sequences in the origin of B chromosomes were discussed. PMID:26753081

  10. A new marine gobiid species of the genus Clariger Jordan & Snyder (Gobiidae, Teleostei) from Taiwan

    PubMed Central

    Jang-Liaw, Nian-Hong; Gong, You-Hai; Chen, I-Shiung

    2012-01-01

    Abstract A new species of Clariger Jordan & Snyder, 1901 was collected from northern Taiwan. The genus was previously known only from Japanese waters. This discovery is the first formal and southernmost record of these marine gobies from the waters of subtropical Taiwan. The new species, Clariger taiwanensis sp. n., is distinguished from its congeners by a unique combination of features: (1) fin rays: dorsal-fin rays III, I/8; anal-fin rays modally I/8; and pectoral-fin rays modally 19 (2+16+1); (2) longitudinal dermal ridge on head with 6 barbels; and (3) specific coloration pattern: head and trunk dark brown with scattered pale spots and blotches; cheek, ventral portion of head sometimes pale with deep brown spots; pectoral-fin base with a dark brown band; and caudal fin mostly dark brown proximally and with alternating and irregular dark brown and pale bands distally. A diagnostic key to all nominal species from Japan and Taiwan is provided. PMID:22711994

  11. A new species of redfin (Teleostei, Cyprinidae, Pseudobarbus) from the Verlorenvlei River system, South Africa

    PubMed Central

    Chakona, Albert; Swartz, Ernst R.; Skelton, Paul H.

    2014-01-01

    Abstract Pseudobarbus verloreni, a new species, is described from material collected in the Verlorenvlei River system on the west coast of South Africa. It differs from its congeners (except Pseudobarbus skeltoni, Pseudobarbus burchelli, and Pseudobarbus burgi) by the presence of two pairs of oral barbels. Pseudobarbus verloreni sp. n. can be distinguished from the three currently described double barbeled Pseudobarbus species by the following combination of characters: pigment pattern, generally deeper body relative to standard length, a longer intestine associated with the deeper body form, shorter snout relative to head length, and much shorter anterior barbels relative to head length. The new species is distinguished from Pseudobarbus burgi in the neighbouring Berg River system by its longer head and longer pre-dorsal length. It seems as if Pseudobarbus verloreni sp. n. has been extirpated from the Langvlei River system and face several threats to its survival in the Verlorenvlei River system. PMID:25493062

  12. Genetic differentiation among natural populations of the Nile tilapia Oreochromis niloticus (Teleostei, cichlidae).

    PubMed

    Agnse, J F; Adpo-Gourne, B; Abban, E K; Fermon, Y

    1997-07-01

    We analysed the genetic differentiation among 17 natural populations of the Nile tilapia Oreochromis niloticus (Linnaeus, 1758) using allozymes and restriction fragment length polymorphism (RFLP) of mitochondrial DNA (mtDNA). The populations studied, from the River Senegal to Lake Tana and from Lake Manzalla to Lake Baringo, represent all subspecies which have been previously described. Sixteen variable nuclear loci showed that these populations can be clustered in three groups: (1) West African populations (Senegal, Niger, Volta and Chad drainages), (2) Ethiopian Rift Valley populations (Lakes Awasa, Ziway, Koka and the Awash River) and (3) Nile drainage (Manzalla, Cairo, Lake Edward) and Kenyan Rift Valley populations (Lakes Turkana, Baringo and River Suguta). Nine different mtDNA haplotypes were found in the RFLP analysis of a 1 kb portion of the D-loop region. The network obtained showed that there are three geographically distinct groups; all West African populations and O. aureus are clustered, the two Ethiopian Rift Valley populations are distinct and between these two groups are the Kenyan and Ugandan Rift Valley populations. Nile populations show affinities both with West African populations and with specimens from Lakes Tana and Turkana. Taxonomic and biogeographical implications of these results are discussed. PMID:9253615

  13. A new species of Barbatula from the Russian Altai (Teleostei: Nemacheilidae).

    PubMed

    Prokofiev, Artem M

    2015-01-01

    Barbatula restricta, new species, is described from the Saldan-Kol Lake in the upper Ob River drainage in the Altai Mountains. It is distinguished from all other species of Barbatula in Asia by its body depth increasing continuously between the nape and the dorsal-fin origin and a combination of characters: nares widely spaced, upper lip with a short medial incision, lower lip without lateral expansions, mental lobes of lower lip without conical protrusions, tips of paired fins formed by 1st and 2nd branched rays, 42-45 (mean 44) vertebrae, color pattern consisting of small irregular mottles without saddles on back. An overview of the status of all nominal Asiatic Barbatula species described is given. PMID:26701442

  14. Two new species of the genus Cobitis linnaeus (Teleostei: Cobitidae) from southern China

    NASA Astrophysics Data System (ADS)

    Chen, Yongxia; Sui, Xiaoyun; Liang, Na; Chen, Yifeng

    2015-10-01

    Two new species of the genus Cobitis from southern China, C. hereromacula from the Luohe River in Guangdong Province and C. baishagensis from the Nandujiang River in Hainan Province, are described and illustrated here. C. hereromacula can be distinguished from its congeners by possessing the following combination of characteristics: absence of the second and third pigmentary zones of Gambetta; 13-16 oval blotches on the dorsum and 10-13 vertical, elongated triangular blotches below the midlateral line with more than 20 vertical dark brown bars between them; 6-7 narrow rows of dark spots on the caudal fin; a vertical oval spot smaller than the eye diameter on the upper part of the caudal peduncle; pointed mental lobes of the lower lip pointed with a slightly filiform tip; one slender and long needle-shaped lamina circularis at the base of the first branched ray of the male pectoral fins. C. baishagensis can be distinguished from its congeners by the fourth Gambetta zone being covered by 10-12 transverse elongated blotches; 4-5 narrow rows of dark spots on the caudal fin; a vertical blotch smaller than the eye diameter on the upper part of the caudal peduncle; males with a slender and long needle-shaped lamina circularis at the second branched pectoral fin ray in males; large scales with a slightly large focal zone; undeveloped mental lobes with a lower lip that does not end posteriorly in a filiform tip.

  15. Spermatozoon ultrastructure of Aponurus laguncula (Digenea: Lecithasteridae), a parasite of Aluterus monoceros (Pisces: Teleostei).

    PubMed

    Quilichini, Y; Foata, J; Justine, J-L; Bray, R A; Marchand, B

    2010-03-01

    The mature spermatozoon of Aponurus laguncula, a parasite of the unicorn leatherjacket Aluterus monoceros, was studied by transmission electron microscopy. The spermatozoon possesses 2 axonemes of the 9+"1" trepaxonematan pattern, attachment zones, a nucleus, a mitochondrion, external ornamentation of the plasma membrane and cortical microtubules. The major features are the presence of: 1) external ornamentation in the anterior part of the spermatozoon not associated with cortical microtubules; 2) one mitochondrion; and 3) cortical microtubules arranged as a single field in the ventral side. The maximum number of microtubules is in the nuclear region. The extremities of the axonemes are characterized by the disappearance of the central core and the presence of microtubule doublets or singlets. This study is the first undertaken with a member of the Lecithasteridae and exemplifies the sperm ultrastructure for the superfamily Hemiuroidea. PMID:19559102

  16. Complete mitochondrial genome of the Chinese lizard gudgeon, Saurogobio dabryi (Teleostei: Cypriniformes: Cyprinidae).

    PubMed

    Xu, Hao; Xue, Yang; Li, Xin-Yue; Luo, Xi; Li, Yang; Li, Yun

    2015-12-01

    The Chinese lizard gudgeon, Saurogobio dabryi Bleeker, belongs to the subfamily Gobioninea, which is an economic fish widely distributed in East Asia. In this study, we sequenced the complete mitochondrial genome of the S. dabryi. The complete mitogenome was 16,601 bp in size, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and 1 control region. It has the typical circular molecule structure of vertebrate's mitochondrial genome. The whole base composition was estimated to be 29.64%A, 26.47%T, 27.06%C and 16.83%G with AT bias of 56.11%. This study is a first report the complete mitogenome of S. dabryi and provides the basis for preservation of genetic resources and phylogenetic analyses on this species. PMID:24409846

  17. Herbivory Promotes Dental Disparification and Macroevolutionary Dynamics in Grunters (Teleostei: Terapontidae), a Freshwater Adaptive Radiation.

    PubMed

    Davis, Aaron M; Unmack, Peter J; Vari, Richard P; Betancur-R, Ricardo

    2016-03-01

    Trophic shifts into new adaptive zones have played major (although often conflicting) roles in reshaping the evolutionary trajectories of many lineages. We analyze data on diet, tooth, and oral morphology and relate these traits to phenotypic disparification and lineage diversification rates across the ecologically diverse Terapontidae, a family of Australasian fishes. In contrast to carnivores and most omnivores, which have retained relatively simple, ancestral caniniform tooth shapes, herbivorous terapontids appear to have evolved a variety of novel tooth shapes at significantly faster rates to meet the demands of plant-based diets. The evolution of herbivory prompted major disparification, significantly expanding the terapontid adaptive phenotypic continuum into an entirely novel functional morphospace. There was minimal support for our hypothesis of faster overall rates of integrated tooth shape, spacing, and jaw biomechanical evolution in herbivorous terapontids in their entirety, compared with other trophic strategies. There was, however, considerable support for accelerated disparification within a diverse freshwater clade containing a range of specialized freshwater herbivores. While the evolutionary transition to herbivorous diets has played a central role in terapontid phenotypic diversification by pushing herbivores toward novel fitness peaks, there was little support for herbivory driving significantly higher lineage diversification compared with background rates across the family. PMID:26913945

  18. New approach data in electric fish (Teleostei: Gymnotus): sex chromosome evolution and repetitive DNA.

    PubMed

    da Silva, Maelin; Matoso, Daniele Aparecida; Artoni, Roberto Ferreira; Feldberg, Eliana

    2014-12-01

    Antagonist sexual selection is the driving force behind the origin and diversification of sex chromosomes such as XX/XY and ZZ/ZW. However, chromosome mobility, mainly in fishes, may result in the formation of chromosomes of recent origin, a process known as turnover. The family Gymnotidae, which is composed of the genera Electrophorus+Gymnotus, presents a multiple system of the type X1X1X2X2/X1X2Y, which has been described for Gymnotus pantanal. This article describes the karyotype of three Amazon Gymnotus species, revealing the presence of both simple and multiple systems: Gymnotus carapo "Catalo" 2n=40 XX/XY, Gymnotus coropinae 2n=49?/50? X1X1X2X2/X1X2Y, and Gymnotus sp. "Negro" 2n=50 XX/XY. Our hypothesis is that the simple system present in G. carapo "Catalo" is ancestral in relation to G. pantanal's multiple system and that the diversification of the subsequent multiple system occurred after the final separation of the Amazon and Paran basins. Moreover, G. coropinae's multiple system may have originated from the simple system present in Gymnotus sp. "Negro." The distant position between the species in the Gymnotidae family's phylogeny in addition to differences in sex chromosome formula and number between Clade G1 G. coropinae and G. sp. "Negro" species and "Carapo" Clade. G. carapo and G. pantanal species suggest that both sequences of sexual systems occurred independently, supporting other proposed models and highlighting the fact that species of the genus Gymnotus may serve as a model for studying sex chromosome turnover. PMID:25264714

  19. Mitogenomic evidence for an Indo-West Pacific origin of the Clupeoidei (Teleostei: Clupeiformes).

    PubMed

    Lavoué, Sébastien; Miya, Masaki; Musikasinthorn, Prachya; Chen, Wei-Jen; Nishida, Mutsumi

    2013-01-01

    The clupeoid fishes are distributed worldwide, with marine, freshwater and euryhaline species living in either tropical or temperate environments. Regional endemism is important at the species and genus levels, and the highest species diversity is found in the tropical marine Indo-West Pacific region. The clupeoid distribution follows two general pattern of species richness, the longitudinal and latitudinal gradients. To test historical hypotheses explaining the formation of these two gradients, we have examined the early biogeography of the Clupeoidei in reconstructing the evolution of their habitat preferences along with their ancestral range distributions on a time-calibrated mitogenomic phylogeny. The phylogenetic results support the distinction of nine main lineages within the Clupeoidei, five of them new. We infer several independent transitions from a marine to freshwater environment and from a tropical to temperate environment that occurred after the initial diversification period of the Clupeoidei. These results combined with our ancestral range reconstruction hypothesis suggest that the probable region of origin and diversification of the Clupeoidei during the Cretaceous period was the tropical marine precursor to the present Indo-West Pacific region. Thus, our study favors the hypotheses of "Region of origin" and "Tropical conservatism" to explain the origins of the longitudinal and latitudinal gradients of clupeoid species richness, respectively. Additional geological and paleontological evidence further define the tropical marine paleo-region of origin as the eastern Tethys Sea region. The Cretaceous fossil record of the Clupeoidei is partially incongruent with the results here as it contains taxa found outside this region. We discuss three possible causes of conflict between our biogeographical hypothesis and the distributions of the Cretaceous clupeoid fossils: regional extinction, incomplete taxonomic sampling and incorrect timescale estimation. PMID:23431379

  20. Is sexual selection driving diversification of the bioluminescent ponyfishes (Teleostei: Leiognathidae)?

    PubMed

    Chakrabarty, Prosanta; Davis, Matthew P; Smith, W Leo; Baldwin, Zachary H; Sparks, John S

    2011-07-01

    Sexual selection may facilitate genetic isolation among populations and result in increased rates of diversification. As a mechanism driving diversification, sexual selection has been invoked and upheld in numerous empirical studies across disparate taxa, including birds, plants and spiders. In this study, we investigate the potential impact of sexual selection on the tempo and mode of ponyfish evolution. Ponyfishes (Leiognathidae) are bioluminescent marine fishes that exhibit sexually dimorphic features of their unique light-organ system (LOS). Although sexual selection is widely considered to be the driving force behind ponyfish speciation, this hypothesis has never been formally tested. Given that some leiognathid species have a sexually dimorphic LOS, whereas others do not, this family provides an excellent system within which to study the potential role of sexual selection in diversification and morphological differentiation. In this study, we estimate the phylogenetic relationships and divergence times for Leiognathidae, investigate the tempo and mode of ponyfish diversification, and explore morphological shape disparity among leiognathid clades. We recover strong support for a monophyletic Leiognathidae and estimate that all major ponyfish lineages evolved during the Paleogene. Our studies of ponyfish diversification demonstrate that there is no conclusive evidence that sexually dimorphic clades are significantly more species rich than nonsexually dimorphic lineages and that evidence is lacking to support any significant diversification rate increases within ponyfishes. Further, we detected a lineage-through-time signal indicating that ponyfishes have continuously diversified through time, which is in contrast to many recent diversification studies that identify lineage-through-time patterns that support mechanisms of density-dependent speciation. Additionally, there is no evidence of sexual selection hindering morphological diversity, as sexually dimorphic taxa are shown to be more disparate in overall shape morphology than nonsexually dimorphic taxa. Our results suggest that if sexual selection is occurring in ponyfish evolution, it is likely acting only as a genetic isolating mechanism that has allowed ponyfishes to continuously diversify over time, with no overall impact on increases in diversification rate or morphological disparity. PMID:21623980

  1. Gonad morphology, gametogenesis, and reproductive modes in fishes of the tribe Starksiini (Teleostei, Blenniiformes).

    PubMed

    Fishelson, Lev; Baldwin, Carole C; Hastings, Philip A

    2013-05-01

    A comparative study of the reproductive organs in 17 of the 30 species of the tribe Starksiini (Labrisomidae, Blenniiformes) and related labrisomids reveals the major traits of gamete form and production and likely reproductive modes. The testes are of the lobular type and have a testicular gland and sperm ducts. Isodiametric sperm (aquasperm) with a globular head or anisodiametric sperm (introsperm) with an elongate head, or both, were observed in the studied species. Both types have either one or two flagella in the sperm tail. Ovaries of the Starksiini are bilobed and exhibit synchronous or asynchronous egg production. Although viviparity or "ovoviviparity" reportedly characterizes the group, our study revealed evidence of both internal and external fertilization and three modes of reproduction. External fertilization or ovuliparity is suggested for the Starksia atlantica and S. lepicoelia species complexes by the presence in males of a short genital papilla that is not reinforced through adhesion with the first anal-fin spine and by the absence of sperm within the ovaries. Internal fertilization and zygoparity is indicated for most species by the presence of an intromittent papilla in males that is adhered to the first anal-fin spine, "nests" of sperm within the ovaries, absence of embryos within the ovarian lamellae and usually thick egg envelopes bearing dense covers of adhesive filaments. Internal fertilization and embryoparity is indicated for starksia fulva and Xenomedea rhodopyga by an intromittent papilla that is adhered to the first anal-fin spine of males, anisodiametric sperm in males, delicate egg envelopes without adhesive filaments and developing embryos within follicular envelopes or within the follicle in females. Although many of these features are seen in the internally fertilizing clinid blennies, starksiins differ in retaining the testicular gland typical of labrisomids and in lacking sperm packaging typical of other internally fertilizing teleosts. PMID:23293058

  2. The biology of Solea bleekeri (Teleostei) in Lake St Lucia on the southeast coast of Africa

    NASA Astrophysics Data System (ADS)

    Cyrus, D. P.

    Several aspects of the biology of Solea bleekeri in Lake St Lucia were investigated, these included occurrence, distribution, reproduction and recruitment, food and feeding, size frequency distribution and the role of estuaries in the species' life cycle. Solea bleekeri was found to occur throughout the system in muddy turbid areas and was largely absent from the eastern shores of the lake where clear water sandy substrata occur. The preferred diet of the species was bivalve siphon tips of the species Solon cylindraceus, when these were in abundant supply. However, when numbers of large (length > 20 mm) specimens were not available then S. bleekeri fed on whatever prey was available in or near the substratum. Analysis of stomach contents under the latter conditions showed that food consumption reflected the composition of the benthos. Large numbers of S. bleekeri spend their entire post-larval and juvenile phases as well as the greater part of their adult life within estuaries. Evidence is presented to support the idea that S. bleekeri breeds in certain areas of the lake and that spawning takes place between September and November. The current data suggest that there may be two populations in St Lucia: one migrates from the system to spawn at sea during winter along with the other marine fish species which utilize estuaries as nursery areas, while the other population breeds within the system. Alternatively there may simply be a single population which normally breeds at sea, but which may breed within the system when conditions are suitable. Recruitment of S. bleekeri into the St Lucia estuarine system takes place from the muddy offshore marine banks and possibly from within the system as well. Solea bleekeri appears not to be totally dependent on estuaries for the completion of its life cycle. The advantages of utilizing these systems for their development relate to the shallow, calm, turbid food-rich areas which estuaries offer. The fact that breeding takes place within St Lucia means that adults and juveniles are present in varying numbers throughout the year.

  3. Allopolyploidization is not so simple: evidence from the origin of the tribe Cyprinini (Teleostei: Cypriniformes).

    PubMed

    Ma, W; Zhu, Z-H; Bi, X-Y; Murphy, R W; Wang, S-Y; Gao, Y; Xiao, H; Zhang, Y-P; Luo, J

    2014-01-01

    The identification of allopolyploidization events benefits from molecular dating and divergence assessments of progenitor genomes. Information on gene duplications only, either orthologs or paralogs, provides incomplete information. Analyses of mitochondrial DNA yield insights into matrilineal history, which may differ from patrilineal evolution. Two important food and pet fishes, the common carp (Cyprinus carpio) and goldfish (Carassius sp.), appear to have experienced allotetraploidization sometime from 12 to 20 million years ago (Ma). However, much work is necessary to detail the initial polyploidization event. Herein, we use this group of fishes as a model system to investigate competing scenarios for allopolyploidization. We analyze both the nuclear genes encoding growth hormone (GH), recombination activating protein 1 (RAG1) and HOXA2B gene, and the maternal heredited 12 concatenated mitochondrial protein-coding gene in 19 species of cyprinids and use two species in Balitoridae as outgroup taxa. Our analyses clarify the phylogenetic position of the paternal and maternal ancestors for the common carp and goldfish. The estimation of matrilineal divergence (10.71-12.42 Ma) is significantly younger than the dates of the parental ancestor divergedthat obtained by nuclear genes (16.62-19.64 Ma). Analyses of both genomes date the allopolyploidization event of the common ancestor of Cy. carpio and Ca sp. to about 10.71-12.42 Ma, which is most likely represented by maternal divergent time. The divergence of the two copies of the nuclear genes which was more ancient than the maternal markers might have been included the divergence of the progenitors' genome divergence when the allopolyploidization event occurred. Thus, the scenarios of allopolyploidzation for this group of fish can be suggested as the following: the matrilineal common ancestor of species in tribe Cyprinini might have doubled its genome by mating with a paternal ancestor in the subfamily Cyprininae, which was a sister-group that diverged around 4.20-8.93 Ma. Our work provides new evidence for the divergence dates of allopolyploidization within the Cyprinini, and documents the necessity of considering both matrilineal and patrilineal histories when investigating allopolyploidization. PMID:25470283

  4. The complete mitogenome of the Murray Cod, Maccullochella peelii (Mitchell, 1838) (Teleostei: Percichthyidae).

    PubMed

    Austin, Christopher M; Tan, Mun Hua; Lee, Yin Peng; Croft, Laurence J; Gan, Han Ming

    2016-01-01

    The complete mitochondrial genome of the iconic Australian freshwater fish, the Murray Cod, Maccullochella peelii, was recovered from partial genome sequencing data using the HiSeq platform (Illumina, San Diego, CA). The mitogenome consists of 16,442 bp (58% A + T content) containing 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs, and a 768 bp non-coding AT-rich region. This is the first mitogenome sequence for the genus Maccullochella, and the fourth for the family Percichthyidae. PMID:24779601

  5. Steroid sex hormone dynamics during estradiol-17β induced gonadal differentiation in Paralichthys olivaceus (Teleostei)

    NASA Astrophysics Data System (ADS)

    Sun, Peng; You, Feng; Liu, Mengxia; Wu, Zhihao; Wen, Aiyun; Li, Jun; Xu, Yongli; Zhang, Peijun

    2010-03-01

    Steroid sex hormones, such as estradiol-17β (E2) and testosterone (T), are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gonadal differentiation in the olive flounder Paralichthys olivaceus using histology and radioimmunoassay (RIA). Flounder larvae were divided into five groups (G0-G4), and fed with 0 (control), 0.2, 2, 20 and 100 mg E2/kg feed from 35 to 110 day post hatching (dph). Fish growth in the G1 and G2 groups was not significantly different from that of the control group ( P>0.05), while fish in the G3 and G4 groups were less active and showed growth depression and high mortality. The gonads of fish in the G3 and G4 groups were smaller and surrounded by hyperplastic connective tissue. The frequency of females in the G0-G4 groups was 54.5%, 75.0%, 100%, 100% and 93.3%, respectively. The RIA analyses of E2 and T showed that T levels decreased during gonadal differentiation, and increased slightly at the onset of ovarian differentiation, while E2 levels increased gradually and peaked at the onset of ovarian differentiation in the control group. In the E2-treated groups, T levels decreased before the onset of ovarian differentiation. E2 levels were high on the 48 dph, but declined to a lower level on the 54 dph, and then increased gradually during gonadal differentiation. And a sharp increase of E2 levels were observed in all E2-treated groups at the onset of ovarian differentiation. The data suggest that T and E2 play important roles during gonadal differentiation, and an E2 dose of 2 mg/kg feed could induce sex reversal in P. olivaceus.

  6. Cytogenetic analysis of two locariid species (Teleostei, Siluriformes) from Iguatemi River (Parana River drainage) in Brazil.

    PubMed

    Fernandes, Carlos Alexandre; Alves, Diandra Soares; Guterres, Zaira da Rosa; Martins-Santos, Isabel Cristina

    2015-01-01

    Fishes of the Loricariidae family, known as "cascudos", constitute an endemic group in Neotropical freshwaters. In this study, were cytogenetically examined two species of Loricariidae (Pterygoplichthysanisitsi Eigenmann & Kennedy, 1903 and Farlowellaamazonum (Gnther, 1864) belonging to Hypostominae and Loricariinae subfamilies respectively) from Iguatemi River. Our study provide the first description regarding C-band and fluorochromic analysis in Farlowellaamazonum. In Farlowellaamazonum, diploid number was 58 chromosomes, with single Ag-NOR and heterochromatic blocks in centromeric regions of some chromosomes and large subtelomeric blocks were evidenced on the long arm of the pair 27, being this region CMA3 (+)/DAPI(-). The Pterygoplichthysanisitsi showed diploid number equal 52 chromosomes, with single Ag-NOR and heterochromatic blocks in centromeric and telomeric regions of some chromosomes and conspicuous large telomeric blocks on the long arm of the pair 10, being this region CMA3 (+)/DAPI(-). The results show that karyotype formula is nonconservative in Pterygoplichthysanisitsi and Farlowellaamazonum. PMID:25893075

  7. Length variation and sequence divergence in mitochondrial control region of Schizothoracine (Teleostei: Cyperinidae) species.

    PubMed

    Syed, Mudasir Ahmad; Bhat, Farooz Ahmad; Balkhi, Masood-Ul Hassan; Bhat, Bilal Ahmad

    2016-03-01

    Schizothoracine fish commonly called snow trouts inhibit the entire network of snow and spring fed cool waters of Kashmir, India. Over 10 species reported earlier, only five species have been found, these include Schizothorax niger, Schizothorax esocinus, Schizothorax plagiostomus, Schizothorax curvifrons and Schizothorax labiatus. The relationship between these species is contradicting. To understand the evolutionary relation of these species, we examined the sequence information of mitochondrial D-loop of 25 individuals representing five species. Sequence alignment showed D-loop region highly variable and length variation was observed in di-nucleotide (TA)n microsatellite between and within species. Interestingly, all these species have (TA)n microsatellite not associated with longer tandem repeats at the 3' end of the mitochondrial control region and do not show heteroplasmy. Our analysis also indicates the presence of four conserved sequence blocks (CSB), CSB-D, CSB-1, CSB-II and CSB-III, four (Termination Associated Sequence) TAS motifs and 15bp pyrimidine block within the mitochondrial control region, that are highly conserved within genus Schizothorax when compared with other species. The phylogenetic analysis carried by Maximum likelihood (ML), Neighbor Joining (NJ) and Bayesian inference (BI) generated almost identical results. The resultant BI tree showed a close genetic relationship of all the five species and supports two distinct grouping of S. esocinus species. Besides the species relation, the presence of length variation in tandem repeats is attributed to differences in predicting the stability of secondary structures. The role of CSBs and TASs, reported so far as main regulatory signals, would explain the conservation of these elements in evolution. PMID:25109626

  8. Sexual Ornaments, Body Morphology, and Swimming Performance in Naturally Hybridizing Swordtails (Teleostei: Xiphophorus)

    PubMed Central

    Johnson, James B.; Macedo, Danielle C.; Passow, Courtney N.; Rosenthal, Gil G.

    2014-01-01

    Determining the costs of sexual ornaments is complicated by the fact that ornaments are often integrated with other, non-sexual traits, making it difficult to dissect the effect of ornaments independent of other aspects of the phenotype. Hybridization can produce reduced phenotypic integration, allowing one to evaluate performance across a broad range of multivariate trait values. Here we assess the relationship between morphology and performance in the swordtails Xiphophorus malinche and X. birchmanni, two naturally-hybridizing fish species that differ extensively in non-sexual as well as sexual traits. We took advantage of novel trait variation in hybrids to determine if sexual ornaments incur a cost in terms of locomotor ability. For both fast-start and endurance swimming, hybrids performed at least as well as the two parental species. The sexually-dimorphic sword did not impair swimming performance per se. Rather, the sword negatively affected performance only when paired with a sub-optimal body shape. Studies seeking to quantify the costs of ornaments should consider that covariance with non-sexual traits may create the spurious appearance of costs. PMID:25329558

  9. Sinocyclocheilus brevifinus (Teleostei: Cyprinidae), a new species of cavefish from Guangxi, China.

    PubMed

    Li, Jie; Li, Xinhui; Mayden, Richard L

    2014-01-01

    Sinocyclocheilus brevifinus sp. nov. is described from a subterranean river at Maohedong Village, Guangxi Zhuang Autonomous Region, Southern China. The new species can be distinguished from all congeners in having functional eyes, last simple dorsal fin ray soft and without serrations along posterior margin, eye diameter small (3.4-5.0 %SL), tip of depressed dorsal fin not reaching vertical at anal fin origin, tip of depressed pelvic fin far from anus, maxillary barbel not reaching anterior edge of operculum, rostral barbel not reaching posterior edge of operculum, scales of lateral line row significantly larger than those of scale rows immediately above and below lateral line, and flanks with distinct black spots and blotches. PMID:25544204

  10. Comparative studies on goby (Teleostei) parasite communities from the North and Baltic Sea.

    PubMed

    Zander, C Dieter

    2005-04-01

    The parasite communities of three goby species from the marine North and the brackish Baltic Sea were compared. The samples of summer 1992/93 from Helgoland, Lubeck and Kiel Bight comprised a parasite spectrum of 4-5 in Pomatoschistus microps, 2-3 in P. pictus or 3-8 parasite species in Gobiusculus flavescens. The highest numbers were found in Kiel Bight whereas those of Helgoland and Lubeck Bight differed between 3 and 7, respectively. In comparing the species identity of the studied localities the value was intermediate in P. microps, low in P. pictus and zero in G. flavescens. Values of prevalence and abundance were clearly lower in Helgoland than in Baltic localities. The prey of Helgoland goby populations comprised meio- and macrobenthos in P. microps, predominantly macrobenthos but also meiobenthos and some plankton in P. pictus, and predominantly plankton and some benthos in G. flavescens. Former studies (Zander in J Zool Syst Evol Res 32:220 1994) revealed a greater variability of prey choice in the Baltic. The greater parasite richness in the Baltic compared with that of Helgoland, may lie on better adaptations of genuine brackish components, lower defence mechanisms of hosts as a consequence of lower salinity, and greater variability in habitat choice. The effect of several filters on the colonisation of parasites in hosts is submitted here in a model. PMID:15772865

  11. The complete mitochondrial genome of small sliver gugeon Squalidus gracilis (Teleostei, Cyprinidae).

    PubMed

    Liu, Guo-Di; Chen, I-Shiung; Zhu, Jun-Quan; Shen, Chia-Ning

    2016-01-01

    In this study, the complete mitogenome sequence of small silver gugeon Squalidus gracilis has been amplified. The mitogenome, consisting of 16,605 base pairs (bp), had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes and a non-coding control region (CR). CR of 928?bp length is located between tRNA(Pro) and tRNA(Phe). The overall base composition of S. gracilis is 29.8% for A, 27.6% for C, 25.7% for T and 16.9% for G, with higher AT content of 55.5%. The complete mitogenome may provide rather essential and important DNA molecular data for further phylogenetic analysis for not only congeneric species but also higher different taxa of Cyprinid fishes. PMID:24749978

  12. Mitochondrial genome of the flat-lip gudgeon, Platysmacheilus exiguus (Teleostei, Cypriniformes).

    PubMed

    Xu, Hao; Xue, Yang; Ye, Qin; Luo, Xi; L, Hong-Jian; Chen, Da-Qing; Li, Yun

    2016-01-01

    The complete mitogenome of an endemic fish in China flat-lip gudgeon, Platysmacheilus exiguous, was determined using the polymerase chain reaction and directly sequenced with the primer walking method. The whole mitogenome was 16,604?bp in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and 1 control region. It had the typical circular molecule structure of vertebrate's mitogenome. The whole base composition was estimated to be 30.77%A, 26.06%T, 26.64%C and 16.53%G with AT bias of 56.83%. The complete mitogenome of P. exiguus provides the fundamental data for conservation genetics study on this species. PMID:24450708

  13. Description of a new species of Hemigrammocapoeta (Teleostei: Cyprinidae) from Lake I??kl?, Turkey.

    PubMed

    Kk, Fahrettin; Bayelebi, Esra; Gl, Salim Serkan; Glle, Iskender

    2015-01-01

    Hemigrammocapoeta menderesensis is distinguished from all other species of Hemigrammocapoeta in Anatolia by the following combination of characters (none unique to the species): lateral line incomplete; 6-17 perforated scales and 36-41 +1-2 scales in lateral series; 7-8 scale rows between lateral line and dorsal-fin origin, 3-4 scale rows between lateral series and anal-fin origin; dorsal fin commonly with 7 branched rays; anal fin with 5 branched rays; 15-17 gill rakers on the first brachial arch; pharyngeal teeth 2.4.5-5.3.3; mouth small, subterminal, horseshoe shaped and without barbel; lips developed and somewhat fleshy; upper lip not covering nostril gape; lower lip with two lateral lobes and median pad; lateral lobes smaller and shorter than half width of median pad; numerous papillae on lower and upper lips. PMID:26701435

  14. The complete mitochondrial genome of Schizothorax prenanti (Tchang) (Teleostei, Cyprinidae, Schizothoracinae).

    PubMed

    Chen, Chun-Na; Huang, Ying-Ying; Li, Hua; Long, Zhi-Hai; Lai, Jian-Sheng; Liu, Guang-Xun; Zhao, Gang

    2016-01-01

    The ya-fish, Schizothorax prenanti, is a well-known commercial cold-water fish species with the hexaploid karyotype distributed in the upper reaches of the Yangtze River and its tributaries on the western Sichuan Plateau in China. The complete mitogenome of S. prenanti is 16,587?bp in length, containing 37 genes of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and a control region (D-loop). The gene nucleotide composition of S. prenanti is 29.6% A, 25.4% T, 27.1% C and 17.9% G, with a slight AT bias of 55.0%. The complete mitogenome sequence of S. prenanti could provide useful data for further studies on genetic structure and diversity, as well as the artificial cultivation and breeding of S. prenanti. PMID:24521499

  15. The complete mitochondrial genome of a cyprinid fish; Metzia longinasus (Teleostei, Cypriniformes).

    PubMed

    Ma, Qinqin; Luo, Wen

    2016-01-01

    The long polymerase chain reaction and primer walking method were applied for the sequencing of the complete mitochondrial genome sequence of a cyprinid species (Metzia longinasus) collected from the Hongshuihe River of the Pearl River drainage, Guangxi Province in China. It is 16,614?bp in length, containing 2 rRNA, 22 tRNA, 13 protein-coding genes and 1 control region generally found in most vertebrates. Most of the mitochondrial genes are encoded on the heavy strand except for eight tRNA and ND6 genes. The base composition of this genome was 31.9% A, 26.2%C, 26.2%T and 15.7%G, showing a lower level of G (15.7%) and a slighter AT bias (58.1%). This is the 2nd completely sequenced mitogenome from genus Metzia. The mtDNA sequence of M. longinasus shared 93% sequence similarity with that of M. formosae and it could contribute to a better solution of its phylogenetic position within cyprinid fishes based on the complete mitogenomic data. PMID:24491097

  16. A new species of torrent catfish, Liobagrus hyeongsanensis (Teleostei: Siluriformes: Amblycipitidae), from Korea.

    PubMed

    Kim, Su-Hwan; Kim, Hyeong-Su; Park, Jong-Young

    2015-01-01

    A new species of torrent catfish, Liobargus hyeongsanensis, is described from rivers and tributaries of the southeastern coast of Korea. The new species can be differentiated from its congeners by the following characteristics: a small size with a maximum standard length (SL) of 90 mm; body and fins entirely brownish-yellow without distinct markings; a relatively short pectoral spine (3.7-6.5 % SL); a reduced body-width at pectoral-fin base (15.5-17.9 % SL); 50-54 caudal-fin rays; 6-8 gill rakers; 2-3 (mostly 3) serrations on pectoral fin; 60-110 eggs per gravid female. PMID:26623807

  17. Phylogeny of moray eels (Anguilliformes: Muraenidae), with a revised classification of true eels (Teleostei: Elopomorpha: Anguilliformes).

    PubMed

    Tang, Kevin L; Fielitz, Christopher

    2013-02-01

    The family Muraenidae is one of the largest and most recognizable eel groups. Moray eels are key components of marine ecosystems but their relationships remain poorly understood. The phylogenetic relationships of the morays are examined herein using mitochondrial 12S and 16S sequence data, totaling 1673bp for 139 taxa. The results of our analyses found support for a monophyletic family Muraenidae that is part of a monophyletic suborder Muraenoidei, which is revised to include the anguilliform families Heterenchelyidae and Myrocongridae, and to exclude the family Chlopsidae. The muraenids form two monophyletic subfamilies, Muraeninae and Uropterygiinae. Of the genera that had multiple species included for analysis, only the type genus of the family, Muraena, is found to be monophyletic. In the subfamily Uropterygiinae, Uropterygius is not recovered as a monophyletic genus. In the subfamily Muraeninae, the species-rich piscivorous genera, Enchelycore and Gymnothorax, and the durophagous genus, Echidna, are demonstrably not monophyletic. The monotypic Gymnomuraena is the sister group to all other muraenine species. The relationships within Muraenidae require much additional study and its genera remain in urgent need of revision. The order Anguilliformes is revised herein to include four suborders: Anguilloidei, Congroidei, Muraenoidei, and Synaphobranchoidei. All four families of the order Saccopharyngiformes are nested within Anguilliformes, recovered as part of a clade that includes Anguillidae; the saccopharyngiform families are referred to the suborder Anguilloidei sensu novum. PMID:22967094

  18. Parasites as biological tags for Eleginops maclovinus (Teleostei: Eleginopidae) around the Falkland Islands.

    PubMed

    Brickle, Paul; Mackenzie, Ken

    2007-06-01

    This is the first study of the parasite fauna of Eleginops maclovinus in the Falkland Islands. It was undertaken to catalogue the parasite fauna of E. maclovinus in order to provide a baseline for future studies and to determine whether parasites might be used as biological tags. Between 21 January and 17 March 2002 samples were taken from three stations, Teal Creek (30 fish), Port Louis (30 fish) and Camilla Creek (10 fish), all in East Falkland, and examined for protozoan and metazoan parasites. Twenty-four parasite taxa were recorded, of which three were possible new species, two new host records and five new geographical records. Because of the small number of fish in the Camilla Creek sample it was excluded from further analyses. E. maclovinus is a protandrous hermaphrodite and all fish greater than 53 cm total length were found to be female, so these too were excluded from further analyses. The parasite data from the remaining fish were analysed by an agglomerative hierarchical cluster analysis using an average linkage and a Jaccard measure of similarity, followed by a linear discriminant function analysis (LDA). Both analyses misclassified only one fish from Port Louis as being from Teal Creek, with the LDA giving an overall correct classification of 97.5% (39/40). The results support mechanical tagging data in suggesting that smaller male E. maclovinus are resident in the creeks in which they are caught, and that at this stage of their lives they tend not to migrate over long distances. PMID:17578595

  19. Schistura andrewi, a new species of loach (Teleostei: Nemacheilidae) from Mizoram, northeastern India.

    PubMed

    Solo, Beihrosa; Lalramliana, Lalramliana; Lalronunga, Samuel; Lalnuntluanga, Lalnuntluanga

    2014-01-01

    Schistura andrewi, a new species of loach, is described from a tributary of Kaladan River in Mizoram, northeastern India. It is distinguished from its congeners in having the following combination of characters: long axillary pelvic lobe; complete lateral line with 82-95 pores; 2 unbranched dorsal and anal fin rays; 6-7 broad, wider than interspace, black bars on the body; 2 rows of black spots horizontally across the dorsal fin; a deeply emarginate caudal fin, with 2 vertical rows of black spots across the fin, and 9 + 8 branched caudal fin rays. PMID:25283204

  20. Osteology of Priocharax and remarkable developmental truncation in a miniature Amazonian fish (Teleostei: Characiformes: Characidae).

    PubMed

    Mattox, George M T; Britz, Ralf; Toledo-Piza, Mônica

    2016-01-01

    Establishing phylogenetic relationships of miniature fishes is challenging in taxa with developmental truncation. Within the Characiformes, developmental truncation appears to be relatively rare, with the Neotropical genus Priocharax being an example. Priocharax includes three miniature species among the smallest of the order and has been hypothesized to belong to the Heterocharacinae. The pronounced reduction in its skeleton, however, prevented a clearer evaluation of its relationships. The present detailed osteological study was designed to address this question and revealed that 21 bones are absent and nine other skeletal structures are simplified in Priocharax when compared to other characids. Comparison of the skeleton of adult Priocharax with early developmental stages of other characids demonstrated that most of the absences and simplifications can be interpreted as developmental truncations. The most striking developmental truncations are in the pectoral girdle, in which the endoskeleton remains entirely cartilaginous. Other interesting truncations are in the ethmoid region of the skull, infraorbital series, and Weberian apparatus, in which the claustrum is absent. Our study also revealed some unusual sexual dimorphisms in the pelvic girdle. Two cladistic analyses were performed to assess the relationships of Priocharax within the Heterocharacinae. The first consisted of a traditional analysis in which all absences and reductions of Priocharax were coded in the same way as in the remaining taxa. This resulted in three equally most parsimonious topologies, all of which have Priocharax as the most basal taxon of the Heterocharacinae. The second analysis incorporated ontogenetic information, and most absences and reductions of Priocharax were reinterpreted as apomorphic conditions and thus, coded differently from similar conditions in outgroups. This resulted in a single phylogenetic hypothesis with Priocharax and Gnathocharax as sister groups based on seven synapomorphies. Our approach demonstrates the importance of developmental studies to better understand morphological evolution of miniaturized, truncated taxa, and to generate hypotheses of their relationships. J. Morphol. 277:65-85, 2016. © 2015 Wiley Periodicals, Inc. PMID:26395188

  1. Fluctuating asymmetry as a pollution monitor: The Australian estuarine smooth toadfish Tetractenos glaber (Teleostei: Tetraodontidae).

    PubMed

    Lajus, Dmitry; Yurtseva, Anastasia; Birch, Gavin; Booth, David J

    2015-12-30

    The relationship between pollution level in estuarine sediment and fluctuating asymmetry (FA) of resident smooth toadfish Tetractenos glaber was evaluated. A total of 188 fish from Sydney and Hawkesbury River estuaries (5 locations from each) were analysed for 28 bilateral skull bone characters. Sediment pollution was quantified based on analysis of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) and organochlorine pesticides (DDT, DDD, DDE, chlordane, dieldrin, lindane). Sediment toxicity was characterized using the mean quotient approach (MERMQ) and ranged from low to moderate level for heavy metals and from low to severe for organochlorides. The mean shape and directional asymmetry of fish bones differed among locations, suggesting a response to local environments. FA was positively correlated with organochlorine pesticides across locations, but not with heavy metals. These results suggest that fish FA could be a useful estimator of stress caused by organic toxicity based on the MERMQ approach. PMID:26443385

  2. Neoniphon pencei, a new species of holocentrid (Teleostei: Beryciformes) from Rarotonga, Cook Islands

    PubMed Central

    Pyle, Richard L.; Earle, John L.

    2015-01-01

    Abstract Neoniphon pencei, n. sp., is described from thirteen specimens, 132-197 mm standard length (SL) collected from mesophotic coral ecosystems (MCEs) at Rarotonga, Cook Islands by divers using mixed-gas closed-circuit rebreathers. It differs from all other species of the genus in number of lateral line scales, scales above and below lateral line, elements of life color, and in COI and cytochrome b DNA sequences. Of the five other known species of Neoniphon, it is most similar to the Indo-Pacific N. aurolineatus and the western Atlantic N. marianus both morphologically and genetically. PMID:25698898

  3. The structure and ultrastructure of the rostral cartilage in the spiny eel, Macrognathus siamensis (Teleostei: Mastacembeloidei).

    PubMed

    Benjamin, M; Sandhu, J S

    1990-04-01

    An elastic, cell-rich cartilage provides flexible support to the highly mobile, rostral tentacle of the mastacembelid, Macrognathus siamensis. Active movement of the tentacle is effected by skeletal muscles, the muscular bellies of which are located outside the organ. The tentacle returns to its original shape by elastic recoil. The cartilage resembles plant supporting tissue and the cartilages of certain invertebrates. It is surrounded by a thick perichondrium and articulates at a synovial joint with the supraethmoid. The chondrocytes are large and shrunken within lacunae. They contain glycogen and cytoplasmic stores of RNA. The matrix is reduced to thin seams between adjacent cells, and stains strongly with alcian blue and a variety of elastic stains. Parts of the matrix are trilaminar, and such an appearance recalls the distinction between the primary cell walls of adjacent plant cells and the intervening middle lamella. The perichondrium consists of an alternating sequence of cells, circularly arranged collagen fibres and a foamy, amorphous material of unknown composition. Deep to the perichondrium, the chondrocytes are packed with intermediate filaments. Membrane-bound organelles are not prominent, though mitochondria are located at the periphery of the cell. The ultrastructural similarities between these chondrocytes and those of hyaline-cell cartilage (chondroid) support the contention that Schaffer's concept of a rigid distinction between 'true' cartilage and 'chondroid' is no longer tenable. The matrix is devoid of collagen and is most distinctive. In the immediate vicinity of the cells it consists of matrix granules and matrix fibers but, where a trilaminar appearance is easily discernible, there is a central zone that consists of large masses of amorphous material that is presumed to contain elastin. Such amorphous material has not previously been seen in any teleostean elastic tissue. By contrast, elastic system fibres, readily demonstrable elsewhere in teleosts, are conspicuously absent. PMID:1696572

  4. Saurenchelys gigas sp. nov., a new nettastomatid eel (Teleostei, Anguilliformes, Nettastomatidae) from the western central Pacific.

    PubMed

    Lin, James; Smith, David G; Shao, Kwang-Tsao; Chen, Hong-Ming

    2015-01-01

    Some large Saurenchelys specimens collected from Daxi, Yilan, NE Taiwan, and Da Nang, Vietnam, by bottom trawl at depths of 100-200 m, are described as Saurenchelys gigas new species. They differ from all known adult Saurenchelys species by predorsal length 40.9-46.8, head length 36.8-39.3in % of preanal length, 38-40 preanal vertebrae, 63-70 precaudal vertebrae, 38-42 preanal lateral-line pores, 56-63 preanal dorsal fin rays, and larger size (the maximum size 1155 mm TL). PMID:26701596

  5. Cryptic diversity and venom glands in Western atlantic clingfishes of the genus acyrtus (Teleostei: Gobiesocidae).

    PubMed

    Conway, Kevin W; Baldwin, Carole; White, Macaulay D

    2014-01-01

    Examination of genetic data (mitochondrial cytochrome c oxidase I) for western Atlantic clingfishes revealed two distinct lineages within a group of individuals originally identified as Acyrtus artius. Subsequent investigation of preserved voucher specimens was conducted to reconcile the genetic data and the existing classification, which is based on morphology. In addition to discovering that one of the genetic lineages is an undescribed species, which we describe as Acyrtus lanthanum, new species, we found that the nominal species Acyrtus artius has a putative venom gland associated with the subopercle that has been overlooked since the species was described nearly 60 years ago. The new species lacks the subopercular gland as does Acyrtus rubiginosus, but one is present in the related Arcos nudus. Venom glands have not been reported previously for the Gobiesocidae, and the venom gland described herein for Acyrtus and Arcos represents the first example in teleost fishes of a venom gland associated with the subopercle. PMID:24825326

  6. Kudoa inornata sp. n. (Myxosporea: Multivalvulida) from the skeletal muscles of Cynoscion nebulosus (Teleostei: Sciaenidae).

    PubMed

    Dykov, Iva; de Buron, Isaure; Fiala, Ivan; Roumillat, William A

    2009-06-01

    A new myxosporean species, Kudoa inornata sp. n. (Myxosporea: Multivalvulida), is described from skeletal muscles of the spotted seatrout Cynoscion nebulosus (Cuvier), collected in estuarine waters along the coast of South Carolina, USA. Light microscopic and ultrastructural characters rank this species to the group of Kudoa species with simple-shaped spores. The uniqueness of the SSU and LSU rDNA sequences justifies its status of a new species with sister relationship to Kudoa paniformis. The 100% prevalence in seatrout from four out of five localities sampled and pathogenicity of K. inornata recognized in this study should motivate further screening for infections in its host, which is considered a commercially important game fish with a wide distribution in the Western North Atlantic. PMID:19606785

  7. Evolution of ontogenetic dietary shifts and associated gut features in prickleback fishes (Teleostei: Stichaeidae).

    PubMed

    German, D P; Gawlicka, A K; Horn, M H

    2014-02-01

    We tested the hypothesis that an ontogenetic dietary shift from carnivory to herbivory or omnivory, and concomitant changes in the gut facilitating digestion of algae, are synapomorphies of the tribes Xiphisterini and Esselenichthyini in the family Stichaeidae (pricklebacks). Previous investigations have revealed that two xiphisterine pricklebacks-Xiphister mucosus and Xiphister atropurpureus-become herbivorous or omnivorous, respectively, as their bodies grow larger, and that their guts show related changes in length and function. In this study we found that, with increase in size, the basal member of the Xiphisterini, Phytichthys chirus, showed an increased proportion of algae in its diet, increased activity of α-amylase and decreased activity of aminopeptidase, all of which support the synapomorphy hypothesis. Cebidichthys violaceus, a herbivore in the Esselenichthyini, shows similar ontogenetic changes in diet and digestive tract length and physiology, but these features were not observed in two derived carnivores, Dictyosoma burgeri and Dictyosoma rubrimaculatum, within the clade. These results suggest that herbivory is isolated to C. violaceus within the Esselenichthyini. Allometric relationships of gut length as a function of body size generally follow diet within the Xiphisterini and Esselenichthyini, with herbivores having the longest guts, which become disproportionately longer than body size as the fishes grow, omnivores intermediate gut lengths, and carnivores the shortest. A carnivore from an adjacent clade, Anoplarchus purpurescens, had the shortest gut, which did not change in length relative to body length as the fish grew. Overall, our results clarify the patterns of dietary evolution within the Stichaeidae and lay the foundation for more detailed studies of dietary and digestive specialization in fishes in the family. PMID:24269211

  8. Descriptions of three new species of Marcusenius Gill, 1862 (Teleostei: Mormyridae) from South Africa and Mozambique.

    PubMed

    Maake, Pholoshi A; Gon, Ofer; Swartz, Ernst R

    2014-01-01

    Morphological and genetic studies of mormyrid fishes belonging to the genus Marcusenius from South Africa and Mozambique revealed four species of which three are described as new. Marcusenius pongolensis is widespread throughout the Incomati, Pongola and Kosi river systems, and sparsely represented in the Limpopo River system in South Africa. Marcusenius krameri sp. nov. is endemic to the Limpopo River system, and is the sister taxon of M. caudisquamatus sp. nov. from the Nseleni and Mhlatuze river systems in the KwaZulu-Natal Province of South Africa. The Ruvuma specimens were well differentiated from all southern and eastern African species of Marcusenius, and are therefore recognised as M. lucombesi sp. nov. Phylogenetic analysis of the mitochondrial cytochrome b gene showed that the three new species and M. altisambesi form a monophyletic lineage that is sister to a group containing M. pongolensis and M. macrolepidotus. Marcusenius krameri and M. lucombesi seems to prefer slow flowing reaches of rivers, whereas M. pongolensis and M. caudisquamatus seems to mainly inhabit rapid flowing sections of rivers with a rocky substrate. A key to the southern African species of Marcusenius is provided. PMID:24871846

  9. Functional analysis of a specialized prey processing behavior: winnowing by surfperches (Teleostei: Embiotocidae).

    PubMed

    Drucker, E G; Jensen, J S

    1991-12-01

    Several surfperches (Embiotocidae), including the black surfperch, Embiotoca jacksoni, exhibit a specialized prey handling behavior known as winnowing, in which ingested food and non-nutritive debris are separated within the oropharyngeal cavity. Prey items are swallowed, and unpalatable material is ejected from the mouth. Winnowing is believed to play an important role in the partitioning of food resources among sympatric embiotocids. We present a mechanistic model for this separative prey processing based on high-speed video analysis, cineradiography, electromyography, and buccal and opercular cavity pressure transducer recording. Winnowing by embiotocids is characterized by premaxillary protrusions repeated cyclically with reduced oral gape. Protrusion is accompanied by depression of the hyoid apparatus and adduction of the opercula. Alternating expansion and contraction of the buccal and opercular cavities generate regular pressure waveforms that indicate bidirectional water flow during processing. Separation of food from debris by Embiotoca jacksoni occurs in three phases. The prey-debris bolus is transported anteriorly and posteriorly within the oropharyngeal cavity and is then sheared by the pharyngeal jaws. Mechanical processing is complemented by the rinsing action of water currents during hydraulic prey transport. The feeding apparatus of Embiotoca jacksoni is functionally versatile, although not obviously specialized relative to that of nonwinnowing surfperches. Protrusion of the premaxillae and depression of the hyoid apparatus are critical to both prey capture and subsequent prey processing. The pharyngeal jaws exhibit kinematic patterns during separation of food from debris distinct from those observed during mastication of uncontaminated prey. This behavioral flexibility facilitates resource partitioning and the coexistence of E. jacksoni in sympatric embiotocid assemblages. PMID:1791628

  10. A new marine gobiid species of the genus Clariger Jordan & Snyder (Gobiidae, Teleostei) from Taiwan.

    PubMed

    Jang-Liaw, Nian-Hong; Gong, You-Hai; Chen, I-Shiung

    2012-01-01

    A new species of Clariger Jordan & Snyder, 1901 was collected from northern Taiwan. The genus was previously known only from Japanese waters. This discovery is the first formal and southernmost record of these marine gobies from the waters of subtropical Taiwan. The new species, Clariger taiwanensissp. n., is distinguished from its congeners by a unique combination of features: (1) fin rays: dorsal-fin rays III, I/8; anal-fin rays modally I/8; and pectoral-fin rays modally 19 (2+16+1); (2) longitudinal dermal ridge on head with 6 barbels; and (3) specific coloration pattern: head and trunk dark brown with scattered pale spots and blotches; cheek, ventral portion of head sometimes pale with deep brown spots; pectoral-fin base with a dark brown band; and caudal fin mostly dark brown proximally and with alternating and irregular dark brown and pale bands distally. A diagnostic key to all nominal species from Japan and Taiwan is provided. PMID:22711994

  11. Mitogenomic Evidence for an Indo-West Pacific Origin of the Clupeoidei (Teleostei: Clupeiformes)

    PubMed Central

    Lavoué, Sébastien; Miya, Masaki; Musikasinthorn, Prachya; Chen, Wei-Jen; Nishida, Mutsumi

    2013-01-01

    The clupeoid fishes are distributed worldwide, with marine, freshwater and euryhaline species living in either tropical or temperate environments. Regional endemism is important at the species and genus levels, and the highest species diversity is found in the tropical marine Indo-West Pacific region. The clupeoid distribution follows two general pattern of species richness, the longitudinal and latitudinal gradients. To test historical hypotheses explaining the formation of these two gradients, we have examined the early biogeography of the Clupeoidei in reconstructing the evolution of their habitat preferences along with their ancestral range distributions on a time-calibrated mitogenomic phylogeny. The phylogenetic results support the distinction of nine main lineages within the Clupeoidei, five of them new. We infer several independent transitions from a marine to freshwater environment and from a tropical to temperate environment that occurred after the initial diversification period of the Clupeoidei. These results combined with our ancestral range reconstruction hypothesis suggest that the probable region of origin and diversification of the Clupeoidei during the Cretaceous period was the tropical marine precursor to the present Indo-West Pacific region. Thus, our study favors the hypotheses of “Region of origin” and “Tropical conservatism” to explain the origins of the longitudinal and latitudinal gradients of clupeoid species richness, respectively. Additional geological and paleontological evidence further define the tropical marine paleo-region of origin as the eastern Tethys Sea region. The Cretaceous fossil record of the Clupeoidei is partially incongruent with the results here as it contains taxa found outside this region. We discuss three possible causes of conflict between our biogeographical hypothesis and the distributions of the Cretaceous clupeoid fossils: regional extinction, incomplete taxonomic sampling and incorrect timescale estimation. PMID:23431379

  12. Genetic Linkage Map of Fishes of the Genus Xiphophorus (Teleostei: Poeciliidae)

    PubMed Central

    Morizot, D. C.; Slaugenhaupt, S. A.; Kallman, K. D.; Chakravarti, A.

    1991-01-01

    Analysis of genotypes of 76 polymorphic loci in more than 2600 backcross hybrid individuals derived from intra- and interspecific genetic crosses of fishes of the genus Xiphophorus (Poeciliidae) resulted in the identification of 17 multipoint linkage groups containing 55 protein-coding loci and one sex chromosome-linked pigment pattern gene. Multipoint linkage analyses identified highly probable gene orders for 10 linkage groups. The total genome length was estimated to be ~18 Morgans. Comparisons of the Xiphophorus linkage map with those of other fishes, amphibians and mammals suggested that fish gene maps are remarkably similar and probably retain many syntenic groups present in the ancestor of all vertebrates. PMID:2004711

  13. The complete mitochondrial genome sequence of Triplophysa anterodorsalis (Teleostei, Balitoridae, Nemacheilinae).

    PubMed

    Que, Yan-Fu; Liao, Xiao-Lin; Xu, Dong-Mei; Yang, Zhi; Tang, Hui-Yuan; Zhu, Bin

    2016-03-01

    Triplophysa anterodorsalis is an endemic fish in the upper stream of the Yangtze River, Jinsha River and its tributaries. However, wild populations of T. anterodorsalis declined sharply due to cascade hydropower stations constructed successively in the Jinsha River during the past decades. In the present study, the complete mitochondrial DNA genome sequence of T. anterodorsalis was first determined by DNA sequencing based on the PCR fragments. The complete mitochondrial genome sequence of T. anterodorsalis is a circular molecule of 16,567?bp in size. It consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a control region (D-loop). The gene nucleotide composition of T. anterodorsalis is 27.37% A, 25.68% C, 18.37% G, and 28.57% T, with a relatively a relatively high A?+?T content (55.94%). The results could provide useful data for studies on genetic structure and diversity and rational resource conservation in T. anterodorsalis. PMID:24919506

  14. Mercury in the biotic compartments of Northwest Patagonia lakes, Argentina.

    PubMed

    Rizzo, A; Arcagni, M; Arribére, M A; Bubach, D; Guevara, S Ribeiro

    2011-06-01

    We report on total mercury (THg) concentrations in the principal components of food webs of selected Northern Patagonia Andean Range ultraoligotrophic lakes, Argentina. The THg contents were determined using Instrumental Neutron Activation Analysis in muscle and liver of four fish species occupying the higher trophic positions (the introduced Salmo trutta, Oncorhynchus mykiss and Salvelinus fontinalis, and the native Percichthys trucha) accounted for eight lakes belonging to Nahuel Huapi and Los Alerces National Parks. We studied the food web components of both the West and East branches of Lake Moreno, including benthic primary producers such as biofilm, mosses, and macrophytes, three plankton fractions, fish, riparian tree leaves, and benthic invertebrates, namely decapods, molluscs, insect larvae, leeches, oligochaetes, and amphipods. Mercury concentrations in fish muscle varied in a wide range, from less than 0.05 to 4 μg g(-1) dry weight (DW), without a distribution pattern among species but showing higher values for P. trucha and S. fontinalis, particularly in Lake Moreno. The THg contents of the food web components of Lake Moreno varied within 4 orders of magnitude, with the lower values ranging from 0.01 to 0.5 μg g(-1) DW in tree leaves, some macrophytes, juvenile salmonids or benthic macroinvertebrates, and reaching concentrations over 200 μg g(-1) DW in the plankton. Juvenile Galaxias maculatus caught in the pelagic area presented the highest THg contents of all fish sampled, reaching 10 μg g(-1) DW, contents that could be associated with the high THg concentrations in plankton since it is their main food source. Although Lake Moreno is a system without local point sources of contamination, situated in a protected area, some benthic organisms presented high THg contents when compared with those from polluted ecosystems. PMID:21421254

  15. Separating natural responses from experimental artefacts: habitat selection by a diadromous fish species using odours from conspecifics and natural stream water.

    PubMed

    Hale, Robin; Swearer, Stephen E; Downes, Barbara J

    2009-03-01

    Animals use sensory stimuli to assess and select habitats, mates and food as well as to communicate with other individuals. One way they do this is to use olfaction, whereby they identify and respond to chemical cues. All organisms release odours, which mix with other chemical substances and ambient environmental conditions. The result is that animals are frequently immersed in a complex, highly dynamic sensory environment where they must identify and respond to only some of the potential stimuli they encounter in the face of significant levels of background noise. Understanding how organisms respond to different chemical cues is therefore dependent on knowing how these responses might be influenced by potential interactions with other stimuli. To test this, we examined whether the diadromous fish Galaxias maculatus was attracted to conspecific odours and whether this response differed when cues were offered in an artificial environment lacking other potential chemical stimuli (tap water) or a more natural background environment (stream water). We found that (1) fish responded to both natural stream water odours and those from conspecifics but the response to the latter was stronger; (2) the attraction to conspecific odours was stronger in tap water than in stream water, which indicates the importance of these odours may be overestimated when they are offered in artificial media. We also conducted a brief literature review, which confirmed that artificial media are commonly used in experiments and that the background environment is often not considered. Our results show that future research testing the responses of organisms to auditory, olfactory and visual cues should carefully consider the context in which cues are presented. Without doing so, such studies may inaccurately assess the importance of sensory cues in natural situations in the wild. PMID:19139923

  16. Population sinks resulting from degraded habitats of an obligate life-history pathway.

    PubMed

    Hickford, Michael J H; Schiel, David R

    2011-05-01

    Many species traverse multiple habitats across ecosystems to complete their life histories. Degradation of critical, life stage-specific habitats can therefore lead to population bottlenecks and demographic deficits in sub-populations. The riparian zone of waterways is one of the most impacted areas of the coastal zone because of urbanisation, deforestation, farming and livestock grazing. We hypothesised that sink populations can result from alterations of habitats critical to the early life stages of diadromous fish that use this zone, and tested this with field-based sampling and experiments. We found that for Galaxias maculatus, one of the most widely distributed fishes of the southern hemisphere, obligate riparian spawning habitat was very limited and highly vulnerable to disturbance across 14 rivers in New Zealand. Eggs were laid only during spring tides, in the highest tidally influenced vegetation of waterways. Egg survival increased to >90% when laid in three riparian plant species and where stem densities were great enough to prevent desiccation, compared to no survival where vegetation was comprised of other species or was less dense. Experimental exclusion of livestock, one of the major sources of riparian degradation in rural waterways, resulted in quick regeneration, a tenfold increase in egg laying by fish and a threefold increase in survival, compared to adjacent controls. Overall, there was an inverse relationship between river size and egg production. Some of the largest rivers had little or no spawning habitat and very little egg production, effectively becoming sink populations despite supporting large adult populations, whereas some of the smallest pristine streams produced millions of eggs. We demonstrate that even a wide-ranging species with many robust adult populations can be compromised if a stage-specific habitat required to complete a life history is degraded by localised or more diffuse impacts. PMID:21076966

  17. Synergistic Interactions within Disturbed Habitats between Temperature, Relative Humidity and UVB Radiation on Egg Survival in a Diadromous Fish

    PubMed Central

    Hickford, Michael J. H.; Schiel, David R.

    2011-01-01

    Anthropogenic impacts, including urbanization, deforestation, farming, and livestock grazing have altered riparian margins worldwide. One effect of changes to riparian vegetation is that the ground-level light, temperature, and humidity environment has also been altered. Galaxias maculatus, one of the most widely distributed fishes of the southern hemisphere, lays eggs almost exclusively beneath riparian vegetation in tidally influenced reaches of rivers. We hypothesized that the survival of these eggs is greatly affected by the micro-environment afforded by vegetation, particularly relating to temperature, humidity and UVB radiation. We experimentally reduced riparian vegetation height and altered shading characteristics, tracked egg survival, and used small ground-level temperature, humidity and UVB sensors to relate survival to ground-level effects around egg masses. The ground-level physical environment was markedly different from the surrounding ambient conditions. Tall dense riparian vegetation modified ambient conditions to produce a buffered temperature regime with constant high relative humidity, generally above 90%, and negligible UVB radiation at ground-level. Where vegetation height was reduced, frequent high temperatures, low humidity, and high UVB irradiances reduced egg survival by up to 95%. Temperature effects on egg survival were probably indirect, through reduced humidity, because developing eggs are known to survive in a wide range of temperatures. In this study, it was remarkable how such small variations in relatively small sites could have such a large effect on egg survival. It appears that modifications to riparian vegetation and the associated changes in the physical conditions of egg laying sites are major mechanisms affecting egg survival. The impacts associated with vegetational changes through human-induced disturbances are complex yet potentially devastating. These effects are particularly important because they affect a very small portion of habitat that is required to complete the life history of a species, despite the wide distribution of adults and juveniles across aquatic and marine environments. PMID:21931680

  18. Modeling prey consumption by native and non-native piscivorous fishes: implications for competition and impacts on shared prey in an ultraoligotrophic lake in Patagonia

    USGS Publications Warehouse

    Juncos, Romina; Beauchamp, David A.; Viglianoc, Pablo H.

    2013-01-01

    We examined trophic interactions of the nonnative salmonids Rainbow Trout Oncorhynchus mykiss, Brown Trout Salmo trutta, and Brook Trout Salvelinus fontinalisand the main native predator Creole Perch Percichthys trucha in Lake Nahuel Huapi (Patagonia, Argentina) to determine the relative impact of each predator on their forage base and to evaluate the potential vulnerability of each predator to competitive impacts by the others. Using bioenergetics simulations, we demonstrated the overall importance of galaxiids and decapods to the energy budgets of nonnative salmonids and Creole Perch. Introduced salmonids, especially Rainbow Trout, exerted considerably heavier predatory demands on shared resources than did the native Creole Perch on both a per capita basis and in terms of relative population impacts. Rainbow Trout consumed higher quantities and a wider size range of Small Puyen (also known as Inanga) Galaxias maculatus than the other predators, including early pelagic life stages of that prey; as such, this represents an additional source of mortality for the vulnerable early life stages of Small Puyen before and during their transition from pelagic to benthic habitats. All predators were generally feeding at high feeding rates (above 40% of their maximum physiological rates), suggesting that competition for prey does not currently limit either Creole Perch or the salmonids in this lake. This study highlights the importance of keystone prey for the coexistence of native species with nonnative top predators. It provides new quantitative and qualitative evidence of the high predation pressure exerted on Small Puyen, the keystone prey species, during the larval to juvenile transition from pelagic to littoral-benthic habitat in Patagonian lakes. This study also emphasizes the importance of monitoring salmonid and Creole Perch population dynamics in order to detect signs of potential impacts through competition and shows the need to carefully consider the rationale behind any additional trout stocking.

  19. Goblet Cells and Mucus Types in the Digestive Intestine and Respiratory Intestine in Bronze Corydoras (Callichthyidae: Teleostei).

    PubMed

    Leknes, I L

    2015-10-01

    The structure and histochemical properties of the intestine in bronze corydoras (Corydoras aeneus), a stomach-containing teleost, are described, with emphasis on goblet cells and mucin types. The proximal intestine displayed a normal structure for teleosts, whereas the distal intestine was wide, translucent, thin-walled, richly vascularized and constantly filled with air, suggesting an important respiratory role. Goblet cells were common throughout the entire intestine and displayed a variable, but mainly faint metachromatic colour after toluidine blue. They were moderately coloured by alcian blue at both pH 2.5 and 0.2 and displayed no colour after periodic acid followed by Schiff's solution (PAS), but a distinct purple-brown colour after high iron diamine followed by alcian blue (pH 2.5). Together, these results suggest that the mucin in the intestine goblet cells consists mainly of sulphated proteoglycans. Further, the results from the present lectin and neuraminidase tests suggest that these mucins contain much N-acetylglucoseamines and some N-acetylgalactosamines and sialic acid, but seem to lack glucose and mannose. They also contain some galactose-N-acetylgalactosamines sequences, normally hidden by sialic acid. The distinct brush border and mucus layer on the epithelial cells in the respiratory intestine may indicate some digestive roles, such as absorption of water, ions and simple carbohydrates. As sulphated proteoglycans are tough and attract much water, this mucus may play important roles in the protection against mechanical and chemical damages and in the defence against micro-organisms throughout the entire intestine, but in the respiratory intestine it may impede significantly the oxygen uptake. However, as this part of the intestine usually contains no digesta, but is completely filled with air, frequently renewed by dry air from the atmosphere, and the main function of the mucus may be to protect the respiratory epithelium against a destroying and dangerous desiccation. PMID:25142839

  20. Phylogenetic relationships within the speciose family Characidae (Teleostei: Ostariophysi: Characiformes) based on multilocus analysis and extensive ingroup sampling

    PubMed Central

    2011-01-01

    Background With nearly 1,100 species, the fish family Characidae represents more than half of the species of Characiformes, and is a key component of Neotropical freshwater ecosystems. The composition, phylogeny, and classification of Characidae is currently uncertain, despite significant efforts based on analysis of morphological and molecular data. No consensus about the monophyly of this group or its position within the order Characiformes has been reached, challenged by the fact that many key studies to date have non-overlapping taxonomic representation and focus only on subsets of this diversity. Results In the present study we propose a new definition of the family Characidae and a hypothesis of relationships for the Characiformes based on phylogenetic analysis of DNA sequences of two mitochondrial and three nuclear genes (4,680 base pairs). The sequences were obtained from 211 samples representing 166 genera distributed among all 18 recognized families in the order Characiformes, all 14 recognized subfamilies in the Characidae, plus 56 of the genera so far considered incertae sedis in the Characidae. The phylogeny obtained is robust, with most lineages significantly supported by posterior probabilities in Bayesian analysis, and high bootstrap values from maximum likelihood and parsimony analyses. Conclusion A monophyletic assemblage strongly supported in all our phylogenetic analysis is herein defined as the Characidae and includes the characiform species lacking a supraorbital bone and with a derived position of the emergence of the hyoid artery from the anterior ceratohyal. To recognize this and several other monophyletic groups within characiforms we propose changes in the limits of several families to facilitate future studies in the Characiformes and particularly the Characidae. This work presents a new phylogenetic framework for a speciose and morphologically diverse group of freshwater fishes of significant ecological and evolutionary importance across the Neotropics and portions of Africa. PMID:21943181

  1. Molecular phylogeny of grunts (Teleostei, Haemulidae), with an emphasis on the ecology, evolution, and speciation history of New World species

    PubMed Central

    2012-01-01

    Background The fish family Haemulidae is divided in two subfamilies, Haemulinae and Plectorhynchinae (sweetlips), including approximately 17 genera and 145 species. The family has a broad geographic distribution that encompasses contrasting ecological habitats resulting in a unique potential for evolutionary hypotheses testing. In the present work we have examined the phylogenetic relationships of the family using selected representatives of additional Percomorpha based on Bayesian and Maximum likelihood methods by means of three mitochondrial genes. We also developed a phylogenetic hypothesis of the New World species based on five molecular markers (three mitochondrial and two nuclear) as a framework to evaluate the evolutionary history, the ecological diversification and speciation patterns of this group. Results Mitochondrial genes and different reconstruction methods consistently recovered a monophyletic Haemulidae with the Sillaginidae as its sister clade (although with low support values). Previous studies proposed different relationships that were not recovered in this analysis. We also present a robust molecular phylogeny of Haemulinae based on the combined data of two nuclear and three mitochondrial genes. All topologies support the monophyly of both sub-families (Haemulinae, Plectorhinchinae). The genus Pomadasys was shown to be polyphyletic and Haemulon, Anisotremus, and Plectorhinchus were found to be paraphyletic. Four of seven presumed geminate pairs were indeed found to be sister species, however our data did not support a contemporaneous divergence. Analyses also revealed that differential use of habitat might have played an important role in the speciation dynamics of this group of fishes, in particular among New World species where extensive sample coverage was available. Conclusions This study provides a new hypothesis for the sister clade of Hamulidae and a robust phylogeny of the latter. The presence of para- and polyphyletic genera underscores the need for a taxonomic reassessment within the family. A scarce sampling of the Old World Pomadasys species prevents us to definitively point to a New World origin of the sub-familiy Hamulinae, however our data suggest that this is likely to be the case. This study also illustrates how life history habitat influences speciation and evolutionary trajectories. PMID:22537107

  2. Taxonomical and morphological notes on two species of mudskippers, Periophthalmus walailakae and Periophthalmodon schlosseri (Teleostei: Gobiidae) from Singapore.

    PubMed

    Jaafar, Zeehan; Lim, Kelvin K P; Chou, Loke Ming

    2006-11-01

    The mudskipper Periophthalmus walailakae is recorded from Singapore, where it was previously misidentified as Periophthalmodon schlosseri, with which it is syntopic. Periophthalmus walailakae is distinguished from its congeners by the following combination of characters: pelvic fins completely united and shaped like a disk, and first dorsal fin dark brown or black, with a rounded posterior edge and a white distal margin. This species most closely resembles Pn. schlosseri but has one row of teeth on the upper jaw, scales on the isthmus, and a different upper lip and jaw morphology. Contrary to an earlier report, scales are present on the snout, interorbital, and isthmus of Ps. walailakae. The two species can also be distinguished by size, external morphology, and body color patterns. PMID:17189918

  3. [Histology of the ovary of Macrodon ancylodon (Bloch and Schneider, 1801) Teleostei: Sciaenidae). Oogenesis. Post-ovulatory follicles. Atresia].

    PubMed

    Vizziano, D; Berois, N

    1990-05-01

    The reproductive cycle of Teleostean fishes may be studied from different points of view. One of them is to examine the histological changes that take place in the gonad. A histological description of the gonad is to be done first. In this work we have studied the oogenesis, atresia and post-ovulatory follicles of Macrodon ancylodon. Specimens were collected from April 1982 to May 1983 on the coast of Ro de la Plata (Montevideo, Uruguay). Material used was preserved in neutralized 10% formalin inbedded in paraffin and paraffin-celloidin, sectioned at 5 - 10 microns and stained with haematoxilin-eosin. Pas-haematoxilin, and specific techniques for lipid detection were used. Six oogenetic stages were recognized: oogonias, and basophilic, lipid yolk vesicles, protein yolk vesicles, matures and ripe hydrated oocytes. Theca and granulosa are negative to lipid and cholesterol histochemic reaction techniques. Post-ovulatory follicles show structural degenerative changes. Two types of atresia are described: hypertrophic and nonhypertrophic, which apparently would not have an endocrine function. It is important to recognize post-ovulatory follicles to establish the spawning pattern and also to recognize atretic follicles due to their incidence in the fecundity of a species. PMID:2089488

  4. Concerted Evolution of Duplicate Control Regions in the Mitochondria of Species of the Flatfish Family Bothidae (Teleostei: Pleuronectiformes)

    PubMed Central

    Munroe, Thomas A.; Gong, Li; Kong, Xiao-Yu

    2015-01-01

    Mitogenomes of flatfishes (Pleuronectiformes) exhibit the greatest diversity of gene rear-rangements in teleostean fishes. Duplicate control regions (CRs) have been found in the mito-genomes of two flatfishes, Samariscus latus (Samaridae) and Laeops lanceolata (Bothidae), which is rare in teleosts. It has been reported that duplicate CRs have evolved in a concerted fashion in fishes and other animals, however, whether concerted evo-lution exists in flatfishes remains unknown. In this study, based on five newly sequenced and six previously reported mitogenomes of lefteye flounders in the Bothidae, we explored whether duplicate CRs and concerted evolution exist in these species. Results based on the present study and previous reports show that four out of eleven bothid species examined have duplicate CRs of their mitogenomes. The core regions of the duplicate CRs of mitogenomes in the same species have identical, or nearly identical, sequences when compared to each other. This pattern fits the typical characteristics of concerted evolution. Additionally, phylogenetic and ancestral state reconstruction analysis also provided evidence to support the hypothesis that duplicate CRs evolved concertedly. The core region of concerted evolution is situated at the conserved domains of the CR of the mitogenome from the termination associated sequences (TASs) to the conserved sequence blocks (CSBs). Commonly, this region is con-sidered to regulate mitochondrial replication and transcription. Thus, we hypothesize that the cause of concerted evolution of the duplicate CRs in the mtDNAs of these four bothids may be related to some function of the conserved sequences of the CRs during mitochondrial rep-lication and transcription. We hope our results will provide fresh insight into the molecular mechanisms related to replication and evolution of mitogenomes. PMID:26237419

  5. Concerted Evolution of Duplicate Control Regions in the Mitochondria of Species of the Flatfish Family Bothidae (Teleostei: Pleuronectiformes).

    PubMed

    Li, Dong-He; Shi, Wei; Munroe, Thomas A; Gong, Li; Kong, Xiao-Yu

    2015-01-01

    Mitogenomes of flatfishes (Pleuronectiformes) exhibit the greatest diversity of gene rear-rangements in teleostean fishes. Duplicate control regions (CRs) have been found in the mito-genomes of two flatfishes, Samariscus latus (Samaridae) and Laeops lanceolata (Bothidae), which is rare in teleosts. It has been reported that duplicate CRs have evolved in a concerted fashion in fishes and other animals, however, whether concerted evo-lution exists in flatfishes remains unknown. In this study, based on five newly sequenced and six previously reported mitogenomes of lefteye flounders in the Bothidae, we explored whether duplicate CRs and concerted evolution exist in these species. Results based on the present study and previous reports show that four out of eleven bothid species examined have duplicate CRs of their mitogenomes. The core regions of the duplicate CRs of mitogenomes in the same species have identical, or nearly identical, sequences when compared to each other. This pattern fits the typical characteristics of concerted evolution. Additionally, phylogenetic and ancestral state reconstruction analysis also provided evidence to support the hypothesis that duplicate CRs evolved concertedly. The core region of concerted evolution is situated at the conserved domains of the CR of the mitogenome from the termination associated sequences (TASs) to the conserved sequence blocks (CSBs). Commonly, this region is con-sidered to regulate mitochondrial replication and transcription. Thus, we hypothesize that the cause of concerted evolution of the duplicate CRs in the mtDNAs of these four bothids may be related to some function of the conserved sequences of the CRs during mitochondrial rep-lication and transcription. We hope our results will provide fresh insight into the molecular mechanisms related to replication and evolution of mitogenomes. PMID:26237419

  6. Embryonic and larval developmental stages of African giant catfish Heterobranchus bidorsalis (Geoffroy Saint Hilaire, 1809) (Teleostei, Clariidae).

    PubMed

    Olaniyi, Wasiu Adekunle; Omitogun, Ofelia Galman

    2014-01-01

    The dearth of African giant catfish Heterobranchus bidorsalis seeds poses great threat to its aquaculture and biodiversity, hence detailed knowledge and understanding of its embryology is indispensable for its artificial propagation and conservation programmes. Photomicrographs of extruded oocyte through all developmental cell stages of live embryo to larval stage are documented with the aid of a light microscope. The optical transparency of the developing embryo enabled us to describe its deep structures, distinctive features and characterize the stages pictorially. Extruded oocyte had a mean diameter of 1??0.1mm, ~20% increase when hydrated, and bounded by double thin perivitelline membranes. The first mitotic cleavage occurred at 69min post-fertilization (pf) resulting in 2, 4 (2??2 array of cells), 8 (2??4), 16 (4??4), 32 (4??8), 64 (2??4??8) blastomeres, then developed to morula, blastula and gastrula stages. Blastula was featured by formation of enveloping layer and yolk syncytial layer. Onset of epiboly at 3h 57min depicted the commencement of gastrula while closure of blastopore at 11h 8min marked its completion. Neurulation period was distinct from segmentation where organogenesis was fully active. Embryo sudden muscular contraction was noticed at ~17h pf, increased prior to hatching with caudal locomotion firstly at 42s interval. Heartbeat of embryo commenced at ~1h before its unique eclosion at average of 72 beats/min while first larva emerged at 21h at a controlled temperature of 28.5??0.5C. Mean total length (TL) of larvae and their pouch thickness were 5??1mm and 0.05??0.02mm respectively. 1 -day old larvae revealed 8 distinctive neuromeres and by day 3, epicanthus folds of the eyes were fully uncovered; and thereafter commenced exogenous feeding. At day 4, larvae recorded mean TL of 9??1mm and 15 caudal fin rays. The fin bifurcation to dorsal and adipose fins was observed at third and half weeks post-hatchability with the dorsal fin length to adipose fin was 1.7:1. This study, for the first time, presents significant morpho-sequential developmental stages of H. bidorsalis and registers its unique form of eclosion. PMID:25512884

  7. Neoplecostomus doceensis: a new loricariid species (Teleostei, Siluriformes) from the rio Doce basin and comments about its putative origin

    PubMed Central

    Roxo, Fbio F.; Silva, Gabriel S. C.; Zawadzki, Cludio H.; Oliveira, Claudio

    2014-01-01

    Abstract A new species of Neoplecostomus is described from the rio Doce basin representing the first species of this genus in the basin. The new species is distinguished from its congeners by having enlarged, fleshy folds between dentaries, two or three series of developed papillae anterior to premaxillary teeth and a adipose-fin membrane present, and by lacking enlarged odontodes along snout lateral margins in mature males, a well-developed dorsal-fin spinelet wider than dorsal-fin spine base, lower number of lateral-line figs and developed membrane on the dorsal portion of the first, second and third pelvic-fin branched rays. Additionally, we present a brief discussion of biogeographic scenarios that may explain the distribution of the new species in the rio Doce basin. We suggested that the ancestral lineage of the new species reached the rio Doce from the upper portions of rio Paran drainages about 3.5 Mya (95% HPD: 1.65.5) indicating a colonization route of the N. doceensis ancestral lineage from the south end of Serra do Espinhao, probably as a result of headwater capture processes between the upper rio Paran and rio Doce basins. PMID:25317064

  8. Ontogeny and homology of the skeletal elements that form the sucking disc of remoras (Teleostei, Echeneoidei, Echeneidae).

    PubMed

    Britz, Ralf; Johnson, G David

    2012-12-01

    The sucking disc of the sharksuckers of the family Echeneidae is one of the most remarkable and most highly modified skeletal structures among vertebrates. We studied the development of the sucking disc based on a series of larval, juvenile, and adult echeneids ranging from 9.3 mm to 175 mm standard length. We revisited the question of the homology of the different skeletal parts that form the disc using an ontogenetic approach. We compared the initial stages of development of the disc with early developmental stages of the spinous dorsal fin in a representative of the morphologically basal percomorph Morone. We demonstrate that the "interneural rays" of echeneids are homologous with the proximal-middle radials of Morone and other teleosts and that the "intercalary bones" of sharksuckers are homologous with the distal radials of Morone and other teleosts. The "intercalary bones" or distal radials develop a pair of large wing-like lateral extensions in echeneids, not present in this form in any other teleost. Finally the "pectinated lamellae" are homologous with the fin spines of Morone and other acanthomorphs. The main part of each pectinated lamella is formed by bilateral extensions of the base of the fin spine just above its proximal tip, each of which develops a row of spinous projections, or spinules, along its posterior margin. The number of rows and the number of spinules increase with size, and they become autogenous from the body of the lamellae. We also provide a historical review of previous studies on the homology of the echeneid sucking disc and demonstrate that the most recent hypotheses, published in 2002, 2005 and 2006, are erroneous. PMID:22833478

  9. Review of the crevalle jacks, Caranx hippos complex (Teleostei: Carangidae), with a description of a new species from West Africa

    USGS Publications Warehouse

    Smith-Vaniz, W.F.; Carpenter, K.E.

    2007-01-01

    The Caranx hippos species complex comprises three extant species: crevalle jack (Caranx hippos) (Linnaeus, 1766) from both the western and eastern Atlantic oceans; Pacific crevalle jack (Caranx caninus) Gu??nther, 1868 from the eastern Pacific Ocean; and longfin crevalle jack (Caranx fischeri) new species, from the eastern Atlantic, including the Mediterranean Sea and Ascension Island. Adults of all three species are superficially similar with a black blotch on the lower half of the pectoral fin, a black spot on the upper margin of opercle, one or two pairs of enlarged symphyseal canines on the lower jaw, and a similar pattern of breast squamation. Each species has a different pattern of hyperostotic bone development and anal-fin color. The two sympatric eastern Atlantic species also differ from each other in number of dorsal- and anal-fin rays, and in large adults of C. fischeri the lobes of these fins are longer and the body is deeper. Caranx hippos from opposite sides of the Atlantic are virtually indistinguishable externally but differ consistently in the expression of hyperostosis of the first dorsal-fin pterygiophore. The fossil species Caranx carangopsis Steindachner 1859 appears to have been based on composite material of Trachurus sp. and a fourth species of the Caranx hippos complex. Patterns of hyperostotic bone development are compared in the nine (of 15 total) species of Caranx sensu stricto that exhibit hyperostosis.

  10. Ontogenic retinal changes in three ecologically distinct elopomorph fishes (Elopomorpha:Teleostei) correlate with light environment and behavior.

    PubMed

    Taylor, Scott M; Loew, Ellis R; Grace, Michael S

    2015-01-01

    Unlike the mammalian retina, the teleost fish retina undergoes persistent neurogenesis from intrinsic stem cells. In marine teleosts, most cone photoreceptor genesis occurs early in the embryonic and larval stages, and rods are added primarily during and after metamorphosis. This study demonstrates a developmental paradigm in elopomorph fishes in which retinas are rod-dominated in larvae, but undergo periods of later cone genesis. Retinal characteristics were compared at different developmental stages among three ecologically distinct elopomorph fishes-ladyfish (Elops saurus), bonefish (Albula vulpes), and speckled worm eel (Myrophis punctatus). The objectives were to improve our understanding of (1) the developmental strategy in the elopomorph retina, (2) the functional architecture of the retina as it relates to ecology, and (3) how the light environment influences photoreceptor genesis. Photoreceptor morphologies, distributions, and spectral absorption were studied at larval, juvenile, and adult stages. Premetamorphic retinas in all three species are rod-dominated, but the retinas of these species undergo dramatic change over the course of development, resulting in juvenile and adult retinal characteristics that correlate closely with ecology. Adult E. saurus has high rod densities, grouped photoreceptors, a reflective tapetum, and longer-wavelength photopigments, supporting vision in turbid, low-light conditions. Adult A. vulpes has high cone densities, low rod densities, and shorter-wavelength photopigments, supporting diurnal vision in shallow, clear water. M. punctatus loses cones during metamorphosis, develops new cones after settlement, and maintains high rod but low cone densities, supporting primarily nocturnal vision. M. punctatus secondary cone genesis occurs rapidly throughout the retina, suggesting a novel mechanism of vertebrate photoreceptor genesis. Finally, in postsettlement M. punctatus, the continuous presence or absence of visible light modulates rod distribution but does not affect secondary cone genesis, suggesting some degree of developmental plasticity influenced by the light environment. PMID:26241034

  11. Pluvial Drainage Patterns and Holocene Desiccation Influenced the Genetic Architecture of Relict Dace, Relictus solitarius (Teleostei: Cyprinidae)

    PubMed Central

    Houston, Derek D.; Evans, R. Paul; Shiozawa, Dennis K.

    2015-01-01

    Changing drainage patterns have played a significant role in the evolution of western North American aquatic taxa. Relict dace, Relictus solitarius, is a Great Basin endemic cyprinid with a native range that is restricted to four valleys in eastern Nevada. Relictus solitarius now occupies spring systems that are the remnants of Pleistocene-era pluvial lakes, although it may have occurred in the area for much longer. Here we use mitochondrial DNA sequence data to assess range-wide genetic diversity of R. solitarius, and to estimate divergence times to determine whether pluvial drainages played an important role in shaping intraspecific genetic diversity. Genetic diversification within R. solitarius began during the early to mid-Pleistocene, separating populations within two sets of valleys (Butte/Ruby and Goshute/Steptoe). Additional diversification in each of the two sets of valleys occurred more recently, in the mid- to late-Pleistocene. Holocene desiccation has further isolated populations, and each population sampled contains unique mtDNA haplotypes. Pluvial drainage patterns did contribute to the genetic structure observed within R. solitarius, but most of the intraspecific diversification does not appear to be associated with the Last Glacial Maximum. Holocene desiccation has also contributed to the observed genetic structure. The relict dace populations we sampled are all unique, and we recommend that future management efforts should strive to preserve as much of the genetic diversity as possible. PMID:26394395

  12. Growth of striated muscle fibres in the M. lateralis of the European eel Anguilla anguilla (L.) (Pisces, Teleostei).

    PubMed Central

    Willemse, J J; van den Berg, P G

    1978-01-01

    Diameters of red and white muscle fibres were measured in the M. lateralis of eels cultured under laboratory circumstances over a period of 2 years, starting from the glass eel stage. The red fibres of eels less than 10 cm are unique in that their growth involves increase in diameter only. Growth of the red fibres in eels greater than 10 cm, and of the white fibres in eels at all lengths considered, is characterized by an increase in number as well as diameter, the relative importance of these two methods of growth being related to factors other than the length of the animal. Satellite cells may play an important part in the addition of new, small muscle fibres. Images Fig. 8 PMID:640952

  13. Morphological evidence for a permeability barrier in the testis and spermatic duct of Gymnotus carapo (Teleostei: Gymnotidae).

    PubMed

    Meneguelli De Souza, Lara C; Retamal, Claudio A; Rocha, Gustavo M; Lopez, Maria Luisa

    2015-09-01

    Cell-cell interactions play essential roles in the regulation of gametogenesis. The involvement of junctional complexes in permeability barriers, for example, provides structural and physiological support for male germ-cell development. This study describes morphological characteristics of the reproductive system of Gymnotus carapo, a neo-tropical freshwater fish widely distributed in South and Central America, focusing on the detection of permeability barriers using morphological and biochemical approaches. Ultrastructural analysis of testes treated with the lanthanum nitrate exclusion technique showed that the tracer penetrated the interstitial compartment of the testis, surrounding and appearing within cysts containing spermatogonia and spermatocytes in early stages of meiosis, but was not detected in the spermatid cysts or inside the lumen of spermatogenic tubules. These results suggest the presence of a permeability barrier that is stabilized after meiosis is completed and serves to protect the haploid cells from the vascular system. In the spermatic-duct region, the tracer was obstructed near the lumen of the duct. Junctional complexes and focal tight junctions between adjacent cells were observed in the testis and spermatic duct. Freeze-fracture methods indeed confirmed the presence of tight junctions, which were visualized as parallel rows of individual particles between adjacent cells. More evidence supporting the existence of a permeability barrier was gathered from differences observed in the electrophoretic protein profiles of testis and spermatic-duct fluids compared to blood plasma. Together, these observations demonstrate the existence of a permeability barrier formed by tight junctions in the testis and spermatic duct of G. carapo. PMID:26073744

  14. A complex of species related to Paradiscogaster glebulae (Digenea: Faustulidae) in chaetodontid fishes (Teleostei: Perciformes) of the Great Barrier Reef.

    PubMed

    Diaz, Pablo E; Bray, Rodney A; Cutmore, Scott C; Ward, Selina; Cribb, Thomas H

    2015-10-01

    A total of 1523 individuals of 34 species of chaetodontids from the Great Barrier Reef were examined for faustulid trematodes. Specimens resembling Paradiscogaster glebulae Bray, Cribb & Barker, 1994 were found in nine chaetodontid species at three localities. These specimens are shown, on the basis of combined morphological and molecular analyses, to comprise a complex of morphologically similar and partly cryptic species. The complex may comprise as many as six distinct species of which three are resolved here. The true P. glebulae is identified in Chaetodon ornatissimus Cuvier, 1831, Chaetodon aureofasciatus Macleay, 1878, Chaetodon plebeius Cuvier, 1831, Chaetodon rainfordi McCulloch, 1923 and Chaetodon speculum Cuvier, 1831. Two new species are described, Paradiscogaster munozae n. sp. from Heniochus varius (Cuvier, 1829), Heniochus chrysostomus Cuvier, 1831 and Chaetodon citrinellus Cuvier, 1831 and Paradiscogaster melendezi n. sp. from Chaetodon kleinii Bloch, 1790. In terms of morphology the three species differ most clearly in the development of the appendages on the ventral sucker. The three species differ at 3-6consistent bp of ITS2 rDNA. The host-specificity of the three species differs strikingly. P. melendezi n. sp. infects just one fish species, P. glebulae infects species of only one clade of Chaetodon, and P. munozae n. sp. infects quite unrelated species. The basis of this unusual pattern of host-specificity requires further exploration. Two of the species recognised here, P. glebulae and P. munozae n. sp., showed apparent intra-individual variation in the ITS2 rDNA sequences as demonstrated by clear, replicated double peaks in the electropherograms. PMID:26096311

  15. Aporocotyle michaudi n. sp. (Digenea: Aporocotylidae) from the emerald rock cod, Trematomus bernacchii (Teleostei: Perciformes) in Antarctica.

    PubMed

    Santoro, Mario; Cipriani, Paolo; Pankov, Plamen; Lawton, Scott P

    2015-10-01

    Aporocotyle michaudi n. sp. is described from the gill blood vessels of the emerald rock cod Trematomus bernacchii in the Ross Sea, Antarctica. It is distinguished from all other species of Aporocotyle by its body tegument showing single conical spines, spinous buccal capsule, and genital atrium positioned medially; all congeners described to date are characterized by clusters of tegumental spines, unspined buccal capsule and genital atrium located in the lateral part of the body. Aporocotyle michaudi n. sp. clearly differs from A. notothenia (the only other species of Aporocotyle found in a perciform fish) in its shape and arrangement of tegumental spines, buccal capsule features, location of genital atrium, body size, ratio of esophagus/body length, anterior caeca/posterior caeca ratio, number of testes, cirrus sac and ovary size and shape, and host. The new species is easily distinguished from A. argentinensis (the species that most closely resembles A. michaudi) by the shape and arrangement of tegumental spines, buccal capsule features, genital atrium location, left anterior caecum longer than right, esophagus/body length ratio, number of testes, cirrus sac size and shape, host and molecular analyses. Phylogenetic analyses of partial 28S rDNA genetic data showed that sequences representing the new species form a distinct clade with all other sequences for species of Aporocotyle and appear basal within the genus. Aporocotyle michaudi n. sp. represents the only species of genus described in Antarctica. PMID:25979611

  16. [NADPH-diaphorase, nitric oxide synthase, and tyrosine hydroxylase in the diencephalon of the Rhodeus sericeus (Cyprynidae:Teleostei)].

    PubMed

    Pushchina, E V; Obukhov, D K

    2010-01-01

    The presence and distribution of nitric oxide synthase (NOS)-like neurons as well as tyrosine hydroxylase-immunoreactive (TH) neurons was studied in the diencephalon of the cypriniform teleost Rhodeus sericeus. The anatomical relationships between tyrosine hydroxylase (TH)- and nitric oxide synthase (NOS)-containing cells were visualized both by NOS-immunohistochemistry and NADPH-histochemistry. Immunohistochemical labeling and morphological studies were performed on the same sections. The results reported in this paper show that both a NOS and TH activity are present in the preoptic region, posterior tuberculum, paraventricular organ and hypothalamus of R. sericeus. Putative nitrergic neurons were identified in all major hypophysiotrophic nuclei of the R. sericeus brain using both NADPH-d histochemistry and nNOS immunohistochemistry. In the preoptic region, nitrergic neurons were found in both the parvocellular and the magnocellular nuclei. Within these nuclei, the distribution of NADPH-d reactivity was similar to that of nNOS immunoreactivity. However, we found no evidence of colocalization of NADPH-d and nNOS in consecutive sections. NOS- and TH-containing neurons were observed in all the nuclei under study (hypothalamus, posterior tuberculum, ventral thalamus) and telencephalon (preoptic region), although most neurons showing the coexistence of both substances were mainly located in the preoptic nucleus and hypothalamus, some labelled neurons were found in the posterior tuberculum. Most of the cerebrospinalliquor-contacting cells (LCNs) in diencephalic periventricular area of R. sericeus were TH-immunoreactive. Also, a large number ofnitrergic small LCNs distributed throughout the third ventricle were observed in these regions. The data obtained supports the existence of a nitrergic circumventricular system in teleost. LCNs in R. sericeus are thought to be involved in osmoregulatory functions as osmosensitive neurons. Due to their chemical properties, NO produced by these cells might play an important role in the maintenance and regulation of CSF homeostasis through the modulation of cerebral blood flow. PMID:21105363

  17. The Inner Ear and its Coupling to the Swim Bladder in the Deep-Sea Fish Antimora rostrata (Teleostei: Moridae)

    PubMed Central

    Deng, Xiaohong; Wagner, Hans-Joachim; Popper, Arthur N.

    2011-01-01

    The inner ear structure of Antimora rostrata and its coupling to the swim bladder were analyzed and compared with the inner ears of several shallow-water species that also have similar coupling. The inner ear of Antimora has a long saccular otolith and sensory epithelium as compared to many other fishes. Some parts of the membranous labyrinth are thick and rigid, while other parts are thinner but attached tightly to the bony capsule. The partially rigid membranous labyrinth, along with its intimate connection to the swim bladder, may help the inner ear follow the sound oscillations from the swim bladder with better precision than would occur in a less rigid inner ear. In addition, the saccular sensory epithelium has an elaborate structure and an anterior enlargement that may be correlated with increased hearing sensitivity. Some of the features in the inner ear of Antimora may reflect the functional specialization of deep-water living and support the hypothesis that there is enhanced inner ear sensitivity in some deep-sea fishes. PMID:21532967

  18. Cryptomyrus: a new genus of Mormyridae (Teleostei, Osteoglossomorpha) with two new species from Gabon, West-Central Africa

    PubMed Central

    Sullivan, John P.; Lavoué, Sébastien; Hopkins, Carl D.

    2016-01-01

    Abstract We use mitochondrial and nuclear sequence data to show that three weakly electric mormyrid fish specimens collected at three widely separated localities in Gabon, Africa over a 13-year period represent an unrecognized lineage within the subfamily Mormyrinae and determine its phylogenetic position with respect to other taxa. We describe these three specimens as a new genus containing two new species. Cryptomyrus, new genus, is readily distinguished from all other mormyrid genera by a combination of features of squamation, morphometrics, and dental attributes. Cryptomyrus ogoouensis, new species, is differentiated from its single congener, Cryptomyrus ona, new species, by the possession of an anal-fin origin located well in advance of the dorsal fin, a narrow caudal peduncle and caudal-fin lobes nearly as long as the peduncle. In Cryptomyrus ona, the anal-fin origin is located only slightly in advance of the dorsal fin, the caudal peduncle is deep and the caudal-fin lobes considerably shorter than the peduncle. Continued discovery of new taxa within the “Lower Guinea Clade” of Mormyridae highlights the incompleteness of our knowledge of fish diversity in West-Central Africa. We present a revised key to the mormyrid genera of Lower Guinea. PMID:27006619

  19. Kudoa unicapsula n. sp. (Myxosporea: Kudoidae) a parasite of the Mediterranean mullets Liza ramada and L. aurata (Teleostei: Mugilidae).

    PubMed

    Yurakhno, V M; Ovcharenko, M O; Holzer, A S; Sarabeev, V L; Balbuena, J A

    2007-11-01

    A new multivalvulid myxozoan parasite, Kudoa unicapsula n. sp., is described from the intestinal mesentery, intestine and pyloric caeca of the thin-lipped grey mullet Liza ramada (Risso 1826) and the golden grey mullet L. aurata (Risso, 1810) from the Mediterranean coastal waters of Spain. It is characterized by the presence of elongated, rice corn-like white cysts of 0.47-0.56 x 0.18-0.38 mm, filled with tetracapsulate, slightly asymmetric spores, rectangular in apical view and tear-shaped in lateral view with four polar capsules of considerably different size and slightly unequal spore valves with rounded edges, overlapping each other on the apex of the spore. One large polar capsule includes a polar filament coiled in two to three turns, and the other three polar capsules, which are very small, posses only a rudimental filament. Both light and electron microscopy data showed that this species differs from all previously described Kudoa spp. with unequal polar capsules. The molecular analysis based on 18S and 28S ribosomal deoxyribonucleic acid DNA sequence data of K. unicapsula n. sp. indicates a close relationship and thus phylogenetic clustering together with K. trifolia, a myxozoan from the same host and the same geographical location. PMID:17846792

  20. Renaming of three recently described eels of the genus Neenchelys (Teleostei: Anguilliformes: Ophichthidae) from the western Pacific.

    PubMed

    Ho, Hsuan-Ching; Mccosker, John E; Smith, David G

    2015-01-01

    In our earlier paper (Ho et al., 2013), we described three new species of the eel genus Neenchelys Bamber, 1915. Unfortunately, the critical step of registering the work in ZooBank was omitted, thus rendering the names unavailable. In this paper, we present abbreviated descriptions of the new species in order to make these names available in accordance with the amended Article 8.5 of the International Code of Zoological Nomenclature. PMID:26701589

  1. Species-level phylogeny of 'Satan's perches' based on discordant gene trees (Teleostei: Cichlidae: Satanoperca Günther 1862).

    PubMed

    Willis, Stuart C; López-Fernández, Hernán; Montaña, Carmen G; Farias, Izeni P; Ortí, Guillermo

    2012-06-01

    Neotropical rivers are home to the largest assemblage of freshwater fishes, but little is known about the phylogeny of these fishes at the species level using multi-locus molecular markers. Here, we present a phylogeny for all known species of the genus Satanoperca, a widespread group of Neotropical cichlid fishes, based on analysis of six unlinked genetic loci. To test nominal and proposed species limits for this group, we surveyed mtDNA sequence variation among 320 individuals representing all know species. Most nominal species were supported by this approach but we determined that populations in the Xingu, Tapajós, and Araguaia+Paraná Rivers are likely undescribed species, while S. jurupari and S. mapiritensis did not show clear genetic distinction. To infer a phylogeny of these putative species, we conducted maximum likelihood and Bayesian non-clock and relaxed clock analyses of concatenated data from three genes (one mitochondrial, two nuclear). We also used a multi-species coalescent model to estimate a species tree from six unlinked loci (one mitochondrial, five nuclear). The topologies obtained were congruent with other results, but showed only minimal to moderate support for some nodes, suggesting that more loci will be needed to satisfactorily estimate the distribution of coalescent histories within Satanoperca. We determined that this variation results from topological discordance among separate gene trees, likely due to differential sorting of ancestral polymorphisms. PMID:22406409

  2. Description of three new species of Moenkhausia (Teleostei, Characiformes, Characidae) with the definition of the Moenkhausia jamesi species complex.

    PubMed

    Petrolli, Marina G; Benine, Ricardo C

    2015-01-01

    From the examination of extensive comparative material currently identified as M. jamesi we verified that there are, at least, three new species under this name. These, along with M. jamesi and M. justae, form what we herein called the M. jamesi species complex, by sharing the following group of characters: a short maxilla, with its distal margin not exceeding anterior third of the second infraorbital; first through third teeth of the inner row of premaxilla and first and second dentary teeth with cusps arranged in a pronounced arch, humeral spot positioned between the fourth and seventh scales of the lateral line and extending up to four scale rows above the lateral line and one scale row below the lateral line, and a vertically oval to round spot at the base of the caudal fin rays. Moenkhausia ischyognatha sp. n., from Rio Xingu basin, differs from the other species of the complex by its lower head depth. Moenkhausia alesis sp. n., from the river system Tocantins-Araguaia, differs from M. jamesi, M. ischyognatha, and M. sthenosthoma by the number of scale rows above the lateral line. Moenkhausia sthenosthoma sp. n., from the Rio Madeira basin, differs from M. jamesi by the number of scale rows between the lateral line and the midventral scale series. Moenkhausia justae can be diagnosed from the other species of the complex by having a tri to pentacuspidate tooth on the maxilla. PMID:26250196

  3. Helicometrina nimia Linton, 1910 (Digenea: Opecoelidae) in dusky grouper Epinephelus marginatus (Lowe, 1834) (Teleostei: Serranidae) from southeastern Brazil.

    PubMed

    Roumbedakis, K; Marchiori, N C; Garcia, P; Pereira Junior, J; Castro, L A S; Martins, M L

    2014-05-01

    Helicometrina nimia (Opecoelidae) is a digenean with wide distribution. Fish families most commonly used as hosts for H. nimia are Serranidae, Pomodasydae, Scorpaenidae and Clinidae. In the present study, a new host and a new host locality are presented for the species. A description of the studied specimens, besides comments concerning its taxonomic status and biometrically compared tables of H. nimia reports are given. The taxonomic status of members of Helicometrina has been questionable. The greatest controversy for the genus seems to be related to the validity of diagnostic features, especially in regard to the number of testes. In the present study, all studied specimens presented a permanent and steady number of testes (n=9) and therefore its use as a diagnostic character is supported by the present authors. Epinephelus marginatus is considered a new host for Helicometrina nimia, and So Paulo state, southeastern Brazil, a new locality for the species. PMID:25166333

  4. Pollution biomonitoring in the Bizerte lagoon (Tunisia), using combined chemical and biomarker analyses in grass goby, Zosterisessor ophiocephalus (Teleostei, Gobiidae).

    PubMed

    Barhoumi, Badreddine; Clérandeau, Christelle; Gourves, Pierre-Yves; Le Menach, Karyn; El Megdiche, Yassine; Peluhet, Laurent; Budzinski, Hélène; Baudrimont, Magalie; Driss, Mohamed Ridha; Cachot, Jérôme

    2014-10-01

    In this study, biological responses and contaminant levels in biological tissues were investigated in grass goby fish specimens (Zosterisessor ophiocephalus) collected from five stations in a moderately polluted ecosystem, namely the Bizerte lagoon on the north coast of Tunisia. The following biomarkers were measured: muscular acetylcholinesterase (AChE), hepatic ethoxyresorufin-O-deethylase (EROD), glutathione-S-transferase (GST), catalase (CAT), lipoperoxidation (TBARS), condition factor (CF), and hepatosomatic index (HSI). These measurements were taken in parallel with the content of Organochlorine pesticides (OCPs), Polychlorinated biphenyls (PCBs), Polycyclic aromatic hydrocarbons (PAHs) and trace metals (As, Cr, Cu, Mn, Pb, V, Zn, Ag, Cd, Co and Ni) in muscle tissue. Total PAH concentrations ranged from 20.09 ± 0.68 to 105.77 ± 42.58 ng g(-1) dw, PCB from 33.19 ± 6.25 to 126.28 ± 7.37 ng g(-1) dw, OCP from 11.26 ± 1.62 to 19.17 ± 2.06 ng g(-1) dw, and metals from 107.83 ± 1.83 to 187.21 ± 2.00 mg/kg dw. The highest levels of pollutants and biomarkers were observed at station S1, located in the Bizerte channel. Elevated EROD, GST and CAT activities, as well as TBARS levels in liver were positively correlated with tissue contaminant levels at station S1. Significant negative correlations were also found between hexachlorobenzene (HCB) and dichlorodiphenyltrichloroethane (DDTs) body burden with AChE activity in muscle at station S2. The integration of biological responses and contaminant tissue content indicated that certain areas of the Bizerte lagoon, notably station S1, are significantly impacted by various human activities, which likely represent a threat for aquatic wildlife. On the basis of these results, and due to its ecological characteristics, the grass goby appears a suitable indicator species for pollution biomonitoring in coastal marine areas along the Mediterranean Sea. PMID:25106667

  5. Some aspects of the biology and ecology of Knipowitschia caucasica (Teleostei: Gobiidae) in the Evros Delta (North Aegean Sea)

    NASA Astrophysics Data System (ADS)

    Kevrekidis, T.; Kokkinakis, A. K.; Koukouras, A.

    1990-06-01

    Some aspects of the biology and ecology of the goby Knipowitschia caucasica were studied over a period of 13 months in a poly-to euhaline area in the Evros Delta (North Aegean Sea). This fish grows rapidly in the summer and autumn after hatching, matures after its first winter, breeds from the end of April to the end of July, and grows rapidly again in July September. The older males perish after their second February, whereas some females have a second breeding season at the end of April/beginning of May, shortly before their death. The fish grows to about 40 mm in total length. There is a positive correlation between the total length (TL) and the standard length (SL) or the cleaned body weight (CW). SL increases slower than TL, whereas CW increases slower than TL in immature individuals and faster in males and females. There is no difference between immature individuals, males and females, in the growth rate of SL, TL and CW, TL. The mean monthly values of the condition factor varies from 0.289 to 0.576 in females and from 0.313 to 0.548 in males. The overall sex ratio of females to males is 1: 1.46. Fecundity ranges from 60 to 217 eggs with a mean value of 109.8 and depends upon size, whereas relative fecundity varies between 968 and 2170 with a mean of 1558. The fish feeds predominantly on benthic amphipods and polychaetes.

  6. First evidence for interspecific hybridization between invasive goby species Neogobius fluviatilis and Neogobius melanostomus (Teleostei: Gobiidae: Benthophilinae).

    PubMed

    Lindner, K; Cerwenka, A F; Brandner, J; Gertzen, S; Borcherding, J; Geist, J; Schliewen, U K

    2013-06-01

    Two hybrids between the monkey goby Neogobius fluviatilis and the round goby Neogobius melanostomus from the Rhine River were identified by genotyping and morphological comparison. These are the first records of goby-hybrids outside the parent species' native ranges worldwide. PMID:23731157

  7. Callogobius liolepis Bleeker, a senior synonym of Gobiopsis aporia Lachner and McKinney (Teleostei: Gobiidae: Gobiopsis).

    PubMed

    Delventhal, Naomi R; Mooi, Randall D

    2014-01-01

    Callogobius liolepis Bleeker in Koumans was briefly described from two specimens from Ambon. A later, more detailed description by Koumans was apparently based on Bleeker's unpublished description and specimens of C. okinawae (Snyder), considerably complicating the taxonomy of several species. Re-examination of the syntypes identifies C. liolepis as a species of the genus Gobiopsis Steindachner due to the absence of raised vertical ridges of papillae that characterise Callogobius and the presence of barbels in a pattern unique among gobiids to a subset of Gobiopsis. Gobiopsis liolepis (Bleeker) is determined as the senior synonym of G. aporia Lachner and McKinney based on the absence of head pores combined with the presence of a series of tightly spaced papillae over the eye, lateral scale counts of 36-42, pectoral-fin ray counts of 20-21, dorsal-fin ray counts VI+I,10 and anal-fin ray counts of I,9. The larger syntype is designated the lectotype and the smaller the paralectotype. Specimens identified as C. liolepis in museums or the literature are likely referable to C. okinawae (Snyder) or C. bifasciatus (Smith). PMID:24870626

  8. Chriolepis bilix, a new species of goby (Teleostei: Gobiidae) from deep waters of the western Atlantic.

    PubMed

    Hastings, Philip A; Findley, Lloyd T

    2013-01-01

    A new species of seven-spined goby of the genus Chriolepis is described from four specimens from four widely separate western Atlantic localities (Little Bahama Bank; off southwestern Florida; Tobago Island; and northeastern Colombia) from depths ranging from 62 to 138 m. The species is distinct from all other western Atlantic species currently assigned to the genus Chriolepis in having a fully scaled body, the first two dorsal-fin spines greatly elongated in both sexes, especially so in females, and two anal-fin pterygiophores inserted anterior to the first haemal spine. It differs from members of the similar genus Varicus in having branched pelvic-fins rays, a longer fifth pelvic-fin ray and more numerous meristic elements. It closely resembles Chriolepis atrimelum, known from a similar depth at Isla del Coco in the eastern Pacific Ocean.  PMID:25113374

  9. Molecular phylogeny of Percomorpha resolves Trichonotus as the sister lineage to Gobioidei (Teleostei: Gobiiformes) and confirms the polyphyly of Trachinoidei.

    PubMed

    Thacker, Christine E; Satoh, Takashi P; Katayama, Eri; Harrington, Richard C; Eytan, Ron I; Near, Thomas J

    2015-12-01

    The percomorph fish clade Gobiiformes is a worldwide, tropical and temperate radiation with species occupying nearly all aquatic, and some semi-terrestrial, habitats. Early molecular phylogenetic studies led to the discovery of Gobiiformes, which contains Gobioidei, the gobies and sleepers, and a clade (Apogonoidei) consisting of Apogonidae and Kurtus, the cardinalfishes and nurseryfishes. Gobioidei is consistently resolved as monophyletic in molecular studies, and includes eight families whose members range from waterfall climbing stream gobies to several prominent lineages inhabiting coral reefs. The sister taxon to Gobioidei is also reliably resolved as Apogonoidei. Despite the consistent support for gobiiform monophyly in molecular studies, it is not known if percomorph lineages unsampled in molecular phylogenetic studies are closely related to Gobioidei or Apogonoidei. Here we assemble a large dataset of DNA sequence from ten protein-coding genes, sampling widely across Acanthomorpha and Percomorpha, including Gobioidei, Apogonidae, and Kurtus, along with representatives of all twelve families comprising the former Trachinoidei. The phylogenies inferred from the nuclear gene sequences show that Trachinoidei is polyphyletic, with constituent lineages spread widely among several major percomorph clades. Most notably, the sanddivers (Trichonotus) are resolved as the sister lineage of Gobioidei. This study clarifies the phylogenetic relationships of lineages previously classified in Trachinoidei, identifies Trichonotus as the sister lineage of gobies, provides a molecular phylogeny of the major lineages of Gobioidei, and offers suggested changes to percomorph classification. PMID:26265255

  10. Two new species of myxosporean parasites (Myxosporea: Bivalvulida) from gall bladders of Macruronus magellanicus Lnnberg, 1907 (Teleostei: Merlucciidae).

    PubMed

    Kalavati, Chaganti; Mackenzie, Ken; Collins, Catherine; Hemmingsen, Willy; Brickle, Paul

    2013-01-01

    Two new species of myxosporeans are described from the gall bladders of hoki, Macruronus magellanicus Lnnberg, 1907, caught in the Southeast Pacific off Chile and in the Southwest Atlantic off the Falkland Islands. Pseudalataspora kovalevae n. sp. is described morphologically and genetically. Of the 12 species of Pseudalataspora previously described from the gall bladders of marine fish, P. kovalevae is most similar in morphology to P. umbraculiformis Gaevskaya and Kovaleva, 1984. The 18S rRNA gene sequence from P. kovalevae is the first for a member of the genus Pseudalataspora. Based on currently available myxosporean 18S rRNA gene sequence data, P. kovalevae shares greatest sequence identity with species of the genus Ceratomyxa (C. anko and C. pantherini). Palliatus magellanicus n. sp. is described morphologically only; it differs considerably in morphology, host species and locality from the five other Palliatus species described from marine fishes. A third species from the gall bladder is also described morphologically and genetically. On the basis of its morphology it is tentatively identified as Myxidium baueri Kovaleva and Gaevskaya, 1982, for which M. magellanicus is a new host record. Molecular analysis indicates that, of those species for which data are available, M. baueri is most closely related to Myxidium coryphaenoideum Noble, 1966 based on 18S rRNA gene sequence data, though support for a phylogenetic grouping is low. PMID:26295127

  11. Isolation and characterization of polymorphic microsatellite loci in the freshwater fishes Telestes souffia and Telestes muticellus (Teleostei: Cyprinidae).

    PubMed

    Dubut, Vincent; Martin, Jean-Franois; Costedoat, Caroline; Chappaz, Rmi; Gilles, Andr

    2009-05-01

    Ten novel polymorphic microsatellites (seven with perfect motifs) were isolated from vairone species (Telestes souffia and Telestes muticellus), which are endangered European cyprinid species. Together with 11 previously published cyprinid-specific loci, five multiplex sets were optimized, allowing the genotyping of 21 polymorphic loci. The level of genetic diversity was assessed in 97 individuals from the two species T. souffia and T. muticellus. We also successfully applied the 21 microsatellites to nine related species. These primers will thus be useful in assessing population structure of the vairone and other cyprinid species, with application for conservation issues and phylogeographical approaches. PMID:21564819

  12. Ultrastructure and phylogeny of Ceratomyxa auratae n. sp. (Myxosporea: Ceratomyxidae), a parasite infecting the gilthead seabream Sparus aurata (Teleostei: Sparidae).

    PubMed

    Rocha, Snia; Casal, Graa; Rangel, Lus; Castro, Ricardo; Severino, Ricardo; Azevedo, Carlos; Santos, Maria Joo

    2015-10-01

    A new myxosporean parasite is described from the gall bladder of the gilthead seabream Sparus aurata in a Southern Portuguese fish farm, with basis on light and transmission electron microscopy, as well as in molecular procedures. In the bile, young and mature mono- to disporic plasmodia were elliptical and presented smooth surface membranes. Crescent-shaped myxospores measured 6.70.7 (5.3-7.6) ?m in length and 27.03.0 (19.7-31.2) ?m in thickness. The myxospore wall was constituted by two symmetrical valves united along a slightly curved suture line, each presenting a lateral projection with a rounded end. Two equal-sized subspherical polar capsules, measuring 3.60.2 (2.9-3.8) ?m in length and 3.50.3 (2.9-3.8) ?m in width, were located at the same level, each displaying a polar filament coiled in 5 turns. Molecular analysis of the SSU rRNA gene confirmed the parasite as a new member of the genus Ceratomyxa, making this the fourth report of Ceratomyxa from the gall bladder of S. aurata in the Iberian Peninsula. This reinforces the assumption that species richness of ceratomyxids in South European sparids is high, but the phylogenetic analysis performed disagrees with the existence of a common ancestor for Ceratomyxa species infecting sparid hosts, as well as their clustering according to geographical location. The main Ceratomyxa clade is not monophyletic due to the inclusion of Palliatus indecorus and Pseudoalatospora kovalevae; a situation that will probably be resolved by the taxonomic revision of these genera. PMID:25892564

  13. Crystallaria cincotta, a new species of darter (Teleostei: Percidae) from the Elk River of the Ohio River drainage, West Virginia

    USGS Publications Warehouse

    Welsh, S.A.; Wood, R.M.

    2008-01-01

    A new species of percid, Crystallaria cincotta, is described from the Cumberland, Elk, Green, and Muskingum river drainages of the Ohio River basin, USA. It differs from populations of Crystallaria asprella of the Gulf Coast, lower Mississippi River, middle Mississippi River, upper Mississippi River, and Wabash River drainages by having a reduced number of cheek scale rows restricted to the post-orbital region, a falcate margin on the pelvic fins, a preorbital blotch distinctly separate from the anterior orbital rim, and a wide mouth gape. The Elk River population is also divergent genetically from populations of the Gulf Coast, lower Mississippi River, and upper Mississippi River drainages. Crystallaria cincotta, discovered in the Elk River of the Ohio River drainage in 1980, is a rare species with the only extant population represented by 12 individuals collected from 1980-2005 from the lower 36 km section of the Elk River, West Virginia. Copyright ?? 2008 Magnolia Press.

  14. Four new species of coral gobies (Teleostei: Gobiidae: Gobiodon), with comments on their relationships within the genus.

    PubMed

    Herler, Juergen; Bogorodsky, Sergey V; Suzuki, Toshiyuki

    2013-01-01

    Four new species of the coral-associated gobiid genus Gobiodon were discovered in the Red Sea. Although several of these species are common not only in the Red Sea but also in the Indian and western Pacific Ocean, they have not been described before. Detailed descriptions of the four species are based on morphological and molecular genetic (mitochondrial 12s and 16s rRNA) investigations. The new species, like most species of the genus, lack scales and have species-specific life colouration. Gobiodon bilineatus sp. nov. is the closest relative to G. quinquestrigatus (Valenciennes) and of G. sp. D (Munday et al.), and has five distinct, blue lines on the head as juveniles and subadults, which disappear in adults, and which are often uniformly orange-red with two distinct, vertical blue lines through each eye. Gobiodon irregularis sp. nov. has been confused with the former new species in the past, and is closely related to G oculolineatus Wu, but is unmistakable in live colouration. Juveniles are characterised by a transparent body, red bars on the head with bluish to greyish interspaces, and irregular red lines and dots on the nape and dorsally on the body. Adults are usually uniformly brown or green-brown, with only remnants of the bars through the eye and below the orbit. Gobiodon ater sp. nov. is a small, entirely black species and can be easily confused with other black species, although it is genetically clearly distinct from G. ceramensis Bleeker and its black relatives. Gobiodonfuscoruber sp. nov. is likely to be the closest relative of G ater sp. nov., but is uniformly reddish-brown or brown, has bright median fin margins (at least in the Red Sea), and grows considerably larger than G. ater. It has been genetically determined that G. fuscoruber sp. nov. is identical with an Indian Ocean/western Pacific species that has been called G. unicolor Castelnau by several authors. However, examination of the holotype of G unicolor, including the original description, revealed that the type species and original description are clearly different from the species frequently called G. unicolor. The holotype resembles G. histrio (Valenciennes) and the name G. unicolor must therefore be considered a junior synonym of G. histrio. As a consequence, a new name for this species is provided. PMID:24511221

  15. A comparative study of Ligophorus uruguayense and L. saladensis (Monogenea: Ancyrocephalidae) from Mugil liza (Teleostei: Mugilidae) in southern Brazil.

    PubMed

    Marchiori, Natalia C; Pariselle, Antoine; Pereira, Joaber; Agnese, Jean-Francois; Durand, Jean-Dominique; Vanhove, Maarten P M

    2015-01-01

    Representatives of Ligophorus Euzet et Suriano, 1977 were found on the gills of Mugil liza Valenciennes caught in southern Brazil. They were identified as Ligophorus uruguayense Failla Siquier et Ostrowski de Nez, 2009 and Ligophorus saladensis Marcotegui et Martorelli, 2009, even though specific identification proved to be difficult due to inconsistencies in some diagnostic features reported for these two species. Therefore, a combined morphological and molecular approach was used to critically review the validity of these species, by means of phase contrast and confocal fluorescence microscopical examination of sclerotised hard parts, and assessing the genetic divergence between L. saladensis, L. uruguayense and their congeners using rDNA sequences. The main morphological differences between the two species relate to the shape of the accessory piece of the penis and the median process of the ventral bar. The accessory piece in L. uruguayense is shorter than in L. saladensis, has a cylindrical, convex upper lobe and straight lower lobe (vs with the distal tip of the lower lobe turning away from the upper lobe in the latter species). The ventral bar has a V-shaped anterior median part in L. uruguayense (vs U-shaped in L. saladensis). The two species are suggested to be part of a species complex together with L. mediterraneus Sarabeev, Balbuena et Euzet, 2005. We recommend to generalise such comparative assessment of species of Ligophorus for a reliable picture of the diversity and diversification mechanisms within the genus, and to make full use of its potential as an additional marker for mullet taxonomy and systematics. PMID:25960568

  16. The role of continental shelf width in determining freshwater phylogeographic patterns in south-eastern Australian pygmy perches (Teleostei: Percichthyidae).

    PubMed

    Unmack, Peter J; Hammer, Michael P; Adams, Mark; Johnson, Jerald B; Dowling, Thomas E

    2013-03-01

    Biogeographic patterns displayed by obligate freshwater organisms are intimately related to the nature and extent of connectivity between suitable habitats. Two of the more significant barriers to freshwater connections are seawater and major drainage divides. South-eastern Australia provides a contrast between these barriers as it has discrete areas that are likely influenced to a greater or lesser extent by each barrier type. We use continental shelf width as a proxy for the potential degree of river coalescence during low sea levels. Our specific hypothesis is that the degree of phylogeographic divergence between coastal river basins should correspond to the continental shelf width of each region. This predicts that genetic divergences between river basins should be lowest in regions with a wider continental shelf and that regions with similar continental shelf width should have similar genetic divergences. Pygmy perches (Nannoperca australis and Nannoperca 'flindersi') in south-eastern Australia provide an ideal opportunity to test these biogeographic hypotheses. Phylogeographic patterns were examined based on range-wide sampling of 82 populations for cytochrome b and 23 polymorphic allozyme loci. Our results recovered only limited support for our continental shelf width hypothesis, although patterns within Bass clade were largely congruent with reconstructed low sea-level drainage patterns. In addition, we identified several instances of drainage divide crossings, typically associated with low elevational differences. Our results demonstrate high levels of genetic heterogeneity with important conservation implications, especially for declining populations in the Murray-Darling Basin and a highly restricted disjunct population in Ansons River, Tasmania. PMID:23398527

  17. A new record of a flathead fish (Teleostei: Platycephalidae) from China based on morphological characters and DNA barcoding

    NASA Astrophysics Data System (ADS)

    Qin, Yan; Song, Na; Zou, Jianwei; Zhang, Zhaohui; Cheng, Guangping; Gao, Tianxiang; Zhang, Xiumei

    2013-05-01

    A new record of Platycephalus sp.1 (sensu Nakabo, 2002) was documented based on morphological characters and DNA barcoding. We collected 174 specimens of the genus Platycephalus from Chinese coastal waters of Dongying, Qingdao, Zhoushan, and Beihai. Samples were identified as Platycephalus sp.1 morphologically. The coloration, meristic traits, and morphometric measurements are consistent with previously published records. In brief, it is an orange-brown flathead fish with dark brown spots scattered on head and body, lateral line scales 83 to 99 with one or two spine-bearing anteriormost pored scale, no yellow blotch on the caudal fin. Cytochrome oxidase I subunit (COI) gene fragments were sequenced for phylogenetic analysis. The mean evolutionary distance within the species Platycephalus sp.1 was 0.1%. Net evolutionary distances between Platycephalus sp.1 and other species of Platycephalus ranged from 10.8% to 19.7%, which is much greater than the threshold for species delimitation. The COI sequence analysis strongly supports the validity of Platyceohalus sp.1 at genetic level.

  18. Mapping the potential distribution of the invasive Red Shiner, Cyprinella lutrensis (Teleostei: Cyprinidae) across waterways of the conterminous United States

    USGS Publications Warehouse

    Poulos, Helen M.; Chernoff, Barry; Fuller, Pam L.; Butman, David

    2012-01-01

    Predicting the future spread of non-native aquatic species continues to be a high priority for natural resource managers striving to maintain biodiversity and ecosystem function. Modeling the potential distributions of alien aquatic species through spatially explicit mapping is an increasingly important tool for risk assessment and prediction. Habitat modeling also facilitates the identification of key environmental variables influencing species distributions. We modeled the potential distribution of an aggressive invasive minnow, the red shiner (Cyprinella lutrensis), in waterways of the conterminous United States using maximum entropy (Maxent). We used inventory records from the USGS Nonindigenous Aquatic Species Database, native records for C. lutrensis from museum collections, and a geographic information system of 20 raster climatic and environmental variables to produce a map of potential red shiner habitat. Summer climatic variables were the most important environmental predictors of C. lutrensis distribution, which was consistent with the high temperature tolerance of this species. Results from this study provide insights into the locations and environmental conditions in the US that are susceptible to red shiner invasion.

  19. Male mate choice and sperm allocation in a sexual/asexual mating complex of Poecilia (Poeciliidae, Teleostei)

    PubMed Central

    Schlupp, I; Plath, M

    2005-01-01

    Male mate choice is critical for understanding the evolution and maintenance of sexual/asexual mating complexes involving sperm-dependent, gynogenetic species. Amazon mollies (Poecilia formosa) require sperm to trigger embryogenesis, but the males (e.g. Poecilia mexicana) do not contribute genes. Males benefit from mating with Amazon mollies, because such matings make males more attractive to conspecific females, but they might control the cost of such matings by providing less sperm to Amazon mollies. We examined this at the behavioural and sperm levels. P. mexicana males preferred to mate with, and transferred more sperm to conspecific females. However, if males mated with P. formosa, sperm was readily transferred. This underscores the importance of male choice in this system. PMID:17148157

  20. Otolith morphology and hearing abilities in cave- and surface-dwelling ecotypes of the Atlantic molly, Poecilia mexicana (Teleostei: Poeciliidae)

    PubMed Central

    Schulz-Mirbach, Tanja; Ladich, Friedrich; Riesch, Rdiger; Plath, Martin

    2010-01-01

    Cave fish have rarely been investigated with regard to their inner ear morphology, hearing abilities, and acoustic communication. Based on a previous study that revealed morphological differences in the saccular otolith between a cave and two surface populations of Poecilia mexicana, we checked for additional differences in utricular and lagenar otoliths and tested whether different populations have similar hearing sensitivities. We found pronounced differences in the shape of all three otoliths. Otoliths of the saccule and lagena from cave fish differed from those of surface fish in the features of the face oriented towards the sensory epithelium. In addition, otoliths of the utricle and lagena were significantly heavier in cave fish. Auditory sensitivities were measured between 100 and 1500Hz, utilizing the auditory evoked potential recording technique. We found similar hearing abilities in cave and surface fish, with greatest sensitivity between 200 and 300Hz. An acoustic survey revealed that neither ecotype produced species-specific sounds. Our data indicate that cave dwelling altered the otolith morphology in Atlantic mollies, probably due to metabolic differences. Different otolith morphology, however, did not affect general auditory sensitivity or acoustic behavior. PMID:20430090

  1. A New Species of Ligophorus (Monogenea: Dactylogyridae) from the gills of the Flathead Mullet Mugil cephalus (Teleostei: Mugilidae) from Mexico.

    PubMed

    Rodrguez-Gonzlez, Abril; Mguez-Lozano, Ral; Llopis-Belenguer, Cristina; Balbuena, Juan Antonio

    2015-12-01

    A new monogenean species, Ligophorus yucatanensis n. sp. from the gills of the flathead mullet Mugil cephalus from the Yucatan Peninsula, Mexico, is described. The new species can be differentiated from all other species of Ligophorus by the morphology of the accessory piece of the copulatory organ. Its main lobe is cylindrical, tunnelled expanded distally, slightly bowed with a characteristic membranous opening at level of medial bifurcation of the accessory piece, forming a thick-walled bulbshaped expansion that ends in a round labium. The secondary lobe is spatulate, straight, and shorter than the main lobe. In addition, the new species can be distinguished from other species by the morphology of the haptoral ventral bar, and the distal end of the vaginal duct. Furthermore the ventral anchors are shorter than those of all other species of Ligophorus reported in the Gulf of Mexico and Caribbean Sea. In addition, the zoogeographical records of Ligophorus spp. on the M. cephalus species complex are briefly reviewed and updated. PMID:26408603

  2. New nuclear markers and exploration of the relationships among Serraniformes (Acanthomorpha, Teleostei): the importance of working at multiple scales.

    PubMed

    Lautredou, A-C; Motomura, H; Gallut, C; Ozouf-Costaz, C; Cruaud, C; Lecointre, G; Dettai, A

    2013-04-01

    We explore the relationships within Serraniformes (Li et al., 2009) using a dense taxon sampling and seven nuclear markers. Six had already used been for teleost phylogeny (IRBP, MC1R, MLL4, Pkd1, Rhodopsin, and RNF213) at other scales, and one (MLL2) is new. The results corroborate the composition of Serraniformes described in previous publications (some Gasterosteiformes, Perciformes and Scorpaeniformes). Within the clade, Notothenioidei and Zoarcoidei are each monophyletic. Cottoidei was not monophyletic due to placement of the genus Ebinania (Psychrolutidae). Our independent data confirm the sister-group relationship of Percophidae and Notothenioidei as well as the division of Platycephaloidei in four different groups (Bembridae, Platycephalidae, Hoplichthyidae and Peristediidae with Triglidae). Within Cottoidei, Liparidae and Cyclopteridae formed a clade associated with Cottidae, the genus Cottunculus (Psychrolutidae), and Agonidae. Serranidae and Scorpaenidae are not monophyletic, with the Serranidae divided in two clades (Serraninae and Epinephelinae/Anthiinae) and Scorpaenidae including Caracanthidae and the genus Ebinania (Psychrolutidae). We discuss some morphological characters supporting clades within the Scorpaenidae. PMID:23306305

  3. An evaluation of fossil tip-dating versus node-age calibrations in tetraodontiform fishes (Teleostei: Percomorphaceae).

    PubMed

    Arcila, Dahiana; Alexander Pyron, R; Tyler, James C; Ortí, Guillermo; Betancur-R, Ricardo

    2015-01-01

    Time-calibrated phylogenies based on molecular data provide a framework for comparative studies. Calibration methods to combine fossil information with molecular phylogenies are, however, under active development, often generating disagreement about the best way to incorporate paleontological data into these analyses. This study provides an empirical comparison of the most widely used approach based on node-dating priors for relaxed clocks implemented in the programs BEAST and MrBayes, with two recently proposed improvements: one using a new fossilized birth-death process model for node dating (implemented in the program DPPDiv), and the other using a total-evidence or tip-dating method (implemented in MrBayes and BEAST). These methods are applied herein to tetraodontiform fishes, a diverse group of living and extinct taxa that features one of the most extensive fossil records among teleosts. Previous estimates of time-calibrated phylogenies of tetraodontiforms using node-dating methods reported disparate estimates for their age of origin, ranging from the late Jurassic to the early Paleocene (ca. 150-59Ma). We analyzed a comprehensive dataset with 16 loci and 210 morphological characters, including 131 taxa (95 extant and 36 fossil species) representing all families of fossil and extant tetraodontiforms, under different molecular clock calibration approaches. Results from node-dating methods produced consistently younger ages than the tip-dating approaches. The older ages inferred by tip dating imply an unlikely early-late Jurassic (ca. 185-119Ma) origin for this order and the existence of extended ghost lineages in their fossil record. Node-based methods, by contrast, produce time estimates that are more consistent with the stratigraphic record, suggesting a late Cretaceous (ca. 86-96Ma) origin. We show that the precision of clade age estimates using tip dating increases with the number of fossils analyzed and with the proximity of fossil taxa to the node under assessment. This study suggests that current implementations of tip dating may overestimate ages of divergence in calibrated phylogenies. It also provides a comprehensive phylogenetic framework for tetraodontiform systematics and future comparative studies. PMID:25462998

  4. Evolutionary history of Otophysi (Teleostei), a major clade of the modern freshwater fishes: Pangaean origin and Mesozoic radiation

    PubMed Central

    2011-01-01

    Background Freshwater harbors approximately 12,000 fish species accounting for 43% of the diversity of all modern fish. A single ancestral lineage evolved into about two-thirds of this enormous biodiversity (? 7900 spp.) and is currently distributed throughout the world's continents except Antarctica. Despite such remarkable species diversity and ubiquity, the evolutionary history of this major freshwater fish clade, Otophysi, remains largely unexplored. To gain insight into the history of otophysan diversification, we constructed a timetree based on whole mitogenome sequences across 110 species representing 55 of the 64 families. Results Partitioned maximum likelihood analysis based on unambiguously aligned sequences (9923 bp) confidently recovered the monophyly of Otophysi and the two constituent subgroups (Cypriniformes and Characiphysi). The latter clade comprised three orders (Gymnotiformes, Characiformes, Siluriformes), and Gymnotiformes was sister to the latter two groups. One of the two suborders in Characiformes (Characoidei) was more closely related to Siluriformes than to its own suborder (Citharinoidei), rendering the characiforms paraphyletic. Although this novel relationship did not receive strong statistical support, it was supported by analyzing independent nuclear markers. A relaxed molecular clock Bayesian analysis of the divergence times and reconstruction of ancestral habitats on the timetree suggest a Pangaean origin and Mesozoic radiation of otophysans. Conclusions The present timetree demonstrates that survival of the ancestral lineages through the two consecutive mass extinctions on Pangaea, and subsequent radiations during the Jurassic through early Cretaceous shaped the modern familial diversity of otophysans. This evolutionary scenario is consistent with recent arguments based on biogeographic inferences and molecular divergence time estimates. No fossil otophysan, however, has been recorded before the Albian, the early Cretaceous 100-112 Ma, creating an over 100 million year time span without fossil evidence. This formidable ghost range partially reflects a genuine difference between the estimated ages of stem group origin (molecular divergence time) and crown group morphological diversification (fossil divergence time); the ghost range, however, would be filled with discoveries of older fossils that can be used as more reasonable time constraints as well as with developments of more realistic models that capture the rates of molecular sequences accurately. PMID:21693066

  5. Isolation and characterization of 13 polymorphic microsatellite loci in Hypostomus ancistroides (Teleostei, Loricariidae) and cross-amplification in related species.

    PubMed

    Galindo, B A; Ferreira, D G; Almeida, F S; Carlsson, J; Sofia, S H

    2015-06-01

    This study details 13 novel polymorphic microsatellite loci in the armoured catfish Hypostomus ancistroides, and assesses their utility for population genetic studies. The analysis of 30 individuals revealed a total of 99 different alleles (ranging from two to 15 alleles per locus), with an average of 762 alleles per locus, with observed and expected heterozygosities ranging from 0103 to 0931 and from 0102 to 0906, respectively. One of the 13 loci showed significant deviations from Hardy-Weinberg equilibrium, probably due to the presence of null alleles, inferred from the excess of homozygotes. PMID:25912318

  6. The eels of the genus Nettenchelys, with description of a new species from Taiwan (Teleostei: Anguilliformes: Nettastomatidae).

    PubMed

    Smith, David G; Lin, James; Chen, Hong-Ming; Pogonoski, John J

    2015-01-01

    The species of the genus Nettenchelys are summarized. Nine species are recognized on the basis of adult specimens: Nettenchelys dionisi Brito, N. erroriensis Karmovskaya, N. exoria Bhlke & Smith, N. gephyra Castle & Smith, N. inion Smith & Bhlke, N. paxtoni Karmovskaya, N. proxima new species, N. pygmaea Smith & Bhlke, and N. taylori Alcock. Another species, N. bellottii (D'Ancona) is based on a larva. Nettenchelys gephyra is redescribed on the basis of additional specimens from northeastern Taiwan, Indonesia and Australia. Nettenchelys proxima new species is described from a specimen from southwestern Taiwan. Nettenchelys sp. reported by Uyeno & Sasaki (1983) is found to be a specimen of Facciolella. Information on larvae is updated based on new knowledge of the genus. PMID:26701595

  7. Phylogeny and biogeography of 91 species of heroine cichlids (Teleostei: Cichlidae) based on sequences of the cytochrome b gene.

    PubMed

    Pérez, Gustavo A Concheiro; Rícan, Oldrich; Ortí, Guillermo; Bermingham, Eldredge; Doadrio, Ignacio; Zardoya, Rafael

    2007-04-01

    Heroini constitute the second largest tribe of Neotropical cichlids and show their greatest diversity in Mesoamerica. Although heroine species are morphologically and ecologically very diverse, they were all historically assigned to one single genus, Cichlasoma that was never formally revised from a phylogenetic point of view. Here, we present the most comprehensive molecular phylogeny of the tribe Heroini to date, based on the complete DNA sequence of the mitochondrial gene cytochrome b, and the analysis of 204 individuals representing 91 species. Phylogenetic analyses did not support the monophyly of heroines because the genus Pterophyllum was placed as the sister group of all remaining heroines plus cichlasomatines. However, the recovered relative position of Pterophyllum was without strong statistical support. Within the remaining heroines, Hyspelecara and Hoplarchus are recovered with low support in a basal position with respect to a clade that includes Heros, Uaru, Mesonauta, and Symphysodon, and the circumamazonian (CAM) heroines. The first clade is restricted to South America. The largest clade of heroines, the CAM heroines, include more than 85% of the species within the tribe. This clade is mostly Mesoamerican, but also contains four species found in the Greater Antilles (Nandopsis), and three genera found in South America (the 'Heros' festae group, Australoheros, and Caquetaia). Up to eight major lineages can be recovered within the CAM heroines, but the phylogenetic relationships among them remain unresolved. Two large suprageneric groups can be distinguished, the amphilophines and the herichthyines. The amphilophines include Amphilophus, Archocentrus, Hypsophrys, Neetroplus, Parachromis, Petenia, and five additional unnamed genera (the 'Heros' istlanus group, the 'Amphilophus' calobrensis group, the 'Heros' urophthalmus group, the 'Heros' wesseli group, and the 'Heros' sieboldii group). The herichthyines include the crown-group herichthyines (Herichthys, Theraps, Vieja, and Paratheraps) and the genera Tomocichla, Herotilapia, and Thorichthys, together with three unnamed genera (the 'Heros' umbriferus group, the 'Heros' grammodes group, and the 'Heros' salvini group). Amphilophines are prevalent in southern Mesomerica south of the Motagua fault. Herichthyines have basal linages in Central America, whereas crown-group herichthyines and three related genera are found north from the Motagua fault. At least two independent origins are required to explain current Mesoamerican heroine distribution. Dispersal of heroines from South America into Mesoamerica was dated between 24 and 16 million years ago (MYA) based on geological calibrations and on standard fish mitochondrial cytochrome b rates, respectively. These datings cannot be reconciled with currently known geological evidence, and the existence of a connection between Central America and South America in the Miocene needs to be postulated in order to explain the origins of Mesoamerican heroine lineages. However, our datings agree with those estimated for the dispersal of other secondary freshwater fishes (Rivulidae, Synbranchus) into Mesoamerica, and predate the invasion of primary freshwater fishes by at least 10 myr. PMID:17045493

  8. Composition and structure of the parasite faunas of cod, Gadus morhua L. (Teleostei: Gadidae), in the North East Atlantic

    PubMed Central

    Perdiguero-Alonso, Diana; Montero, Francisco E; Raga, Juan Antonio; Kostadinova, Aneta

    2008-01-01

    Background Although numerous studies on parasites of the Atlantic cod, Gadus morhua L. have been conducted in the North Atlantic, comparative analyses on local cod parasite faunas are virtually lacking. The present study is based on examination of large samples of cod from six geographical areas of the North East Atlantic which yielded abundant baseline data on parasite distribution and abundance. Materials and Methods A total of 826 fish was sampled in the Baltic, Celtic, Irish and North seas, Icelandic waters and Trondheimsfjord (Norway) in 2002 (spring and autumn) and 2003 (spring). The gills and internal organs (oesophagus, stomach, intestine, pyloric caeca, liver, heart, spleen, gall bladder and gonads) were examined for macroparasites following a standardised protocol. The taxonomic consistency of the identification was ensured thorough the entire study. Results We discuss some problems in parasite identification, outline the composition of the parasite faunas in cod in the six North East Atlantic regions, provide novel data on parasite prevalence and abundance and a comparative assessment of the structure of the regional parasite faunas with respect to the higher-level taxonomic groupings, host specificity and zoogeographical distribution of the parasites. Altogether 57 different parasite forms were found including seven new host records (Diclidophora merlangi, Rhipidocotyle sp., Fellodistomum sp., Steringotrema sp., Cucullanus sp., Spinitectus sp., and Chondracanthus ornatus). The predominant groups of cod parasites were trematodes (19 species) and nematodes (13 species) including larval anisakids which comprised 58.2% of the total number of individuals. Conclusion Our study reveals relatively rich regional parasite faunas in cod from the North East Atlantic which are dominated by generalist parasites with Arcto-Boreal distribution. Further, it provides more detailed data on the distribution in the North East Atlantic of the majority of cod parasites which may serve as baselines for future studies on the effect of climate change. Based on the faunal comparisons, predictions can be made in relation to the structure and diversity of the parasite communities in the North East Atlantic regions studied. PMID:18638387

  9. Aspects of the biology of the sandsmelt Atherina boyeri Risso, 1810 (Teleostei: Atherinidae) at Oldbury-upon-Severn, Gloucestershire, England

    NASA Astrophysics Data System (ADS)

    Palmer, C. J.; Culley, M. B.

    1983-02-01

    The age structure, annual growth, length-weight relationship, reproduction and other aspects of the general biology in Boyer's sandsmelt, Atherina boyeri, from the Severn estuary, have been studied for the period 1974-1977. The results are compared with those found in previous investigations of A. boyeri from more southerly waters.

  10. Reproductive biology of Ilisha elongata (Teleostei: Pristigasteridae) in Ariake Sound, Japan: Implications for estuarine fish conservation in Asia

    NASA Astrophysics Data System (ADS)

    Zhang, Jie; Takita, Toru; Zhang, Chunguang

    2009-01-01

    Elongate ilisha ( Ilisha enlongata) is a commercially important species that contributes to clupeoid fisheries in Asian countries. In the present study, the reproductive biology of I. elongata in Ariake Sound, Japan is determined for the first time. Six maturity stages were described using ovarian and testicular histology throughout the annual cycle. The spawning season in Ariake Sound lasts from May to July, with peak spawning activity in May and June. Age at first maturity was estimated to be 2 years, with a few exceptions of 1 year in well-developed males. Ovaries that contained both tertiary yolk oocytes and postovulatory follicles occurred from late May to late July, indicating that I. elongata is a multiple spawner. The size-frequency distribution of oocytes provided evidence for its multiple spawning and accuracy of the fecundity estimates. The batch fecundity of this species was estimated at between 22,200 and 270,900 eggs per individual, increasing with age between two and six years. The present findings on the reproductive strategy of I. elongata in Ariake Sound are generally consistent with those in temperate or subtropical populations, but quite different from those of tropical population where first maturation occurs around 200 days and life spans are shorter, with a maximum age less than 3 years. The conservation implications of this reproductive strategy in a harsh, variable environment in Asian countries are also discussed.

  11. Development of the splanchnocranium in Prochilodus argenteus (Teleostei: Characiformes) with a discussion of the basal developmental patterns in the Otophysi.

    PubMed

    Carvalho, Murilo; Vari, Richard P

    2015-02-01

    Development of the mandibular, hyoid and gill arches, which constitute the splanchnocranium, are described for Prochilodus argenteus, order Characiformes, one of the basal lineages of the Otophysi. Development was examined from just hatched larvae through juveniles using whole specimens cleared and counterstained for cartilage and bone as well as histological preparations. Observations are compared with the developmental trends reported for Cypriniformes, the basalmost clade of the Otophysi. Shortened developmental sequences for Prochilodus compared to the cypriniform Catostomus were discovered in the ontogeny of the ceratohyals, ceratobranchials 1-5, epibranchials 1-4 and the symplectic portion of the hyosymplectic. Prochilodus also differs from Catostomus in having the basihyal plus the anterior copula appearing at different stages of ontogeny rather than simultaneously. Contrary to previous assumptions, developmental information indicates that hypobranchial 4 as well as likely basibranchial 5 are present in Prochilodus. Various developmental patterns in Prochilodus considered basal for the Otophysi, the predominant component of the Ostariophysi, are likely conserved from patterns prevalent in basal groups in the Actinopterygii. PMID:25595854

  12. Scavenger receptors facilitate protein transport in the trophotaenial placenta of the goodeid fish, Ameca splendens (Teleostei: Atheriniformes).

    PubMed

    Schindler, Joachim F

    2003-10-01

    In the goodeid placental analogue, trophotaeniae provide extraembryonic gut-derived exchange surfaces. Ameca splendens embryos possess endocytosing trophotaeniae that are capable of absorbing a dazzling array of proteinaceous substances. The iron core protein, native ferritin (NF), and several radioiodinated proteinaceous substances were used to study ligand and binding site pathways in the trophotaenial absorptive cells (TACs). Time sequence analysis of NF trafficking indicated an exclusively lysosomal pathway. Binding to TACs of NF was completely inhibitable by proteins containing multiple lysine residues such as apoferritin, bovine serum albumin (BSA), human transferrin (HTf), fetuin, hemoglobin, myoglobin, cytochrome c, ubiquitin, parvalbumin as well as the random copolymers, poly(Glu,Lys,Tyr)6:3:1 and poly(D-Glu,D-Lys)6:4. Peptide hormones and pepsin that contains only one lysine residue did not produce inhibitory effects. Radiolabels such as (125)I-BSA, (125)I-HTf and (125)I-poly(Glu,Lys,Tyr) bound to trophotaeniae in a specific saturable manner. Any two proteins were shown to hinder one another in getting hold of a binding site. Concentration-dependent (125)I-BSA binding and Scatchard analysis of the data revealed both low- and medium-affinity binding with apparent dissociation constants, K(d)s, of 3.4 x 10(-5) M and 2 x 10(-7) M, respectively. Binding of NF and radioiodinated proteins was inhibited in the presence of a large excess of L-Lys, D-Lys, and several dipeptides containing Lys. Both Ca(2+)-depletion and low pH dramatically reduced the TACs' capacity to bind proteins. The effects of acidotropic agents included a reversible loss of surface protein binding sites, tremendous vacuolation, and the arrest of lysosomal degradation. Collectively, present results demonstrate that TACs bind and absorb multiple proteinaceous substances through a mechanism satisfying the criteria of receptor-mediated endocytosis. It is concluded that scavenger protein binding sites are used to ingest proteins for lysosomal degradation, helping to meet the embryos' amino acid requirement. PMID:12975808

  13. Experimentally induced pigment changes in small African 'Barbus' (Teleostei: Cyprinidae): Synonymy of 'Barbus' amphigramma and 'Barbus' taitensis with 'Barbus' paludinosus

    USGS Publications Warehouse

    Farm, Brian P.

    2001-01-01

    Pigmentation in fishes is known to be variable both among individuals of a species and within individuals over time. Use of pigment characters for taxonomic diagnoses must, therefore, be carefully considered. I present experimental evidence showing that pigment characters previously considered diagnostic for three small African 'Barbus' species may differ between living and preserved specimens and that lasting changes in these characters can be induced experimentally by placing fishes in a different, less turbid environment. Lateral line pigmentation and presence of a spot on the caudal peduncle showed significant changes that resulted in different species identifications before and after the experiment. These pigment patterns are thereby shown to be labile, nontrenchant characters having little or no diagnostic utility. 'Barbus' amphigramma Boulenger, 1903, and 'Barbus' taitensis Gu??nther, 1894, are thus shown to be junior synonyms of 'Barbus' paludinosus Peters, 1852.

  14. Ellipsomyxa syngnathi sp. n. (Myxozoa, Myxosporea) in the pipefish Syngnathus typhle and S. rostellatus (Teleostei, Syngnathidae) from Denmark.

    PubMed

    Køie, Marianne; Karlsbakk, Egil

    2009-11-01

    A new species Ellipsomyxa syngnathi sp. n. (Myxozoa) is described from Syngnathus typhle L. and Syngnathus rostellatus Nilsson, 1855 (Syngnathidae), using spore morphology and SSU rDNA sequence data. Monosporic plasmodia develop in the internal gallbladder wall. The ellipsoid myxospore has two pyriform polar capsules which discharge at opposite sides some distance from both sutural line and spore ends. The myxospore mainly differs from that of Ellipsomyxa gobii Køie (Folia Parasitol 50:269-271, 2003) in being monosporic and in having the sutural line oblique to the thickness axis. Zschokkella mugilis Sitjá-Bobadilla and Alvarez-Pellitero (J Euk Microbiol 40:755-764, 1993) is transferred to Ellipsomyxa as Ellipsomyxa mugilis comb. n. PMID:19727823

  15. Further evidence for the invasion and establishment of Pterois volitans (Teleostei: Scorpaenidae) along the Atlantic Coast of the United States

    USGS Publications Warehouse

    Meister, H.S.; Wyanski, D.M.; Loefer, J.K.; Ross, S.W.; Quattrini, A.M.; Sulak, K.J.

    2005-01-01

    We document the continued population expansion of red lionfish, Pterois volitans, the first documented successful introduction of an invasive marine fish species from the western Pacific to Atlantic coastal waters of the United States. Red lionfish are indigenous to the Indo-Pacific and have apparently established one or more breeding populations on reefs off the southeastern United States. Fifty-nine specimens, most presumably adult red lionfish, were documented or collected on live-bottom reefs off North Carolina, South Carolina, and Florida, and on a manmade structure off Georgia. Observation/collection depths and bottom water temperatures for these fish ranged from 40-99 m and 13.8-24.4??C, respectively. Eleven juvenile lionfish, believed to be expatriated from southeastern waters, were collected in estuaries along the coast of Long Island, NY, at depths of 0-5 m and water temperatures ranging from 13.8-16.5??C. Twelve of the total 70 specimens collected or observed were positively identified as red lionfish. Based on histological assessment of gonad tissue, two reproductively-active males and one immature female were collected. The life history of red lionfish, especially their reproductive biology and food habits, should be investigated along the east coast of the US to determine the potential impacts of this species on ecosystems they have invaded.

  16. Myxobolus myleus n. sp. infecting the bile of the Amazonian freshwater fish Myleus rubripinnis (Teleostei: Serrasalmidae): morphology and pathology.

    PubMed

    Azevedo, Carlos; So Clemente, Srgio Carmona; Casal, Graa; Matos, Patrcia; Alves, ngela; Al-Quraishy, Saleh; Matos, Edilson

    2012-07-01

    Myxobolus myleus n. sp. is described from the gall-bladder of the freshwater fish Myleus rubripinnis collected near the city of Oriximin in the Amazon System, Brazil. The spores obtained from the bile contained two equal symmetrical and smooth valves, each forming the spore wall. The spores were large, with a cone-like form, a semi spherical basal contour and measured (in ?m) 19.3 0.5 (n = 25) 8.3 0.5 (n = 25) 4.0 0.3 (n = 15). The apical end of the spores contained two elongate, equal and pointed conical polar capsules measuring 13.2 0.4 ?m (n = 25) in length and 3.0 0.3 ?m (n = 15) in width, each having a slightly tapering polar filament with 19 to 21 turns. The polar capsules were extended below at about 4/5 of the total length of the spores. The sporoplasm was binucleate and contained some sporoplasmosomes. All infected fish presented hypertrophy of the gall-bladder due to presence of the brownish parasite floating in the bile. In this paper we describe this new species of myxosporean based on light and ultrastructural observations, together with its associated pathology. PMID:22711511

  17. Taste preferences and taste thresholds to classical taste substances in the carnivorous fish, kutum Rutilus frisii kutum (Teleostei: Cyprinidae).

    PubMed

    Goli, Sheyda; Jafari, Valiollah; Ghorbani, Rassol; Kasumyan, Alexander

    2015-03-01

    The objective of this study was to compare the taste preferences in the closely related sympatric fish species with different feeding patterns. For this purpose, palatability for four classical taste substances was evaluated for carnivorous kutum Rutilus frisii kutum and the results were compared with the taste preferences of the omnivorous roach Rutilus rutilus which had been studied earlier. In addition, the threshold concentration and the dose-response relationship of the most palatable tastants were evaluated and the ability of kutum to differentiate food with tastants in different concentrations was estimated. It was found that citric acid significantly increases the agar gel pellet consumption within the range of concentrations from 0.01M to 0.52M; the pellets with a concentration of 0.026M were the most palatable. The pellet consumption is significantly different if the concentration of citric acid in the pellets differs more than two times. The absolute threshold concentration is 0.01M, or 2.74μg of citric acid per pellet. Sucrose and NaCl have deterrent taste at the highest concentrations tested (0.29 and 1.73M, respectively). Both substances are palatable at 10 times lower concentrations and become indifferent after further gradual decrease in their concentration. CaCl2 decreases the pellets consumption at 0.9M but is an indifferent tastant at lower concentrations (0.45, 0.09 and 0.045M). The number of rejections and repeated grasps of a food pellet is fewness and is not related to the pellet's palatability, while the retention time of pellet in the oral cavity positively and highly correlates with the pellet's palatability. Kutum have opposite taste preferences for most substances tested in comparison with the roach. It indicates that the taste preferences mediated by the oral taste receptors are different in closely related sympatric fish displayed diet divergences. PMID:25497081

  18. Mitochondrial phylogeny of Chinese barred species of the cyprinid genusAcrossocheilus Oshima, 1919 (Teleostei: Cypriniformes) and its taxonomic implications.

    PubMed

    Yuan, Le-Yang; Liu, Xiao-Xiang; Zhang, E

    2015-01-01

    Sequences from the mitochondrial control region of 14 putative species of Acrossocheilus (Cyprinidae) were examined to elucidate phylogenetic relationships within species of the barred group in that genus. Phylogenetic reconstructions were generated using three tree-building methods: maximum parsimony, maximum likelihood, and Bayesian inference. The resultant phylogenies were consistent with monophyly of the majority of the morphologically recognized species. However, mitochondrial DNA sequence evidence is incongruent with monophyly of A. fasciatus, as currently conceived. This species occurs only in the upper Qiantang-Jiang basin in Zhejiang and Anhui provinces, and coastal rivers in the Zhejiang Province. The species formerly recognized as A. paradoxus from Zhejiang Province is A. fasciatus. The specimens previously reported as A. fasciatus from river basins in Fujian Province are misidentified A. wuyiensis. The barred group of Acrossocheilus is shown to be polyphyletic. Acrossocheilus is restricted to the barred species here placed in "Clade II," containing A. paradoxus and relatives. Separate generic status is recommended for A. monticola and for A. longipinnis and their closest relatives, although more information on phylogenetic relationships based on multiple genes is required to develop robust phylogenetic hypotheses and diagnoses. Masticbarbus Tang, 1942 is available for A. longipinnis and three allied species (A. iridescens, A. microstomus and A. lamus). PMID:26701558

  19. The complete mitochondrial genome of the gnomefish Scombrops boops (Teleostei, Perciformes, Scombropidae) from the Pacific Ocean off the Japanese Islands.

    PubMed

    Tsunashima, Tadasuke; Itoi, Shiro; Abe, Koko; Takigawa, Tomoyuki; Inoue, Satoshi; Kozen, Takahiro; Ono, Naoto; Noguchi, Shunsuke; Nakai, Shizuko; Takai, Noriyuki; Huang, Ming-Chih; Sugita, Haruo

    2016-01-01

    The complete mitochondrial genome of the gnomefish Scombrops boops was determined by a PCR-based method. The total length of mitochondrial DNA (mtDNA) was 16,517?bp, including 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and one control region. The mitochondrial gene arrangement of the gnomefish mtDNA was identical to those of typical teleosts. This is the first report of the complete mitochondrial genome of a member of the Scombropidae family and will be useful for the development of molecular tools for ecological research. PMID:25484172

  20. Three cone opsin genes determine the properties of the visual spectra in the Japanese anchovy, Engraulis japonicus (Engraulidae, Teleostei).

    PubMed

    Kondrashev, Sergei L; Miyazaki, Taeko; Lamash, Nina E; Tsuchiya, Tohru

    2013-03-15

    A complement of cone visual pigments was identified in the Japanese anchovy Engraulis japonicus, one of the engraulid fish species that has a retina specialized for polarization and color vision. The nature of the chromophore bound to opsin proteins was investigated using high performance liquid chromatography. The opsin genes were then cloned and sequenced, and the absorption spectra of different types of cones were obtained by microspectrophotometry. Two green (EJ-RH2-1, EJ-RH2-2) and one red (EJ-LWS) cone opsin genes were identified and are presumably related to the vitamin A1-based visual pigments (i.e. rhodopsins) with ?max values of 492, 474 and 512 nm, respectively. The long and short cones from the ventro-temporal retinal zone consisted of a pure population of RH2 class gene-based pigments (?max=492 nm). The long and short cones from other retinal areas and the lateral components of the triple cones possessed a mixture of RH2 and LWS class gene-based pigments that exhibited a ?max of ~502 nm. The central component of the triple cones contained only RH2 class gene-based pigments (?max=474 nm). Thus, E. japonicus possesses a middle-wave range of spectral sensitivity and acquires different color vision systems in distinct visual fields. PMID:23197087

  1. Apistogramma ortegai (Teleostei: Cichlidae), a new species of cichlid fish from the Ampyiacu River in the Peruvian Amazon basin.

    PubMed

    Britzke, Ricardo; Oliveira, Claudio; Kullander, Sven O

    2014-01-01

    Apistogramma ortegai, new species, is described from small streams tributaries of the Ampiyacu River near Pebas, in eastern Peru. It belongs to the Apistogramma regani species group and is distinguished from all other species of Apistogramma by the combination of contiguous caudal spot to bar 7, presence of abdominal stripes, short dorsal-fin lappets in both sexes, absence of vertical stripes on the caudal fin, and reduced number of predorsal and prepelvic scales. PMID:25283927

  2. Biochemical responses over time in common carp Cyprinus carpio (Teleostei, Cyprinidae) during fed supplementation with ?-lipoic acid.

    PubMed

    Enamorado, Alain D; Martins, Atila C; Flores, Juliana A; Tesser, Marcelo Borges; Caldas, Sergiane S; Primel, Ednei G; Monserrat, Jos Maria

    2015-10-01

    The current study aimed to evaluate the influence of lipoic acid (LA) supplementation (439.846.71 mg LA/kg feed) on antioxidants responses throughout the time in intestine, liver and muscle of juvenile common carp Cyprinus carpio. Two experimental groups were fed during four weeks with a diet with or without LA. Glutathione-S-transferase (GST) activity, glutathione (GSH) content, antioxidant capacity against peroxyl radicals (ACAP) and lipid peroxidation (TBARS) were evaluated in these organs. Also, a technique to measure protein disulfide bonds and sulfhydryl groups was optimized for intestine samples. GST activity was significantly higher (p<0.05) in intestine after two weeks of supplementation. GSH content was also significantly higher (p<0.05) in intestine, liver and muscle of fish fed with LA after two and three weeks, respectively. Total capacity antioxidant against peroxyl radicals was significantly increased (p<0.05) in the muscle of animals fed with LA after the fourth week. Concentration of disulfide bonds was higher in the intestine of fish fed with LA but this group also showed higher concentration of sulfhydryl groups (p<0.05). It is concluded that supplementation with LA is a safe strategy to induce antioxidant responses and improves the antioxidant status in different organs of common carp. Two week of supplementation are required to induce antioxidant responses in intestine and liver and three week for muscle. PMID:26037328

  3. Pseudorhabdosynochus regius n. sp. (Monogenea, Diplectanidae) from the mottled grouper Mycteroperca rubra (Teleostei) in the Mediterranean Sea and Eastern Atlantic

    PubMed Central

    Chaabane, Amira; Neifar, Lassad; Justine, Jean-Lou

    2015-01-01

    Pseudorhabdosynochus regius n. sp. is described from the gills of the mottled grouper Mycteroperca rubra caught off Senegal, Tunisia and Libya (type-locality: off Dakar, Senegal). The species is distinguished from its congeners by the structure of its sclerotised vagina (length 2635?m), which exhibits a trumpet in continuity with the primary canal, a straight primary canal, and primary and secondary chambers included in a common sclerotised mass along the primary canal. The species is also characterised by small squamodiscs (length 2040?m) with 1011 rows of rodlets. Its closest relatives (based on the structure of the sclerotised vagina) are species mostly found in the Mediterranean Sea and parasites on species of Mycteroperca. A second species of Pseudorhabdosynochus Yamaguti, 1958 is reported from the same host and localities but not described. A list of diplectanids from groupers in the Mediterranean Sea is provided. We point out that a recent article was not compliant with the new Article 8.5.3 of the International Code of Zoological Nomenclature; for this reason, three species, P. nhatrangensis Dang, Bristow, Schander & Berland, 2013, P. vietnamensis Dang et al., 2013 and P. brunei Dang et al., 2013, are invalid. PMID:25674913

  4. Pseudorhabdosynochus regius n. sp. (Monogenea, Diplectanidae) from the mottled grouper Mycteroperca rubra (Teleostei) in the Mediterranean Sea and Eastern Atlantic.

    PubMed

    Chaabane, Amira; Neifar, Lassad; Justine, Jean-Lou

    2015-01-01

    Pseudorhabdosynochus regius n. sp. is described from the gills of the mottled grouper Mycteroperca rubra caught off Senegal, Tunisia and Libya (type-locality: off Dakar, Senegal). The species is distinguished from its congeners by the structure of its sclerotised vagina (length 26-35 ?m), which exhibits a trumpet in continuity with the primary canal, a straight primary canal, and primary and secondary chambers included in a common sclerotised mass along the primary canal. The species is also characterised by small squamodiscs (length 20-40 ?m) with 10-11 rows of rodlets. Its closest relatives (based on the structure of the sclerotised vagina) are species mostly found in the Mediterranean Sea and parasites on species of Mycteroperca. A second species of Pseudorhabdosynochus Yamaguti, 1958 is reported from the same host and localities but not described. A list of diplectanids from groupers in the Mediterranean Sea is provided. We point out that a recent article was not compliant with the new Article 8.5.3 of the International Code of Zoological Nomenclature; for this reason, three species, P. nhatrangensis Dang, Bristow, Schander & Berland, 2013, P. vietnamensis Dang et al., 2013 and P. brunei Dang et al., 2013, are invalid. PMID:25674913

  5. Characterization of hepatic growth hormone binding sites in two fish species, Gillichthys mirabilis (Teleostei) and Acipenser transmontanus (Chondrostei).

    PubMed

    Tarpey, J F; Nicoll, C S

    1985-10-01

    To obtain information on the presence of growth hormone (GH) receptors in liver of nonmammalian vertebrates the specific binding of 125I-bovine growth hormone (bGH) to liver membranes of seven species representing the major groups was studied by radioreceptor assay. A substantial degree of specific binding was detected with sturgeon (Acipenser transmontanus) liver membranes and a much lower amount was detected on hepatic membranes of Gillichthys mirabilis. No significant specific binding was detected on liver membranes of pigeon, turtle, bullfrog, tilapia, or leopard shark. Gillichthys and sturgeon liver membranes were further characterized and compared with hepatic membranes from male rabbits. The sturgeon and Gillichthys membranes showed binding that was dependent upon time, temperature, pH, and membrane concentration. Scatchard analysis of the binding of 125I-bGH to sturgeon and rabbit membranes revealed both high and low affinity binding sites. The high affinity sites had KA values of 3.1 X 10(11) and 1.0 X 10(11) M-1, and capacities of 12 and 50 fmol/mg protein, respectively. Membranes from Gillichthys liver contained only a single class of binding sites with a KA of 6.7 X 10(9) M-1 and a binding capacity of 49 fmol/mg. Hormonal specificity of the sturgeon and Gillichthys hepatic binding sites was studied using methionyl-human GH (met-hGH), ovine prolactin (oPRL), and a crude preparation of sturgeon (st)GH. The met-hGH and stGH inhibited the binding of 125I-bGH to sturgeon liver membranes while only met-hGH displaced labeled bGH from Gillichthys liver membranes. One microgram of oPRL did not significantly inhibit 125I-bGH binding in either membrane assay. Based on these studies, sturgeon hepatic GH receptors seem to be more like those of nonprimate mammals than those of teleosts. Our results, in conjunction with the data of J. N. Fryer (Gen. Comp. Endocrinol. 39, 123-130 (1979)), indicate that considerable evolutionary divergence has occurred among teleost hepatic GH receptors. Thus, vertebrate GH receptors seem to have undergone at least as much evolution as has the hormone itself. PMID:2996975

  6. Pluvial Drainage Patterns and Holocene Desiccation Influenced the Genetic Architecture of Relict Dace, Relictus solitarius (Teleostei: Cyprinidae).

    PubMed

    Houston, Derek D; Evans, R Paul; Shiozawa, Dennis K

    2015-01-01

    Changing drainage patterns have played a significant role in the evolution of western North American aquatic taxa. Relict dace, Relictus solitarius, is a Great Basin endemic cyprinid with a native range that is restricted to four valleys in eastern Nevada. Relictus solitarius now occupies spring systems that are the remnants of Pleistocene-era pluvial lakes, although it may have occurred in the area for much longer. Here we use mitochondrial DNA sequence data to assess range-wide genetic diversity of R. solitarius, and to estimate divergence times to determine whether pluvial drainages played an important role in shaping intraspecific genetic diversity. Genetic diversification within R. solitarius began during the early to mid-Pleistocene, separating populations within two sets of valleys (Butte/Ruby and Goshute/Steptoe). Additional diversification in each of the two sets of valleys occurred more recently, in the mid- to late-Pleistocene. Holocene desiccation has further isolated populations, and each population sampled contains unique mtDNA haplotypes. Pluvial drainage patterns did contribute to the genetic structure observed within R. solitarius, but most of the intraspecific diversification does not appear to be associated with the Last Glacial Maximum. Holocene desiccation has also contributed to the observed genetic structure. The relict dace populations we sampled are all unique, and we recommend that future management efforts should strive to preserve as much of the genetic diversity as possible. PMID:26394395

  7. Cytogenetic analysis of B chromosomes in one population of the fish Moenkhausia sanctaefilomenae (Steindachner, 1907) (Teleostei, Characiformes)

    PubMed Central

    Voltolin, Diogo Teruo Hashimoto Tatiana Aparecida; Paes, Ana Danyelle Noitel Valim de Arruda; Foresti, Fausto; Bortolozzi, Jehud; Porto-Foresti, Fbio

    2012-01-01

    Abstract The aim of this study was to characterize cytogenetically one population of the fish Moenkhausia sanctaefilomenae (Steindachner, 1907), with emphasis on the analysis of B chromosomes. The nucleolar activity in the B microchromosomes was characterized, and an analysis of mitotic instability of these microchromosomes was accomplished. The results showed a diploid chromosome number of 50 chromosomes. In all individuals, we observed the presence of B microchromosomes with intra- and inter-individual variability. The analysis of the nucleolus organizing regions (NORs) by silver nitrate staining demonstrated multiple NORs. We observed active sites of ribosomal DNA in the B microchromosomes, with a frequency of 20% in the analyzed cells, which shows gene activity in these chromosomal elements. The analysis of constitutive heterochromatin patterns showed that the B microchromosomes are heterochromatic or euchromatic, which demonstrates differentiation of DNA composition between these genomic elements. The calculation of the mitotic instability index implied that B chromosomes in this species might be in a final stage of instability. PMID:24260658

  8. Henneguya cynoscioni sp. n. (Myxosporea: Bivalvulida), an agent of severe cardiac lesions in the spotted seatrout, Cynoscion nebulosus (Teleostei: Sciaenidae).

    PubMed

    Dykov, Iva; de Buron, Isaure; Roumillat, William A; Fiala, Ivan

    2011-09-01

    A new myxosporean species, Henneguya cynoscioni sp. n., is described from the spotted seatrout, Cynoscion nebulosus (Cuvier) (Sciaenidae) as a causative agent of cardiac henneguyosis. This new myxosporean species is characterized by the morphology of spores and the sequence of SSU rDNA. Examination of 227 spotted seatrout from four South Carolina estuaries in 2008-2010 revealed a 33.5% total prevalence of H. cynoscioni. Henneguya cynoscioni produces lesions in the bulbus arteriosus, its specific site of infection. The severity of lesions and their impact on the bulbus arteriosus is proportional to the number of plasmodial stages developing in this segment of the heart, being most pronounced in host reaction directed against spores liberated from plasmodia. PMID:22053614

  9. The involvement of gonadotropins and gonadal steroids in the ovulatory dysfunction of the potamodromous Salminus hilarii (Teleostei: Characidae) in captivity.

    PubMed

    Moreira, Renata Guimares; Honji, Renato Massaaki; Melo, Renato Garcia; de Moraes Narcizo, Amanda; Amaral, Juliane Suzuki; de Carvalho Arajo, Ronaldo; Hilsdorf, Alexandre Wagner Silva

    2015-12-01

    Potamodromous teleosts that require migration to reproduce show dysfunctions that block ovulation and spawning while in captivity. To understand the physiological basis of these reproductive dysfunctions, follicle-stimulating hormone b subunit (fshb) and luteinizing hormone b subunit (lhb) gene expression analyses by real-time quantitative PCR, together with measurements of estradiol (E 2), 17?-hydroxyprogesterone (17?-OHP) and 17?,20?-dihydroxy-4-pregnen-3-one (17?,20?-DHP) levels, were carried out throughout the reproductive cycle of the potamodromous Salminus hilarii. The following reproductive stages were evaluated in captive and wild females: previtellogenic (PV), advanced maturation/mature (AM) and regression/spent (REG/SPENT). In the wild females, fshb expression decreased from the PV to the AM stage, and the opposite pattern was detected for E 2, which increased from the PV to the AM stage. fshb was expressed at lower levels in captive than in wild females, and this difference did not change during the reproductive cycle. lhb expression also increased from the PV to the AM stage in both groups, but the wild females at the AM and REG/SPENT stages showed higher lhb expression levels than the captive females. The concentrations of 17?-OHP did not change during the reproductive cycle, and the levels were higher in the captive than in the wild females at all reproductive stages. 17?,20?-DHP levels did not change between wild and captive females. However, in captive females, the transition from PV to AM stage was followed by an increase in 17?,20?-DHP levels. These data indicate that dysfunctions in the gonadotropins and steroids synthesis pathways cause the ovulation failure in captive S. hilarii. PMID:26183262

  10. DNA barcoding at riverscape scales: assessing biodiversity among fishes of the genus Cottus (Teleostei) in northern Rocky Mountain streams.

    PubMed

    Young, Michael K; McKelvey, Kevin S; Pilgrim, Kristine L; Schwartz, Michael K

    2013-07-01

    There is growing interest in broad-scale biodiversity assessments that can serve as benchmarks for identifying ecological change. Genetic tools have been used for such assessments for decades, but spatial sampling considerations have largely been ignored. Here, we demonstrate how intensive sampling efforts across a large geographical scale can influence identification of taxonomic units. We used sequences of mtDNA cytochrome c oxidase subunit 1 and cytochrome b, analysed with maximum parsimony networks, maximum-likelihood trees and genetic distance thresholds, as indicators of biodiversity and species identity among the taxonomically challenging fishes of the genus Cottus in the northern Rocky Mountains, USA. Analyses of concatenated sequences from fish collected in all major watersheds of this area revealed eight groups with species-level differences that were also geographically circumscribed. Only two of these groups, however, were assigned to recognized species, and these two assignments resulted in intraspecific genetic variation (>2.0%) regarded as atypical for individual species. An incomplete inventory of individuals from throughout the geographical ranges of many species represented in public databases, as well as sample misidentification and a poorly developed taxonomy, may have hampered species assignment and discovery. We suspect that genetic assessments based on spatially robust sampling designs will reveal previously unrecognized biodiversity in many other taxa. PMID:23496857

  11. Postglacial recolonization of eastern Blacknose Dace,Rhinichthys atratulus(Teleostei: Cyprinidae), through the gateway of New England

    PubMed Central

    Tipton, Michelle L; Gignoux-Wolfsohn, Sarah; Stonebraker, Phoebe; Chernoff, Barry

    2011-01-01

    During the last ice age, much of North America far south as 40°N was covered by glaciers (Hewitt 2000). About 20,000 years ago, as the glaciers retreated, the hydrologic landscape changed dramatically creating waterways for fish dispersal. The number of populations responsible for recolonization and the regions from which they recolonized are unknown for many freshwater fishes living in New England and southeastern Canada. The Blacknose Dace,Rhinichthys atratulus, is one of the freshwater fish species that recolonized this region. We hypothesize that the earliest deglaciated region, modern-day Connecticut, was recolonized byR. atratulusvia a single founding event by a single population. In this paper, we test this hypothesis phylogenetically with regard to the major drainage basins within Connecticut. The mitochondrial DNA exhibits low nucleotide diversity, high haplotype diversity, and a dominant haplotype found across the state. A small percentage of individuals in the Housatonic drainage basin, however, share a haplotype with populations in New York drainage basins, a haplotype not found elsewhere in Connecticut's drainage basins. We calculated a range for the rate of divergence for NADH dehydrogenase subunit 2 (nd2) and control region (ctr) of 4.43–6.76% and 3.84–8.48% per million years (my), respectively. While this range is higher than the commonly accepted rate of 2% for mitochondrial DNA, these results join a growing list of publications finding high rates of divergence for various taxa (Peterson and Masel 2009). The data support the conclusion that Connecticut as a whole was recolonized initially by a single founding event that came from a single refugium. Subsequently, the Housatonic basin alone experienced a secondary recolonization event. PMID:22393505

  12. Species profiles: Life history and environmental requirements of coastal fishes and invertebrates (South Florida): King mackerel and Spanish mackerel. [Scomberomorus cavalla; Scomberomorus maculatus

    SciTech Connect

    Godcharles, M.F.; Murphy, M.D.

    1986-06-01

    This Species Profile on king and Spanish mackerel summarizes the taxonomy, morphology, distribution, life history, fishery descriptions, ecological role, and environmental requirements of these coastal pelagic fish to assist environmental impact assessment. King and Spanish mackerel support major commercial and sport fisheries in south Florida. In 1974 to 1983, Gulf of Mexico and Atlantic commercial landings of king mackerel declined from 10.4 to 4.3 million lb.; Spanish mackerel have fluctuated between 4.9 to 17.4 million lb. Both inhabit coastal waters, but Spanish mackerel are generally found closer to beaches and in outer estuarine waters. Both species feed principally on estuarine-dependent species. They are highly migratory, exhibiting seasonal migrations to winter feeding grounds off south Florida and summer spawning/feeding grounds in the northern Gulf of Mexico and off the Atlantic coast of the Southeastern US. Spawning occurs from March/April through September/October between the middle and Outer Continental Shelf (35 to 183 mi) for king mackerel and the inner shelf (12 to 34 mi) for Spanish mackerel. King mackerel reach sexual maturity in their 3rd and 4th years and Spanish, between their 2nd and 3rd. Female king mackerel live longer and grow larger and faster than males. Spanish mackerel live to 8 years; females also grow faster than males. King and Spanish mackerel feed principally on schooling fishes. Larvae and juveniles of both species are prey to little tunny and dolphin; adults are prey for sharks and bottlenose dolphin. Temperature and salinity are important factors regulating mackerel distribution.

  13. Does heterospecific seminal fluid reduce fecundity in interspecific copulation between seed beetles?

    PubMed

    Kyogoku, Daisuke; Sota, Teiji

    2015-01-01

    Reproductive interference through mating between related species can cause fitness reduction and affect population dynamics of the interacting species. In experimental matings between two seed beetles, Callosobruchus chinensis and Callosobruchus maculatus, C. maculatus females, but not C. chinensis females, suffer from significant loss of fecundity when conspecific mating is followed by heterospecific mating. We hypothesized that male traits associated with sexual conflict, which are often harmful to females, pleiotropically affect fitness of heterospecific females through interspecific mating. We examined the effect of ejaculate of C. chinensis males on C. maculatus females as the cause of the fecundity loss in C. maculatus females due to interspecific copulation. We found that frequent interspecific copulation occurred between C. maculatus females and C. chinensis males, but not between C. chinensis females and C. maculatus males, resulting in frequent interspecific ejaculate transfer from C. chinensis males to C. maculatus females. However, injection of the extract from C. chinensis male reproductive organs into C. maculatus females did not significantly affect C. maculatus fecundity compared with saline injection, indicating that the effect of the heterospecific ejaculate transfer on fecundity is negligible. We suggest that other harmful male traits such as genital spines of C. chinensis males are mainly responsible for the fecundity reduction in C. maculatus females that have experienced interspecific mating. PMID:25497118

  14. Biodiversity of the Betta smaragdina (Teleostei: Perciformes) in the northeast region of Thailand as determined by mitochondrial COI and nuclear ITS1 gene sequences.

    PubMed

    Kowasupat, Chanon; Panijpan, Bhinyo; Laosinchai, Parames; Ruenwongsa, Pintip; Phongdara, Amornrat; Wanna, Warapond; Senapin, Saengchan; Phiwsaiya, Kornsunee

    2014-12-01

    In Thailand, there are currently five recognized species members of the bubble-nesting Betta genus, namely Betta splendens, B. smaragdina, B. imbellis, B. mahachaiensis and B. siamorientalis. In 2010, we indicated the possibility, based on COI barcoding evidence, that there might be two additional species, albeit cryptic, related to the type-locality B. smaragdina in some provinces in the northeast of Thailand. In the present study, after a more extensive survey of the northeast, and phylogenetic analyses based on COI and ITS1 sequences, the B. smaragdina group may be composed of at least 3 cryptic species members. The phylogenetic positions of these B. smaragdina group members in the bubble-nesting bettas' tree together with those of their congeners have been consolidated by better DNA sequence quality and phylogenetic analyses. With a better supported tree, the species statuses of B. siamorientalis and the Cambodian B. smaragdina-like fish, B. stiktos, are also confirmed. PMID:25606392

  15. Southeast Asian mouth-brooding Betta fighting fish (Teleostei: Perciformes) species and their phylogenetic relationships based on mitochondrial COI and nuclear ITS1 DNA sequences and analyses

    PubMed Central

    Panijpan, Bhinyo; Kowasupat, Chanon; Laosinchai, Parames; Ruenwongsa, Pintip; Phongdara, Amornrat; Senapin, Saengchan; Wanna, Warapond; Phiwsaiya, Kornsunee; Kühne, Jens; Fasquel, Frédéric

    2014-01-01

    Fighting fish species in the genus Betta are found in several Southeast Asian countries. Depending on the mode of paternal care for fertilized eggs and hatchlings, various species of the betta fish are classified as mouth brooders or nest builders whose members in turn have been grouped according to their similarities mainly in morphology. The mouth brooders as well as some nest builders involved in the present study include fishes discovered and identified subsequent to previous reports on species groupings and their positions on phylogenetic trees based on DNA sequences that differ from those used by us in this study. From the mitochondrial COI gene and nuclear ITS1 gene sequences and more accurate analyses we conclude that the following members of the mouth-brooding pairs, named differently previously, are virtually identical, viz the Betta prima–Betta pallida pair and Betta ferox–Betta apollon pair. The Betta simplex, hitherto believed to be one species, could possibly be genetically split into 2 distinct species. In addition, several other established type-locality fishes could harbor cryptic species as judged by genetic differences. Assignments of fish species to groups reported earlier may have to be altered somewhat by the present genetic findings. We propose here a new Betta fish phylogenetic tree which, albeit being similar to the previous ones, is clearly different from them. Our gene-based evidence also leads to assignments of some fishes to new species groups and alters the positions of some species on the new phylogenetic tree, thus implying different ancestral relationships. PMID:25606468

  16. Southeast Asian mouth-brooding Betta fighting fish (Teleostei: Perciformes) species and their phylogenetic relationships based on mitochondrial COI and nuclear ITS1 DNA sequences and analyses.

    PubMed

    Panijpan, Bhinyo; Kowasupat, Chanon; Laosinchai, Parames; Ruenwongsa, Pintip; Phongdara, Amornrat; Senapin, Saengchan; Wanna, Warapond; Phiwsaiya, Kornsunee; Kühne, Jens; Fasquel, Frédéric

    2014-12-01

    Fighting fish species in the genus Betta are found in several Southeast Asian countries. Depending on the mode of paternal care for fertilized eggs and hatchlings, various species of the betta fish are classified as mouth brooders or nest builders whose members in turn have been grouped according to their similarities mainly in morphology. The mouth brooders as well as some nest builders involved in the present study include fishes discovered and identified subsequent to previous reports on species groupings and their positions on phylogenetic trees based on DNA sequences that differ from those used by us in this study. From the mitochondrial COI gene and nuclear ITS1 gene sequences and more accurate analyses we conclude that the following members of the mouth-brooding pairs, named differently previously, are virtually identical, viz the Betta prima-Betta pallida pair and Betta ferox-Betta apollon pair. The Betta simplex, hitherto believed to be one species, could possibly be genetically split into 2 distinct species. In addition, several other established type-locality fishes could harbor cryptic species as judged by genetic differences. Assignments of fish species to groups reported earlier may have to be altered somewhat by the present genetic findings. We propose here a new Betta fish phylogenetic tree which, albeit being similar to the previous ones, is clearly different from them. Our gene-based evidence also leads to assignments of some fishes to new species groups and alters the positions of some species on the new phylogenetic tree, thus implying different ancestral relationships. PMID:25606468

  17. Biodiversity of the Betta smaragdina (Teleostei: Perciformes) in the northeast region of Thailand as determined by mitochondrial COI and nuclear ITS1 gene sequences☆

    PubMed Central

    Kowasupat, Chanon; Panijpan, Bhinyo; Laosinchai, Parames; Ruenwongsa, Pintip; Phongdara, Amornrat; Wanna, Warapond; Senapin, Saengchan; Phiwsaiya, Kornsunee

    2014-01-01

    In Thailand, there are currently five recognized species members of the bubble-nesting Betta genus, namely Betta splendens, B. smaragdina, B. imbellis, B. mahachaiensis and B. siamorientalis. In 2010, we indicated the possibility, based on COI barcoding evidence, that there might be two additional species, albeit cryptic, related to the type-locality B. smaragdina in some provinces in the northeast of Thailand. In the present study, after a more extensive survey of the northeast, and phylogenetic analyses based on COI and ITS1 sequences, the B. smaragdina group may be composed of at least 3 cryptic species members. The phylogenetic positions of these B. smaragdina group members in the bubble-nesting bettas' tree together with those of their congeners have been consolidated by better DNA sequence quality and phylogenetic analyses. With a better supported tree, the species statuses of B. siamorientalis and the Cambodian B. smaragdina-like fish, B. stiktos, are also confirmed. PMID:25606392

  18. The Gyrodactylus (Monogenea, Gyrodactylidae) parasite fauna of freshwater sand gobies (Teleostei, Gobioidei) in their centre of endemism, with description of seven new species.

    PubMed

    Vanhove, Maarten P M; Economou, Alcibiades N; Zogaris, Stamatis; Giakoumi, Sofia; Zanella, Davor; Volckaert, Filip A M; Huyse, Tine

    2014-02-01

    While Gobioidei comprises showcases of (adaptive) radiation, the scientific interest they yielded did not ensure full understanding of goby biodiversity. Even in a well-studied region like Europe, wide knowledge gaps remain. Sand gobies represent one of the few clades whose monogenean parasites have been thoroughly studied. However, in the Balkans, part of the sand gobies' centre of endemism, these parasites were unstudied. We focus on Greek and Croatian freshwater gobies. From five sand goby species, the first parasites are reported, describing seven new Gyrodactylus species. Economidichthys pygmaeus harbours Gyrodactylus benedeni sp. n. and Gyrodactylus dorlodoti sp. n. Its congener E. trichonis hosts G. meelkopae sp. n. Knipowitschia milleri was found to host G. charon sp. n., K. thessala is infected by G. bios sp. n., and K. croatica by G. douglasadamsi sp. n. and G. hellemansi sp. n. Gyrodactylus bubyri was found on its type host K. caucasica. A diverse parasite fauna is expected for a region known for its biodiversity and endemism. The contribution of parasites to species richness in such hotspots is overlooked. The observed species richness per host is rather low compared to the better-studied eastern Atlantic sand gobies. Host vicariance is considered to mediate parasite specificity in this fauna. Some new flatworm species display unique morphological features, such as the remarkable size of the marginal hook sickle proper compared to its foot in the Economidichthys parasites, or a characteristically kinked marginal hook sickle in G. douglasadamsi sp. n. These features reflect their hosts' endemism in the Balkans. PMID:24288050

  19. Are rapids a barrier for floodplain fishes of the Amazon basin? A demographic study of the keystone floodplain species Colossomamacropomum (Teleostei: Characiformes).

    PubMed

    Farias, Izeni Pires; Torrico, Juan Pablo; Garca-Dvila, Carmen; Santos, Maria da Conceio Freitas; Hrbek, Tomas; Renno, Jean-Franois

    2010-09-01

    We investigated demographic history and population structuring of Colossoma macropomum sampled from 14 localities in the Amazon basin and the Bolivian sub-basin; the two basins are separated by a series of 16 rapids. Although genetically differentiated, IMa analyses suggest non-zero bi-directional migration rates, and inter-basin divergence of approximately 17 thousand years ago. Analyses in BEAST indicated that Bolivian C. macropomum has been demographically stable except for a moderate population increase in the last 12 thousand years, while Amazonian C. macropomum has been experiencing demographic growth over the last 350 thousand years, resulting in approximately one order of magnitude increase in coalescent N(e). PMID:20362063

  20. Leis' conundrum: homology of the clavus of the ocean sunfishes. 1. Ontogeny of the median fins and axial skeleton of Monotrete leiurus (Teleostei, Tetraodontiformes, Tetraodontidae).

    PubMed

    Britz, Ralf; Johnson, G David

    2005-10-01

    We describe the ontogeny of the axial skeleton and median fins of the Southeast Asian freshwater puffer Monotrete leiurus, based on a reared developmental series. Most elements of the axial skeleton in M. leiurus arise in membrane bone. Only the base of the anterior three neural arches, the base of the hemal arches of the third preural centrum, the neural and hemal arches and spines of the second preural centrum, the parhypural, the two hypural plates, and the single epural are preformed in cartilage. In contrast to most teleosts, the proximal-middle radials of the dorsal and anal fins are upright and symmetrical and their distal tips coalesce during development to form a deep band of cartilage, from which the spherical distal radials are spatially separated. PMID:15549688

  1. First insights into the diversity of gill monogeneans of 'Gnathochromis' and Limnochromis (Teleostei, Cichlidae) in Burundi: do the parasites mirror host ecology and phylogenetic history?

    PubMed

    Kmentov, Nikol; Gelnar, Milan; Koblmller, Stephan; Vanhove, Maarten P M

    2016-01-01

    Monogenea is one of the most species-rich groups of parasitic flatworms worldwide, with many species described only recently, which is particularly true for African monogeneans. For example, Cichlidogyrus, a genus mostly occurring on African cichlids, comprises more than 100 nominal species. Twenty-two of these have been described from Lake Tanganyika, a famous biodiversity hotspot in which many vertebrate and invertebrate taxa, including monogeneans, underwent unique and spectacular radiations. Given their often high degrees of host specificity, parasitic monogeneans were also used as a potential tool to uncover host species relationships. This study presents the first investigation of the monogenean fauna occurring on the gills of endemic 'Gnathochromis' species along the Burundese coastline of Lake Tanganyika. We test whether their monogenean fauna reflects the different phylogenetic position and ecological niche of 'Gnathochromis' pfefferi and Gnathochromis permaxillaris. Worms collected from specimens of Limnochromis auritus, a cichlid belonging to the same cichlid tribe as G. permaxillaris, were used for comparison. Morphological as well as genetic characterisation was used for parasite identification. In total, all 73 Cichlidogyrus individuals collected from 'G.' pfefferi were identified as C. irenae. This is the only representative of Cichlidogyrus previously described from 'G.' pfefferi, its type host. Gnathochromis permaxillaris is infected by a species of Cichlidogyrus morphologically very similar to C. gillardinae. The monogenean species collected from L. auritus is considered as new for science, but sample size was insufficient for a formal description. Our results confirm previous suggestions that 'G.' pfefferi as a good disperser is infected by a single monogenean species across the entire Lake Tanganyika. Although G. permaxillaris and L. auritus are placed in the same tribe, Cichlidogyrus sp. occurring on G. permaxillaris is morphologically more similar to C. irenae from 'G.' pfefferi, than to the Cichlidogyrus species found on L. auritus. Various evolutionary processes, such as host-switching or duplication events, might underlie the pattern observed in this particular parasite-host system. Additional samples for the Cichlidogyrus species occuring on G. permaxillaris and L. auritus are needed to unravel their evolutionary history by means of (co-)phylogenetic analyses. PMID:26855869

  2. Comparisons of the genetic structure of Squalius populations (Teleostei, Cyprinidae) from rivers with contrasting histories, drainage areas and climatic conditions based on two molecular markers.

    PubMed

    Almada, V; Sousa-Santos, C

    2010-11-01

    The genetic structure of Squalius populations from Portuguese Atlantic- and Mediterranean-type streams (assigned to six distinct morphoclimatic regions) was compared using sequences of the cytb and beta-actin genes. The drainage area was significantly correlated to all the genetic diversity indices, pointing to the need to control for this effect in comparing populations with different histories and paleoecologies. A significant correlation was also found between genetic diversity and the morphoclimatic regions to which the rivers were assigned, with the highest diversity in warmer, lower latitude, Mediterranean-type streams. This relationship was not due to idiosyncratic characteristics of the clades compared. When the drainage area and phylogenetic effects were removed, the southern Mediterranean streams harboured significantly more genetic diversity even when compared with much larger northern streams. It is argued that these results are likely caused both by the metapopulation structure of the Mediterranean streams and by the severe reduction or local extinction of populations in the northern rivers during glaciations. PMID:20736072

  3. Changes along the male reproductive axis in response to social context in a gonochoristic gobiid, Zosterisessor ophiocephalus (Teleostei, Gobiidae), with alternative mating tactics.

    PubMed

    Scaggiante, Marta; Grober, Matthew S; Lorenzi, Varenka; Rasotto, Maria B

    2004-12-01

    Sexual selection has given rise, in several taxa, to intrasexual variation in male phenotype. While evolutionary studies have provided explanations of the adaptive function of this dramatic male phenotypic diversity, the proximate control of its expression has still to be completely understood. Several observations, primarily from sex-changing species, indicated a major role of social interactions in reproductive axis regulation and consequently in the expression of alternative male phenotypes. Here we documented changes along the male reproductive axis in response to social context in a gonochoristic species, the grass goby Zosterisessor ophiocephalus, where fully functional alternative male mating tactics appear to be expressed as an ontogenetic gradient. In the grass goby, larger and older males dig a nest and perform parental care, while smaller males sneak fertilization during territorial male spawning. Territorial males are characterized by a higher number of gonadotropin-releasing hormone (GnRH) neurons in forebrain preoptic area, smaller testes, larger seminal vesicles, and viscous ejaculates that last longer and contain fewer sperm than those of sneakers. To experimentally investigate the role of social factors in inducing changes along the male reproductive axis, sneakers were tested in two different situations: nesting alone or with ripe females. Sneakers that mated and performed parental care showed dramatic changes in brain, reproductive apparatus morphology, and ejaculate traits. GnRH-immunoreactive cells in forebrain preoptic area increased in number, reaching values typical of wild-caught parental males. Testes size decreased while seminal vesicle size increased and ejaculates showed lower sperm densities. These results were discussed within the framework of the social transduction hypothesis, which predicts that social experience should mediate, through a cascade of internal processes, shifts between morphs throughout life. PMID:15555503

  4. An invasive lineage of sculpins, Cottus sp. (Pisces, Teleostei) in the Rhine with new habitat adaptations has originated from hybridization between old phylogeographic groups

    PubMed Central

    Nolte, Arne W; Freyhof, Jörg; Stemshorn, Kathryn C; Tautz, Diethard

    2005-01-01

    Fish abundance surveys in the Rhine system have shown in the past two decades that there is a rapid upriver invasion of a freshwater sculpin of the genus Cottus. These fish are found in habitats that are atypical for the known species Cottus gobio, which is confined to small cold streams within the Rhine drainage. Phylogeographic analysis based on mitochondrial haplotypes and diagnostic single nucleotide polymorphisms indicates that the invasive sculpins are hybrids between two old lineages from the River Scheldt drainage and the River Rhine drainage, although it is morphologically more similar to the Scheldt sculpins. Most importantly, however, the invasive population possesses a unique ecological potential that does not occur in either of the source populations from the Rhine or the Scheldt, which allows the colonization of new habitats that have previously been free of sculpins. Microsatellite analysis shows that the new lineage is genetically intermediate between the old lineages and that it forms a distinct genetic group across its whole expansion range. We conclude that hybridization between long separated groups has lead to the fast emergence of a new, adaptationally distinct sculpin lineage. PMID:16243698

  5. A new species of Ituglanis from the Rio Xingu Basin, Brazil, and the evolution of pelvic fin loss in trichomycterid catfishes (Teleostei: Siluriformes: Trichomycteridae).

    PubMed

    Datovo, Aléssio

    2014-01-01

    A new species of the trichomycterid catfish genus Ituglanis is described from the Rio Curuá, Rio Xingu basin, Rio Amazonas drainage, Brazil. Ituglanis apteryx, new species, is promptly distinguished from congeners, except some specimens of I. parahybae (Eigenmann), by the absence of pelvic fins, girdle, and muscles. The new species differs from I. parahybae in the pattern of the cephalic laterosensory system; the absence of a posterior cranial fontanel; the presence of an epural; and the number of branchiostegal rays, ribs, and vertebrae. Ituglanis apteryx is one among the several trichomycterids lacking pelvic fins. Analysis reveals that pelvic fin loss independently evolved several times during the trichomycterid radiation. PMID:24869879

  6. Karyotypic diversity and evolutionary trends in the Neotropical catfish genus Hypostomus Lacépède, 1803 (Teleostei, Siluriformes, Loricariidae)

    PubMed Central

    Alves, Anderson Luis; de Borba, Rafael Splendore; Oliveira, Claudio; Mauro Nirchio; Granado, Angel; Foresti, Fausto

    2012-01-01

    Abstract The family Loricariidae with 813 nominal species is one of the largest fish families of the world. Hypostominae, its more complex subfamily, was recently divided into five tribes. The tribe Hypostomini is composed of a single genus, Hypostomus Lacépède, 1803, which exhibits the largest karyotypic diversity in the family Loricariidae. With the main objective of contributing to a better understanding of the relationship and the patterns of evolution among the karyotypes of Hypostomus species, cytogenetic studies were conducted in six species of the genus from Brazil and Venezuela. The results show a great chromosome variety with diploid numbers ranging from 2n=68 to 2n=76, with a clear predominance of acrocentric chromosomes. The Ag-NORs are located in terminal position in all species analyzed. Three species have single Ag-NORs (Hypostomus albopunctatus (Regan, 1908), Hypostomus prope plecostomus (Linnaeus, 1758), and Hypostomus prope paulinus (Ihering, 1905)) and three have multiple Ag-NORs (Hypostomus ancistroides (Ihering, 1911), Hypostomus prope iheringi (Regan, 1908), and Hypostomus strigaticeps (Regan, 1908)). In the process of karyotype evolution of the group, the main type of chromosome rearrangements was possibly centric fissions, which may have been facilitated by the putative tetraploid origin of Hypostomus species. The relationship between the karyotype changes and the evolution in the genus is discussed. PMID:24260683

  7. Life-history traits of temperate and thermophilic barracudas (Teleostei: Sphyraenidae) in the context of sea warming in the Mediterranean Sea.

    PubMed

    Villegas-Hernndez, H; Muoz, M; Lloret, J

    2014-06-01

    This study indicated that the life-history traits of European barracuda Sphyraena sphyraena are apparently better suited to their environmental conditions compared to the more physically restricted life-history traits of the yellow-mouth barracuda Sphyraena viridensis, which co-habit the north-western Mediterranean Sea. The latter thermophilic species has a considerably higher reproductive potential as it invests its energy reserves in larger numbers of hydrated eggs per spawning batch. This would favour its population growth rates within the study area, especially if sea warming continues, in which case it is likely that the spawning phenology of this species would give it an advantage. PMID:24890410

  8. Repeatability of clades as a criterion of reliability: a case study for molecular phylogeny of Acanthomorpha (Teleostei) with larger number of taxa.

    PubMed

    Chen, Wei-Jen; Bonillo, Céline; Lecointre, Guillaume

    2003-02-01

    Although much progress has been made recently in teleostean phylogeny, relationships among the main lineages of the higher teleosts (Acanthomorpha), containing more than 60% of all fish species, remain poorly defined. This study represents the most extensive taxonomic sampling effort to date to collect new molecular characters for phylogenetic analysis of acanthomorph fishes. We compiled and analyzed three independent data sets, including: (i) mitochondrial ribosomal fragments from 12S and 16s (814bp for 97 taxa); (ii) nuclear ribosomal 28S sequences (847bp for 74 taxa); and (iii) a nuclear protein-coding gene, rhodopsin (759bp for 86 taxa). Detailed analyses were conducted on each data set separately and the principle of taxonomic congruence without consensus trees was used to assess confidence in the results as follows. Repeatability of clades from separate analyses was considered the primary criterion to establish reliability, rather than bootstrap proportions from a single combined (total evidence) data matrix. The new and reliable clades emerging from this study of the acanthomorph radiation were: Gadiformes (cods) with Zeioids (dories); Beloniformes (needlefishes) with Atheriniformes (silversides); blenioids (blennies) with Gobiesocoidei (clingfishes); Channoidei (snakeheads) with Anabantoidei (climbing gouramies); Mastacembeloidei (spiny eels) with Synbranchioidei (swamp-eels); the last two pairs of taxa grouping together, Syngnathoidei (aulostomids, macroramphosids) with Dactylopteridae (flying gurnards); Scombroidei (mackerels) plus Stromatoidei plus Chiasmodontidae; Ammodytidae (sand lances) with Cheimarrhichthyidae (torrentfish); Zoarcoidei (eelpouts) with Cottoidei; Percidae (perches) with Notothenioidei (Antarctic fishes); and a clade grouping Carangidae (jacks), Echeneidae (remoras), Sphyraenidae (barracudas), Menidae (moonfish), Polynemidae (threadfins), Centropomidae (snooks), and Pleuronectiformes (flatfishes). PMID:12565036

  9. Modifications of the falciform process in the eye of beloniformes (Teleostei: Atherinomorpha): evolution of a curtain-like septum in the eye.

    PubMed

    Reckel, Frank; Melzer, Roland R

    2004-04-01

    In order to comparatively analyze curtain-like septa in the eyes of visually orientated "close-to-surface-predators" among atherinomorph teleosts, we examined the eyes of 24 atherinomorph species under a binocular microscope with regard to the falciform process and related structures in the vitreous cavity. Additionally, falciform process samples were analyzed by transmission electron microscopy. All the studied representatives of the Cyprinodontiformes and Atheriniformes, and of one of the beloniform suborder, Adrianichthyioidei, possess a "typical" processus falciformis. In the eyes of the representatives of the other beloniform suborder, Belonoidei, however, pigmented structures that originate in the region of the optic disc and protrude into the vitreous cavity were noted. In the Hemiramphidae (halfbeaks) and Exocoetidae (flying fishes) these pigmented structures have a more cone-like shape, whereas in the Belonidae (needlefishes) and Scomberesocidae (sauries) horizontally oriented heavily pigmented curtain-like septa occur that divide the vitreous cavity dorsoventrally. It is suggested that the "typical" processus falciformis represents a plesiomorphic feature within the Atherinomorpha, whereas the pigmented modifications of the falciform process must be seen as a synapomorphic character state of the Belonoidei. The curtain-like septum of the Belonidae and Scomberesocidae might have evolved from the cone-like structures that are found in the Exocoetoidea. The functional significance of the pigmented structures in the eye is as yet not clear, except for the curtain-like septum found in Belonidae. It might play a role in visual orientation near the water surface at Snell's window. PMID:15052593

  10. Morphology of the jaw, suspensorial, and opercle musculature of Beloniformes and related species (Teleostei: Acanthopterygii), with a special reference to the m. adductor mandibulae complex.

    PubMed

    Werneburg, Ingmar

    2015-01-01

    The taxon Beloniformes represents a heterogeneous group of teleost fishes that show an extraordinary diversity of jaw morphology. I present new anatomical descriptions of the jaw musculature in six selected beloniforms and four closely related species. A reduction of the external jaw adductor (A1) and a changed morphology of the intramandibular musculature were found in many Beloniformes. This might be correlated with the progressively reduced mobility of the upper and lower jaw bones. The needlefishes and sauries, which are characterised by extremely elongated and stiffened jaws, show several derived characters, which in combination enable the capture of fish at high velocity. The ricefishes are characterised by several derived and many plesiomorphic characters that make broad scale comparisons difficult. Soft tissue characters are highly diverse among hemiramphids and flying fishes reflecting the uncertainty about their phylogenetic position and interrelationship. The morphological findings presented herein may help to interpret future phylogenetic analyses using cranial musculature in Beloniformes. PMID:25755920

  11. A revision of the Rutilus complex from Mediterranean Europe with description of a new genus, Sarmarutilus, and a new species, Rutilus stoumboudae (Teleostei: Cyprinidae).

    PubMed

    Bianco, Pier Giorgio; Ketmaier, Valerio

    2014-01-01

    By combining morphology, ecology, biology, and biogeography with the available molecular (sequence variation of the entire mitochondrial cytochrome b gene; cyt-b) and karyology data, the taxonomy of several species of the Rutilus complex inhabiting southern Europe is revised. Rutilus stoumboudae, new species, is described from Lake Volvi, Greece. It differs from Rutilus rutilus in possessing more total GR and less branched rays in both dorsal and anal fins and in its placement in the cyt-b based phylogeny of the genus. The resurrected genus Leucos Heckel, 1843 (type species Leucos aula, Bonaparte, 1841), which according to molecular data diverged from Rutilus more than 5 million years ago, during the Messinian salinity crisis, includes five species of small size, without spinous tubercles on scales and head in reproductive males, pharyngeal teeth formula 5-5, and all show a preference for still waters. Leucos aula is the Italian species endemic in the Padany-Venetian district: L. basak is widespread in Croatia, Albania, Montenegro and former Yugoslav Republic of Macedonia (FYROM); L. albus, recently described from Lake Skadar, Montenegro, is also found in rivers Moraca and Zeta (Montenegro). L. albus differs from L. basak, its closest relative, in having more scales on the LL and less anal-fin rays; L. panosi is endemic to the western-Greece district, and L. ylikiensis is endemic to lakes Yliki and Paralimni in eastern Greece (introduced in Lake Volvi). Among the nominal species examined, Rutilus karamani, R. ohridanus, R. prespensis and R. prespensis vukovici are all junior synonyms of Leucos basak. Rutilus vegariticus is definitively regarded as junior synonym for R. rutilus. Sarmarutilus n.gen. is a monotypic genus, with Sarmarutilus rubilio as the type species. According to phylogenetic data, Sarmarutilus rubilio is basal to a cluster of species that includes Leucos basak, L. albus, L. aula, L. panosi and L. ylikiensis. Sarmarutilus possibly evolved in pre-Messinian time, in the Lago Mare, entered the Mediterranean area during the Messinian Lago Mare phase of the Mediterranean Sea and survived only in the Tuscany- Latium district. This genus differs from Leucos in having large pearl organs on the central part of head and body scales in mature males and for the habitat preference, being a riverine-adapted species. It differs from Rutilus in pharyngeal teeth formula (5-5 in Sarmarutilus and 6-5 in Rutilus), size (small in Sarmarutilus and large in Rutilus) and for the preferential habitat (riverine vs. still water). Finally, lectotypes for Leucos basak, Leucos aula, and Sarmarutilus rubilio are designated. PMID:25082046

  12. Juvenile didymozoids of the types, Torticaecum and Neotorticaecum (Didymozoidae: Digenea), from new marine fish hosts (Pisces: Teleostei) in the neotropical region of Brazil.

    PubMed

    Felizardo, N N; Justo, M C; Knoff, M; Fonseca, M C G; Pinto, R M; Gomes, D C

    2011-09-01

    From December 2006 to March 2008, 60 specimens of Paralichthys isosceles and 25 specimens of P. patagonicus were investigated for helminths. One hundred and sixty-nine digeneans were recovered and parasites were identified as juvenile didymozoids of two types. Torticaecum and Neotorticaecum were found in 48 of the 60 P. isosceles (80%) and 10 of the 25 P. patagonicus (40%). Torticaecum and Neotorticaecum are reported for the first time in fish in South America (Brazil), found in the Atlantic Ocean. Morphometrics and illustrations are presented. PMID:20854704

  13. Demographic structure and life history traits of the common goby Pomatoschistus microps (Teleostei, Gobiidae) in a Mediterranean coastal lagoon (Rhône River delta, France)

    NASA Astrophysics Data System (ADS)

    Pampoulie, Christophe

    2001-12-01

    Demographic structure and life history traits of the common goby Pomatoschistus microps were investigated in a brackish water lagoon of the Rhône River delta (Mediterranean Sea, southern France). The size frequency distribution and gonadosomatic index indicated that three different age groups occurred and reproduced successively in the lagoon, resulting in a long spawning period from March to September and a high investment in reproduction. This high investment in reproduction, which contrasts with that found in other mostly northern European populations, probably relates to the unpredictability of the goby's environmental conditions.

  14. A new, mesophotic Coryphopterus goby (Teleostei, Gobiidae) from the southern Caribbean, with comments on relationships and depth distributions within the genus.

    PubMed

    Baldwin, Carole C; Robertson, D Ross

    2015-01-01

    A new species of western Atlantic Coryphopterus is described from mesophotic depths off Curaçao, southern Caribbean. Coryphopteruscurasub sp. n., is similar to Coryphopterusdicrus in, among other features, having two prominent pigment spots of roughly equal intensity on the pectoral-fin base, the pelvic fins fused to form a disk, and no pelvic frenum. The two species can be differentiated by body depth (shallower in Coryphopteruscurasub at origin of dorsal fin and caudal peduncle); differences in the pigmentation on the head, trunk, and basicaudal region; and usually by total number of rays (spinous plus soft) in the second dorsal fin (10-11, usually 11, in Coryphopteruscurasub, 10 in Coryphopterusdicrus). Coryphopteruscurasub differs from other Coryphopterus species that have a prominent pigment spot on the lower portion of the pectoral-fin base (Coryphopteruspunctipectophorus and Coryphopterusvenezuelae) in, among other features, lacking a pelvic frenum. Coryphopteruscurasub was collected between 70 and 80 m, the deepest depth range known for the genus. Collections of Coryphopterusvenezuelae at depths of 65-69 m extend the depth range of that species by approximately 50 m. Mitochondrial cytochrome c oxidase subunit I (COI) data corroborate the recognition of Coryphopteruscurasub as a distinct species but do not rigorously resolve its relationships within the genus. A revised key to the western Atlantic species of Coryphopterus is presented. PMID:26257572

  15. Status of Gobiosoma (Teleostei: Gobiidae) from Brazil: description of a new species, redescription of G. hemigymnum, molecular phylogeny of the genus, and key to Atlantic species.

    PubMed

    Van Tassell, James L; Joyeux, Jean-Christophe; Macieira, Raphael Mariano; Tornabene, Luke

    2015-01-01

    It is unclear how many species of Gobiosoma occur in Brazil and what their geographic distributions are. Here we combine data from a comprehensive morphological survey and a molecular analysis to clarify this uncertain taxonomy and place Brazilian Gobiosoma within a phylogenetic framework. Recent collections in Brazil, from the states of Ceará to Santa Catarina, and in Uruguay yielded two allopatric species of Gobiosoma that are distinct in genetics, meristics, morphometrics, scale pattern and coloration. Comparisons were made with types and specimens of Gobiosoma hemigymnum, Garmannia mediocricula, Gobiosoma spilotum and Gobiosoma parri and all other known species of Gobiosoma. We place G. parri in synonomy with G. hemigymnum with a distribution of Rio de Janeiro to Uruguay and Argentina. The northern species, that extends from the states of Espírito Santo to Ceará, is described as a new species, Gobiosoma alfiei. A key to the Atlantic species of Gobiosoma is provided. PMID:26623827

  16. Fine structure of the Plasmodia and Myxospore of Ellipsomyxa gobioides n. sp. (Myxozoa) found in the gallbladder of Gobioides broussonnetii (Teleostei: Gobiidae) from the lower Amazon river.

    PubMed

    Azevedo, Carlos; Videira, Marcela; Casal, Graça; Matos, Patrícia; Oliveira, Elsa; Al-Quraishy, Saleh; Matos, Edilson

    2013-01-01

    A fish infecting myxosporean Ellipsomyxa gobioides n. sp. is described in the gallbladder of the Amazonian dragon fish Gobioides broussonnetii. Irregular disporous plasmodia (up to ~30 μm in diameter) with long branched and anastomosed pseudopodia were found attached to the gallbladder wall. Mature ellipsoid myxospores occurring floating in the bile measured 6.8 (6.5-7.0) μm (n = 30) long, 7.2 (6.9-7.5) μm (n = 15) wide, and 13.1 (12.8-13.5) (n = 25) thick. They had smooth thin valves elongated in the direction perpendicular to the plane of the straight central transverse sutural line. The two ellipsoidal polar capsules (PC) opened some distance from the sutural line on opposite sides, each measuring 4.6 (4.3-4.8) μm (n = 15) long and 2.5 (2.1-2.7) μm (n = 20) wide. Distance between PC 3.5 (3.1-3.8) μm (n = 15) in apical view. The polar filament was isofilar and consisted of a single coil with five or six turns. The objective of this study was to characterize this new species based on its morphological differences from the three previously described species. This is the first reported species of genus Ellipsomyxa from among the South American fauna. PMID:23869881

  17. Behaviour of the three-spined stickleback, Gasterosteous aculeatus (Gasterosteidae, Teleostei) in the multispecies freshwater biomonitor: a validation of automated recordings at three levels of ammonia pollution.

    PubMed

    Craig, Stephen; Laming, Peter

    2004-04-01

    The validity of using an automated online biomonitoring system, the multispecies freshwater biomonitor (MFB), in recording the physiological and behavioural activities of the three-spined stickleback Gasterosteous aculeatus, is assessed. The direct impact of the alternating electrical current generated by the impedance converter on fish activity was measured using a repeated measures design, machine on/machine off. Twelve subjects were used in each of three experimental groups: (1). standard hard water environment (control), (2). 0.1mM NH(4)Cl and (3). 10mM NH(4)Cl. Impedance generated waves were compared to corresponding manually recorded behavioural observations in an attempt to calibrate the MFB, assigning particular behaviours to a particular frequency and amplitude range. Data analysis suggests that the MFB current did not affect fish behaviour at any of the three contamination levels studied. Furthermore, analysis of the frequency with which behavioural activity changed (activity phases classified as inactive or active) showed that MFB behavioural data was not significantly different from that recorded manually. This suggested that the MFB recorded the behaviours that were concurrently observed. The feasibility of using the MFB as an effective behavioural early warning system in an aquacultural environment and as a scientific tool for toxicity testing is discussed. PMID:15087196

  18. †Kenyaichthyidae fam. nov. and †Kenyaichthys gen. nov. – First Record of a Fossil Aplocheiloid Killifish (Teleostei, Cyprinodontiformes)

    PubMed Central

    Altner, Melanie; Reichenbacher, Bettina

    2015-01-01

    The extant Cyprinodontiformes (killifishes) with their two suborders Cyprinodontoidei and Aplocheiloidei represent a diverse and well-studied group of fishes. However, their fossil record is comparatively sparse and has so far yielded members of the Cyprinodontoidei only. Here we report on cyprinodontiform fossils from the upper Miocene Lukeino Formation in the Tugen Hills of the Central Rift Valley of Kenya, which represent the first fossil record of an aplocheiloid killifish. A total of 169 specimens - mostly extraordinarily well preserved - and a sample of ten extant cyprinodontiform species were studied on the basis of morphometrics, meristics and osteology. A phylogenetic analysis using PAUP was also conducted for the fossils. Both the osteological data and the phylogenetic analysis provide strong evidence for the assignment of the fossils to the Aplocheiloidei, and justify the definition of the new family †Kenyaichthyidae, the new genus †Kenyaichthys and the new species †K. kipkechi sp. nov. The phylogenetic analysis unexpectedly places †Kenyaichthys gen. nov. in a sister relationship to the Rivulidae (a purely Neotropical group), a probable explanation might be lack of available synapomorphies for the Rivulidae, Nothobranchiidae and Aplocheilidae. The specimens of †K. kipkechi sp. nov. show several polymorphic characters and large overlap in meristic traits, which justifies their interpretation as a species flock in statu nascendi. Patterns of variation in neural and haemal spine dimensions in the caudal vertebrae of †Kenyaichthys gen. nov. and the extant species studied indicate that some previously suggested synapomorphies of the Cyprinodontoidei and Aplocheiloidei need to be revised. PMID:25923654

  19. Omanicotyle heterospina n. gen. et n. comb. (Monogenea: Microcotylidae) from the gills of Argyrops spinifer (Forsskål) (Teleostei: Sparidae) from the Sea of Oman

    PubMed Central

    2013-01-01

    Background The Sultanate of Oman’s aquaculture industry is expanding with an on-going assessment of potential new fish species for culture. The king soldier bream, Argyrops spinifer (Forsskål) (Sparidae), is one such species that is under consideration. During a routine health assessment of specimens caught in the Sea of Oman throughout the period November 2009 to March 2011, a number of gill polyopisthocotylean monogeneans were recovered. Methods A subsequent study of the monogeneans using a range of morphology-based approaches indicated that these were Bivagina heterospina Mamaev et Parukhin, 1974. In the absence of pre-existing molecular data, an expanded description of this species is provided, including a differential diagnosis with other species and genera belonging to the subfamily Microcotylinae Monticelli, 1892 with the subsequent movement of this species to a new genus to accommodate it. Results The polyopisthocotyleans collected from the gills of A. spinifer appear to be unique within the family Microcotylidae Taschenberg, 1879 in that, morphologically, they possess a pair of large, muscular vaginae each armed with a full crown of 16–18 robust spines and a unique dorsal region of folded tegument, which permits their discrimination from species of Bivagina Yamaguti, 1963. Sequencing of the SSU rDNA (complete 1968 bp) and LSU rDNA (partial 949 bp) places the specimens collected during this study within the subfamily Microcotylinae, but the LSU rDNA sequence differs from Bivagina and also from other microcotylid genera. Morphological features of B. heterospina sensu Mamaev et Parukhin, 1974 and the specimens collected from the current study are consistent with one another and represent a single species. The vaginal armature of these worms is unique and differs from all other genera within the Microcotylinae, including Bivagina, and its movement to Omanicotyle n. gen. to accommodate this species is proposed. Conclusions A new genus, Omanicotyle n. gen., is erected to accommodate Omanicotyle [Bivagina] heterospina n. comb. which represents the first monogenean to be described from Omani marine waters. Given the pathogenic potential of microcotylids on captive held fish stocks, a full assessment of Omanicotyle heterospina n. gen. et n. comb. is now required before large-scale production commences. PMID:23758894

  20. A phylogenetic analysis of pygmy perches (Teleostei: Percichthyidae) with an assessment of the major historical influences on aquatic biogeography in southern Australia.

    PubMed

    Unmack, Peter J; Hammer, Michael P; Adams, Mark; Dowling, Thomas E

    2011-12-01

    The biogeography of southern Australia is characterized by a repeated pattern of relatedness between the biota of southwestern and southeastern Australia. Both areas possess a temperate climate but are separated by a vast arid region, currently lacking permanent freshwater habitats, which has become increasingly drier since about 15 Ma. Aquatic organisms have thus potentially remained isolated for a considerable time. Pygmy perches (Nannatherina and Nannoperca, Percichthyidae) provide an excellent scenario for investigating biogeographic relationships between southwestern and southeastern regions as multiple species occur on either side of Australia. This allows us to potentially differentiate between "Multiple Invasion" and "Endemic Speciation," the two major hypotheses proposed to account for current distributions. The first suggests that multiple east-west movements have occurred, whereas the second suggests a single east-west split, with current biodiversity in each region being reciprocally monophyletic. Systematic relationships within this group were investigated with the mitochondrial cytochrome b gene; nuclear intron and exon sequences from S7, RAG1, and RAG2; and 53 allozyme loci. Our data supported the hypothesis of multiple movements across southern Australia based on a consistent lack of support for reciprocal monophyly of eastern and western species. This study appears to be the first example of an animal group displaying clear multiple east-west movement in southern Australia, as all other aquatic and terrestrial fauna previously examined displayed a single east-west split. Despite a high degree of sympatry within each region, the only evidence for hybridization was found between Nannoperca australis and N. obscura, with the latter having its mitochondrial genome completely replaced by that of N. australis, with no evidence for nuclear introgression. This is one of only a few confirmed examples of complete replacement of the mitochondrial genome in one species with that of another. Cryptic differentiation was also evident within the two most widespread species, N. australis and N. vittata, indicating that these likely consist of multiple species. We also highlight the need for multiple molecular markers with different strengths in order to obtain a more robust phylogeny, despite problems resulting from potential incongruences between data sets. PMID:21551126

  1. Cryptic speciation within the Neotropical cichlid Geophagus brasiliensis (Quoy & Gaimard, 1824) (Teleostei Cichlidae): a new paradigm in karyotypical and molecular evolution.

    PubMed

    Alves-Silva, Ana Paula; Dergam, Jorge Abdala

    2015-02-01

    The family Cichlidae is one of the most species-rich taxa in the Neotropics. However, the factors that determine these high levels of biodiversity remain unexplored. We have analyzed the morphological, cytogenetic, and molecular data from 62 specimens of a widespread cichlid, Geophagus brasiliensis, from three adjacent basins in southeastern Brazil. Morphological analyses did not show differences among specimens. The cytogenetic data indicate the occurrence of multiple nucleolar organizer regions and four sympatric karyotypes that differ in the first pair of chromosome morphology, in the Doce River Basin; whereas the karyotype from the Paraba do Sul Basin is widely divergent. The molecular data--616 bp fragment of cytochrome oxidase subunit I--revealed two haplogroups with the deepest genetic divergence (6.4%) ever reported within a nominal species in the Neotropical Region: One of the haplogroups is restricted to the quaternary lakes in the middle portion of the Doce Basin and the Mucuri River, whereas the other haplogroup is composed of haplotypes from elsewhere in the Doce Basin and the Paraba do Sul Basin. These patterns suggest that G. brasiliensis undergoes a cryptic speciation process involving three major lineages that differ from the African explosive cichlid radiation. PMID:25495140

  2. Genetic heterogeneity reveals on-going speciation and cryptic taxonomic diversity of stream-dwelling gudgeons (Teleostei, Cyprinidae) in the middle Danubian hydrosystem (Hungary).

    PubMed

    Takcs, Pter; Bihari, Pter; Er?s, Tibor; Speczir, Andrs; Szivk, Ildik; Br, Pter; Csoma, Eszter

    2014-01-01

    Although stream-dwelling gudgeons (Cyprinidae, genus: Gobio) are widespread in Central Europe, the taxonomy of this group and the distribution of its species are still unexplored in detail. The aims of our study are to ascertain taxonomic composition and distribution of the former Gobio gobio superspecies in the inner area of the Carpathian Basin. Since the presence of cryptic species is suspected in this area, we examined the taxonomic and phylogenetic relationships of Central European Gobio taxa by sequencing the mitochondrial DNA control region (mtCR). Additionally, we characterized the genetic structure of 27 stream-dwelling gudgeon populations of this area by Amplified Fragment Length Polymorphism (AFLP). Results of mtCR analysis proved the presence of three species already known as G. obtusirostris (dominant in NW-Hungary), G. gobio (sporadic) and G. carpathicus (sporadic). Additionally, the analysis revealed the existence of one doubtful taxon, G. sp1 (dominant in NE-Hungary), and a new isolated haplogroup (dominant in SW-Hungary). Although Network analysis showed significant detachment among haplogroups, their genetic distances were quite small. Therefore Bayesian phylogenetic analysis showed weak nodal support for the branching pattern both for newly described haplotypes, and for the already accepted species. AFLP data showed distinct population structure and a clear pattern of isolation was revealed by distance of stocks. At the same time, level of separation was not affected by the altitudinal position of sites. Moreover we found three major clusters of populations which were separated according to hydrographic regions, and corresponded to the findings of mtCR analysis. Our results suggest the on-going speciation of gudgeons in the Carpathian Basin, however the separation of haplogroups seems to only be an intermediate phase. The discovered natural pattern seems to be only slightly influenced by anthropogenic impacts. Additionally our results put into question the suitability of the recently accepted within Gobio genus taxonomy. PMID:24824751

  3. Genetic Heterogeneity Reveals On-Going Speciation and Cryptic Taxonomic Diversity of Stream-Dwelling Gudgeons (Teleostei, Cyprinidae) in the Middle Danubian Hydrosystem (Hungary)

    PubMed Central

    Takcs, Pter; Bihari, Pter; Er?s, Tibor; Speczir, Andrs; Szivk, Ildik; Br, Pter; Csoma, Eszter

    2014-01-01

    Although stream-dwelling gudgeons (Cyprinidae, genus: Gobio) are widespread in Central Europe, the taxonomy of this group and the distribution of its species are still unexplored in detail. The aims of our study are to ascertain taxonomic composition and distribution of the former Gobio gobio superspecies in the inner area of the Carpathian Basin. Since the presence of cryptic species is suspected in this area, we examined the taxonomic and phylogenetic relationships of Central European Gobio taxa by sequencing the mitochondrial DNA control region (mtCR). Additionally, we characterized the genetic structure of 27 stream-dwelling gudgeon populations of this area by Amplified Fragment Length Polymorphism (AFLP). Results of mtCR analysis proved the presence of three species already known as G. obtusirostris (dominant in NW-Hungary), G. gobio (sporadic) and G. carpathicus (sporadic). Additionally, the analysis revealed the existence of one doubtful taxon, G. sp1 (dominant in NE-Hungary), and a new isolated haplogroup (dominant in SW-Hungary). Although Network analysis showed significant detachment among haplogroups, their genetic distances were quite small. Therefore Bayesian phylogenetic analysis showed weak nodal support for the branching pattern both for newly described haplotypes, and for the already accepted species. AFLP data showed distinct population structure and a clear pattern of isolation was revealed by distance of stocks. At the same time, level of separation was not affected by the altitudinal position of sites. Moreover we found three major clusters of populations which were separated according to hydrographic regions, and corresponded to the findings of mtCR analysis. Our results suggest the on-going speciation of gudgeons in the Carpathian Basin, however the separation of haplogroups seems to only be an intermediate phase. The discovered natural pattern seems to be only slightly influenced by anthropogenic impacts. Additionally our results put into question the suitability of the recently accepted within Gobio genus taxonomy. PMID:24824751

  4. Variation in thermal tolerance and routine metabolism among spring- and stream-dwelling freshwater sculpins (Teleostei: Cottidae) of the southeastern United States

    USGS Publications Warehouse

    Walsh, S.J.; Haney, D.C.; Timmerman, C.M.

    1997-01-01

    Evolutionary theory predicts that some aquatic organisms may adapt by directional selection to limiting physical environmental conditions, yet empirical data are conflicting. We sought to test the assumption that sculpins (family Cottidae) inhabiting thermally stable springs of the southeastern United States differ in temperature tolerance and metabolism from populations inhabiting more thermally labile stream habitats. Spring populations of pygmy sculpins (Coitus pygmaeus) and Ozark sculpins (C. hypselurus) differed interspecifically in thermal tolerance from populations of stream-dwelling mottled (C. bairdi) and Tallapoosa sculpins (C. tallapoosae), and both stream and spring populations of banded sculpins (C. carolinae). No intra- or interspecific differences in thermal tolerance were found among populations of C. bairdi, C. tallapoosae, or C. carolinae. Coitus pygmaeus acclimated to 15??C differed intraspecifically in routine metabolism from fish acclimated to 20?? and 25??C. Cottus pygmaeus and stream-dwelling C. bairdi and C. carolinae acclimated to temperatures of 20?? and 25??C showed no interspecific differences in routine metabolism. Our results suggest that some spring-adapted populations or species may be more stenothermal than stream-dwelling congeners, but a greater understanding of the interactions of other physical and biological factors is required to better explain micro- and macrohabitat distributions of eastern North American sculpins.

  5. Delimiting the Origin of a B Chromosome by FISH Mapping, Chromosome Painting and DNA Sequence Analysis in Astyanax paranae (Teleostei, Characiformes)

    PubMed Central

    Silva, Duílio M. Z. de A.; Pansonato-Alves, José Carlos; Utsunomia, Ricardo; Araya-Jaime, Cristian; Ruiz-Ruano, Francisco J.; Daniel, Sandro Natal; Hashimoto, Diogo Teruo; Oliveira, Cláudio; Camacho, Juan Pedro M.; Porto-Foresti, Fábio; Foresti, Fausto

    2014-01-01

    Supernumerary (B) chromosomes have been shown to contain a wide variety of repetitive sequences. For this reason, fluorescent in situ hybridisation (FISH) is a useful tool for ascertaining the origin of these genomic elements, especially when combined with painting from microdissected B chromosomes. In order to investigate the origin of B chromosomes in the fish species Astyanax paranae, these two approaches were used along with PCR amplification of specific DNA sequences obtained from the B chromosomes and its comparison with those residing in the A chromosomes. Remarkably, chromosome painting with the one-arm metacentric B chromosome probe showed hybridization signals on entire B chromosome, while FISH mapping revealed the presence of H1 histone and 18S rDNA genes symmetrically placed in both arms of the B chromosome. These results support the hypothesis that the B chromosome of A. paranae is an isochromosome. Additionally, the chromosome pairs Nos. 2 or 23 are considered the possible B chromosome ancestors since both contain syntenic H1 and 18S rRNA sequences. The analysis of DNA sequence fragments of the histone and rRNA genes obtained from the microdissected B chromosomes showed high similarity with those obtained from 0B individuals, which supports the intraspecific origin of B chromosomes in A. paranae. Finally, the population hereby analysed showed a female-biased B chromosome presence suggesting that B chromosomes in this species could influence sex determinism. PMID:24736529

  6. Multilocus analyses of an Antarctic fish species flock (Teleostei, Notothenioidei, Trematominae): phylogenetic approach and test of the early-radiation event.

    PubMed

    Janko, Karel; Marshall, Craig; Musilov, Zuzana; Van Houdt, Jeroen; Couloux, Arnaud; Cruaud, Corinne; Lecointre, Guillaume

    2011-09-01

    Clades that have undergone episodes of rapid cladogenesis are challenging from a phylogenetic point of view. They are generally characterised by short or missing internal branches in phylogenetic trees and by conflicting topologies among individual gene trees. This may be the case of the subfamily Trematominae, a group of marine teleosts of coastal Antarctic waters, which is considered to have passed through a period of rapid diversification. Despite much phylogenetic attention, the relationships among Trematominae species remain unclear. In contrast to previous studies that were mostly based on concatenated datasets of mitochondrial and/or single nuclear loci, we applied various single-locus and multilocus phylogenetic approaches to sequences from 11 loci (eight nuclear) and we also used several methods to assess the hypothesis of a radiation event in Trematominae evolution. Diversification rate analyses support the hypothesis of a period of rapid diversification during Trematominae history and only a few nodes in the hypothetical species tree were consistently resolved with various phylogenetic methods. We detected significant discrepancies among trees from individual genes of these species, most probably resulting from incomplete lineage sorting, suggesting that concatenation of loci is not the most appropriate way to investigate Trematominae species interrelationships. These data also provide information about the possible effects of historic climate changes on the diversification rate of this group of fish. PMID:21402163

  7. Four species of Stephanostomum Looss, 1899 (Digenea: Acanthocolpidae) from Seriola dumerili (Risso) (Teleostei: Carangidae) in the western Mediterranean, including S. euzeti n. sp.

    PubMed

    Bartoli, Pierre; Bray, Rodney A

    2004-05-01

    Four species of Stephanostomum are described from various sites in Seriola dumerili from off Corsica, France. S. ditrematis (Yamaguti, 1939), from the stomach, pyloric caeca and duodenum, has 36 circum-oral spines. S. seriolae Yamaguti, 1970 is considered a synonym of S. ditrematis. S. filiforme Linton, 1940, from the mid-intestine, has 43-46 circum-oral spines. S. petimba Yamaguti, 1970, from the rectum, has a 42 circum-oral spines. S. euzeti n. sp. has 49-51 circum-oral spines, and differs from worms with a similar anterior extent of the vitellarium and circum-oral spine number in details of the vitelline distribution and the distances between the gonads. Attention is drawn to the presence in the rectum of S. dumerili of sympatric species differentiated mainly on circum-oral spine number. PMID:15084832

  8. Evaluation of pre- and post-zygotic mating barriers, hybrid fitness and phylogenetic relationship between Cyprinodon variegatus variegatus and Cyprinodon variegatus hubbsi (Cyprinodontiformes, Teleostei).

    PubMed

    Brix, K V; Grosell, M

    2013-04-01

    The euryhaline fish Cyprinodon variegatus variegatus (Cvv) is capable of tolerating ambient salinities ranging from 0.3 to 167 g l(-1) , but incapable of long-term survival in freshwater (< 2 mM Na(+) ). However, a population of this species, now designated as a subspecies (Cyprinodon variegatus hubbsi; Cvh), has been isolated in several freshwater (0.4-1 mM Na(+) ) lakes in central Florida for the past ~150 ky. We previously demonstrated that Cvh has a significantly higher affinity for Na(+) uptake suggesting that it has adapted to its dilute freshwater environment. We here evaluate whether Cvh should be considered a separate species by characterizing pre- and post-zygotic isolation, Na(+) transport characteristics of the two populations and their hybrids, and developing a molecular phylogeny of Cvv and Cvh populations in Florida using mtDNA sequence data. We found evidence of partial prezygotic isolation with Cvv females mating almost exclusively (89%) with con-specific males in choice mating experiments. Partial post-zygotic isolation was also observed with significant (59-89%) reductions in hatching success of hybrid embryos compared with con-specific embryos. Na(+) uptake kinetics in hybrids (both Cvv x Cvh and Cvh x Cvv) bred and raised under common garden conditions were intermediate to Cvh (high affinity) and Cvv (low affinity) indicating that observed differences are genetically based. Similar observations were made with respect to short-term (96 h) survival of juveniles acutely transferred from 7 mM Na(+) to a range of more dilute (0.1-2 mM Na(+) ) freshwater. Finally, although phylogenetic analysis of Cvv and Cvh populations using mtDNA sequence for ND2 were unable to fully resolve a polytomy between Cvh and Cvv populations from northeastern Florida, these data do not falsify the hypothesis that Cvh is of monophyletic origin. Overall, the available data suggest that Cvh should be considered a separate species or at a minimum an evolutionarily significant unit. PMID:23480788

  9. Pethia aurea (Teleostei: Cyprinidae), a new species of barb from West Bengal, India, with redescription of P. gelius and P. canius.

    PubMed

    Knight, J D Marcus

    2013-01-01

    Fishes currently assigned to Pethia gelius Hamilton from West Bengal are shown to belong to a closely-related group of three species: P gelius, its erstwhile synonym P canius Hamilton and a new species, P aurea. The three species are distinguished from all other species of Pethia by having the lateral line incomplete, with 3-4 pored scales; 20-26 scales in lateral series on body; 4-5/l/2-3 scales in transverse line on body; 8-9 predorsal scales; barbels absent and by a unique colour pattern consisting of two or three black blotches on the body (which, however, fade on preservation), the first behind the opercle, the second beneath the origin of the dorsal fin, extending to the mid-lateral region, and the third above the origin of the anal fin. A black spot is also present at the base of the dorsal and anal fins. Additionally, P gelius is distinguished by having the last unbranched dorsal-fin ray thick, straight, serrated, with 20-25 serrae on its posterior margin; a snout length of 6.1-8.4% standard length (SL); a body depth of 32.6-37.7% SL; and a dorsal-fin height of 19.4-22.8% SL. Pethia canius is additionally distinguished by having a snout length of 8.9-11.8% SL; a body depth of 28.1-32.2% SL; and dorsal-fin height of 26.9-32.8% SL. Pethia aurea, new species, is additionally distinguished from all its congeners by having 5/1/3-3 scales in transverse line on body; 9 pre-dorsal scales; and last unbranched dorsal-fin ray slender, serrated, with 19-22 serrae on posterior margin. PMID:26106720

  10. Molecular cytogenetic analysis of the crucian carp, Carassius carassius (Linnaeus, 1758) (Teleostei, Cyprinidae), using chromosome staining and fluorescence in situ hybridisation with rDNA probes

    PubMed Central

    Spoz, Aneta; Boron, Alicja; Porycka, Katarzyna; Karolewska, Monika; Ito, Daisuke; Abe, Syuiti; Kirtiklis, Lech; Juchno, Dorota

    2014-01-01

    Abstract The crucian carp Carassius carassius (Linnaeus, 1758) is a species with restricted and decreasing distribution in Europe. Six males and six females of the species from the Baltic Sea basin in Poland were examined to show sequentially CMA3/AgNO3 staining pattern, DAPI staining, and, for the first time in literature, molecular cytogenetic analysis using double-colour fluorescence in situ hybridisation (FISH) with 28S and 5S rDNA probes. The karyotype consisted of 20 m, 36 sm and 44 sta chromosomes, NF=156. The AgNO3 stained NORs were most frequently located terminally in the short arms of two sm and two sta elements, and CMA3-positive sites were also observed suggesting abundant GC-rich repetitive DNA in the regions. Other CMA3-positive sites in the short arms of six to ten sm and sta chromosomes were detected. The results based on 28S rDNA FISH confirmed the location of rDNA sites. DAPI-negative staining of NORs suggested the scarcity of AT-rich DNA in the regions. FISH with 5S rDNA probe revealed 8–14 loci (ten and 12 in respectively 49 and 29% of metaphases). They were located in two sm and eight to ten sta chromosomes and six of them were larger than others. Simultaneously, mapping of the two rDNA families on the chromosomes of C. carassius revealed that both 28S and 5S rDNA probes were located in different chromosomes. Molecular cytogenetic data of C. carassius presented here for the first time give an important insight into the structure of chromosomes of this polyploid and declining species and may be useful in its systematics. PMID:25349674

  11. De novo assembly and characterization of the skeletal muscle and electric organ transcriptomes of the African weakly electric fish Campylomormyrus compressirostris (Mormyridae, Teleostei).

    PubMed

    Lamanna, Francesco; Kirschbaum, Frank; Tiedemann, Ralph

    2014-11-01

    African weakly electric fishes (Mormyridae) underwent an outstanding adaptive radiation (about 200 species), putatively owing to their ability to communicate through species-specific weak electric signals. The electric organ discharge (EOD) is produced by muscle-derived electrocytes organized in piles to form an electric organ. Despite the importance of this trait as a prezygotic isolation mechanism, genomic resources remained limited. We present here a first draft of the skeletal muscle and electric organ transcriptomes from the weakly electric fish species Campylomormyrus compressirostris, obtained using the Illumina HiSeq2000 sequencing technology. Approximately 6.8 Gbp of cDNA sequence data were produced from both tissues, resulting in 57,268,109 raw reads for the skeletal muscle and 46,934,923 for the electric organ, and assembled de novo into 46,143 and 89,270 contigs, respectively. About 50% of both transcriptomes were annotated after protein databases search. The two transcriptomes show similar profiles in terms of Gene Ontology categories composition. We identified several candidate genes which are likely to play a central role in the production and evolution of the electric signal. For most of these genes, and for many other housekeeping genes, we were able to obtain the complete or partial coding DNA sequences (CDS), which can be used for the development of primers to be utilized in qRT-PCR experiments. We present also the complete mitochondrial genome and compare it to those available from other weakly electric fish species. Additionally, we located 1671 SSR-containing regions with their flanking sites and designed the relative primers. This study establishes a first step in the development of genomic tools aimed at understanding the role of electric communication during speciation. PMID:24690394

  12. [Hyphessobrycon taphorni and H. eschwartzae (Teleostei: Characidae) two new species of fish in the basin of Madre de Dios river, Peru].

    PubMed

    Garcia-Alzate, Carlos A; Romin-Valencia, Csar; Ortega, Hernn

    2013-06-01

    Hyphessobrycon with 129 valid species, is a genus of fish that has a great diversity of species in the Neotropical ichthyofauna, reaches its greatest diversity in the Amazon basin with about 70% of these species, is highly desired by hobbyists because of their beauty and color, and are still meeting new species. We analyzed specimens from the Departamento de Ictiologa, Museo de Historia Natural de la Universidad Mayor de San Marcos, Lima, Per (MUSM); and measurements of the specimens were taken point to point with digital calipers. Observations of bone and cartilage structures were made on cleared and stained (C&S) samples. The morphometric relationships between species using 21 variables were explored using a principal component analysis (PCA). Here we describe two new species, Hyphessobrycon taphorni and H. eschwartzae from the Madre de Dios River drainage, Peru. Hyphessobrycon taphorni sp. n. can be distinguished by the number of dorsal-fin rays (iii, 8), by the number of: pored lateral-line scales (4-5), teeth in the outer premaxillary row (1-2), teeth in the inner premaxillary row (7-8), by: the caudal-peduncle length (11.4-16.4% SL), number of lateral scales (28-29, except from H. loretoensis which has 29-30) and absence of a humeral spot (vs. present), it differs from H. loretoensis by the number of: scales between the lateral line and the anal fin origin (4 vs. 3) and maxillary teeth (2 vs. 3-4), and it differs from H. agulha by the number of branched pectoral-fin rays (11-12 vs. 9-10). Hyphessobrycon eschwartzae sp. n. is distinguished by the number of: simple anal-fin rays (iv), teeth on the dentary (13-15), teeth in the inner premaxillary row (6), teeth in the outer premaxillary row (3, except from H. heterorhabdus and H. loretoensis which have 3-4); it differs from H. loretoensis by the number of: pored lateral-line scales (7 vs. 9-10), scales between the lateral line and the dorsal-fin origin (5 vs. 3-4); it differs from H. agulha in the number of lateral scales (30-31 vs. 33-34), by the number of: predorsal scales (9 vs. 10), maxillary teeth (4 vs. 0-1); in having in life a red lateral stripe above the dark lateral stripe that extends from the posterior part of the opercle to the caudal peduncle (vs. absent) and by the presence of bony hooks in mature males only on the anal fin (vs. hooks on all fins, including the caudal). PMID:23885596

  13. Phylogenetic analysis of molecular and morphological data highlights uncertainty in the relationships of fossil and living species of Elopomorpha (Actinopterygii: Teleostei).

    PubMed

    Dornburg, Alex; Friedman, Matt; Near, Thomas J

    2015-08-01

    Elopomorpha is one of the three main clades of living teleost fishes and includes a range of disparate lineages including eels, tarpons, bonefishes, and halosaurs. Elopomorphs were among the first groups of fishes investigated using Hennigian phylogenetic methods and continue to be the object of intense phylogenetic scrutiny due to their economic significance, diversity, and crucial evolutionary status as the sister group of all other teleosts. While portions of the phylogenetic backbone for Elopomorpha are consistent between studies, the relationships among Albula, Pterothrissus, Notacanthiformes, and Anguilliformes remain contentious and difficult to evaluate. This lack of phylogenetic resolution is problematic as fossil lineages are often described and placed taxonomically based on an assumed sister group relationship between Albula and Pterothrissus. In addition, phylogenetic studies using morphological data that sample elopomorph fossil lineages often do not include notacanthiform or anguilliform lineages, potentially introducing a bias toward interpreting fossils as members of the common stem of Pterothrissus and Albula. Here we provide a phylogenetic analysis of DNA sequences sampled from multiple nuclear genes that include representative taxa from Albula, Pterothrissus, Notacanthiformes and Anguilliformes. We integrate our molecular dataset with a morphological character matrix that spans both living and fossil elopomorph lineages. Our results reveal substantial uncertainty in the placement of Pterothrissus as well as all sampled fossil lineages, questioning the stability of the taxonomy of fossil Elopomorpha. However, despite topological uncertainty, our integration of fossil lineages into a Bayesian time calibrated framework provides divergence time estimates for the clade that are consistent with previously published age estimates based on the elopomorph fossil record and molecular estimates resulting from traditional node-dating methods. PMID:25899306

  14. Comparative evaluation of Na(+) uptake in Cyprinodon variegatus variegatus (Lacepede) and Cyprinodon variegatus hubbsi (Carr) (Cyprinodontiformes, Teleostei): Evaluation of NHE function in high and low Na(+) freshwater.

    PubMed

    Brix, Kevin V; Esbaugh, Andrew J; Mager, Edward M; Grosell, Martin

    2015-07-01

    The euryhaline pupfish, Cyprinodon variegatus variegatus (Cvv), can successfully osmoregulate in ?2 mM Na(+) and a freshwater population (Cyprinodon variegatus hubbsi; Cvh) osmoregulates at ?0.1mM Na(+). We previously demonstrated that Cvv relies on an apical NKCC and NHE in the gill for Na(+) uptake in high (7mM) and intermediate (2 mM) Na(+) concentrations, while Cvh relies only on NHE for Na(+) uptake. This study investigated whether differential NHE isoform use explains differences in Na(+) uptake kinetics between these two populations. We further studied whether Cvh uses a NHE-Rh metabolon or carbonic anhydrase (CA) to overcome thermodynamic challenges of NHE function in dilute freshwater. Transfer to more dilute freshwater resulted in upregulation of nhe-2 (Cvv only) and nhe-3 (Cvv and Cvh). Relative expression of nhe-3 compared to nhe-2 was 2-fold higher in Cvv, but 200-fold higher in Cvh suggesting that nhe-3 expression is an important freshwater adaptation for Cvh. Simultaneous measurement of Na(+) and Tamm flux under various conditions provided no support for a NHE-Rh metabolon in either population. Carbonic anhydrase activity in Cvv was comparable in 7 and 2 mM Na(+) acclimated fish. In Cvh, CA activity increased by 75% in 0.1 mM Na(+) acclimated fish compared to 7 mM Na(+) fish. Ethoxzolamide had variable effects, stimulating and reducing Na(+) uptake in Cvv acclimated to 7 and 2 mM Na(+), while reducing Na(+) uptake in 7 and 0.1mM Na(+) acclimated Cvh. This suggests that CA plays important, but different roles in regulating Na(+) uptake in Cvv and Cvh. PMID:25868437

  15. Micronucleus test in erythrocytes of Barbus plebejus (Teleostei, Pisces) from two natural environments: a bioassay for the in situ detection of mutagens in freshwater.

    PubMed

    Minissi, S; Ciccotti, E; Rizzoni, M

    1996-04-01

    Erythrocyte micronucleus frequencies in wild fish from two riverine environments and in fish reproduced and reared under controlled conditions (control group) were compared, with the aim to evaluate the suitability of the MN test for the in situ detection of mutagens in freshwaters. Fish were caught in different months in two rivers of central Italy which have different pollution levels. As indicator species, the barbel (Barbus plebejus) was chosen because of its ecological significance. Blood samplings were performed on wild fish immediately after capture and repeated at different time intervals on the same individuals, which were maintained in controlled conditions after capture. A total of 10,000 erythrocytes per specimen were scored. No significant differences in micronucleus frequencies were observed between the control group and fish from the unpolluted river (Mignone). A significantly higher frequency of micronuclei was observed in fish caught in the polluted river (Tiber), in comparison to both the controls and the Mignone river fish. No significant seasonal differences were observed. Barbels examined 50 and 100 days after capture presented a remarkable decrease in micronucleus frequency in comparison with the frequency observed in barbels at capture. The micronucleus test in fish erythrocytes was shown to be a sensitive bioassay for detecting mutagenic pollution in fresh water environments. PMID:8628332

  16. Karyotypic diversity in four species of the genus Gymnotus Linnaeus, 1758 (Teleostei, Gymnotiformes, Gymnotidae): physical mapping of ribosomal genes and telomeric sequences

    PubMed Central

    Scacchetti, Priscilla Cardim; Pansonato-Alves, Jos Carlos; Utsunomia, Ricardo; Oliveira, Claudio; Foresti, Fausto

    2011-01-01

    Abstract Conventional (Giemsa, C-Banding, Ag-NORs, CMA3) and molecular (5S rDNA, 18S rDNA, telomeric sequences) cytogenetic studies were carried out in specimens of ten distinct fish populations of the genus Gymnotus (Gymnotus sylvius Albert and Fernandes-Matioli, 1999, Gymnotus inaequilabiatus Valenciennes, 1839, Gymnotus pantherinus Steindachner, 1908, and G. cf. carapo Linnaeus, 1758) from different Brazilian hydrographic basins. Gymnotus sylvius presented a diploid number of 40 chromosomes (22m+12sm+6st), Gymnotus pantherinus presented 52 chromosomes (32m+18sm+2st), while Gymnotus inaequilabiatus (42m+10sm+2a)and Gymnotus cf. carapo (38m+12sm+4st) presented 54 chromosomes. The C-banding technique revealed centromeric marks in all chromosomes of all species. Besides that, conspicuous blocks of heterochromatin were found interstitially on the chromosomes of Gymnotus inaequilabiatus, Gymnotus cf. carapo,and Gymnotus pantherinus. All four species showed single nucleolus organizing regions confirmed by results obtained through Ag-NORs and FISH experiments using 18S rDNA probes, which showed the NORs localized on the first chromosome pair in Gymnotus inaequilabiatus, Gymnotus cf. carapo,and Gymnotus pantherinus, and on pair 2 in Gymnotus sylvius. CMA3 staining revealed additional unrelated NORs marks in Gymnotus sylvius and Gymnotus pantherinus. The 5S rDNA probes revealed signals on one pair in Gymnotus sylvius and two pairs in Gymnotus pantherinus; Gymnotus inaequilabiatus had about seventeen pairs marked, and Gymnotus cf. carapo had about fifteen pairs marked. It is considered that the high amount of heterochromatin identified in the chromosomes of Gymnotus inaequilabiatus and Gymnotus cf. carapo could have facilitated the dispersion of 5S rDNA in these species. Interstitial signals were detected on the first metacentric pair of Gymnotus sylvius by telomeric probes (TTAGGG)n indicating the possible occurrence of chromosomal fusions in this species. The present study reveals valuable cytotaxonomic markers for this group and allows a more precise evaluation of the processes involved in the karyotype differentiation and the interrelationships among different species of the genus Gymnotus. PMID:24260631

  17. Local ecological knowledge of the artisanal fishers on Epinephelus itajara (Lichtenstein, 1822) (Teleostei: Epinephelidae) on Ilhéus coast – Bahia State, Brazil

    PubMed Central

    2014-01-01

    Background Local Ecological Knowledge (LEK) of traditional fishermen may be the only source of information regarding the conservation of the marine ecosystem and its endangered species. One of these species is Epinephelus itajara, which can exceed 2 m in length and 400 kg weight, is classified by the IUCN as a critically endangered. In Brazil, there is currently a moratorium that prohibits the capture of this specie, and in the northeastern coast, a Marine Protected Area was recently established properly justified by the existence a one spawning aggregation. The scope of the present study was the analysis the LEK of fishers with the goal of contributing to the conservation of E. Itajara. Methods The Knowledge of 24 “experts” was recorded through semi-structured interviews with fishermen selected based on their expertise. LEK regarding some aspects of the life history of E. itajara, such as its morphology, spatial distribution, feeding, breeding and conservation, was systematized. The interviews were conducted in synchronic and diachronic situations. The data analysis followed the model of unity of the various individual skills, while the consistency of the analysis was tested using a matrix of methods employed in comparative cognitive science. Potential reproductive aggregation sites were identified by experts through projective interviews conducted based on a cartographic database and transferred to a geographic information system (GIS). Results The LEK of these specialists in relation to the biological and ecological characteristics of E. itajara showed a high level of detail and a high agreement with the scientific literature. Projective interviews are presented as a promising tool allowing spatialization of the information generated through the registration of LEK. Therefore, the visualization of information from the fishermen, as well as its analysis and comparison with other databases, is simplified, thereby contributing to the decision-making process concerning the conservation of marine ecosystem in Brazil. Conclusions Integration of LEK with scientific knowledge is an efficient strategy for the conservation of endangered species, as it provides important additional biological information that can be used in the process of participative and sustainable management of marine resources. PMID:24965849

  18. Combining geometric morphometrics with molecular genetics to investigate a putative hybrid complex: a case study with barbels Barbus spp. (Teleostei: Cyprinidae).

    PubMed

    Geiger, M F; Schreiner, C; Delmastro, G B; Herder, F

    2016-03-01

    This integrative study examined the morphological and genetic affinities of three endemic barbel species from Italy (brook barbel Barbus caninus, Italian barbel Barbus plebejus and horse barbel Barbus tyberinus) and of putative hybrid specimens to their species of origin. Two of the species frequently occur together with the non-native barbel Barbus barbus. DNA barcoding indicates that mitochondrial (mt) haplotypes often do not match the species expected from morphology. Linear distance measurements and meristics are not informative for discrimination of the species and putative hybrids, but a discriminant analysis of principal components (DAPC) of geometric landmark data produces reassignments largely in congruence with mt and nuclear genetic data. Cyto-nuclear conflicts confirm the presence of hybridization in B. plebejus and B. tyberinus and identify additional introgressed specimens. A comparison between mixed genotypes and their morphology-based assignment reveals no predictable pattern. The finding that most individuals of the morphologically similar B. plebejus and B. tyberinus have very high assignment probabilities to their respective species suggests that the presented approach may serve as a valuable tool to distinguish morphologically very similar taxa. PMID:26805755

  19. An experimental study on neural crest migration in Barbus conchonius (Cyprinidae, Teleostei), with special reference to the origin of the enteroendocrine cells.

    PubMed

    Lamers, C H; Rombout, J W; Timmermans, L P

    1981-04-01

    A neural crest transplantation technique is described for fish. As in other classes of vertebrates, two pathways of neural crest migration can be distinguished: a lateroventral pathway between somites and ectoderm, and a medioventral pathway between somites and neural tube/notochord. In this paper evidence is presented for a neural crest origin of spinal ganglion cells and pigment cells, and indication for such an origin is obtained for sympathetic and enteric ganglion cells and for cells that are probably homologues to adrenomedullary and paraganglion cells in the future kidney area. The destiny of neural crest cells near the developing lateral-line sense organs is discussed. When grafted into the yolk, neural crest cells or neural tube cells appear to differentiate into 'periblast cells'; this suggests a highly activating influence of the yolk. Many neural crest cells are found around the urinary ducts and, when grafted below the notochord, even within the urinary duct epithelium. These neural crest cells do not invade the gut epithelium, even when grafted adjacent to the developing gut. Consequently enteroendocrine cells in fish are not likely to have a trunk- or rhombencephalic neural crest origin. Another possible origin of these cells will be proposed. PMID:7276815

  20. Salinity tolerance of non-native Asian swamp eels (Teleostei: Synbranchidae) in Florida, USA: Comparison of three populations and implications for dispersal

    USGS Publications Warehouse

    Schofield, P.J.; Nico, L.G.

    2009-01-01

    Three populations of non-native Asian swamp eels are established in peninsular Florida (USA), and comprise two different genetic lineages. To assess potential for these fish to penetrate estuarine habitats or use coastal waters as dispersal routes, we determined their salinity tolerances. Swamp eels from the three Florida populations were tested by gradual (chronic) salinity increases; additionally, individuals from the Miami population were tested by abrupt (acute) salinity increases. Results showed significant tolerance by all populations to mesohaline waters: Mean survival time at 14 ppt was 63 days. The Homestead population, a genetically distinct lineage, exhibited greater tolerance to higher salinity than Tampa and Miami populations. Acute experiments indicated that swamp eels were capable of tolerating abrupt shifts from 0 to 16 ppt, with little mortality over 10 days. The broad salinity tolerance demonstrated by these experiments provides evidence that swamp eels are physiologically capable of infiltrating estuarine environments and using coastal waters to invade new freshwater systems. ?? 2009 US Government.