Sample records for acanthurus wiegmann decapoda

  1. Survey of protozoan, helminth and viral infections in shrimp Litopenaeus setiferus and prawn Macrobrachium acanthurus native to the Jamapa River region, Mexico.

    PubMed

    Domínguez-Machín, Magda E; Hernández-Vergara, Martha P; Jiménez-García, Isabel; Simá-Alvarez, Raúl; Rodríguez-Canul, Rossanna

    2011-09-09

    We surveyed protozoan and metazoan parasites as well as white spot syndrome virus (WSSV) and infectious hypodermal hematopoietic necrosis virus (IHHNV) in white shrimp Litopenaeus setiferus and the palaemonid prawn Macrobrachium acanthurus native to the lower Jamapa River region of Veracruz, Mexico. The presence of parasites and the infection parameters were evaluated in 113 palaemonid prawns collected during the northwind (n = 45), rainy (n = 38) and dry seasons (n = 30) between October 2007 and July 2008, and in 91 shrimp collected in the rainy season between May and June 2008. In L. setiferus, ciliates of the subclass Apostomatia (Ascophrys sp.) were evident in gills, and third-stage larvae of the nematode Physocephalus sexalatus were evident in the stomach. Cestodes of the genus Prochristianella were evident in the hepatopancreas, while some gregarines of the genus Nematopsis, as well as unidentified larval cestodes, were observed in the intestine. Histology identified Ascophrys sp. in association with gill necrosis and tissue melanization. Slight inflammation was observed in intestinal epithelium near cestode larvae. In M. acanthurus, epibionts of the protozoans Epistylis sp., Acineta sp. and Lagenophrys sp. were observed under uropods, periopods and pleopods. An unidentified ciliate of the Apostomatia was also found in the gills, and Nematopsis was identified in the intestine. No histopathology was observed in association with these parasites. Moreover, neither WSSV nor IHHNV were detected by the polymerase chain reaction (PCR) in any of the L. setiferus or M. acanthurus analysed.

  2. Pathological Study of Blood Parasites in Rice Field Frogs, Hoplobatrachus rugulosus (Wiegmann, 1834)

    PubMed Central

    Sailasuta, Achariya; Satetasit, Jetjun; Chutmongkonkul, Malinee

    2011-01-01

    One hundred and forty adult rice field frogs, Hoplobatrachus rugulosus (Wiegmann, 1834), were collected in Srakaew province, Thailand. For blood parasite examination, thin blood smears were made and routinely stained with Giemsa. The results showed that 70% of the frogs (98/140) were infected with 5 species of blood parasites, including a Trypanosoma rotatorium-like organism, Trypanosoma chattoni, Hepatozoon sp. a, Hepatozoon sp. b, and Lankesterella minima. Pathological examination of the liver, lung, spleen, and kidney of the frogs that were apparently infected with one of these blood parasites were collected and processed by routine histology and subsequently stained with haematoxylin and eosin. Histopathological findings associated with the Trypanosoma rotatorium-like organism and Trypanosoma chattoni-infected frogs showed no pathological lesions. Hepatozoon sp. a and Hepatozoon sp. b-infected frogs developed inflammatory lesions predominantly in the liver, demonstrating granuloma-like lesions with Hepatozoon sp. meronts at the centre. Tissue sections of Lankesterella minima-infected frogs also showed lesions. Liver and spleen showed inflammatory lesions with an accumulation of melanomacrophage centres (MMCs) surrounding the meronts and merozoites. It is suggested that Hepatozoon sp. a, Hepatozoon sp. b, and Lankesterella minima-infections are capable of producing inflammatory lesions in the visceral organs of rice field frogs, and the severity of lesions is tentatively related to levels of parasitemia. PMID:21918731

  3. A preliminary assessment of the deep-sea Decapoda collected during the KARUBENTHOS 2015 Expedition to Guadeloupe Island.

    PubMed

    Poupin, Joseph; Corbari, Laure

    2016-11-13

    A preliminary assessment of the deep-sea Decapoda is proposed for Guadeloupe Island based solely on high definition macro photographs taken during the KARUBENTHOS 2015 Expedition to the Island (R/V Antea, 7-29 June 2015). Overall, 190 species are recognized, several of which are depicted with their fresh color for the first time. Previous records in the Lesser Antilles are documented and the geographic distribution of the species in these Islands is given. The historical contribution of the steamer Blake (1878-1879) in the Lesser Antilles is emphasized. All species inventoried during KARUBENTHOS 2015 were already reported in the western Atlantic but 34 of them are new records for the Lesser Antilles and 116 are reported for the first time from Guadeloupe Island. This preliminary inventory is estimated to include about 38% of the deep-sea Decapoda potentially occurring around Guadeloupe Island.

  4. Clarifying functional roles: algal removal by the surgeonfishes Ctenochaetus striatus and Acanthurus nigrofuscus

    NASA Astrophysics Data System (ADS)

    Tebbett, Sterling B.; Goatley, Christopher H. R.; Bellwood, David R.

    2017-09-01

    The lined bristletooth, Ctenochaetus striatus, and the brown surgeonfish, Acanthurus nigrofuscus, are among the most abundant surgeonfishes on Indo-Pacific coral reefs. Yet, the functional role of these species has been the focus of an ongoing debate lasting at least six decades. Specifically, to what extent are C. striatus herbivorous like the visually similar A. nigrofuscus? To address this question, we used natural feeding surfaces, covered with late successional stage reef-grown algal turfs, to examine turf algal removal by the two species. Surfaces exposed to C. striatus in laboratory experiments exhibited no significant reductions in turf length or area covered by turfing algae. In marked contrast, A. nigrofuscus reduced turf length by 51% and area covered by turfing algae by 15% in 1 h. The gut contents of specimens from the reef revealed that A. nigrofuscus predominantly ingests algae (the dominant item in 79.6-94.7% of gut content quadrats), while C. striatus ingests detritus and sediments (dominant in 99.6-100% of quadrats). Therefore, C. striatus ingests detritus and sediment, leaving mature algal turfs relatively intact, while A. nigrofuscus directly removes and ingests turf algae. The function of C. striatus differs from cropping herbivorous surgeonfishes such as A. nigrofuscus. On coral reefs, C. striatus brush detrital aggregates from algal turfs, removing microorganisms, organic detritus and inorganic sediment. Confusion over the functional role of C. striatus may stem from an inability to fit it into a single functional category.

  5. Complete and rapid reversal of the body color pattern in juveniles of the convict surgeonfish Acanthurus triostegus at Moorea Island (French Polynesia)

    NASA Astrophysics Data System (ADS)

    Besson, Marc; Salis, Pauline; Laudet, Vincent; Lecchini, David

    2018-03-01

    Color polymorphism is widespread in animals and can be associated with temporary adjustments to environmental variables (phenotypic plasticity). In teleost fishes, one of the most remarkable examples of color plasticity is background adaptation in flatfishes. However, such rapid and complete changes in body color and pattern remain relatively unreported in other species. The convict surgeonfish Acanthurus triostegus is a gregarious species whose body color pattern consists of black vertical bars on a whitish body. Here, we describe an entirely reverse body color pattern (white vertical bars on a blackish body) that we observed in some A. triostegus juveniles in a nursery area at Moorea Island, French Polynesia. In aquaria, we determined that change from one color pattern to the other is rapid, reversible, and corresponds to phenotypic plasticity associated with aggressive behavior.

  6. Revisiting the functional roles of the surgeonfish Acanthurus nigrofuscus and Ctenochaetus striatus

    NASA Astrophysics Data System (ADS)

    Marshell, A.; Mumby, P. J.

    2012-12-01

    Investigating the functional role of herbivorous fish species is important for understanding reef resilience and developing targeted management plans. Among the most abundant fish species on Indo-Pacific coral reefs are the surgeonfishes Acanthurus nigrofuscus and Ctenochaetus striatus. A. nigrofuscus is an herbivorous grazer that crops filamentous algae from the epilithic algal matrix, while C. striatus is detritivorous and was thought to `brush' detritus from the surface of filamentous algae, causing little damage to algal strands. Although the foraging mechanisms and general diet of these surgeonfishes have been established, their grazing impact on epilithic algal turfs has been unclear. This is the first study to quantify the grazing impact of A. nigrofuscus and C. striatus on algal turfs. Through aquaria trials using epilithic algal turf grown on experimental tiles, we found that both A. nigrofuscus and C. striatus consistently fed more intensively upon sparse/short algal turfs even though the yield of algae per bite was greater for dense/long algal turfs. As there was no difference in the nutritional value of sparse and dense algal turfs, we hypothesise that A. nigrofuscus avoided dense turf due to its significantly greater sediment load than sparse turf, while C. striatus likely avoided dense turf as it would become entangled in their bristle-like teeth. Unexpectedly, despite its dental morphology, C. striatus removed significantly more algal turf per hour than A. nigrofuscus, irrespective of canopy height. The capability of C. striatus to remove significant quantities of algal turf through their foraging activity implies that this abundant and widespread species may substantially affect algal turf dynamics. If this is the case, the exclusion of detritivorous Ctenochaetus species from herbivorous fish functional groups used in resilience monitoring will need to be re-evaluated.

  7. First record of Puerulus mesodontus Chan, Ma & Chu, 2013 (Crustacea, Decapoda, Achelata, Palinuridae) from south of Java, Indonesia.

    PubMed

    Wardiatno, Yusli; Hakim, Agus Alim; Mashar, Ali; Butet, Nurlisa Alias; Adrianto, Luky; Farajallah, Achmad

    2016-01-01

    Three specimens of Puerulus mesodontus Chan, Ma & Chu, 2013 (Crustacea, Decapoda, Achelata, Palinuridae) were collected from Palabuhanratu Bay, southern Java, Indonesia. There is no previous record on the presence of the species in Indonesia. This finding represents the first record of this species in Java, Indonesia, and confirms that the species is present in the Indian Ocean. The morphological characters of the species are described. This paper contains a new distribution record of a lobster species from Indonesian waters.

  8. First stage larva of the mud shrimp Nihonotrypaea makarovi Marin, 2013
    (Decapoda: Axiidea: Callianassidae) obtained in the laboratory.

    PubMed

    Korn, Olga M; Kornienko, Elena S; Golubinskaya, Darya D

    2016-02-19

    First stage larva of a new mud shrimp Nihonotrypaea makarovi Marin, 2013 (Decapoda: Axiidea: Callianassidae) obtained from the ovigerous female is described and illustrated for the first time. The first zoea of N. makarovi is well distinguished from the first larvae of N. japonica and N. petalura, sympatric callianassid species inhabiting Russian waters of the Sea of Japan, only by the greater size and by the presence of two terminal setae on the antennal endopod.

  9. First record of Naushonia sp. (Decapoda: Laomediidae) larva from the Equatorial Atlantic.

    PubMed

    De Albuquerque Lira, Simone Maria; De Santana, Claudeilton Severino; Schwamborn, Ralf

    2018-02-26

    The first zoeal-stage larva of a possibly new species of mud shrimp Naushonia (Decapoda: Gebiidea: Laomediidae) was described from plankton samples taken off the Fernando de Noronha Archipelago, being the first occurrence at the oceanic islands of the Equatorial Atlantic. Five zoea I larvae were obtained and dissected for observation of mouthparts. This zoea I of Naushonia sp. is well distinguished from the first larvae of N. portoricensis (Rathbun 1901) from the Caribbean and N. cangronoides (Kingsley 1897) from the Northwest Atlantic in terms of development and setation of appendages, and possibly belongs to a new, undescribed species. The present study widens the knowledge on tropical oceanic decapod larvae and provides detailed drawings and new photographic illustrations with extended depth of field of these organisms.

  10. Not All Larvae Stay Close to Home: Insights into Marine Population Connectivity with a Focus on the Brown Surgeonfish (Acanthurus nigrofuscus)

    PubMed Central

    Eble, Jeff A.; Rocha, Luiz A.; Craig, Matthew T.; Bowen, Brian W.

    2014-01-01

    Recent reports of localized larval recruitment in predominately small-range fishes are countered by studies that show high genetic connectivity across large oceanic distances. This discrepancy may result from the different timescales over which genetic and demographic processes operate or rather may indicate regular long-distance dispersal in some species. Here, we contribute an analysis of mtDNA cytochrome b diversity in the widely distributed Brown Surgeonfish (Acanthurus nigrofuscus; N = 560), which revealed significant genetic structure only at the extremes of the range (ΦCT = 0.452; P < .001). Collections from Hawaii to the Eastern Indian Ocean comprise one large, undifferentiated population. This pattern of limited genetic subdivision across reefs of the central Indo-Pacific has been observed in a number of large-range reef fishes. Conversely, small-range fishes are often deeply structured over the same area. These findings demonstrate population connectivity differences among species at biogeographic and evolutionary timescales, which likely translates into differences in dispersal ability at ecological and demographic timescales. While interspecific differences in population connectivity complicate the design of management strategies, the integration of multiscale connectivity patterns into marine resource planning will help ensure long-term ecosystem stability by preserving functionally diverse communities. PMID:25505914

  11. Evolution and phylogeny of the mud shrimps (Crustacea: Decapoda) revealed from complete mitochondrial genomes.

    PubMed

    Lin, Feng-Jiau; Liu, Yuan; Sha, Zhongli; Tsang, Ling Ming; Chu, Ka Hou; Chan, Tin-Yam; Liu, Ruiyu; Cui, Zhaoxia

    2012-11-16

    The evolutionary history and relationships of the mud shrimps (Crustacea: Decapoda: Gebiidea and Axiidea) are contentious, with previous attempts revealing mixed results. The mud shrimps were once classified in the infraorder Thalassinidea. Recent molecular phylogenetic analyses, however, suggest separation of the group into two individual infraorders, Gebiidea and Axiidea. Mitochondrial (mt) genome sequence and structure can be especially powerful in resolving higher systematic relationships that may offer new insights into the phylogeny of the mud shrimps and the other decapod infraorders, and test the hypothesis of dividing the mud shrimps into two infraorders. We present the complete mitochondrial genome sequences of five mud shrimps, Austinogebia edulis, Upogebia major, Thalassina kelanang (Gebiidea), Nihonotrypaea thermophilus and Neaxius glyptocercus (Axiidea). All five genomes encode a standard set of 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and a putative control region. Except for T. kelanang, mud shrimp mitochondrial genomes exhibited rearrangements and novel patterns compared to the pancrustacean ground pattern. Each of the two Gebiidea species (A. edulis and U. major) and two Axiidea species (N. glyptocercus and N. thermophiles) share unique gene order specific to their infraorders and analyses further suggest these two derived gene orders have evolved independently. Phylogenetic analyses based on the concatenated nucleotide and amino acid sequences of 13 protein-coding genes indicate the possible polyphyly of mud shrimps, supporting the division of the group into two infraorders. However, the infraordinal relationships among the Gebiidea and Axiidea, and other reptants are poorly resolved. The inclusion of mt genome from more taxa, in particular the reptant infraorders Polychelida and Glypheidea is required in further analysis. Phylogenetic analyses on the mt genome sequences and the distinct gene orders provide further

  12. The larval development of the partner shrimp Periclimenes sagittifer (Norman, 1861) (Decapoda: Caridea: Palaemonidae: Pontoniinae) described from laboratory-reared material, with a note on chemical settlement cues

    NASA Astrophysics Data System (ADS)

    dos Santos, Antonina; Calado, Ricardo; Bartilotti, Cátia; Narciso, Luís

    2004-04-01

    The complete larval development (eight zoeae and megalopa) of Periclimenes sagittifer (Norman, 1861) (Decapoda: Palaemonidae: Pontoniinae) from laboratory-reared material is described and illustrated. The morphology of the first larval stage is compared with previous larval descriptions of other species in the genus (P. agag, P. americanus, P. calmani, P. diversipes, P. grandis and P. pandionis). The importance of chemical settlement cues for late stage Periclimenes larvae is discussed.

  13. Evolution and phylogeny of the mud shrimps (Crustacea: Decapoda) revealed from complete mitochondrial genomes

    PubMed Central

    2012-01-01

    Background The evolutionary history and relationships of the mud shrimps (Crustacea: Decapoda: Gebiidea and Axiidea) are contentious, with previous attempts revealing mixed results. The mud shrimps were once classified in the infraorder Thalassinidea. Recent molecular phylogenetic analyses, however, suggest separation of the group into two individual infraorders, Gebiidea and Axiidea. Mitochondrial (mt) genome sequence and structure can be especially powerful in resolving higher systematic relationships that may offer new insights into the phylogeny of the mud shrimps and the other decapod infraorders, and test the hypothesis of dividing the mud shrimps into two infraorders. Results We present the complete mitochondrial genome sequences of five mud shrimps, Austinogebia edulis, Upogebia major, Thalassina kelanang (Gebiidea), Nihonotrypaea thermophilus and Neaxius glyptocercus (Axiidea). All five genomes encode a standard set of 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and a putative control region. Except for T. kelanang, mud shrimp mitochondrial genomes exhibited rearrangements and novel patterns compared to the pancrustacean ground pattern. Each of the two Gebiidea species (A. edulis and U. major) and two Axiidea species (N. glyptocercus and N. thermophiles) share unique gene order specific to their infraorders and analyses further suggest these two derived gene orders have evolved independently. Phylogenetic analyses based on the concatenated nucleotide and amino acid sequences of 13 protein-coding genes indicate the possible polyphyly of mud shrimps, supporting the division of the group into two infraorders. However, the infraordinal relationships among the Gebiidea and Axiidea, and other reptants are poorly resolved. The inclusion of mt genome from more taxa, in particular the reptant infraorders Polychelida and Glypheidea is required in further analysis. Conclusions Phylogenetic analyses on the mt genome sequences and the

  14. A review of Epipenaeon ingens Nobili, 1906 (Isopoda: Bopyridae) host species and documentation of a new host, Metapenaeopsis stridulans (Alcock, 1905) (Decapoda: Penaeidae)

    NASA Astrophysics Data System (ADS)

    Rajkumar, M.; Manokaran, S.; Sun, Jun; Trilles, J. P.

    2011-01-01

    We collected 3 596 Metapenaeopsis stridulans (Decapoda: Penaeidae) from the southeast coast of India between January and December 2007. Sixty three specimens (43 females and 18 males) were parasitized by the bopyrid isopod Epipenaeon ingens (Isopoda: Bopyridae). This is the first report of the occurrence of E. ingens in this host; therefore, it was considered as a new host record. The highest level of infestation (3.2%) occurred in October 2007, coincident with observations of gravid females (9). The total prevalence and presence of gravid females were 17.46% and 28%, respectively. Infestation caused a characteristic bulge of the branchial chamber, growth retardation, and degeneration of the sex organs, but had no effect on the host weight.

  15. Treatment factors influencing the use of recombinant platelet-derived growth factor (Regranex) for head and lateral line erosion syndrome in ocean surgeonfish (Acanthurus bahianus).

    PubMed

    Fleming, Gregory J; Corwin, Allison; McCoy, A Jeanene; Stamper, M Andrew

    2008-06-01

    The clinical efficacy of becaplermin (Regranex, Ortho-McNeil Pharmaceutical, Inc., Raritan, New Jersey 08869) on head and lateral line erosion syndrome (HLLES) in ocean surgeonfish (Acanthurus bahianus) was examined in a two-part study to determine suitable application frequencies of the drug and the effects of the environment on outcome of treatments. In the first part of the study, 12 ocean surgeonfish with prior HLLES were equally divided into three treatment groups, varying in application frequency of becaplermin: 1) one application, 2) three applications every 3 wk, and 3) no applications. After 9 wk, it was determined through photograph and computer analysis that fish treated with becaplermin did heal significantly more than the fish that were not treated. No significant difference was found when comparing the two treatment regimes; therefore, a one-time treatment of becaplermin was just as effective as the three-time application, reducing cost of the treatment, staff labor, and stress to the animals. In the second part of the study, the effect of the water environment on HLLES development was documented before and after a one-time treatment of becaplermin. When fish were treated and placed into a system known to cause HLLES, the becaplermin treatment had no effect on reducing the HLLES progression, whereas treated fish that were placed into a system that did not cause HLLES showed a significant decrease in erosion after the treatment. Therefore, treating fish being placed into a HLLES-causing system serves no beneficial purpose to healing HLLES.

  16. Lilliput effect in a retroplumid crab (Crustacea: Decapoda) across the K/Pg boundary

    NASA Astrophysics Data System (ADS)

    Martínez-Díaz, José Luis; Phillips, George E.; Nyborg, Torrey; Espinosa, Belinda; Távora, Vladimir de Araújo; Centeno-García, Elena; Vega, Francisco J.

    2016-08-01

    The genus Costacopluma (Brachyura: Decapoda: Retroplumidae) had a wide distribution during the early Paleogene and is currently represented by 14 species across the Late Cretaceous and early Paleogene. Described early Paleogene species have a smaller mean body size compared to Campanian-Maastrichtian populations of Africa, northeastern Mexico, and southeastern United States. Originally described from the Paleocene and Eocene of Alabama, Costacopluma grayi Feldmann and Portell, 2007, is now documented from the uppermost Maastrichtian (66.2 Ma) of northeastern Mexico and Mississippi and Lower Paleocene of Arkansas, all representing medium size specimens. The morphological features of latest Maastrichtian (66.2 Ma) individuals are identical to those observed among populations of C. grayi from the Paleogene of Alabama and Arkansas, which have a smaller mean size. This size reduction, or dwarfism, in C. grayi across the K-Pg boundary is an example of the Lilliput effect. Dwarfism has been documented in several invertebrate groups as a response to environmental stress, but this is the first record of the Lilliput effect in brachyuran crustaceans. The stratigraphic and geographic range for Costacopluma mexicana Vega and Perrilliat, 1989, is extended to the upper Campanian in northeastern Mexico and lower Maastrichtian in Mississippi and is suggested as a possible ancestor of C. grayi. Different preservational modes for this species in northeastern Mexico are discussed.

  17. Occurrence and behaviour of Paromola cuvieri (Crustacea, Decapoda) in the Santa Maria di Leuca cold-water coral community (Mediterranean Sea)

    NASA Astrophysics Data System (ADS)

    Capezzuto, Francesca; Maiorano, Porzia; Panza, Michele; Indennidate, Antonella; Sion, Letizia; D'Onghia, Gianfranco

    2012-01-01

    Occurrence and behaviour of Paromola cuvieri (Crustacea, Decapoda) were recorded by means of the MEMO lander equipped with two digital cameras and deployed in the cold-water coral community of the Santa Maria di Leuca (Mediterranean Sea). A total of 14 individuals were observed at depths between 547 and 648 m; 10 in the coral habitat on coral mounds and 4 off the coral habitat on muddy bottoms. Thirteen specimens recorded were females, one male and all were shown to scavenge the bait. All the specimens carried a sponge on their exoskeleton using the fifth pereiopods. The specimens were distinguishable by the size and shape of the carried sponge. The present observations demonstrate both passive covering behaviour and active behaviour of discouraging approach and attack from competitors or predators, respectively. This study represents the first in situ documentation of Paromola cuvieri behaviour interacting with other deep-sea species in the Mediterranean Sea.

  18. Oldest record of Mathildellidae (Crustacea: Decapoda: Goneplacoidea) associated with Retroplumidae from the Upper Cretaceous of NE Mexico

    NASA Astrophysics Data System (ADS)

    Vega, Francisco J.; Ahyong, Shane T.; Espinosa, Belinda; Flores-Ventura, José; Luna, Laura; González-González, Arturo H.

    2018-03-01

    A new genus and species of the Mathildellidae Prebranchioplax cretacica (Crustacea: Decapoda: Goneplacoidea) is reported from shallow marine sediments of the upper Campanian Parras Shale and Cerro del Pueblo Formation (Parras Basin), Coahuila, NE Mexico. Prebranchioplax cretacica was collected from siliceous concretions associated with more abundant specimens of the retroplumid Costacopluma mexicana Vega and Perrilliat, 1989. P. cretacica bears similarities to Eocene species of Branchioplax from Japan, USA (Alaska and Washington), England, Hungary and Tajikistan as well as with Eogeryonidae (Portunoidea) species from the Upper Cretaceous of Spain and Marocarcinidae (Styracocarcinus) from Morocco. However, clear differences in the carapace frontal shape places P. cretacica in the Mathildellidae. This record represents the oldest known Mathildellidae, and along with the Retroplumidae, appear to have originated during the Late Cretaceous in ancient seas of Mexico, with a wide distribution during Paleogene times becoming restricted today to deep waters of the Indo-Pacific region and Atlantic Ocean. Comments on preservation and morphology of Costacopluma mexicana are also included. Crab specimens preserved in siliceous concretions from one locality (Entronque) show peculiar desiccation marks, and a possible model of taphonomy.

  19. A new microsporidium, Triwangia caridinae gen. nov., sp. nov. parasitizing fresh water shrimp, Caridina formosae (Decapoda: Atyidae) in Taiwan.

    PubMed

    Wang, Tai-Chuan; Nai, Yu-Shin; Wang, Chih-Yuan; Solter, Leellen F; Hsu, Hui-Chen; Wang, Chung-Hsiung; Lo, Chu-Fang

    2013-03-01

    A new microsporidium was isolated from the endemic, Taiwanese shrimp, Caridina formosae (Decapoda, Atyidae) from northern Taiwan. A conspicuous symptom of infection was presence of opaque white xenomas located in the proximity of the alimentary tract, the surface of the hepatopancreas, and the gills. A fully developed xenoma consisted of a hard, thick capsule filled with sporophorous vesicles containing multiple spores. Microsporidia developed synchronously within the same sporophorous vesicle, although the stage of parasite development differed among the vesicles. Fresh spores were pyriform, mononucleated and measured 6.53 × 4.38 μm. The polar filament was anisofilar with 9-11 coils. Phylogenetic analysis based on the small subunit ribosomal DNA sequence showed that the isolate is most similar to the fish microsporidian clade containing the genera Kabatana, Microgemma, Potaspora, Spraguea, and Teramicra. The highest sequence identity, 80%, was with Spraguea spp. Based on pathogenesis, life cycle and phylogenetic analysis, we erect a new genus and species, Triwangia caridinae for the novel microsporidium. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. First inventory of the Crustacea (Decapoda, Stomatopoda) of Juan de Nova Island with ecological observations and comparison with nearby islands in the Mozambique channel (Europa, Glorieuses, Mayotte)

    NASA Astrophysics Data System (ADS)

    Poupin, J.

    2016-04-01

    Crustacea Decapoda and Stomatopoda are inventoried for the first time in Juan de Nova Island, Iles Eparses, Mozambique channel. In total, 112 species are reported: 69 crabs, 28 anomurans, 11 shrimps, 3 mantis shrimps and 1 lobster. A comparison is made with nearby islands in the Mozambique channel: Glorieuses Islands (157 species), Europa Island (178 species), and Mayotte Island (505 species). The lower species richness at Juan de Nova is explained by the small size of the island and by the difficulties to collect the crustaceans on the reef flat hardly accessible at low tide. The crustaceans are listed by main habitats from land to outer reef (2-20 m). The presence of the coconut crab (Birgus latro), an endangered species vulnerable to human predation, is confirmed.

  1. Comparative Ultrastructure and Carbohydrate Composition of Gastroliths from Astacidae, Cambaridae and Parastacidae Freshwater Crayfish (Crustacea, Decapoda)

    PubMed Central

    Luquet, Gilles; Fernández, María S.; Badou, Aïcha; Guichard, Nathalie; Roy, Nathalie Le; Corneillat, Marion; Alcaraz, Gérard; Arias, José L.

    2012-01-01

    Crustaceans have to cyclically replace their rigid exoskeleton in order to grow.Most of them harden this skeleton by a calcification process. Some decapods (land crabs, lobsters and crayfish) elaborate calcium storage structures as a reservoir of calcium ions in their stomach wall, as so-called gastroliths. For a better understanding of the cyclic elaboration of these calcium deposits, we studied the ultrastructure of gastroliths from freshwater crayfish by using a combination of microscopic and physical techniques. Because sugars are also molecules putatively involved in the elaboration process of these biomineralizations, we also determined their carbohydrate composition. This study was performed in a comparative perspective on crayfish species belonging to the infra-order Astacidea (Decapoda, Malacostraca): three species from the Astacoidea superfamily and one species from the Parastacoidea superfamily. We observed that all the gastroliths exhibit a similar dense network of protein-chitin fibers, from macro- to nanoscale, within which calcium is precipitated as amorphous calcium carbonate. Nevertheless, they are not very similar at the molecular level, notably as regards their carbohydrate composition. Besides glucosamine, the basic carbohydrate component of chitin, we evidenced the presence of other sugars, some of which are species-specific like rhamnose and galacturonic acid whereas xylose and mannose could be linked to proteoglycan components. PMID:24970155

  2. The biogeography of the yeti crabs (Kiwaidae) with notes on the phylogeny of the Chirostyloidea (Decapoda: Anomura)

    PubMed Central

    Roterman, C. N.; Copley, J. T.; Linse, K. T.; Tyler, P. A.; Rogers, A. D.

    2013-01-01

    The phylogeny of the superfamily Chirostyloidea (Decapoda: Anomura) has been poorly understood owing to limited taxon sampling and discordance between different genes. We present a nine-gene dataset across 15 chirostyloids, including all known yeti crabs (Kiwaidae), to improve the resolution of phylogenetic affinities within and between the different families, and to date key divergences using fossil calibrations. This study supports the monophyly of Chirostyloidea and, within this, a basal split between Eumunididae and a Kiwaidae–Chirostylidae clade. All three families originated in the Mid-Cretaceous, but extant kiwaids and most chirostylids radiated from the Eocene onwards. Within Kiwaidae, the basal split between the seep-endemic Kiwa puravida and a vent clade comprising Kiwa hirsuta and Kiwa spp. found on the East Scotia and Southwest Indian ridges is compatible with a hypothesized seep-to-vent evolutionary trajectory. A divergence date estimate of 13.4–25.9 Ma between the Pacific and non-Pacific lineages is consistent with Kiwaidae spreading into the Atlantic sector of the Southern Ocean via the newly opened Drake Passage. The recent radiation of Kiwaidae adds to the list of chemosynthetic fauna that appear to have diversified after the Palaeocene/Eocene Thermal Maximum, a period of possibly widespread anoxia/dysoxia in deep-sea basins. PMID:23782878

  3. Introduction of non-native marine fish species to the Canary Islands waters through oil platforms as vectors

    NASA Astrophysics Data System (ADS)

    Pajuelo, José G.; González, José A.; Triay-Portella, Raül; Martín, José A.; Ruiz-Díaz, Raquel; Lorenzo, José M.; Luque, Ángel

    2016-11-01

    This work documents the introduction of non-native fish species to the Canary Islands (central-eastern Atlantic) through oil rigs. Methodological approaches have included surveys by underwater visual censuses around and under oil platforms and along the docking area of rigs at the Port of Las Palmas. Eleven non-native fish species were registered. Paranthias furcifer, Abudefduf hoefleri, Acanthurus bahianus, Acanthurus chirurgus, and Acanthurus coeruleus are first recorded from the Canaries herein. Other three species could not be identified, although they have never been observed in the Canaries. Cephalopholis taeniops, Abudefduf saxatilis, and Acanthurus monroviae had been previously recorded. Native areas of these species coincide with the areas of origin and the scale of oil rigs with destination the Port of Las Palmas. The absence of native species in the censuses at rigs and their presence at rigs docking area, together with the observation of non-native species after the departure of platforms, reject the possibility that these non-native species were already present in the area introduced by another vector. C. taeniops, A. hoefleri, A. saxatilis, A. chirurgus, A. coeruleus and A. monroviae are clearly seafarer species. A. bahianus seems to be a potential seafarer species. P. furcifer is a castaway species. For the moment, the number of individuals of the non-native species in marine ecosystems of the Canaries seems to be low, and more investigation is needed for controlling these translocations.

  4. Bruce Wiegman with a tether for the Electostatic Propulsion System.

    NASA Image and Video Library

    2015-09-30

    BRUCE WIEGMANN, AN ENGINEER AT NASA'S MARSHALL SPACE FLIGHT CENTER IN HUNTSVILLE, ALABAMA, EXAMINES A HAIR-THIN TETHER THAT WILL BE PART OF AN ELECTROSTATIC PROPULSION SYSTEM THAT COULD SEND SPACECRAFT ON INTERSTELLAR MISSIONS.

  5. Bibliography of Publications 1979-1985, Reports 1955-1985, Theses 1978-1985.

    DTIC Science & Technology

    1987-05-01

    J. Gonor. 1982. The tidal exchange of Callianassa californiensis (Crustacea: Decapoda ) larvae between the ocean and the Salmon River estuary, Oregon...Pandalus iordani ( Decapoda , Pandalidae) larvae off the Oregon coast. Fishery Bull. 81:455-472. Miller, C. B., B. W. Frost, H. P. Batchelder, M. Clemons...known Si requirement. II. Strong pH dependence of uptake kinetic parameters in Phaeodactylum Tricornutum (Bacillariophyceae). J. Phycology 21:168-171

  6. Multiobjective Topology Optimization of Energy Absorbing Materials

    DTIC Science & Technology

    2015-08-01

    absorbing liner for equestrian helmets. Part I: layered foam liner . Mater Des 30(9):3405–3413 Sethian J, Wiegmann A (2000) Structural boundary design via...Army Research Laboratory Wildman RA, Weile DS (2007) Geometry reconstruction of conduct- ing cylinders using genetic programming. IEEE Trans Antennas

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fistul, M. V.; Vinokur, V. M.; Baturina, T. I.

    M.V. Fistul, V.M. Vinokur, and T.I. Baturina wrote a paper titled 'Collective Cooper-Pair Transport in the Insulating State of Josephson-Junction Arrays' which K.B. Efetov, M.V. Feigelman, and P.B. Wiegmann then made comments on that paper and this is Fistul, Vinokur, and Baturina's reply.

  8. The little shrimp that could: phylogeography of the circumtropical Stenopus hispidus (Crustacea: Decapoda), reveals divergent Atlantic and Pacific lineages

    PubMed Central

    Iacchei, Matthew; Coleman, Richard R.; Gaither, Michelle R.; Browne, William E.; Bowen, Brian W.; Toonen, Robert J.

    2018-01-01

    The banded coral shrimp, Stenopus hispidus (Crustacea: Decapoda: Stenopodidea) is a popular marine ornamental species with a circumtropical distribution. The planktonic larval stage lasts ∼120–253 days, indicating considerable dispersal potential, but few studies have investigated genetic connectivity on a global scale in marine invertebrates. To resolve patterns of divergence and phylogeography of S. hispidus, we surveyed 525 bp of mitochondrial cytochrome c oxidase subunit I (COI) from 198 individuals sampled at 10 locations across ∼27,000 km of the species range. Phylogenetic analyses reveal that S. hispidus has a Western Atlantic lineage and a widely distributed Indo-Pacific lineage, separated by sequence divergence of 2.1%. Genetic diversity is much higher in the Western Atlantic (h = 0.929; π = 0.004) relative to the Indo-Pacific (h = 0.105; π < 0.001), and coalescent analyses indicate that the Indo-Pacific population expanded more recently (95% HPD (highest posterior density) = 60,000–400,000 yr) than the Western Atlantic population (95% HPD = 300,000–760,000 yr). Divergence of the Western Atlantic and Pacific lineages is estimated at 710,000–1.8 million years ago, which does not readily align with commonly implicated colonization events between the ocean basins. The estimated age of populations contradicts the prevailing dispersal route for tropical marine biodiversity (Indo-Pacific to Atlantic) with the oldest and most diverse population in the Atlantic, and a recent population expansion with a single common haplotype shared throughout the vast Indian and Pacific oceans. In contrast to the circumtropical fishes, this diminutive reef shrimp challenges our understanding of conventional dispersal capabilities of marine species. PMID:29527409

  9. Systematic and Evolutionary Insights Derived from mtDNA COI Barcode Diversity in the Decapoda (Crustacea: Malacostraca)

    PubMed Central

    Matzen da Silva, Joana; Creer, Simon; dos Santos, Antonina; Costa, Ana C.; Cunha, Marina R.; Costa, Filipe O.; Carvalho, Gary R.

    2011-01-01

    Background Decapods are the most recognizable of all crustaceans and comprise a dominant group of benthic invertebrates of the continental shelf and slope, including many species of economic importance. Of the 17635 morphologically described Decapoda species, only 5.4% are represented by COI barcode region sequences. It therefore remains a challenge to compile regional databases that identify and analyse the extent and patterns of decapod diversity throughout the world. Methodology/Principal Findings We contributed 101 decapod species from the North East Atlantic, the Gulf of Cadiz and the Mediterranean Sea, of which 81 species represent novel COI records. Within the newly-generated dataset, 3.6% of the species barcodes conflicted with the assigned morphological taxonomic identification, highlighting both the apparent taxonomic ambiguity among certain groups, and the need for an accelerated and independent taxonomic approach. Using the combined COI barcode projects from the Barcode of Life Database, we provide the most comprehensive COI data set so far examined for the Order (1572 sequences of 528 species, 213 genera, and 67 families). Patterns within families show a general predicted molecular hierarchy, but the scale of divergence at each taxonomic level appears to vary extensively between families. The range values of mean K2P distance observed were: within species 0.285% to 1.375%, within genus 6.376% to 20.924% and within family 11.392% to 25.617%. Nucleotide composition varied greatly across decapods, ranging from 30.8 % to 49.4 % GC content. Conclusions/Significance Decapod biological diversity was quantified by identifying putative cryptic species allowing a rapid assessment of taxon diversity in groups that have until now received limited morphological and systematic examination. We highlight taxonomic groups or species with unusual nucleotide composition or evolutionary rates. Such data are relevant to strategies for conservation of existing decapod

  10. Seamount influences on mid-water shrimps (Decapoda) and gnathophausiids (Lophogastridea) of the South-West Indian Ridge

    NASA Astrophysics Data System (ADS)

    Letessier, Tom B.; De Grave, Sammy; Boersch-Supan, Philipp H.; Kemp, Kirsty M.; Brierley, Andrew S.; Rogers, Alex D.

    2017-02-01

    Maintenance of often-observed elevated levels of pelagic diversity and biomass on seamounts, of relevance to conservation and fishery management, involves complex interactions between physical and biological variables that remain poorly understood. To untangle these biophysical processes we explore factors influencing the distribution of epi- and meso-pelagic (0-1000 m) micronektonic crustaceans (>15 mm; order Lophogastridea, family Gnathophausiidea; and order Decapoda) on and off seamounts along the South West Indian Ridge (SWIR, 27° to 42°S) and on a seamount off the Madagascar Ridge (31.6°S, 42.8°E). Thirty-one species of micronektic crustaceans were caught using mid-water trawls within the study area but there was no apparent latitude-related patterns in species richness or abundance. Species richness predicted by rarefraction curves and numerical abundance was highest in the vicinity (<1 km) of seamounts (species richness: 15 to 21; abundance: 10±2 to 20±1 ind.10-3 m-1) compared with over the abyssal plains and ridge slopes (species richness: 9.2-9.9; abundance: 24±2 to 79±8 ind.10-3 m-1). Multivariate analysis of assemblage composition revealed significant groupings of individual trawl samples with respect to whether the sample was on or off a seamount and hydrographic region, but not with time of sampling relative to diel cycle (day/night or dawn) or depth of sampling (0-500, 500-800, >800 m). The dominant species assemblage comprised the shrimps Systellaspis debilis (37%) and Sergia prehensilis (34%), and was restricted to seamounts on the subtropical SWIR. Our observations suggest that the 'oasis effect' of seamounts conventionally associated with higher trophic levels is also applicable to pelagic micronektic crustaceans at lower trophic levels. We suggest that the enhanced biomass and species richness attributed is due to 'habitat enrichment', whereby seamounts provide favourable habitats for both pelagic and bentho-pelagic mid-water crustaceans.

  11. Monogenea of fishes from the lagoon flats of Palmyra Atoll in the Central Pacific

    USGS Publications Warehouse

    Vidal-Martínez, Víctor Manuel; Soler-Jiménez, Lilia Catherinne; Aguirre-Macedo, Ma. Leopoldina; Mclaughlin, John; Jaramillo, Alejandra G.; Shaw, Jenny C.; James, Anna; Hechinger, Ryan F.; Kuris, Armand M.; Lafferty, Kevin D.

    2017-01-01

    A survey of the monogeneans of fishes from the lagoon flats of Palmyra Atoll detected 16 species already reported from the Indo-West Pacific faunal region. A total of 653 individual fish from 44 species were collected from the sand flats bordering the lagoon of the atoll. Eighteen species of fish were infected with monogeneans. The monogenean species recovered were: Benedenia hawaiiensis on Acanthurus xanthopterus, Chaetodon auriga, Chaetodon lunula, Mulloidichthys flavolineatus, Pseudobalistes flavimarginatus and Rhinecanthus aculeatus; Ancyrocephalus ornatus on Arothron hispidus; Euryhaliotrema annulocirrus on Chaetodon auriga and Chaetodon lunula; Euryhaliotrema chrysotaeniae on Lutjanus fulvus; Euryhaliotrema grandis on Chaetodon auriga and Chaetodon lunula; Haliotrema acanthuri on Acanthurus triostegus; Haliotrema aurigae on Chaetodon auriga and Chaetodon lunula; Haliotrema dempsteri on Acanthurus xanthopterus; Haliotrema minutospirale on Mulloidichthys flavolineatus; Haliotrematoides patellacirrus on Lutjanus monostigma; Neohaliotrema bombini on Abudefduf septemfasciatus and Abudefduf sordidus; Acleotrema girellae and Acleotrema parastromatei on Kyphosus cinerascens; Cemocotylella elongata on Caranx ignobilis, Caranx melampygus and Caranx papuensis; Metamicrocotyla macracantha on Crenimugil crenilabris; and Pseudopterinotrema albulae on Albula glossodonta. All these monogenean–host combinations represent new geographical records. The monogenean species composition of the Palmyra Atoll is similar to that of the Hawaiian Islands. However, the number of species recovered was lower compared with other localities within the Indo-West Pacific, perhaps due to the geographical isolation of Palmyra Atoll.

  12. Monogenea of fishes from the lagoon flats of Palmyra Atoll in the Central Pacific

    PubMed Central

    Vidal-Martínez, Víctor Manuel; Soler-Jiménez, Lilia Catherinne; Aguirre-Macedo, Ma. Leopoldina; Mclaughlin, John; Jaramillo, Alejandra G.; Shaw2, Jenny C.; James, Anna; Hechinger, Ryan F.; Kuris, Armand M.; Lafferty, Kevin D.

    2017-01-01

    Abstract A survey of the monogeneans of fishes from the lagoon flats of Palmyra Atoll detected 16 species already reported from the Indo-West Pacific faunal region. A total of 653 individual fish from 44 species were collected from the sand flats bordering the lagoon of the atoll. Eighteen species of fish were infected with monogeneans. The monogenean species recovered were: Benedenia hawaiiensis on Acanthurus xanthopterus, Chaetodon auriga, Chaetodon lunula, Mulloidichthys flavolineatus, Pseudobalistes flavimarginatus and Rhinecanthus aculeatus; Ancyrocephalus ornatus on Arothron hispidus; Euryhaliotrema annulocirrus on Chaetodon auriga and Chaetodon lunula; Euryhaliotrema chrysotaeniae on Lutjanus fulvus; Euryhaliotrema grandis on Chaetodon auriga and Chaetodon lunula; Haliotrema acanthuri on Acanthurus triostegus; Haliotrema aurigae on Chaetodon auriga and Chaetodon lunula; Haliotrema dempsteri on Acanthurus xanthopterus; Haliotrema minutospirale on Mulloidichthys flavolineatus; Haliotrematoides patellacirrus on Lutjanus monostigma; Neohaliotrema bombini on Abudefduf septemfasciatus and Abudefduf sordidus; Acleotrema girellae and Acleotrema parastromatei on Kyphosus cinerascens; Cemocotylella elongata on Caranx ignobilis, Caranx melampygus and Caranx papuensis; Metamicrocotyla macracantha on Crenimugil crenilabris; and Pseudopterinotrema albulae on Albula glossodonta. All these monogenean–host combinations represent new geographical records. The monogenean species composition of the Palmyra Atoll is similar to that of the Hawaiian Islands. However, the number of species recovered was lower compared with other localities within the Indo-West Pacific, perhaps due to the geographical isolation of Palmyra Atoll. PMID:29134039

  13. Ultrafast Physics in Semiconductor Microstructures.

    DTIC Science & Technology

    1988-02-19

    1588(1983). (27) Y. Silberger . P. W. Smith, D. JI Eienberger, D. A. B. Miller, A. C. Gossard, and W. Wiegmann. Opt. Lett. 9, 507(1984). S(28) B...and G. R. Fowles, in High Pressure Physic, and Chemistry , and Air Force Office of Scientific Research No. 86-003 1. edited by R. S. Bradley (Academic

  14. [Immunochemical study of the proteins of various tissues in Crustacea (Decapoda): nature, role, origin].

    PubMed

    Durliat, M

    1983-11-01

    The main proteins of the haemolymph of Crustacea Decapoda have been identified and analysed: haemocyanin, plasma coagulogen, heteroagglutinins, vitellogenins, and molt-related proteins. All these complex components exhibit a high molecular weight and as oligomeric fractions are able to aggregate or dissociate in subunits according to the composition of medium and experimental procedures. Besides their important rôle in the defense mechanism, some proteins are involved in the edification of diverse tissues. They are detected within different compartments: soft integument, calcified carapace and hepatopancreas. They are either in transit or sequestered or synthetized within these tissues. In the crayfish Astacus leptodactylus, some components have been identified in different compartments: --in aqueous extracts from soft integument: the haemocyanin, coagulogen and both fraction F1 (lipoprotein with an approximate molecular weight of 45 kdal) and fraction F2 related to the molt. Both coagulogen and fraction F2 appear sometimes as melanized. These two latter fractions exhibit some glucose-mannose residues and they occur with a higher relative amount than in the blood. --in soluble extracts from calcified cuticle: among the numerous fractions showing a high molecular weight, the haemocyanin and coagulogen are detected. --in aqueous extracts from hepatopancreas: both haemocyanin and coagulogen appear with a little relative amount. Components termed as Fa and Fb are found with a high concentration. One minor fraction is also detected. --in aqueous extracts from eggs: the haemocyanin and fraction Fb are present. Other proteins showing only some antigenic identities with those of the haemolymph are also detected in all these tissues. The haemolymph proteins are not present within these compartments following a passive diffusion. Indeed, their relative amount varies according to the tissue investigated and is different from that found in the blood. Except the haemocyanin

  15. DIRS1-like retrotransposons are widely distributed among Decapoda and are particularly present in hydrothermal vent organisms

    PubMed Central

    Piednoël, Mathieu; Bonnivard, Eric

    2009-01-01

    the first time a widespread distribution of these elements among a large phylum, here the order Decapoda. They also suggest some peculiar features of these retrotransposons in hydrothermal organisms where a great diversity of elements is already observed. Finally, this paper constitutes the first essential step which allows for considering further studies based on the dynamics of the DIRS1-like retrotransposons among several genomes. PMID:19400949

  16. DIRS1-like retrotransposons are widely distributed among Decapoda and are particularly present in hydrothermal vent organisms.

    PubMed

    Piednoël, Mathieu; Bonnivard, Eric

    2009-04-28

    distribution of these elements among a large phylum, here the order Decapoda. They also suggest some peculiar features of these retrotransposons in hydrothermal organisms where a great diversity of elements is already observed. Finally, this paper constitutes the first essential step which allows for considering further studies based on the dynamics of the DIRS1-like retrotransposons among several genomes.

  17. An Analysis of U.S. Army Fratricide Incidents during the Global War on Terror (11 September 2001 to 31 March 2008)

    DTIC Science & Technology

    2010-03-15

    Swiss cheese model of human error causation. ................................................................... 3  2. Results for the classification of...based on Reason’s “ Swiss cheese ” model of human error (1990). Figure 1 describes how an accident is likely to occur when all of the errors, or “holes...align. A detailed description of HFACS can be found in Wiegmann and Shappell (2003). Figure 1. The Swiss cheese model of human error

  18. Military Operating Room of the Future

    DTIC Science & Technology

    2012-10-01

    more representative than any single source of data, and a more comprehensive systems analysis than has ever been attempted before. Systems Redesign...Madigan due their Trauma site survey that occurred in June 2011 and the Chief of Surgery, our primary contact, COL Rush, was deployed in Afghanistan from...and nature of flow disruptions allows for the development of evidence-based interventions (Wiegmann, 2006). Flow disruptions collected in a single

  19. In silico prediction of the G-protein coupled receptors expressed during the metamorphic molt of Sagmariasus verreauxi (Crustacea: Decapoda) by mining transcriptomic data: RNA-seq to repertoire.

    PubMed

    Buckley, Sean J; Fitzgibbon, Quinn P; Smith, Gregory G; Ventura, Tomer

    2016-03-01

    Against a backdrop of food insecurity, the farming of decapod crustaceans is a rapidly expanding and globally significant source of food protein. Sagmariasus verreauxi spiny lobster, the subject of this study, are decapods of underdeveloped aquaculture potential. Crustacean neuropeptide G-protein coupled receptors (GPCRs) mediate endocrine pathways that are integral to animal fecundity, growth and survival. The potential use of novel biotechnologies to enhance GPCR-mediated physiology may assist in improving the health and productivity of farmed decapod populations. This study catalogues the GPCRs expressed in the early developmental stages, as well as adult tissues, with a view to illuminating key neuropeptide receptors. De novo assembled contiguous sequences generated from transcriptomic reads of metamorphic and post metamorphic S. verreauxi were filtered for seven transmembrane domains, and used as a reference for iterative re-mapping. Subsequent putative GPCR open reading frames (ORFs) were BLAST annotated, categorised, and compared to published orthologues based on phylogenetic analysis. A total of 85 GPCRs were digitally predicted, that represented each of the four arthropod subfamilies. They generally displayed low-level and non-differential metamorphic expression with few exceptions that we examined using RT-PCR and qPCR. Two putative CHH-like neuropeptide receptors were annotated. Three dimensional structural modelling suggests that these receptors exhibit a conserved extracellular ligand binding pocket, providing support to the notion that these receptors co-evolved with their ligands across Decapoda. This perhaps narrows the search for means to increase productivity of farmed decapod populations. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Transcriptional, translational and systemic alterations during the time course of osmoregulatory acclimation in two palaemonid shrimps from distinct osmotic niches.

    PubMed

    Faleiros, Rogério Oliveira; Furriel, Rosa P M; McNamara, John Campbell

    2017-10-01

    Palaemonid shrimps exhibit numerous adaptive strategies, both in their life cycles and in biochemical, physiological, morphological and behavioral characteristics that reflect the wide variety of habitats in which they occur, including species that are of particular interest when analyzing adaptive osmoregulatory strategies. The present investigation evaluates the short- (hours) and long-term (days) time courses of responses of two palaemonid shrimps from separate yet overlapping osmotic niches, Palaemon northropi (marine) and Macrobrachium acanthurus (diadromous, fresh water), to differential salinity challenges at distinct levels of structural organization: (i) transcriptional, analyzing quantitative expression of gill mRNAs that encode for subunits of the Na + /K + -ATPase and V(H + )-ATPase ion transporters; (ii) translational, examining the kinetic behavior of gill Na + /K + -ATPase specific activity; and (iii) systemic, accompanying consequent adjustment of hemolymph osmolality. Palaemon northropi is an excellent hyper-hypo-osmoregulator in dilute and concentrated seawater, respectively. Macrobrachium acanthurus is a strong hyper-regulator in fresh water and hypo-regulates hemolymph osmolality and particularly [Cl - ] in brackish water. Hemolymph hyper-regulation in fresh water (Macrobrachium acanthurus) and dilute seawater (Palaemon northropi) is underlain by augmented expression of both the gill Na + /K + -ATPase and V(H + )-ATPase. In contrast, in neither species is hypo-regulation sustained by changes in Na + /K + -ATPase mRNA expression levels, but rather by regulating enzyme specific activity. The integrated time course of Na + /K + - and V(H + )-ATPase expression and Na + /K + -ATPase activity in the gills of these palaemonid shrimps during acclimation to different salinities reveals versatility in their levels of regulation, and in the roles of these ion transporting pumps in sustaining processes of hyper- and hypo-osmotic and chloride regulation

  1. An improved taxonomic sampling is a necessary but not sufficient condition for resolving inter-families relationships in Caridean decapods.

    PubMed

    Aznar-Cormano, L; Brisset, J; Chan, T-Y; Corbari, L; Puillandre, N; Utge, J; Zbinden, M; Zuccon, D; Samadi, S

    2015-04-01

    During the past decade, a large number of multi-gene analyses aimed at resolving the phylogenetic relationships within Decapoda. However relationships among families, and even among sub-families, remain poorly defined. Most analyses used an incomplete and opportunistic sampling of species, but also an incomplete and opportunistic gene selection among those available for Decapoda. Here we test in the Caridea if improving the taxonomic coverage following the hierarchical scheme of the classification, as it is currently accepted, provides a better phylogenetic resolution for the inter-families relationships. The rich collections of the Muséum National d'Histoire Naturelle de Paris are used for sampling as far as possible at least two species of two different genera for each family or subfamily. All potential markers are tested over this sampling. For some coding genes the amplification success varies greatly among taxa and the phylogenetic signal is highly saturated. This result probably explains the taxon-heterogeneity among previously published studies. The analysis is thus restricted to the genes homogeneously amplified over the whole sampling. Thanks to the taxonomic sampling scheme the monophyly of most families is confirmed. However the genes commonly used in Decapoda appear non-adapted for clarifying inter-families relationships, which remain poorly resolved. Genome-wide analyses, like transcriptome-based exon capture facilitated by the new generation sequencing methods might provide a sounder approach to resolve deep and rapid radiations like the Caridea.

  2. CHARACTERIZATION OF MICROSATELLITE LOCI IN THE EUROPEAN GREEN CRAB (CARCINUS MAENAS)

    EPA Science Inventory

    Carcinus maenas (Decapoda: Portunidae) has proven a highly successful invasive marine species whose potential economic and ecological impacts are of great concern worldwide. Here, we characterize fourteen polymorphic microsatellite loci in C. maenas and its sister species C. Ae...

  3. Magnetotransport in Two Dimensional Electron Systems Under Microwave Excitation and in Highly Oriented Pyrolytic Graphite

    DTIC Science & Technology

    2012-01-01

    Phys. Rev. Lett. 82, 2147 (1999). [89] Y. Zhang, Y. Tan, H. L. Stormer and P. Kim, Nature 438, 10 (2005). [90] J. W. McClure, Phys. Rev. 108, 612 (1957...Phys. 2, 595 (2006). [97] H. L. Stormer , J. P. Eisenstein, A. C. Gossard, W. Wiegmann, and K. Baldwin, Phys. Rev. Lett. 56, 85 (1985). [98] B. A...Sadowski, J. M. Schneider, and M. Potemski, J. Phys.: Cond. Matter 20, 454223 (2008). [108] W. Pan, J. S. Xia, H. L. Stormer , D. C. Tsui, C. L

  4. Species Profiles. Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Gulf of Mexico). GRASS SHRIMP.

    DTIC Science & Technology

    1985-03-01

    8 Salinity .................................................... 8 Brackish-Water shrimp...names ........ Palaemonetes Order ..................... Decapoda p!. ; P. vulgaris; P. intermedius; Family ................. Palaemonidae P.paludosus...Spawning may produce an additional brood, depending on the species or time of The spawning season of grass spawning (Broad and Hubschman 1963; shrimp

  5. MEMBRANOUS LABYRINTH IN BACULOVIRUS-INFECTED CRUSTRACEAN CELLS: POSSIBLE ROLES IN VIRAL REPRODUCTION

    EPA Science Inventory

    The origins and morphogenesis of the membranous labyrinth (ML) in Baculovirus penaei (BP) infected cells of penaeid shrimps (Crustacea:Decapoda) are described. t is hypothesized that, because of the close parallel and concurrent development of the ML and virus reproduction, and o...

  6. The Physics of Very Small Structures.

    DTIC Science & Technology

    1987-01-01

    n4.5818)necting layer o IB A. Vojak, S W Kirchoefer. N Holonyak. Jr., and R. Chin , J. Appl would only increase the width of the connecting AlAs layer...Vcurve (Fig. 2) as the Dapkus, and R. Chin , J. Appl. Phys. S0. 5830119791. second resonance. A C Gossard, W Brown, C. L. Allyn. and W Wiegmann, J Vac. Scis...The above explanation breaks down, but we do not have as yet a satisfactory explanation for this. ’R Chin . N. H’olonyak. G. E Stillman, J Y Tang, and K

  7. Species Profiles. Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest) Crangonid Shrimp

    DTIC Science & Technology

    1989-12-01

    temperature affected survival at different shelter has been suggested as an important salinities and salinity affected survival at mechanism of nutrient...10 Salinity . . . . .. . . . . .. . . . .. . .. . .. . .. .. . .. .. .. .. . .. . . .. . .. . . . . .. . . . 11 Temperature- Salinity ...members of the tribe Caridca by four features Order .................... Decapoda (Figure 3); (1)-the rostrum is very short, Suborder

  8. Muscle water control in crustaceans and fishes as a function of habitat, osmoregulatory capacity, and degree of euryhalinity.

    PubMed

    Freire, Carolina A; Amado, Enelise M; Souza, Luciana R; Veiga, Marcos P T; Vitule, Jean R S; Souza, Marta M; Prodocimo, Viviane

    2008-04-01

    This study aimed at detecting possible patterns in the relationship between Anisosmotic Extracellular Regulation (AER) and Isosmotic Intracellular Regulation (IIR) in crustaceans and teleost fish from different habitats and evolutionary histories in fresh water (FW), thus different osmoregulatory capabilities, and degrees of euryhalinity. Crustaceans used were the hololimnetic FW Aegla schmitti, and Macrobrachium potiuna, the diadromous FW Macrobrachium acanthurus, the estuarine Palaemon pandaliformis and the marine Hepatus pudibundus; fishes used were the FW Corydoras ehrhardti, Mimagoniates microlepis, and Geophagus brasiliensis, and the marine-estuarine Diapterus auratus. The capacity for IIR was assessed in vitro following wet weight changes of isolated muscle slices incubated in anisosmotic saline (~50% change). M. potiuna was the crustacean with the highest capacity for IIR; the euryhaline perciforms G. brasiliensis and D. auratus displayed total capacity for IIR. It is proposed that a high capacity for IIR is required for invading a new habitat, but that it is later lost after a long time of evolution in a stable habitat, such as in the FW anomuran crab A. schmitti, and the Ostariophysian fishes C. ehrhardti and M. microlepis. More recent FW invaders such as the palaemonid shrimps (M. potiuna and M. acanthurus) and the cichlid G. brasiliensis are euryhaline and still display a high capacity for IIR.

  9. [Crustaceans associated to macroalgae in Bajo Pepito, Isla Mujeres, Mexican Caribbean].

    PubMed

    Campos Vázquez, C

    2000-01-01

    Crustaceans associated with macroalgae were collected for one year by scuba diving in Bajo Pepito, Isla Mujeres, mexican Caribbean. A total of 148 organisms were found: three orders, 11 families, 18 genera and 19 species in nine types of associations. The order with highest abundance was Isopoda (112), followed by Amphipoda (20) and Decapoda (16).

  10. Animation of Heliopause Electrostatic Rapid Transport System (HERTS)

    NASA Image and Video Library

    2016-04-20

    Animation of Heliopause Electrostatic Rapid Transport System (HERTS) concept. NASA engineers are conducting tests to develop models for the Heliopause Electrostatic Rapid Transport System. HERTS builds upon the electric sail invention of Dr. Pekka Janhunen of the Finnish Meteorological Institute. An electric sail could potentially send scientific payloads to the edge of our solar system, the heliopause, in less than 10 years. The research is led by Bruce M. Wiegmann, an engineer in the Advanced Concepts Office at NASA's Marshall Space Flight Center. The HERTS E-Sail development and testing is funded by NASA’s Space Technology Mission Directorate through the NASA Innovative Advanced Concepts Program.

  11. Anolis boulengerianus Thominot, 1887, a senior synonym of Anolis isthmicus Fitch, 1978 (Squamata: Dactyloidae).

    PubMed

    De Oca, Adrián Nieto-Montes; Köhler, Gunther; Feria-Ortiz, Manuel

    2014-05-05

    For most of its history, the name Anolis boulengerianus Thominot, 1887 has been regarded as a junior synonym of Anolis nebulosus (Wiegmann, 1834) or Anolis nebuloides Bocourt, 1873. However, a comparison of the syntypes and additional topotypical specimens of A. boulengerianus with three topoparatypes and additional specimens of the species currently referred to as Anolis isthmicus Fitch, 1978 showed that these two names pertain to the same species. Because of the priority principle, A. isthmicus becomes a junior synonym of A. boulengerianus. We provide a redescription of the type series of A. boulengerianus and an updated diagnosis for this taxon relative to all other beta anoles.

  12. Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Gulf of Mexico). Blue Crab.

    DTIC Science & Technology

    1986-06-01

    depending upon the physiological requirements of each particular stage in its life history. Spawning occurs from spring through fall in high salinity ...developed. Carapace about Order .... ............ Decapoda 2.5 times as wide as long, moderately Infraorder .......... ... Brachyura convex and nearly...cent marine waters; salinities in nates with a final ecdysis). After excess of 20.0 ppt are required for insemination, the male continues to

  13. DTNSRDC Library Subject Thesaurus.

    DTIC Science & Technology

    1980-03-01

    COLLISIONS BISTATIC SONAR BT SONAR BIRDS BT VERTEBRATES BITES AND STINGS NT CHICKENS BT WOUNDS AND INJURIES DUCKS GEESE BITUMENS GULLS ST ORGANIC...NT DECAPODA EL SALVADOR GUATEMALA CEPSTRUM TECHNIQUE HONDURAS MEXICO CERAMIC BODIES NICARAGUA RT BODIES PANAMA CERAMIC BONDING CENTRAL EUROPE BT...EJECTORS E EJECTORS(ORDNANCE) EGG ALBUMIN BT ALBUMINS EJECTORS(DRONANCE) BT EJECTORS EGG FO0 YOUNG NT BOMB EJECTORS USE EGGS( CHICKEN ) AND COO

  14. Adult Demography and Larval Processes in Coastal Benthic Populations: Intertidal Barnacles in Southern California and Baja California

    DTIC Science & Technology

    2005-09-01

    mechanism for near-shore concentration and estuarine recruitment of post-larval Penaeus plebejus Hess ( Decapoda , Penaeidae). Estuarine, Coastal and...the physical The dynamics of coastal populations is highly processes that are likely to affect the distribution dependent on the mechanisms and...help. I was lucky to land on a lab where, depending on the lunar phase, time of year, and who knows what other environmental variables, I would find a

  15. Archaeological Surveys and Evaluations of Four Construction Areas in the Vicinity of Fort Jackson, Plaquemines Parish, Louisiana

    DTIC Science & Technology

    1992-04-01

    dependent to some extent on the prolific growth of vegetation in the delta wetlands. Large areas of brackish-to- saline marsh are found today in the study... dependable , readily available food supply, available on short notice when other sources may have been in short supply. Second, the shells represented the...virginica), Rangia (Rangia cuneata and Rangia flexiosa), marsh mussel (Brachidontes spp.), and fiddler crab ( Decapoda yea). Freshwater mollusks (Unio spp

  16. [Diet composition and ontogenetic variation in feeding habits of Cleithenes herzensteini in central Yellow Sea].

    PubMed

    Zhang, Bo

    2007-08-01

    In the bottom trawl surveys in central Yellow Sea from January 2004 to October 2005, 622 samples of plaice Cleithenes herzensteini were collected, and their stomach contents were analyzed. The results indicated that the prey items of the plaice included 11 groups or 38 prey species, but only Crustacea and Lamellibranchia were the most important prey groups, accounting for 99% of the total food composition by percentage of index of relative importance. Euphausia pacific, Crangon affinis and Tellinidae were the dominant prey species. Comparing with the 1980s, the feeding activity of plaice declined significantly, and the diet composition changed. Fishes were no longer the dominant prey, and the proportion of anchovy in the diet decreased. Cluster analysis and two-way contingency table analysis were used to study the ontogenetic variations in the feeding habits of plaice, and the results showed that the feeding activity of plaice did not vary significantly among 7 size classes within the size between 51 mm and 370 mm, but ontogenetic variations were found in the diet composition. In the size class < 119 mm, the diet mainly included Euphausiacea and Decapoda. In the diets of fish with the size between 120 mm and 199 mm, the proportion of Lamellibranchia and fishes increased markedly. In the size class > 200 mm, plaice mainly fed on Decapoda and fishes.

  17. Import and export fluxes of macrozooplankton are taxa- and season-dependent at Jiuduansha marsh, Yangtze River estuary

    NASA Astrophysics Data System (ADS)

    Qin, Haiming; Sheng, Qiang; Chu, Tianjiang; Wang, Sikai; Wu, Jihua

    2015-09-01

    Macrozooplankton may play important roles in influencing nutrient exchange between salt marsh and nearby estuarine ecosystems through predator-prey interactions and their transport by tidal flows. In this study, macrozooplankton transport through year-round monthly sampling was investigated in a salt marsh creek of the Yangtze River estuary. Twenty-one orders of macrozooplankton were captured. Calanoida and Decapoda were dominant and numerically comprised 59.59% and 37.59% respectively of the total captured macrozooplankton throughout the year. Decapoda mainly occurred in April, May and June. In other months, the Calanoida contributed over 90% of the total individuals. The annual Ferrari index (I) for total individual number of macrozooplankton was 0.27, which generally supports the viewpoint that salt marshes are sources of zooplankton. The salt marsh was mainly a source for decapods and mysids, possibly because of larval release in their breeding seasons. The marsh was also a source for amphipods, probably because some benthic forms became transient planktonic forms during tidal water flushing. Copepods and fish larvae exhibited net import into the salt marsh, which may result from predation from salt marsh settlers or retention in the salt marsh. Monthly Ferrari index (I) estimations revealed that the role of the salt marsh as a sink or source of macrozooplankton was time-dependent, which is related to the life history of animals. This study showed that whether the salt marsh zooplankton act as energy importers or exporters is group/taxa-dependent and time-dependent.

  18. Importance of Mangroves, Seagrass Beds and the Shallow Coral Reef as a Nursery for Important Coral Reef Fishes, Using a Visual Census Technique

    NASA Astrophysics Data System (ADS)

    Nagelkerken, I.; van der Velde, G.; Gorissen, M. W.; Meijer, G. J.; Van't Hof, T.; den Hartog, C.

    2000-07-01

    The nursery function of various biotopes for coral reef fishes was investigated on Bonaire, Netherlands Antilles. Length and abundance of 16 commercially important reef fish species were determined by means of visual censuses during the day in six different biotopes: mangrove prop-roots ( Rhizophora mangle) and seagrass beds ( Thalassia testudinum) in Lac Bay, and four depth zones on the coral reef (0 to 3 m, 3 to 5 m, 10 to 15 m and 15 to 20 m). The mangroves, seagrass beds and shallow coral reef (0 to 3 m) appeared to be the main nursery biotopes for the juveniles of the selected species. Mutual comparison between biotopes showed that the seagrass beds were the most important nursery biotope for juvenile Haemulon flavolineatum, H. sciurus, Ocyurus chrysurus, Acanthurus chirurgus and Sparisoma viride, the mangroves for juvenile Lutjanus apodus, L. griseus, Sphyraena barracuda and Chaetodon capistratus, and the shallow coral reef for juvenile H. chrysargyreum, L. mahogoni , A. bahianus and Abudefduf saxatilis. Juvenile Acanthurus coeruleus utilized all six biotopes, while juvenile H. carbonarium and Anisotremus surinamensis were not observed in any of the six biotopes. Although fishes showed a clear preference for a specific nursery biotope, most fish species utilized multiple nursery biotopes simultaneously. The almost complete absence of juveniles on the deeper reef zones indicates the high dependence of juveniles on the shallow water biotopes as a nursery. For most fish species an (partial) ontogenetic shift was observed at a particular life stage from their (shallow) nursery biotopes to the (deeper) coral reef. Cluster analyses showed that closely related species within the families Haemulidae, Lutjanidae and Acanthuridae, and the different size classes within species in most cases had a spatial separation in biotope utilization.

  19. Diversity of small, single-stranded DNA viruses of invertebrates and their chaotic evolutionary past.

    PubMed

    Tijssen, Peter; Pénzes, Judit J; Yu, Qian; Pham, Hanh T; Bergoin, Max

    2016-10-01

    A wide spectrum of invertebrates is susceptible to various single-stranded DNA viruses. Their relative simplicity of replication and dependence on actively dividing cells makes them highly pathogenic for many invertebrates (Hexapoda, Decapoda, etc.). We present their taxonomical classification and describe the evolutionary relationships between various groups of invertebrate-infecting viruses, their high degree of recombination, and their relationship to viruses infecting mammals or other vertebrates. They share characteristics of the viruses within the various families, including structure of the virus particle, genome properties, and gene expression strategy. Copyright © 2016. Published by Elsevier Inc.

  20. Assessment of acute toxicity of carbofuran in Macrobrachium olfersii (Wiegmann, 1836) at different temperature levels.

    PubMed

    Barbieri, Edison; Moreira, Priscila; Luchini, Luiz Alberto; Hidalgo, Karla Ruiz; Muñoz, Alejandro

    2016-01-01

    Carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate; C12H15NO3) is one of the most toxic carbamate pesticides. For acute toxicity of carbofuran, juveniles of Macrobrachium olfersii were exposed to different concentrations of carbofuran using the static renewal method at different temperature levels (15, 20 and 25°C) at pH 7.0. The main purpose of the present study was to detect the acute toxicity of carbofuran to M. olfersii and investigate its effects on oxygen consumption and ammonium excretion; these tests have not been carried out in this species before. First, the acute toxicity - median lethal concentration - of carbofuran to M. olfersii for 24, 48, 72 and 96 h was examined, which resulted in the following values: 1.64, 1.22, 0.86 and 0.42 mg L(-1), respectively. Furthermore, we also found that carbofuran caused an inhibition in oxygen consumption of 60.6, 65.3 and 66.2% with respect to the control. In addition, after separate exposures to carbofuran, elevations in ammonium excretion were more than 500% with respect to the control. © The Author(s) 2013.

  1. Nitrite toxicity to the crayfish Procambarus clarkii

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gutzmer, M.P.; Tomasso, J.R.

    The purpose of this study was to determine the effects of acute nitrite exposure to the crayfish Procambarus clarkii (Decapoda). Specific objectives of this study included (1) determining the 24-, 48-, 72- and 96-h LC-50's of nitrite to crayfish of different weights and genders in freshwater, (2) determining the LC-50's of nitrite to crayfish in water with elevated chloride concentrations, and (3), in order to gain insight into the mechanisms of nitrite toxicity in crayfish, determining hemolymph nitrite concentrations in crayfish exposed to nitrite in freshwater and water with elevated chloride concentrations.

  2. [COMPARATIVE CHARACTERISTICS OF uNOS-POSITIVE STRUCTURES IN THE CNS OF SOME SPECIES OF CRUSTACEANS].

    PubMed

    Chertok, V M; Kotsyuba, E P

    2015-01-01

    We conducted a comparative study of NO-ergic system in the CNS of 10 species of crustaceans subclass Malacostraca, belonging to orders Stomatopoda and Decapoda, with a common habitat in Ussuri Bay (Sea of Japan). Both similar characteristics and differences in content and distribution of universal NO-synthase (uNOS) were revealed in homologous parts of the brain and ventral nerve cord of the investigated species of crustaceans. We discuss the involvement of nitric oxide in the regulation of physiological functions of decapod crustaceans and its role in the processes of adaptation to the environmental conditions.

  3. Predictive models of safety based on audit findings: Part 1: Model development and reliability.

    PubMed

    Hsiao, Yu-Lin; Drury, Colin; Wu, Changxu; Paquet, Victor

    2013-03-01

    This consecutive study was aimed at the quantitative validation of safety audit tools as predictors of safety performance, as we were unable to find prior studies that tested audit validity against safety outcomes. An aviation maintenance domain was chosen for this work as both audits and safety outcomes are currently prescribed and regulated. In Part 1, we developed a Human Factors/Ergonomics classification framework based on HFACS model (Shappell and Wiegmann, 2001a,b), for the human errors detected by audits, because merely counting audit findings did not predict future safety. The framework was tested for measurement reliability using four participants, two of whom classified errors on 1238 audit reports. Kappa values leveled out after about 200 audits at between 0.5 and 0.8 for different tiers of errors categories. This showed sufficient reliability to proceed with prediction validity testing in Part 2. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  4. Hemocytes of the palaemonids Macrobrachium rosenbergii and M. acanthurus, and of the penaeid Penaeus paulensis.

    PubMed

    Gargioni, R; Barracco, M A

    1998-06-01

    The hemocytes of two palaemonids and one penaeid were characterized using light and transmission electron microscopy (TEM). The blood cells in all three species were classified as hyaline hemocytes (HH), small granule hemocytes (SGH), and large granule hemocytes (LGH). The HH are unstable hemocytes with a characteristic high nucleo-cytoplasmic ratio. Their cytoplasm appears particularly dense and has from few to numerous granules that often exhibit a typical striated substructure. In both palaemonids, the great majority of the HH contain numerous granules, whereas in Penaeus paulensis, a small number of these cells have few or no granules. The cytoplasm of some HH of the penaeid exhibits typical electron-dense deposits. The granulocytes, LGH and SGH, contain abundant electron-dense granules that are usually smaller in the SGH. In both hemocyte types, the cytosol, but not the granules, is rich in carbohydrates (PAS positive) and numerous vesicles contain acid phosphatase (Gomori reactive). In all studied shrimps, the SGH and LGH were actively phagocytic when examined on blood cell monolayers incubated with the yeast Saccharomyces cerevisiae. A few mitotic figures (less than 1%) were observed in the granulocytes of P. paulensis, but not in the palaemonids. SGH is the main circulating blood cell type in both palaemonids, whereas HH is predominant in the penaeid. Based on morphological and functional features, it appears that the hyaline and the granular hemocytes of the three shrimp species represent different cell lineages.

  5. Shrimp burrow in tropical seagrass meadows: An important sink for litter

    NASA Astrophysics Data System (ADS)

    Vonk, Jan Arie; Kneer, Dominik; Stapel, Johan; Asmus, Harald

    2008-08-01

    The abundance, burrow characteristics, and in situ behaviour of the burrowing shrimps Neaxius acanthus (Decapoda: Strahlaxiidae) and Alpheus macellarius (Decapoda: Alpheidae) were studied to quantify the collection of seagrass material, to identify the fate of this collected material, and to determine the importance of these burrowing crustaceans in the nutrient (nitrogen and phosphorus) cycling of two tropical seagrass meadows on Bone Batang, South Sulawesi, Indonesia. Alpheus macellarius harvested 0.70 g dry weight (DW) burrow -1 d -1 seagrass material, dominantly by active cutting of fresh seagrass leaves. Neaxius acanthus collected 1.66 g DW burrow -1 d -1, mainly detached leaves which floated past the burrow opening. The A. macellarius and N. acanthus communities together collected in their burrows an amount of seagrass leaf material corresponding to more than 50% of the leaf production in the meadows studied. The crustacean species studied might therefore fulfil an important function in the nutrient cycling of tropical meadows. In the burrow most of the collected material is shredded into pieces. The burrows of both species had special chambers which serve as a storage for seagrass leaf material. Neaxius acanthus incorporated most of the material into the burrow wall lining, which is made of small sediment particles and macerated seagrass leaves. Phosphate concentrations measured in N. acanthus burrows compared with pore-water and water-column concentrations suggests that a substantial amount of the seagrass material undergoes decomposition in the burrows. Oxygen levels measured in these water bodies are indicative for a possible exchange of water between the burrow and its surroundings, most likely supported by the shrimps irrigating their burrows. By collecting leaf material in their burrows, nutrients that are otherwise lost from the seagrass meadow associated with detached leaves and leaf fragments carried away in the water column, are maintained in the

  6. Food habits of the Arabian skink, Scincus hemprichii Wiegmann, 1837, (Sauria: Scincidae), in the Southwest Saudi Arabia.

    PubMed

    Paray, Bilal A; Al-Mfarij, Abdul Rahman; Al-Sadoon, Mohammed K

    2018-01-01

    Food and feeding habits of the Arabian skink, Scincus hemprichii were investigated in Jazan province, southwest of Saudi Arabia. S. hemprichii individuals fed during eleven months of the year. The mass of food in the stomachs indicated that a high degree of foraging success occurred during the warm spring while the lowest was during winter with January as an exception to feeding by the lizard. Analysis of the contents of 60 stomachs revealed that the diet of S. hemprichii in the study area consisted of arthropods, with two species of beetles of the family Dermestidae ( Dermestis vulpinus and Dermestis maculates ) and three type of dipteran larvae, accounting for 76% of the total volume of the food items. Specimens collected during January had empty stomachs.

  7. Gauge-theoretic invariants for topological insulators: a bridge between Berry, Wess-Zumino, and Fu-Kane-Mele

    NASA Astrophysics Data System (ADS)

    Monaco, Domenico; Tauber, Clément

    2017-07-01

    We establish a connection between two recently proposed approaches to the understanding of the geometric origin of the Fu-Kane-Mele invariant FKM\\in Z_2, arising in the context of two-dimensional time-reversal symmetric topological insulators. On the one hand, the Z_2 invariant can be formulated in terms of the Berry connection and the Berry curvature of the Bloch bundle of occupied states over the Brillouin torus. On the other, using techniques from the theory of bundle gerbes, it is possible to provide an expression for FKM containing the square root of the Wess-Zumino amplitude for a certain U( N)-valued field over the Brillouin torus. We link the two formulas by showing directly the equality between the above-mentioned Wess-Zumino amplitude and the Berry phase, as well as between their square roots. An essential tool of independent interest is an equivariant version of the adjoint Polyakov-Wiegmann formula for fields T^2 → U(N), of which we provide a proof employing only basic homotopy theory and circumventing the language of bundle gerbes.

  8. Reef fishes have higher parasite richness at unfished Palmyra Atoll compared to fished Kiritimati Island

    USGS Publications Warehouse

    Lafferty, Kevin D.; Shaw, Jenny C.; Kuris, Armand M.

    2008-01-01

    We compared parasite communities at two coral atolls in the Line Islands chain of the central Pacific (Kiritimati Island and Palmyra Atoll). Palmyra Atoll is relatively pristine while Kiritimati Island is heavily fished. At each island, we sampled five fish species for helminth and arthropod endoparasites: Chromis margaritifer, Plectroglyphidodon dickii,Paracirrhites arcatus, Acanthurus nigricans, and Lutjanus bohar. The surveys found monogeneans, digeneans, cestodes, nematodes, acanthocephalans, and copepods. Parasite richness was higher at Palmyra compared to Kiritimati for all five fish species. Fishes from Palmyra also tended to have more parasites species per host, higher parasite prevalence, and higher parasite abundance than did fishes from Kiritimati. The lower parasitism at Kiritimati may result from a simplified food web due to over fishing. Low biodiversity could impair parasite transmission by reducing the availability of hosts required by parasites with complex life cycles. Most notably, the lower abundances of larval shark tapeworms at Kiritimati presumably reflect the fact that fishing has greatly depleted sharks there in comparison to Palmyra.

  9. Hydrodynamic description of spin Calogero-Sutherland model

    NASA Astrophysics Data System (ADS)

    Abanov, Alexander; Kulkarni, Manas; Franchini, Fabio

    2009-03-01

    We study a non-linear collective field theory for an integrable spin-Calogero-Sutherland model. The hydrodynamic description of this SU(2) model in terms of charge density, charge velocity and spin currents is used to study non-perturbative solutions (solitons) and examine their correspondence with known quantum numbers of elementary excitations [1]. A conventional linear bosonization or harmonic approximation is not sufficient to describe, for example, the physics of spin-charge (non)separation. Therefore, we need this new collective bosonic field description that captures the effects of the band curvature. In the strong coupling limit [2] this model reduces to integrable SU(2) Haldane-Shastry model. We study a non-linear coupling of left and right spin currents which form a Kac-Moody algebra. Our quantum hydrodynamic description for the spin case is an extension for the one found in the spinless version in [3].[3pt] [1] Y. Kato,T. Yamamoto, and M. Arikawa, J. Phys. Soc. Jpn. 66, 1954-1961 (1997).[0pt] [2] A. Polychronakos, Phys Rev Lett. 70,2329-2331(1993).[0pt] [3] A.G.Abanov and P.B. Wiegmann, Phys Rev Lett 95, 076402(2005)

  10. Long-term exposure of several marine benthic animals to static magnetic fields.

    PubMed

    Bochert, R; Zettler, M L

    2004-10-01

    Electrical currents in underwater sea cables could induce magnetic fields. The sea cables lie on or within the sea bottom and this is the living area for many invertebrate and vertebrate species. North Sea prawn Crangon crangon (Crustacea, Decapoda), round crab Rhithropanopeus harrisii (Crustacea, Brachyura), glacial relict isopod Saduria entomon (Crustacea, Isopoda), blue mussel Mytilus edulis (Bivalvia), and young flounder Plathichthys flesus (Pisces) were exposed to a static magnetic field (MF) of 3.7 mT for several weeks. The results showed no differences in survival between experimental and control animals. Mussels M. edulis were kept under static magnetic field conditions for 3 months during their reproductive period in spring. The determination of gonad index and condition index revealed no significant differences to the control group. 2004 Wiley-Liss, Inc.

  11. Annotated checklist of the decapod crustaceans of the Gulf of Oman, northwestern Indian Ocean.

    PubMed

    Naderloo, Reza; Ebrahimnezhad, Saeed; Sari, Alireza

    2015-10-09

    The decapod crustaceans of the Gulf of Oman have been documented based on the published literature and new sampling along the Iranian coast between 2005 and 2015. A total of 121 species were collected along the Iranian coast, of which 43 are new records for the Gulf of Oman. The Decapoda of the Gulf is currently represented by 258 species belonging to five infraorders: Axiidea, Achelata, Anomura, Brachyura, and Caridea. Brachyura, with 176 species, are the best represented group, followed by Anomura and Caridea with 42 and 17 species, respectively. The least diverse groups are Achelata, with five species, and Axiidea, with three. On the basis of the available information, the northern (Iranian) coast with 189 species is more diverse than the southern (United Arab Emirates and Oman) coast with 134 species.

  12. Digital Rock Physics of hydrate-bearing sediments: Determination of effective elastic properties on the microscale

    NASA Astrophysics Data System (ADS)

    Sell, Kathleen; Saenger, Erik H.; Quintal, Beatriz; Enzmann, Frieder; Kersten, Michael

    2017-04-01

    the path to the digital rock physics of gas hydrate-bearing sediments - processing of in situ synchrotron-tomography data, Solid Earth, 7(4), 1243-1258, 2016. Andrä, H., Combaret, N., Dvorkin, J., Glatt, E., Han, J., Kabel, M., Keehm, Y., Krzikalla, F., Lee, M., Madonna, C., Marsh, M., Mukerji, T., Saenger, E. H., Sain, R., Saxena, N., Ricker, S., Wiegmann, A., and Zhan, X.: Digital rock physics benchmarks - Part II: Computing effective properties, Comput. Geosci., 50, 33-43, 2013a. Andrä, H., Combaret, N., Dvorkin, J., Glatt, E., Han, J., Kabel, M., Keehm, Y., Krzikalla, F., Lee, M., Madonna, C., Marsh, M., Mukerji, T., Saenger, E. H., Sain, R., Saxena, N., Ricker, S., Wiegmann, A., and Zhan, X.: Digital rock physics benchmarks - Part I: Imaging and segmentation, Comput. Geosci., 50, 25-32, 2013b.

  13. Fifty million years of herbivory on coral reefs: fossils, fish and functional innovations

    PubMed Central

    Bellwood, D. R.; Goatley, C. H. R.; Brandl, S. J.; Bellwood, O.

    2014-01-01

    The evolution of ecological processes on coral reefs was examined based on Eocene fossil fishes from Monte Bolca, Italy and extant species from the Great Barrier Reef, Australia. Using ecologically relevant morphological metrics, we investigated the evolution of herbivory in surgeonfishes (Acanthuridae) and rabbitfishes (Siganidae). Eocene and Recent surgeonfishes showed remarkable similarities, with grazers, browsers and even specialized, long-snouted forms having Eocene analogues. These long-snouted Eocene species were probably pair-forming, crevice-feeding forms like their Recent counterparts. Although Eocene surgeonfishes likely played a critical role as herbivores during the origins of modern coral reefs, they lacked the novel morphologies seen in modern Acanthurus and Siganus (including eyes positioned high above their low-set mouths). Today, these forms dominate coral reefs in both abundance and species richness and are associated with feeding on shallow, exposed algal turfs. The radiation of these new forms, and their expansion into new habitats in the Oligocene–Miocene, reflects the second phase in the development of fish herbivory on coral reefs that is closely associated with the exploitation of highly productive short algal turfs. PMID:24573852

  14. Fish larval recruitment to reefs is a thyroid hormone-mediated metamorphosis sensitive to the pesticide chlorpyrifos

    PubMed Central

    Lambert, Anne; François, Loïc; Barth, Paul; Gillet, Benjamin; Hughes, Sandrine; Piganeau, Gwenaël; Leulier, Francois; Viriot, Laurent

    2017-01-01

    Larval recruitment, the transition of pelagic larvae into reef-associated juveniles, is a critical step for the resilience of marine fish populations but its molecular control is unknown. Here, we investigate whether thyroid-hormones (TH) and their receptors (TR) coordinate the larval recruitment of the coral-reef-fish Acanthurus triostegus. We demonstrate an increase of TH-levels and TR-expressions in pelagic-larvae, followed by a decrease in recruiting juveniles. We generalize these observations in four other coral reef-fish species. Treatments with TH or TR-antagonist, as well as relocation to the open-ocean, disturb A. triostegus larvae transformation and grazing activity. Likewise, chlorpyrifos, a pesticide often encountered in coral-reefs, impairs A. triostegus TH-levels, transformation, and grazing activity, hence diminishing this herbivore’s ability to control the spread of reef-algae. Larval recruitment therefore corresponds to a TH-controlled metamorphosis, sensitive to endocrine disruption. This provides a framework to understand how larval recruitment, critical to reef-ecosystems maintenance, is altered by anthropogenic stressors. PMID:29083300

  15. Mercury (Hg) speciation in coral reef systems of remote Oceania: Implications for the artisanal fisheries of Tutuila, Samoa Islands.

    PubMed

    Morrison, R John; Peshut, Peter J; West, Ronald J; Lasorsa, Brenda K

    2015-07-15

    We investigated Hg in muscle tissue of fish species from three trophic levels on fringing reefs of Tutuila (14°S, 171°W), plus water, sediment and turf alga. Accumulation of total Hg in the herbivore Acanthurus lineatus (Acanthuridae, lined surgeonfish, (n=40)) was negligible at 1.05 (±0.04) ng g(-1) wet-weight, (∼65% occurring as methyl Hg). The mid-level carnivore Parupeneus spp. (Mullidae, goatfishes (n=10)) had total Hg 29.8 (±4.5) ng g(-1) wet-weight (∼99% as methyl Hg). Neither A. lineatus or Parupeneus spp. showed a propensity to accumulate Hg based on body size. Both groups were assigned a status of "un-restricted" for monthly consumption limits for non-carcinogenic health endpoints for methyl Hg. The top-level carnivore Sphyraena qenie (Sphyraenidae, blackfin barracuda, n=3) had muscle tissue residues of 105, 650 and 741 ng g(-1) wet-weight (100% methyl Hg, with increasing concentration with body mass, suggesting that S. qenie >15 kg would have a recommendation of "no consumption". Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Inventory of the tropical coral reef fishes in Wondama Bay regency, West Papua, Indonesia

    NASA Astrophysics Data System (ADS)

    Madiyani, K. D. P.; Triastuti, J.; Pursetyo, K. T.

    2018-04-01

    Teluk Wondama Regency is one of the areas in West Papua that is part of the Cendrawasih Bay National Park due to its potential of coral fishes. Until now, there is no thorough information that gives the potential diversities of coral fishes species can be found in the waters, and one of the attempts to find out is to carry out an inventory. Inventories were conducted from March to May 2016 in Rariei and Auri (Roon District), Numamuran (Duairi District), Nusrowi (Rumberpon District) and Waprak (Roswar District). The results of these inventories found 28 species of coral fishes in Rariei consisting of 8 genus (Balistapus, Synodus, Pentapodus, Thalassoma, Zebrasoma, Amblyglyphidodon, Chaetodon and Labroides) in Rariei, 11 genus (Abudefduf, Chaetodon, Amphiprion, Cheilinus, Dascyllus, Chromis, Parastromateus, Priacanthus, Epinephelus, Nemipterus and Lutjanus) in Namamuran, 11 genus in Nusrowi (Halichoeres, Pomacentrus, Dischistodus, Heniochus, Amblyglyphidodon, Arothron, Parupeneus, Lutjanus, Plectropomus, Epinephelus and Acanthurus), 4 genus in the waters of Waprak (Parupeneus, Pomacentrus, Chaetodon and Amblyglyphidodon) and 10 genus in Auri (Lutjanus, Pomacentrus, Amphiprion, Chaetodon, Chromis, Dascyllus, Zanclus, Halichoeres, Siganus and Amblyglyphidodon)

  17. Fifty million years of herbivory on coral reefs: fossils, fish and functional innovations.

    PubMed

    Bellwood, D R; Goatley, C H R; Brandl, S J; Bellwood, O

    2014-04-22

    The evolution of ecological processes on coral reefs was examined based on Eocene fossil fishes from Monte Bolca, Italy and extant species from the Great Barrier Reef, Australia. Using ecologically relevant morphological metrics, we investigated the evolution of herbivory in surgeonfishes (Acanthuridae) and rabbitfishes (Siganidae). Eocene and Recent surgeonfishes showed remarkable similarities, with grazers, browsers and even specialized, long-snouted forms having Eocene analogues. These long-snouted Eocene species were probably pair-forming, crevice-feeding forms like their Recent counterparts. Although Eocene surgeonfishes likely played a critical role as herbivores during the origins of modern coral reefs, they lacked the novel morphologies seen in modern Acanthurus and Siganus (including eyes positioned high above their low-set mouths). Today, these forms dominate coral reefs in both abundance and species richness and are associated with feeding on shallow, exposed algal turfs. The radiation of these new forms, and their expansion into new habitats in the Oligocene-Miocene, reflects the second phase in the development of fish herbivory on coral reefs that is closely associated with the exploitation of highly productive short algal turfs.

  18. Floating marine litter as a raft for drifting voyages for Planes minutus (Crustacea: Decapoda: Grapsidae) and Liocarcinus navigator (Crustacea: Decapoda: Polybiidae).

    PubMed

    Tutman, P; Kapiris, K; Kirinčić, M; Pallaoro, A

    2017-07-15

    The Columbus crab Planes minutus and Arch-fronted swimming crab Liocarcinus navigator, within their distribution ranges in the Mediterranean, were found rafted on plastic macro-litter floating on the open south Adriatic. While P. minutus was recorded from inanimate flotsam outside of the Mediterranean, L. navigator is herein reported for the first time on floating marine litter. The role of floating litter as habitat or as a dispersal agent for marine invertebrates has received quite attention however, records of decapod crabs drifting on litter has been relatively sparse. Our results suggests that vast quantities of floating debris, comprised primarily of non-biodegradable plastic polymers, probably will augment natural floating substrates in the marine environment, potentially facilitating the spread of invasive species. The dispersion of rafting crabs through floating debris should be investigated given the high potential ecological risk of invasion by exotic species due to the increase in waste production (ecological risk assessment). Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Olfactory projection neuron pathways in two species of marine Isopoda (Peracarida, Malacostraca, Crustacea).

    PubMed

    Stemme, Torben; Eickhoff, René; Bicker, Gerd

    2014-08-01

    The neuroanatomy of the olfactory pathway has been intensely studied in many representatives of Malacostraca. Nevertheless, the knowledge about bilateral olfactory integration pathways is mainly based on Decapoda. Here, we investigated the olfactory projection neuron pathway of two marine isopod species, Saduria entomon and Idotea emarginata, by lipophilic dye injections into the olfactory neuropil. We show that both arms of the olfactory globular tract form a chiasm in the center of the brain, as known from several other crustaceans. Furthermore, the olfactory projection neurons innervate both the medulla terminalis and the hemiellipsoid body of the ipsi- and the contralateral hemisphere. Both protocerebral neuropils are innervated to a comparable extent. This is reminiscent of the situation in the basal decapod taxon Dendrobranchiata. Thus, we propose that an innervation by the olfactory globular tract of both the medulla terminalis and the hemiellipsoid body is characteristic of the decapod ground pattern, but also of the ground pattern of Caridoida. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Decreased retention of olfactory predator recognition in juvenile surgeon fish exposed to pesticide.

    PubMed

    Bertucci, Frédéric; Jacob, Hugo; Mignucci, Alexandre; Gache, Camille; Roux, Natacha; Besson, Marc; Berthe, Cécile; Metian, Marc; Lecchini, David

    2018-06-04

    Dory, the animated surgeonfish created by the Pixar Animation studios, famously suffered from short-term memory loss leading to many adventures. In reality, many fishes have excellent cognitive abilities and are able to learn and retain important information such as the identity of predators. However, if and how cognition can be affected by anthropogenically altered oceanic conditions is poorly understood. Here, we examine the effect of a widely used pesticide, chlorpyrifos, on the retention of acquired predator recognition in post-larval stage of the surgeonfish Acanthurus triostegus. Through associative learning, post-larvae of A. triostegus were first observed to forage significantly less in the presence of conspecific alarm cues and alarm cues associated to a predator's odor. The retention of this anti-predator behavior was estimated to last between 2 and 5 days in the absence of pesticide. However, environmentally-relevant concentrations of chlorpyrifos (1 μg.L -1 ) induced the loss of this acquired predator recognition. This reduced ability to recognize learned predators is discussed as it may lead to more vulnerable fish communities in coastal areas subjected to organophosphate pesticide pollution. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. DNA barcoding reveals new insights into the diversity of Antarctic species of Orchomene sensu lato (Crustacea: Amphipoda: Lysianassoidea)

    NASA Astrophysics Data System (ADS)

    Havermans, C.; Nagy, Z. T.; Sonet, G.; De Broyer, C.; Martin, P.

    2011-03-01

    Recent molecular analyses revealed that several so-called "circum-Antarctic" benthic crustacean species appeared to be complexes of cryptic species with restricted distributions. In this study we used a DNA barcoding approach based on mitochondrial cytochrome oxidase I gene sequences in order to detect possible cryptic diversity and to test the circumpolarity of some lysianassoid species. The orchomenid genus complex consists of the genera Abyssorchomene, Falklandia, Orchomenella, Orchomenyx and Pseudorchomene. Species of this genus complex are found throughout the Southern Ocean and show a high species richness and level of endemism. In the majority of the studied species, a genetic homogeneity was found even among specimens from remote sampling sites, which indicates a possible circum-Antarctic and eurybathic distribution. In four investigated species ( Orchomenella ( Orchomenopsis) acanthurus, Orchomenella ( Orchomenopsis) cavimanus, Orchomenella ( Orchomenella) franklini and Orchomenella ( Orchomenella) pinguides), genetically divergent lineages and possible cryptic taxa were revealed. After a detailed morphological analysis, O. ( O.) pinguides appeared to be composed of two distinct species, formerly synonymized under O. ( O.) pinguides. The different genetic patterns observed in these orchomenid species might be explained by the evolutionary histories undergone by these species and by their different dispersal and gene flow capacities.

  2. Effects of three Caribbean cleaner shrimps on ectoparasitic monogeneans in a semi-natural environment

    NASA Astrophysics Data System (ADS)

    McCammon, A.; Sikkel, P. C.; Nemeth, D.

    2010-06-01

    Most research on cleaning symbioses on coral reefs has focused on fish clients being cleaned by smaller fishes. While many shrimps and other crustaceans are reported as cleaners, whether they remove parasites from fish hosts and can effectively regulate populations of ectoparasites is unclear. The effects of Pederson shrimp ( Periclimenes pedersoni) , spotted shrimp ( P. yucatanicus), and banded coral shrimp ( Stenopus hispidus), on the parasitic monogenean Neobenedenia melleni on a host reef fish, blue tang ( Acanthurus coeruleus), were investigated. The abundance and size of N. melleni from fish with and without access to shrimps in a semi-natural macrocosm was quantified. P. pedersoni had a strong effect on both the abundance and size of parasites. In contrast, P. yucatanicus and S. hispidus had no effect on the abundance of parasites but had a small yet statistically significant effect on average size. These data suggest that P. pedersoni can play a significant role in the biological regulation of at least some ectoparasites on Caribbean reef fishes, but further suggest that some other shrimps regarded as “cleaners” may have little or no effectiveness at removing parasites and underscore the need for further verification before this term is applied.

  3. 40Ar/ 39Ar age and oxygen isotope temperature of the Centinela Formation, southwestern Argentina: An Eocene age for crustacean-rich "Patagonian" beds

    NASA Astrophysics Data System (ADS)

    Casadío, Silvio; Feldmann, Rodney M.; Foland, Kenneth A.

    2000-05-01

    The presence of a prominent volcanic ash enclosed within sediments of the Centinela Formation, southwestern Argentina, permits establishment of an 40Ar/ 39Ar age of approximately 46 Ma for these rocks. Oxygen isotopic analysis of shell material from the oyster Crassostrea? hatcheriOrtmann, 1897, suggests seasonal fluctuation of temperature from about 15°C to about 21°C. In concordance with this, a diverse crustacean fauna, including nine families within the order Decapoda and one within Isopoda, bears strong affinities with temperate and subtropical faunas of the Atlantic Ocean basin and documents the southernmost extension of low latitude oceanographic influence on this region during the Paleogene. Establishment of an Eocene age for the rocks in the Centinela Formation provides the first definitive documentation of rocks of that age in the region of Calafate, permits correlation of these rocks with Eocene strata southward to the vicinity of Río Turbio, and suggests that these rocks, assigned to the Patagonian sequence, may be substantially older than those in eastern Argentina.

  4. Effects of full-stream carbon filtration on the development of head and lateral line erosion syndrome (HLLES) in ocean surgeon.

    PubMed

    Stamper, M Andrew; Kittell, Michele M; Patel, Erin E; Corwin, Allison L

    2011-09-01

    Head and lateral line erosion syndrome (HLLES) is a common but very poorly understood disease of marine aquarium fish. One suspected etiology is the use of granulated activated carbon (GAC) to filter the water. Seventy-two ocean surgeons Acanthurus bahianus were distributed among three carbon-negative control systems and three GAC-treated systems such that each tank contained approximately the same total body mass. Each replicate system was made up of two 250-L circular tanks with a common filtration system (6 fish per tank, 12 fish per replicate system). The GAC-treated tanks were exposed to full-stream, extruded coconut shell activated carbon, which produced a mean total organic carbon content of 0.4 mg/L. The results of this study indicate that extruded coconut shell activated carbon filtering at full-stream rates can cause HLLES-type lesions in ocean surgeons. The HLLES developed exponentially over 15 d, beginning in the chin region. This was followed by pitting in the cheek region, which expanded until erosions coalesced. Once the carbon was discontinued, the processes reversed in a mean time of 49 d. As the lesions healed, they reverted from the coalesced to the pitted stage and then darkened before returning to normal.

  5. Crayfishes (Decapoda : Cambaridae) of Oklahoma: identification, distributions, and natural history.

    PubMed

    Morehouse, Reid L; Tobler, Michael

    2013-01-01

    We furnish an updated crayfish species list for the state of Oklahoma (United States of America), including an updated and illustrated dichotomous key. In addition, we include species accounts that summarize general characteristics, life coloration, similar species, distribution and habitat, life history, and syntopic species. Current and potential distributions were analyzed using ecological niche models to provide a critical resource for the identification of areas with conservation priorities and potential susceptibility to invasive species. Currently, Oklahoma harbors 30 species of crayfish, two of which were recently discovered. Eastern Oklahoma has the highest species diversity, as this area represents the western distribution extent for several species. The work herein provides baseline data for future work on crayfish biology and conservation in Oklahoma and surrounding states.

  6. Genome Sequences of Marine Shrimp Exopalaemon carinicauda Holthuis Provide Insights into Genome Size Evolution of Caridea.

    PubMed

    Yuan, Jianbo; Gao, Yi; Zhang, Xiaojun; Wei, Jiankai; Liu, Chengzhang; Li, Fuhua; Xiang, Jianhai

    2017-07-05

    Crustacea, particularly Decapoda, contains many economically important species, such as shrimps and crabs. Crustaceans exhibit enormous (nearly 500-fold) variability in genome size. However, limited genome resources are available for investigating these species. Exopalaemon carinicauda Holthuis, an economical caridean shrimp, is a potential ideal experimental animal for research on crustaceans. In this study, we performed low-coverage sequencing and de novo assembly of the E. carinicauda genome. The assembly covers more than 95% of coding regions. E. carinicauda possesses a large complex genome (5.73 Gb), with size twice higher than those of many decapod shrimps. As such, comparative genomic analyses were implied to investigate factors affecting genome size evolution of decapods. However, clues associated with genome duplication were not identified, and few horizontally transferred sequences were detected. Ultimately, the burst of transposable elements, especially retrotransposons, was determined as the major factor influencing genome expansion. A total of 2 Gb repeats were identified, and RTE-BovB, Jockey, Gypsy, and DIRS were the four major retrotransposons that significantly expanded. Both recent (Jockey and Gypsy) and ancestral (DIRS) originated retrotransposons responsible for the genome evolution. The E. carinicauda genome also exhibited potential for the genomic and experimental research of shrimps.

  7. Evaluating the impact of seismic prospecting on artisanal shrimp fisheries

    NASA Astrophysics Data System (ADS)

    Andriguetto-Filho, José M.; Ostrensky, Antonio; Pie, Marcio R.; Silva, Ubiratã A.; Boeger, Walter A.

    2005-09-01

    The constant need to discover new hydrocarbon deposits is causing the use of air-guns to become a very widespread method of seismic prospecting. However, there is still disagreement regarding their impact on the marine environment. This uncertainty is particularly severe in the case of shellfish, which account for a substantial share of commercial fisheries and seafood trade in many parts of the world. In this paper we report on the first study to explicitly assess the impact of seismic prospecting on shrimp resources. We measured bottom trawl yields of a nonselective commercial shrimp fishery comprising the Southern white shrimp, Litopenaeus schmitti, the Southern brown shrimp, Farfantepenaeus subtilis, and the Atlantic Seabob, Xyphopenaeus kroyeri (Decapoda: Penaeidae), before and after the use of an array of four synchronized air-guns, each with 635 in 3 of total capacity, 2.000 psi, and peak pressure of 196 dB (re 1 μPa at 1 m). Our results did not detect significant deleterious impact of seismic prospecting on the studied species, suggesting that shrimp stocks are resilient to the disturbance by air-guns under our experimental conditions.

  8. Fine structure and ecdysis of mandibular sensilla associated with the lacinia mobilis in Neomysis integer (Leach, 1814) (Crustacea, Malacostraca, Peracarida).

    PubMed

    Geiselbrecht, Hannes; Melzer, Roland R

    2014-05-01

    The external and internal structures of adult Neomysis integer mandibles were studied using light and electron microscopy with special reference to the lacinia mobilis, a highly specialized appendage on the gnathal edge of many crustaceans. The right and left lacinia mobilis are equipped with ciliary primary sensory cells revealing that both laciniae are also mechanosensory organs in addition to their mechanical function during mastication. A detailed character analyses indicated that the right lacinia is probably a highly derived sensory seta, whereas two alternative interpretations are considered for the left lacinia; it could be a sensillar appendage equipped with two mechanosensory units, or it could be a movable appendage of the incisor process containing two sensilla deprived of external appendages. The ecdysis of the lacinia mobilis corresponds very well to type I sensillar ecdysis, suggesting classification as a sensillar appendage. These features support a possible homology of the right lacinia mobilis in Peracarida and Decapoda, tracing them to an origin as a member of the setal row. Whether the left lacinia mobilis is a sensillum or an appendage with sensilla cannot be resolved presently. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Looking back on a decade of barcoding crustaceans

    PubMed Central

    Raupach, Michael J.; Radulovici, Adriana E.

    2015-01-01

    Abstract Species identification represents a pivotal component for large-scale biodiversity studies and conservation planning but represents a challenge for many taxa when using morphological traits only. Consequently, alternative identification methods based on molecular markers have been proposed. In this context, DNA barcoding has become a popular and accepted method for the identification of unknown animals across all life stages by comparison to a reference library. In this review we examine the progress of barcoding studies for the Crustacea using the Web of Science data base from 2003 to 2014. All references were classified in terms of taxonomy covered, subject area (identification/library, genetic variability, species descriptions, phylogenetics, methods, pseudogenes/numts), habitat, geographical area, authors, journals, citations, and the use of the Barcode of Life Data Systems (BOLD). Our analysis revealed a total number of 164 barcoding studies for crustaceans with a preference for malacostracan crustaceans, in particular Decapoda, and for building reference libraries in order to identify organisms. So far, BOLD did not establish itself as a popular informatics platform among carcinologists although it offers many advantages for standardized data storage, analyses and publication. PMID:26798245

  10. Ontogenetic scaling of the olfactory antennae and flicking behavior of the shore crab, Hemigrapsus oregonensis.

    PubMed

    Waldrop, Lindsay D

    2013-07-01

    Malacostracan crustaceans such as crabs flick antennae with arrays of olfactory sensilla called aesthetascs through the water to sense odors. Flicking by crabs consists of a quick downstroke, in which aesthetascs are deflected laterally (splayed), and a slower, reversed return stroke, in which aesthetascs clump together. This motion causes water to be flushed within and then held in between aesthetascs to deliver odor molecules to olfactory receptors. Although this odor sampling method relies on a narrow range of speeds, sizes, and specific arrangements of aesthetascs, most crabs dramatically change these during ontogeny. In this study, the morphometrics of the aesthetascs, array, and antennae and the flicking kinematics of the Oregon shore crab, Hemigrapsus oregonensis (Decapoda: Brachyura), are examined to determine their scaling relationships during ontogeny. The morphometrics of the array and antennae increase more slowly than would be predicted by isometry. Juvenile crabs' aesthetascs splay relatively further apart than adults, likely due to changing material properties of aesthetasc cuticle during growth. These results suggest that disproportionate growth and altered aesthetasc splay during flicking will mediate the size changes due to growth that would otherwise lead to a loss of function.

  11. On the brain of a crustacean: a morphological analysis of CaMKII expression and its relation to sensory and motor pathways.

    PubMed

    Ammar, Dib; Nazari, Evelise M; Müller, Yara M R; Allodi, Silvana

    2013-01-01

    Calcium/calmodulin kinase II (CaMKII) is a Ca(2+)-activated enzyme that is abundant in vertebrate and invertebrate brains. However, its characterization is poorly addressed in the nervous system of crustaceans, and, to our knowledge, no studies have determined the microanatomical location of CaMKII in a crustacean species. In this study, we found labeling of CaMKII in the eyestalk and brain of the prawn Macrobrachium acanthurus, by means of immunohistochemistry and Western blotting. Antibodies against neuron (ß tubulin III), glutamate receptor (GluA1), and FMRFamide were used in order to further characterize the CaMKII-labeled cells in the brain. In the eyestalk, strong labeling with CaMKII was observed in the photoreceptors. These cells, especially in the rhabdom, were also reactive to anti-ß tubulin III, whereas the pigment cells were labeled with anti-CaMKII. GluA1 co-located with CaMKII in the photoreceptors. Also, CaMKII appeared in the same sites as FMRFamide in the deutocerebrum, including the olfactory lobe, and in the tritocerebrum, specifically in the antennular neuropil, indicating that the synaptic areas in these regions may be related to sensory-motor processing. In the brain, the identification of cells and regions that express CaMKII contributes to the understanding of the processing of neural connections and the modulating role of CaMKII in decapod crustaceans.

  12. Reef Fish Community Biomass and Trophic Structure Changes across Shallow to Upper-Mesophotic Reefs in the Mesoamerican Barrier Reef, Caribbean

    PubMed Central

    Gress, Erika; Wright, Georgina; Exton, Dan A.; Rogers, Alex D.

    2016-01-01

    Mesophotic coral ecosystems (MCEs; reefs 30-150m depth) are of increased research interest because of their potential role as depth refuges from many shallow reef threats. Yet few studies have identified patterns in fish species composition and trophic group structure between MCEs and their shallow counterparts. Here we explore reef fish species and biomass distributions across shallow to upper-MCE Caribbean reef gradients (5-40m) around Utila, Honduras, using a diver-operated stereo-video system. Broadly, we found reef fish species richness, abundance and biomass declining with depth. At the trophic group level we identified declines in herbivores (both total and relative community biomass) with depth, mostly driven by declines in parrotfish (Scaridae). Piscivores increased as a proportion of the community with increased depth while, in contrast to previous studies, we found no change in relative planktivorous reef fish biomass across the depth gradient. In addition, we also found evidence of ontogenetic migrations in the blue tang (Acanthurus coeruleus), striped parrotfish (Scarus iserti), blue chromis (Chromis cyanea), creole wrasse (Clepticus parrae), bluehead wrasse (Thalassoma bifasciatum) and yellowtail snapper (Ocyurus chrysurus), with a higher proportion of larger individuals at mesophotic and near-mesophotic depths than on shallow reefs. Our results highlight the importance of using biomass measures when considering fish community changes across depth gradients, with biomass generating different results to simple abundance counts. PMID:27332811

  13. Decapoda from Antipatharia, Gorgonaria and Bivalvia at the Cape Verde Islands

    NASA Astrophysics Data System (ADS)

    Wirtz, Peter; d'Udekem-d'Acoz, Cédric

    2001-07-01

    The shrimps Balssia gasti, Palaemonella atlantica, Periclimenes platalea, Periclimenes wirtzi, Pontonia manningi, Pontonia pinnophylax, Pontonia sp. nov., Pseudocoutierea wirtzi and the crabs Galathea intermedia and Micropisa ovata were collected from Antipatharia, Gorgonaria and Bivalvia at São Tiago Island, Republic of Cape Verde. Most of the associations between decapods and invertebrate hosts are reported here for the first time. This is also the first record of B. gasti and of P. wirtzi for the Cape Verde Islands. We briefly review the literature on littoral decapod crustaceans of the Cape Verde Islands.

  14. Phylogeny and Evolutionary Patterns in the Dwarf Crayfish Subfamily (Decapoda: Cambarellinae)

    PubMed Central

    Pedraza-Lara, Carlos; Doadrio, Ignacio; Breinholt, Jesse W.; Crandall, Keith A.

    2012-01-01

    The Dwarf crayfish or Cambarellinae, is a morphologically singular subfamily of decapod crustaceans that contains only one genus, Cambarellus. Its intriguing distribution, along the river basins of the Gulf Coast of United States (Gulf Group) and into Central México (Mexican Group), has until now lacked of satisfactory explanation. This study provides a comprehensive sampling of most of the extant species of Cambarellus and sheds light on its evolutionary history, systematics and biogeography. We tested the impact of Gulf Group versus Mexican Group geography on rates of cladogenesis using a maximum likelihood framework, testing different models of birth/extinction of lineages. We propose a comprehensive phylogenetic hypothesis for the subfamily based on mitochondrial and nuclear loci (3,833 bp) using Bayesian and Maximum Likelihood methods. The phylogenetic structure found two phylogenetic groups associated to the two main geographic components (Gulf Group and Mexican Group) and is partially consistent with the historical structure of river basins. The previous hypothesis, which divided the genus into three subgenera based on genitalia morphology was only partially supported (P = 0.047), resulting in a paraphyletic subgenus Pandicambarus. We found at least two cases in which phylogenetic structure failed to recover monophyly of recognized species while detecting several cases of cryptic diversity, corresponding to lineages not assigned to any described species. Cladogenetic patterns in the entire subfamily are better explained by an allopatric model of speciation. Diversification analyses showed similar cladogenesis patterns between both groups and did not significantly differ from the constant rate models. While cladogenesis in the Gulf Group is coincident in time with changes in the sea levels, in the Mexican Group, cladogenesis is congruent with the formation of the Trans-Mexican Volcanic Belt. Our results show how similar allopatric divergence in freshwater organisms can be promoted through diverse vicariant factors. PMID:23155379

  15. The male reproductive system of Hippolyte inermis Leach 1815 (Decapoda, Caridea)

    NASA Astrophysics Data System (ADS)

    Cobos, Vanesa; Díaz, Vanessa; Raso, Jose Enrique García; Manjón-Cabeza, M. E.

    2011-03-01

    The present work completes a series of studies on the biology of the shrimp Hippolyte inermis Leach 1815, where we suggested the species to be gonochoristic. The morphology of the male reproductive system (testes, vasa deferentia, gonopores) and the different stages of male germ cell development are described for the first time in the genus Hippolyte, using TEM, SEM, and histological methods. All males from 1.70 to 3.42 mm in carapace length had active testes and well-developed vasa deferentia. No case of sex reversal could be found.

  16. Brain architecture of the Pacific White Shrimp Penaeus vannamei Boone, 1931 (Malacostraca, Dendrobranchiata): correspondence of brain structure and sensory input?

    PubMed

    Meth, Rebecca; Wittfoth, Christin; Harzsch, Steffen

    2017-08-01

    Penaeus vannamei (Dendrobranchiata, Decapoda) is best known as the "Pacific White Shrimp" and is currently the most important crustacean in commercial aquaculture worldwide. Although the neuroanatomy of crustaceans has been well examined in representatives of reptant decapods ("ground-dwelling decapods"), there are only a few studies focusing on shrimps and prawns. In order to obtain insights into the architecture of the brain of P. vannamei, we use neuroanatomical methods including X-ray micro-computed tomography, 3D reconstruction and immunohistochemical staining combined with confocal laser-scanning microscopy and serial sectioning. The brain of P. vannamei exhibits all the prominent neuropils and tracts that characterize the ground pattern of decapod crustaceans. However, the size proportion of some neuropils is salient. The large lateral protocerebrum that comprises the visual neuropils as well as the hemiellipsoid body and medulla terminalis is remarkable. This observation corresponds with the large size of the compound eyes of these animals. In contrast, the remaining median part of the brain is relatively small. It is dominated by the paired antenna 2 neuropils, while the deutocerebral chemosensory lobes play a minor role. Our findings suggest that visual input from the compound eyes and mechanosensory input from the second pair of antennae are major sensory modalities, which this brain processes.

  17. Facultative parasitism by the bivalve Kurtiella pedroana in the sand crab Emerita analoga

    USGS Publications Warehouse

    Bhaduri, Ritin; Valentich-Scott, Paul; Hilgers, Mark; Singh, Rajvir; Hickman, Mikaila; Lafferty, Kevin D.

    2017-01-01

    It is rare that an organism capable of independent or commensalistic existence can also become endoparasitic on a host. In this study, we documented a potential step toward parasitism in the commensal clam Kurtiella pedroana (Bivalvia: Galeommatoidea). Galeommatoideans are known commensals of various invertebrates, including crustaceans. Emerita analoga (Decapoda: Hippidae) is an abundant intertidal decapod inhabiting sandy beaches of the Pacific coast of North and South America. Crabs collected from Monterey Bay, California, were measured and examined externally and internally for associated molluscs. Out of the 520 crabs, 37 large female individuals harbored 49 bivalves (prevalence of 7.11% and mean intensity of 1.3). Forty-one ectocommensal clams were either inside the crab's branchial chambers or on their lateroventral surfaces, and were attached by byssal threads. Our key finding was eight clams that lacked byssal threads and were living in the hemocoel. These internal clams were significantly smaller than the ectocommensals. Because these internal clams lacked access to their normal food, we hypothesize they might have fed on their host's hemolymph as would a parasite. This clam species likely can't reproduce inside its host, implying that endoparasitism is a dead-end state for K. pedroana. Facultative parasitism in a free-living or an ectocommensal is uncommon and suggests a pathway to parasitism.

  18. Crystallization and preliminary X-ray diffraction studies of trypsin-like proteases from the gastric fluid of the marine crab Cancer pagurus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hehemann, Jan-Hendrik; Redecke, Lars; Perbandt, Markus

    2007-03-01

    Two trypsins from the gastric fluid of the marine crab C. pagurus were purified and crystallized and X-ray data were collected to 0.97 and 3.2 Å resolution. The digestive fluid of the marine crab Cancer pagurus (Decapoda, Brachyura) contains highly stable proteases which display enhanced activity in aqueous mixtures of organic solvents. Three trypsins were isolated from the gastric fluid and two of them, C.p.TryII and C.p.TryIII, were purified to homogeneity by anion-exchange chromatography and crystallized by hanging-drop vapour diffusion. Diffraction data were collected at a synchrotron to 0.97 and 3.2 Å resolution, respectively. The crystal of C.p.TryII belongs tomore » the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 52.06, b = 62.00, c = 71.66 Å. Based on the Matthews coefficient, one protein molecule per asymmetric unit is suggested. In contrast, crystals of C.p.TryIII, which belong to the cubic space group P2{sub 1}3 with unit-cell parameters a = b = c = 215.4 Å, are assumed to contain 12 molecules per asymmetric unit.« less

  19. Elucidating the trophodynamics of four coral reef fishes of the Solomon Islands using δ15N and δ13C

    NASA Astrophysics Data System (ADS)

    Greenwood, N. D. W.; Sweeting, C. J.; Polunin, N. V. C.

    2010-09-01

    Size-related diet shifts are important characteristics of fish trophodynamics. Here, body size-related changes in muscle δ15N and δ13C of four coral reef fishes, Acanthurus nigrofuscus (herbivore), Chaetodon lunulatus (corallivore) , Chromis xanthura (planktivore) and Plectropomus leopardus (piscivore) were investigated at two locations in the Solomon Islands. All four species occupied distinct isotopic niches and the concurrent δ13C' values of C. xanthura and P. leopardus suggested a common planktonic production source. Size-related shifts in δ15N, and thus trophic level, were observed in C. xanthura, C. lunulatus and P. leopardus, and these trends varied between location, indicating spatial differences in trophic ecology. A literature review of tropical fishes revealed that positive δ15N-size trends are common while negative δ15N-size trends are rare. Size-δ15N trends fall into approximately equal groups representing size-based feeding within a food chain, and that associated with a basal resource shift and occurs in conjunction with changes in production source, indicated by δ13C. The review also revealed large scale differences in isotope-size trends and this, combined with small scale location differences noted earlier, highlights a high degree of plasticity in the reef fishes studied. This suggests that trophic size analysis of reef fishes would provide a productive avenue to identify species potentially vulnerable to reef impacts as a result of constrained trophic behaviour.

  20. Gigantism in a bacterium, Epulopiscium fishelsoni, correlates with complex patterns in arrangement, quantity, and segregation of DNA.

    PubMed

    Bresler, V; Montgomery, W L; Fishelson, L; Pollak, P E

    1998-11-01

    Epulopiscium fishelsoni, gut symbiont of the brown surgeonfish (Acanthurus nigrofuscus) in the Red Sea, attains a larger size than any other eubacterium, varies 10- to 20-fold in length (and >2, 000-fold in volume), and undergoes a complex daily life cycle. In early morning, nucleoids contain highly condensed DNA in elongate, chromosome-like structures which are physically separated from the general cytoplasm. Cell division involves production of two (rarely three) nucleoids within a cell, deposition of cell walls around expanded nucleoids, and emergence of daughter cells from the parent cell. Fluorescence measurements of DNA, RNA, and other cell components indicate the following. DNA quantity is proportional to cell volume over cell lengths of approximately 30 micrometers to >500 micrometers. For cells of a given size, nucleoids of cells with two nucleoids (binucleoid) contain approximately equal amounts of DNA. And each nucleoid of a binucleoid cell contains one-half the DNA of the single nucleoid in a uninucleoid cell of the same size. The life cycle involves approximately equal subdivision of DNA among daughter cells, formation of apical caps of condensed DNA from previously decondensed and diffusely distributed DNA, and "pinching" of DNA near the middle of the cell in the absence of new wall formation. Mechanisms underlying these patterns remain unclear, but formation of daughter nucleoids and cells occurs both during diurnal periods of host feeding and bacterial cell growth and during nocturnal periods of host inactivity when mean bacterial cell size declines.

  1. Zinc uptake and regulation by the sublittoral prawn Pandalus montagui (Crustacea: Decapoda)

    NASA Astrophysics Data System (ADS)

    Nugegoda, D.; Rainbow, P. S.

    1988-06-01

    The sublittoral decapod crustacean Pandalus montagui Leach in artificial seawater at 10°C regulates the total body zinc concentration to a constant level in dissolved zinc concentrations up to ca. 22 μg Zn l -1, beyond which there is net accumulation of body zinc. This threshold of zinc regulation breakdown is lower than that in the littoral decapods Palaemon elegans (ca. 93 μg Zn l -1) and Palaemonetes varians (ca. 190 μg Zn l -1) under the same physico-chemical conditions. Correspondingly, zinc uptake rates of the three species of decapods decrease in the order P. montagui > P. elegans > P. varians. It is concluded that regulation of total body zinc concentration is more efficient in decapods adapted to the fluctuating environments of littoral habitats, possibly as a result of changes in permeability of uptake surfaces in combination with improved zinc excretion systems. The moult cycle is important in determining the ability of an individual prawn to regulate zinc. Body zinc in Pandalus montagui consists of at least two pools of zinc exchanging at different rates which the environment. Zinc and copper are not evenly distributed in the tissues of P. montagui.

  2. A comprehensive and integrative reconstruction of evolutionary history for Anomura (Crustacea: Decapoda)

    PubMed Central

    2013-01-01

    Background The infraorder Anomura has long captivated the attention of evolutionary biologists due to its impressive morphological diversity and ecological adaptations. To date, 2500 extant species have been described but phylogenetic relationships at high taxonomic levels remain unresolved. Here, we reconstruct the evolutionary history—phylogeny, divergence times, character evolution and diversification—of this speciose clade. For this purpose, we sequenced two mitochondrial (16S and 12S) and three nuclear (H3, 18S and 28S) markers for 19 of the 20 extant families, using traditional Sanger and next-generation 454 sequencing methods. Molecular data were combined with 156 morphological characters in order to estimate the largest anomuran phylogeny to date. The anomuran fossil record allowed us to incorporate 31 fossils for divergence time analyses. Results Our best phylogenetic hypothesis (morphological + molecular data) supports most anomuran superfamilies and families as monophyletic. However, three families and eleven genera are recovered as para- and polyphyletic. Divergence time analysis dates the origin of Anomura to the Late Permian ~259 (224–296) MYA with many of the present day families radiating during the Jurassic and Early Cretaceous. Ancestral state reconstruction suggests that carcinization occurred independently 3 times within the group. The invasion of freshwater and terrestrial environments both occurred between the Late Cretaceous and Tertiary. Diversification analyses found the speciation rate to be low across Anomura, and we identify 2 major changes in the tempo of diversification; the most significant at the base of a clade that includes the squat-lobster family Chirostylidae. Conclusions Our findings are compared against current classifications and previous hypotheses of anomuran relationships. Many families and genera appear to be poly- or paraphyletic suggesting a need for further taxonomic revisions at these levels. A divergence time analysis provides key insights into the origins of major lineages and events and the timing of morphological (body form) and ecological (habitat) transitions. Living anomuran biodiversity is the product of 2 major changes in the tempo of diversification; our initial insights suggest that the acquisition of a crab-like form did not act as a key innovation. PMID:23786343

  3. Use of intertidal areas by shrimps (Decapoda) in a Brazilian Amazon estuary.

    PubMed

    Sampaio, Hebert A; Martinelli-Lemos, Jussara M

    2014-03-01

    The present work investigated the occupation and the correlation of the shrimp abundance in relation to environmental variables in different habitats (mangroves, salt marshes and rocky outcrops) in an Amazon estuary. The collections were made in August and November 2009, at low syzygy tide on Areuá Beach, situated in the Extractive Reserve of Mãe Grande de Curuçá, Pará, Brazil totaling 20 pools. In each environment, we recorded the physical-chemical factors (pH, salinity, and temperature) and measured the area (m2) and volume (m3) of every pool through bathymetry. The average pH, salinity, temperature, area and volume of tide pools were 8.75 (± 0.8 standard deviation), 35.45 (± 3), 29.49 °C (± 2.32), 27.41 m2 (± 41.18), and 5.19 m3 (± 8.01), respectively. We caught a total of 4,871 shrimps, distributed in three families and four species: Farfantepenaeus subtilis (98.36%) (marine) followed by Alpheus pontederiae (0.76%) (estuarine), Macrobrachium surinamicum (0.45%) and Macrobrachium amazonicum (0.43%) predominantly freshwater. The species F. subtilis and A. pontederiae occurred in the three habitats, whereas M. surinamicum occurred in salt marsh and rocky outcrop and M. amazonicum only in marisma. Temperature and pH were the most important environmental descriptors that significantly affected the density and biomass of shrimps.

  4. Preliminary observations on the mandibles of palaemonoid shrimp (Crustacea: Decapoda: Caridea: Palaemonoidea)

    PubMed Central

    De Grave, Sammy; Johnson, Magnus L.

    2015-01-01

    The mandibles of caridean shrimps have been widely studied in the taxonomy and functional biology of the group. Within the Palaemonoidea the mandibles reach a high level of structural diversity reflecting the diverse lifestyles within the superfamily. However, the majority of studies have been restricted to light microscopy, with the ultrastructure at finer levels poorly known. This study investigates the mandible of nine species belonging to six of the recognised families of the Palaemonoidea using SEM and analyses the results in a phylogenetic and dietary framework. The results of the study indicate that little phylogenetic information is conveyed by the structure of the mandible, but that its form is influenced by primary food sources of each species. With the exception of Anchistioides antiguensis, all species examined possessed cuticular structures at the distal end of the pars molaris (molar process). Five types of cuticular structures are recognised herein, each with a unique form, but variable in number, placement and arrangement. Each type is presumed to have a different function which is likewise related to diet. PMID:25825676

  5. Suspension feeding in adult Nephrops norvegicus (L.) and Homarus gammarus (L.) (decapoda)

    NASA Astrophysics Data System (ADS)

    Loo, Lars-Ove; Pihl Baden, Susanne; Ulmestrand, Mats

    Suspension feeding in adults of the Norway lobster Nephrops norvegicus (40-74 g) and the European lobster Homarus gammarus (280-350 g) was tested in experiments offering planktonic food items of different sizes from 200 to 600 μm and measuring the clearing capacity. Both lobster species were found to effectively clear water of food particles comprising nauplii of the brine shrimp Artemia salina of about 600 μm in size. These were reduced to 50% of the initial concentration within 5 h and to 90% within 12 h. When N. norvegicus was offered food particles averaging 200 μm, a significant reduction in average size occurred, indicating that the minimum retention size is around 200 μm. Fluorescently dyed Artemia salina were recovered in the stomach and intestine of lobsters proving that the filtered particles are passed to the digestive tract. Results from other experiments, using the blood pigment (haemocyanin) concentration as an index of nutritional state, indicated that the lobsters can get some nutritional advantage from suspension feeding. Suspension feeding in larger decapods has not been described previously, so the significance of this finding is discussed with respect to changes in behavioural and ecological role.

  6. Conservation status of an imperiled crayfish, Faxonius marchandi Hobbs, 1948 (Decapoda: Cambaridae)

    USGS Publications Warehouse

    DiStefano, Robert J.; Magoulick, Daniel D.; Flinders, C.A.; Imhoff, Emily M.

    2017-01-01

    We summarize the distribution, ecology, threats, and conservation status of Faxonius marchandi (Hobbs, 1948), the Mammoth Spring crayfish, a limited-range endemic species to the Spring River drainage of Missouri and Arkansas, USA. The species is known from 51 locations on lower-order perennial and intermittent streams in only the eastern portion of the drainage. Faxonius marchandi is found in larger rocky substrates in shallower, slower-velocity habitats of well-buffered, mineral-rich streams. The invading alien crayfish Faxonius neglectus chaenodactylus (Williams, 1952) is the most likely threat to F. marchandi. These compiled data should serve as a baseline for future comparison, and facilitate discussion about future management, conservation, and research efforts.

  7. West Virginia crayfishes (Decapoda: Cambaridae): observations on distribution, natural history, and conservation

    USGS Publications Warehouse

    Loughman, Zachary J.; Simon, Thomas P.; Welsh, Stuart A.

    2009-01-01

    West Virginia's crayfishes have received moderate attention since publication of Jezerinac et al.'s (1995) monograph of the state fauna. Survey efforts were initiated over the summers of 2006 and 2007 to gather voucher material for the Indiana Biological Survey's Crustacean Collection. These collections have provided new information regarding the distribution, natural history, life history, taxonomy, and conservation status of Cambarus (Cambarus) carinirostris, C. (C.) bartonii cavatus, C. (C.) sciotensis, C. (Hiaticambarus) chasmodactylus, C. (H.) elkensis, C. (H.) longulus, C. (Jugicambarus) dubius, C. (Puncticambarus) robustus, Orconectes (Procericambarus) cristavarius, and O. (P.) rusticus. Orconectes (Faxonius) limosus has apparently been extirpated from West Virginia and should be removed from the state's list of extant crayfishes.

  8. West Virginia crayfishes (Decapoda: Cambaridae): observations on distribution, natural history, and conservation

    USGS Publications Warehouse

    Loughman, Zachary J.; Simon, Thomas P.; Welsh, Stuart A.

    2009-01-01

    West Virginia's crayfishes have received moderate attention since publication of Jezerinac et al.'s (1995) monograph of the state fauna. Survey efforts were initiated over the summers of 2006 and 2007 to gather voucher material for the Indiana Biological Survey's Crustacean Collection. These collections have provided new information regarding the distribution, natural history, life history, taxonomy, and conservation status of Cambarus (Cambarus) carinirostris, C. (C.) bartonii cavatus, C. (C.) sciotensis, C. (Hiaticambarus) chasmodactylus, C. (H.) elkensis, C. (H.) longulus, C. (Jugicambarus) dubius, C. (Puncticambarus) robustus, Orconectes (Procericambarus) cristavarius, and O. (P.) rusticus. Orconectes (Faxonius) limosus has apparently been extirpated from West Virginia and should be removed from the state's list of extant crayfishes.

  9. Ctenocheloides almeidai sp. nov., a new ghost shrimp from Brazil (Decapoda, Ctenochelidae).

    PubMed

    Anker, Arthur; Pachelle, Paulo P G

    2013-02-13

    A second species of the ctenochelid genus Ctenocheloides Anker, 2010 is described based on a single female specimen collected on a rocky reef in front of Maceió, Alagoas, northeastern Brazil. Ctenocheloides almeidai sp. nov. represents the first record of Ctenocheloides in the Atlantic Ocean. The new species differs from C. attenboroughi Anker, 2010, the type species from Madagascar, in the number of teeth in the crista dentata of the third maxilliped, the proportions and armature of the major and minor chelipeds, and several other characters. The microhabitats of C. almeidai sp. nov. and C. attenboroughi are remarkably similar: both species inhabit burrows made in rock crevices cemented by compact clay-like silt, at very shallow depths (1-1.5 m). A key to the western Atlantic species of the family Ctenochelidae is provided.

  10. Influence of starvation on the larval development of Hyas araneus (Decapoda, Majidae)

    NASA Astrophysics Data System (ADS)

    Anger, K.; Dawirs, R. R.

    1981-09-01

    The influence of starvation on larval development of the spider crab Hyas araneus (L.) was studied in laboratory experiments. No larval stage suffering from continual lack of food had sufficient energy reserves to reach the next instar. Maximal survival times were observed at four different constant temperatures (2°, 6°, 12° and 18 °C). In general, starvation resistance decreased as temperatures increased: from 72 to 12days in the zoea-1, from 48 to 18 days in the zoea-2, and from 48 to 15 days in the megalopa stage. The length of maximal survival is of the same order of magnitude as the duration of each instar at a given temperature. “Sublethal limits” of early starvation periods were investigated at 12 °C: Zoea larvae must feed right from the beginning of their stage (at high food concentration) and for more than one fifth, approximately, of that stage to have at least some chance of surviving to the next instar, independent of further prey availability. The minimum time in which enough reserves are accumulated for successfully completing the instar without food is called “point-of-reserve-saturation” (PRS). If only this minimum period of essential initial feeding precedes starvation, development in both zoeal stages is delayed and mortality is greater, when compared to the fed control. Starvation periods beginning right after hatching of the first zoea cause a prolongation of this instar and, surprisingly, a slight shortening of the second stage. The delay in the zoea-1 increases proportionally to the length of the initial fasting period. If more than approximately 70 % of the maximum possible survival time has elapsed without food supply, the larvae become unable to recover and to moult to the second stage even when re-fed (“point-of-no-return”, PNR). The conclusion, based on own observations and on literature data, is that initial feeding is of paramount importance in the early development of planktotrophic decapod larvae. Taking into account hormonal and other developmental processes during the first moult cycle, a general hypothesis is proposed to explain the key role of first food uptake as well as the response pattern of the zoea-1 stage to differential starvation periods.

  11. A new dwarf crayfish (Decapoda: Cambaridae) from floodplain swamps in central Alabama.

    PubMed

    Schuster, Guenter A; Kendrick, Michael R

    2017-03-05

    Cambarellus (Pandicambarus) rotatus, new species, is a dwarf crayfish from floodplain swamps in the Tombigbee and Black Warrior river drainages of Greene, Hale, and Marengo counties, Alabama. The new species is morphologically most similar to Cambarellus (Pandicambarus) lesliei. They differ in a several morphological characters. Cambarellus rotatus, new species, has gonopods that are rotated mesially so that the terminal elements oppose each other, and they have a short C-shaped sperm groove. These are unique features among known species of Cambarellus.

  12. Effects of habitat structure on the epifaunal community in Mussismilia corals: does coral morphology influence the richness and abundance of associated crustacean fauna?

    NASA Astrophysics Data System (ADS)

    Nogueira, Marcos M.; Neves, Elizabeth; Johnsson, Rodrigo

    2015-06-01

    Coral habitat structures increase abundance and richness of organisms by providing niches, easy access to resources and refuge from predators. Corals harbor a great variety of animals; the variation in coral species morphology contributes to the heterogeneity and complexity of habitat types. In this report, we studied the richness and abundance of crustaceans (Decapoda, Copepoda, Peracarida and Ostracoda) associated with three species of Mussismilia exhibiting different growth morphologies, in two different coral reefs of the Bahia state (Caramuanas and Boipeba-Moreré, Brazil). Mussismilia hispida is a massive coral; M. braziliensis also has a massive growth pattern, but forms a crevice in the basal area of the corallum; M. harttii has a meandroid pattern. PERMANOVA analysis suggests significant differences in associated fauna richness among Mussismilia species, with higher values for M. harttii, followed by M. braziliensis and later by M. hispida. The same trend was observed for density, except that the comparison of M. braziliensis and M. hispida did not show differences. Redundancy and canonical correspondence analysis indicated that almost all of the crustacean species were more associated with the M. harttii colonies that formed a group clearly separated from colonies of M. braziliensis and M. hispida. We also found that the internal volume of interpolyp space, only present in M. harttii, was the most important factor influencing richness and abundance of all analyzed orders of crustaceans.

  13. Spatiotemporal variation of macroinvertebrates in relation to canopy cover and other environmental factors in Eriora River, Niger Delta, Nigeria.

    PubMed

    Arimoro, Francis O; Obi-Iyeke, Grace E; Obukeni, Prince J O

    2012-10-01

    Canopy cover is well known to influence the distribution of macroinvertebrates in temperate streams. Very little is known about how this factor influences stream communities in Afrotropical streams. The effects and possible interactions of environmental factors and canopy cover on macroinvertebrate community structure (abundance, richness, and diversity) were examined in four stations in Eriora River, southern Nigeria bimonthly from May to November 2010. The river supported diverse macroinvertebrates in which the upstream sampling stations with dense canopy cover were dominated by Decapoda, Ephemeroptera, Odonata, Gastropoda, Trichoptera, and Coleoptera while Diptera and Coleoptera were the benthic organisms found predominant at downstream stations with less canopy cover. Some caddisfly species such as Agapetus agilis, Trichosetodes species and the stonefly Neoperla species were present upstream and were found to be potential bioindicators for a clean ecosystem. The blood worm Chironomus species and Tabanus sp. were abundant at the downstream of the river and are considered potential bioindicators for an organically degrading ecosystem. Some environmental factors varied temporally with significantly higher macroinvertebrate abundance and richness in May. We found out that canopy cover and environmental factors affected macroinvertebrates abundance, diversity, and richness and that the individual taxon had varying responses to these factors. These results help identify the mechanisms underlying the effects of canopy cover and other environmental factors on Afrotropical stream invertebrate communities.

  14. Spatial distribution of digestive proteinases in the midgut of the Pacific white shrimp (Litopenaeus vannamei) indicates the existence of endo-ectoperitrophic circulation in Crustacea.

    PubMed

    Alexandre, Daniel; Ozório, Renata A; Derner, Roberto B; Fracalossi, Débora M; Oliveira, Gabriel B; Samuels, Richard I; Terra, Walter R; Silva, Carlos P

    2014-01-01

    The effect of dietary protein concentration on the spatial distribution of digestive proteinases in the shrimp Litopenaeus vannamei indicates the existence of endo-ectoperitrophic enzyme circulation in this species. Samples recovered from the midgut gland tissues, stomach contents, three different portions of the midgut and feces were used for quantitative and qualitative analyses of the composition and distribution of the digestive proteinases. Animals were divided into three different groups: (1) animals (controls) fed with a commercial 35% protein diet, (2) animals fed with a commercial diet supplemented with ovalbumin to a final protein concentration of 60%; (3) animals fed with an 80% protein diet. Quantitative determinations using different substrates and zymograms showed that increasing protein concentration in the diet alters the distribution of proteinases along the digestive tract. Composition of proteinases in the midgut gland, stomach contents, midgut sections and feces were similar, but not identical. Chymotrypsin and trypsin paralogues were identified in all enzyme sources in a concentration gradient along the midgut in the control shrimp, the expected distribution supporting the existence of a recycling mechanism. The occurrence of a peritrophic membrane in other Decapoda suggests that endo-ectoperitrophic circulation of digestive enzymes and nutrients may also occur in other crustaceans and also extends beyond the Insecta. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Patterns in reef fish assemblages: Insights from the Chagos Archipelago

    PubMed Central

    Roche, Ronan; Koldewey, Heather; Turner, John

    2018-01-01

    Understanding the drivers of variability in the composition of fish assemblages across the Indo-Pacific region is crucial to support coral reef ecosystem resilience. Whilst numerous relationships and feedback mechanisms between the functional roles of coral reef fishes and reef benthic composition have been investigated, certain key groups, such as the herbivores, are widely suggested to maintain reefs in a coral-dominated state. Examining links between fishes and reef benthos is complicated by the interactions between natural processes, disturbance events and anthropogenic impacts, particularly fishing pressure. This study examined fish assemblages and associated benthic variables across five atolls within the Chagos Archipelago, where fishing pressure is largely absent, to better understand these relationships. We found high variability in fish assemblages among atolls and sites across the archipelago, especially for key groups such as a suite of grazer-detritivore surgeonfish, and the parrotfishes which varied in density over 40-fold between sites. Differences in fish assemblages were significantly associated with variable levels of both live and recently dead coral cover and rugosity. We suggest these results reflect differing coral recovery trajectories following coral bleaching events and a strong influence of ‘bottom-up’ control mechanisms on fish assemblages. Species level analyses revealed that Scarus niger, Acanthurus nigrofuscus and Chlorurus strongylocephalos were key species driving differences in fish assemblage structure. Clarifying the trophic roles of herbivorous and detritivorous reef fishes will require species-level studies, which also examine feeding behaviour, to fully understand their contribution in maintaining reef resilience to climate change and fishing impacts. PMID:29351566

  16. Patterns in reef fish assemblages: Insights from the Chagos Archipelago.

    PubMed

    Samoilys, Melita; Roche, Ronan; Koldewey, Heather; Turner, John

    2018-01-01

    Understanding the drivers of variability in the composition of fish assemblages across the Indo-Pacific region is crucial to support coral reef ecosystem resilience. Whilst numerous relationships and feedback mechanisms between the functional roles of coral reef fishes and reef benthic composition have been investigated, certain key groups, such as the herbivores, are widely suggested to maintain reefs in a coral-dominated state. Examining links between fishes and reef benthos is complicated by the interactions between natural processes, disturbance events and anthropogenic impacts, particularly fishing pressure. This study examined fish assemblages and associated benthic variables across five atolls within the Chagos Archipelago, where fishing pressure is largely absent, to better understand these relationships. We found high variability in fish assemblages among atolls and sites across the archipelago, especially for key groups such as a suite of grazer-detritivore surgeonfish, and the parrotfishes which varied in density over 40-fold between sites. Differences in fish assemblages were significantly associated with variable levels of both live and recently dead coral cover and rugosity. We suggest these results reflect differing coral recovery trajectories following coral bleaching events and a strong influence of 'bottom-up' control mechanisms on fish assemblages. Species level analyses revealed that Scarus niger, Acanthurus nigrofuscus and Chlorurus strongylocephalos were key species driving differences in fish assemblage structure. Clarifying the trophic roles of herbivorous and detritivorous reef fishes will require species-level studies, which also examine feeding behaviour, to fully understand their contribution in maintaining reef resilience to climate change and fishing impacts.

  17. Variability in isotope discrimination factors in coral reef fishes: implications for diet and food web reconstruction.

    PubMed

    Wyatt, Alex S J; Waite, Anya M; Humphries, Stuart

    2010-10-27

    Interpretation of stable isotope ratios of carbon and nitrogen (δ(13)C and δ(15)N) is generally based on the assumption that with each trophic level there is a constant enrichment in the heavier isotope, leading to diet-tissue discrimination factors of 3.4‰ for (15)N (ΔN) and ∼0.5‰ for (13)C (ΔC). Diet-tissue discrimination factors determined from paired tissue and gut samples taken from 152 individuals from 26 fish species at Ningaloo Reef, Western Australia demonstrate a large amount of variability around constant values. While caution is necessary in using gut contents to represent diet due to the potential for high temporal variability, there were significant effects of trophic position and season that may also lead to variability in ΔN under natural conditions. Nitrogen enrichment increased significantly at higher trophic levels (higher tissue δ(15)N), with significantly higher ΔN in carnivorous species. Changes in diet led to significant changes in ΔN, but not tissue δ(15)N, between seasons for several species: Acanthurus triostegus, Chromis viridis, Parupeneus signatus and Pomacentrus moluccensis. These results confirm that the use of meta-analysis averages for ΔN is likely to be inappropriate for accurately determining diets and trophic relationships using tissue stable isotope ratios. Where feasible, discrimination factors should be directly quantified for each species and trophic link in question, acknowledging the potential for significant variation away from meta-analysis averages and, perhaps, controlled laboratory diets and conditions.

  18. Gigantism in a Bacterium, Epulopiscium fishelsoni, Correlates with Complex Patterns in Arrangement, Quantity, and Segregation of DNA

    PubMed Central

    Bresler, V.; Montgomery, W. L.; Fishelson, L.; Pollak, P. E.

    1998-01-01

    Epulopiscium fishelsoni, gut symbiont of the brown surgeonfish (Acanthurus nigrofuscus) in the Red Sea, attains a larger size than any other eubacterium, varies 10- to 20-fold in length (and >2,000-fold in volume), and undergoes a complex daily life cycle. In early morning, nucleoids contain highly condensed DNA in elongate, chromosome-like structures which are physically separated from the general cytoplasm. Cell division involves production of two (rarely three) nucleoids within a cell, deposition of cell walls around expanded nucleoids, and emergence of daughter cells from the parent cell. Fluorescence measurements of DNA, RNA, and other cell components indicate the following. DNA quantity is proportional to cell volume over cell lengths of ∼30 μm to >500 μm. For cells of a given size, nucleoids of cells with two nucleoids (binucleoid) contain approximately equal amounts of DNA. And each nucleoid of a binucleoid cell contains one-half the DNA of the single nucleoid in a uninucleoid cell of the same size. The life cycle involves approximately equal subdivision of DNA among daughter cells, formation of apical caps of condensed DNA from previously decondensed and diffusely distributed DNA, and “pinching” of DNA near the middle of the cell in the absence of new wall formation. Mechanisms underlying these patterns remain unclear, but formation of daughter nucleoids and cells occurs both during diurnal periods of host feeding and bacterial cell growth and during nocturnal periods of host inactivity when mean bacterial cell size declines. PMID:9791108

  19. [Reproduction of the pink shrimp Farfantepenaeus notialis (Decapoda: Penaeidae) in the Colombian Caribbean].

    PubMed

    Paramo, Jorge; Pérez, Daniel; Wolff, Matthias

    2014-06-01

    The shallow water pink shrimp (Farfantepenaeus notialis) is among the socioeconomically most important resources of the Caribbean. The lack of biological and fishery information is of great concern for the fisheries management authorities. The presented study therefore aimed at the investigation of the reproductive cycle, the size composition and the size at first maturity of this species as a basis for the ordination and management of this resource. The study was conducted from June 2012 to May 2013 off the coast of the Caribbean Sea of Colombia. A total of 5 356 individuals were collected, identified, classified and preserved for their subsequent analysis in the laboratory. Size, weight, sex and gonad stage were recorded for each specimen. Significant differences were found in sex ratio in all months sampled with a clear predominance of females. Mature females were found year-around, but two reproductive peaks were identified during the periods October-December and April-June. The mean catch total length size (MCS) for females and males was 148.00mm and 122.54mm, respectively. The mean size at maturity (LT50%) was 129.34mm for females and 97.77mm for males. MCS was always above LT50% for both sexes. Considering the large reduction in fishing effort in the Colombian Caribbean Sea over the last years, we could expect that the shrimp population is in a rebuilding process or perhaps it may be already restored.

  20. Multiple drivers of decline in the global status of freshwater crayfish (Decapoda: Astacidea).

    PubMed

    Richman, Nadia I; Böhm, Monika; Adams, Susan B; Alvarez, Fernando; Bergey, Elizabeth A; Bunn, John J S; Burnham, Quinton; Cordeiro, Jay; Coughran, Jason; Crandall, Keith A; Dawkins, Kathryn L; DiStefano, Robert J; Doran, Niall E; Edsman, Lennart; Eversole, Arnold G; Füreder, Leopold; Furse, James M; Gherardi, Francesca; Hamr, Premek; Holdich, David M; Horwitz, Pierre; Johnston, Kerrylyn; Jones, Clive M; Jones, Julia P G; Jones, Robert L; Jones, Thomas G; Kawai, Tadashi; Lawler, Susan; López-Mejía, Marilu; Miller, Rebecca M; Pedraza-Lara, Carlos; Reynolds, Julian D; Richardson, Alastair M M; Schultz, Mark B; Schuster, Guenter A; Sibley, Peter J; Souty-Grosset, Catherine; Taylor, Christopher A; Thoma, Roger F; Walls, Jerry; Walsh, Todd S; Collen, Ben

    2015-02-19

    Rates of biodiversity loss are higher in freshwater ecosystems than in most terrestrial or marine ecosystems, making freshwater conservation a priority. However, prioritization methods are impeded by insufficient knowledge on the distribution and conservation status of freshwater taxa, particularly invertebrates. We evaluated the extinction risk of the world's 590 freshwater crayfish species using the IUCN Categories and Criteria and found 32% of all species are threatened with extinction. The level of extinction risk differed between families, with proportionally more threatened species in the Parastacidae and Astacidae than in the Cambaridae. Four described species were Extinct and 21% were assessed as Data Deficient. There was geographical variation in the dominant threats affecting the main centres of crayfish diversity. The majority of threatened US and Mexican species face threats associated with urban development, pollution, damming and water management. Conversely, the majority of Australian threatened species are affected by climate change, harvesting, agriculture and invasive species. Only a small proportion of crayfish are found within the boundaries of protected areas, suggesting that alternative means of long-term protection will be required. Our study highlights many of the significant challenges yet to come for freshwater biodiversity unless conservation planning shifts from a reactive to proactive approach.

  1. New records of coral-associated crabs (Decapoda: Brachyura: Carpilioidea, Trapezoidea) from Easter Island.

    PubMed

    Boyko, Christopher B; Mendoza, Jose C E; Castro, Peter

    2017-01-10

    A review is made of those brachyurans that are symbiotic or otherwise associated with scleractinian corals on Easter Island, southeastern Pacific Ocean. A total of seven species is reported, including three species from two families not previously known from the island. Earlier records of Trapezia are analyzed and, although as many as six species have been previously reported, we conclude that only three species are known to occur on the island with certainty.

  2. Structural changes of oviduct of freshwater shrimp, Macrobrachium nipponense (Decapoda, Palaemonidae), during spawning*

    PubMed Central

    Lu, Jian-ping; Zhang, Xiao-hui; Yu, Xiao-yun

    2006-01-01

    The structural change of the oviduct of freshwater shrimp (Macrobrachium nipponense) during spawning was examined by electron microscopy. The oviduct wall structural characteristics seem to be influenced significantly by the spawning process. Before the parturition and ovulation, two types of epithelial cells (types I and II) are found in the epithelium. The free surfaces of type I and type II cells have very dense long microvilli. Under the type I and type II cells, are a relatively thick layer of secreting material and a layer of mostly dead cells. After ovulation, two other types of epithelial cells (types III and IV) are found in the oviduct wall epithelium. The free surface of type III cells only has short microvilli scattered on the surface. The thick layer with secreting material and the dead cell layer disappeared at this stage. In some type III cells, the leaking out of cytoplasm from broken cell membrane led to the death of these type III cells. The transformation of all four types of epithelial cells was in the order: IV→I→II→III. PMID:16365928

  3. Multiple drivers of decline in the global status of freshwater crayfish (Decapoda: Astacidea)

    PubMed Central

    Richman, Nadia I.; Böhm, Monika; Adams, Susan B.; Alvarez, Fernando; Bergey, Elizabeth A.; Bunn, John J. S.; Burnham, Quinton; Cordeiro, Jay; Coughran, Jason; Crandall, Keith A.; Dawkins, Kathryn L.; DiStefano, Robert J.; Doran, Niall E.; Edsman, Lennart; Eversole, Arnold G.; Füreder, Leopold; Furse, James M.; Gherardi, Francesca; Hamr, Premek; Holdich, David M.; Horwitz, Pierre; Johnston, Kerrylyn; Jones, Clive M.; Jones, Julia P. G.; Jones, Robert L.; Jones, Thomas G.; Kawai, Tadashi; Lawler, Susan; López-Mejía, Marilu; Miller, Rebecca M.; Pedraza-Lara, Carlos; Reynolds, Julian D.; Richardson, Alastair M. M.; Schultz, Mark B.; Schuster, Guenter A.; Sibley, Peter J.; Souty-Grosset, Catherine; Taylor, Christopher A.; Thoma, Roger F.; Walls, Jerry; Walsh, Todd S.; Collen, Ben

    2015-01-01

    Rates of biodiversity loss are higher in freshwater ecosystems than in most terrestrial or marine ecosystems, making freshwater conservation a priority. However, prioritization methods are impeded by insufficient knowledge on the distribution and conservation status of freshwater taxa, particularly invertebrates. We evaluated the extinction risk of the world's 590 freshwater crayfish species using the IUCN Categories and Criteria and found 32% of all species are threatened with extinction. The level of extinction risk differed between families, with proportionally more threatened species in the Parastacidae and Astacidae than in the Cambaridae. Four described species were Extinct and 21% were assessed as Data Deficient. There was geographical variation in the dominant threats affecting the main centres of crayfish diversity. The majority of threatened US and Mexican species face threats associated with urban development, pollution, damming and water management. Conversely, the majority of Australian threatened species are affected by climate change, harvesting, agriculture and invasive species. Only a small proportion of crayfish are found within the boundaries of protected areas, suggesting that alternative means of long-term protection will be required. Our study highlights many of the significant challenges yet to come for freshwater biodiversity unless conservation planning shifts from a reactive to proactive approach. PMID:25561679

  4. Feeding preference of the South American endemic anomuran Aegla platensis (Decapoda, Anomura, Aeglidae)

    NASA Astrophysics Data System (ADS)

    Colpo, Karine Delevati; Ribeiro, Liara Colpo; Wesz, Bruna; Ribeiro, Ludmilla Oliveira

    2012-04-01

    In order to determine the feeding preference of Aegla platensis in streams and the importance of microorganisms in its detritivore diet, we carried out two experiments designed to evaluate the food preferences of A. platensis (1) among leaves with different levels of microbial colonization and (2) among insect larvae (Chironomidae, Simuliidae, Hydropsychidae) and microbially conditioned leaves. A. platensis preferred animal over plant food items; when only leaves were offered, this aeglid preferred the leaves with higher levels of microorganism conditioning.

  5. Effects of ammonia stress in the Amazon river shrimp Macrobrachium amazonicum (Decapoda, Palaemonidae).

    PubMed

    Pinto, Marcelo R; Lucena, Malson N; Faleiros, Rogério Oliveira; Almeida, Eduardo Alves; McNamara, John C; Leone, Francisco A

    2016-01-01

    We evaluate the effects of total ammonia nitrogen-N (TAN) exposure for 72h on (Na(+),K(+))- and V(H(+))-ATPase activities and on their subunit expressions in gills of the diadromous freshwater shrimp Macrobrachium amazonicum. Specific (Na(+),K(+))- and V(H(+))-ATPase activities increased roughly 1.5- to 2-fold, respectively, after exposure to 2.0mmolL(-1) TAN. Quantitative RT-PCR analyses revealed a 2.5-fold increase in V(H(+))-ATPase B subunit mRNA expression while (Na(+),K(+))-ATPase α-subunit expression was unchanged. Immunohistochemical analyses of the gill lamellae located the (Na(+),K(+))-ATPase throughout the intralamellar septal cells, independently of TAN concentration, while the V(H(+))-ATPase was located in both the apical pillar cell flanges and pillar cell bodies. Systemic stress parameters like total hemocyte count decreased by 30% after exposure to 2.0mmolL(-1) TAN, accompanied by increased activities of the oxidative stress enzymes superoxide dismutase, glutathione reductase and glucose-6-phosphate dehydrogenase in the gills. The stress responses of M. amazonicum to elevated TAN include increases in gill (Na(+),K(+))- and V(H(+))-ATPase activities that are accompanied by changes in oxidative stress enzyme activities, immune system effects and an increase in gill V(H(+))-ATPase gene expression. These findings likely underpin physiological effects in a crustacean like M. amazonicum that exploits multiple ecosystems during its life cycle, as well as under culture conditions that may significantly impact shrimp production by the aquaculture industry. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Multiple drivers of decline in the global status of freshwater crayfish (Decapoda:Astacidea)

    Treesearch

    Nadia I. Richman; Monika Böhm; Susan B. Adams; Fernando Alvarez; Elizabeth A. Bergey; John J. S. Bunn; Quinton Burnham; Jay Cordeiro; Jason Coughran; Keith A. Crandall; Kathryn L. Dawkins; Robert J. DiStefano; Niall E. Doran; Lennart Edsman; Arnold G. Eversole; Leopold Füreder; James M. Furse; Francesca Gherardi; Premek Hamr; David M. Holdich; Pierre Horwitz; Kerrylyn Johnston; Clive M. Jones; Julia P. G. Jones; Robert L. Jones; Thomas G. Jones; Tadashi Kawai; Susan Lawler; Marilu López-Mejía; Rebecca M. Miller; Carlos Pedraza-Lara; Julian D. Reynolds; Alastair M. M. Richardson; Mark B. Schultz; Guenter A. Schuster; Peter J. Sibley; Catherine Souty-Grosset; Christopher A. Taylor; Roger F. Thoma; Jerry Walls; Todd S. Walsh; Ben Cohen

    2015-01-01

    Rates of biodiversity loss are higher in freshwater ecosystems than in most terrestrial or marine ecosystems, making freshwater conservation a priority. However, prioritization methods are impeded by insufficient knowledge on the distribution and conservation status of freshwater taxa, particularly invertebrates. We evaluated the extinction risk of the world’s 590...

  7. In vitro fertilization of the rock shrimp, Rhynchocinetes typus (Decapoda, Caridea): a review.

    PubMed

    Dupré, Enrique M; Barros, Claudio

    2011-01-01

    This review compiles all the research done on gametes and fertilization in the rock shrimp, R. typus, and describes the sequence of events from the first gamete interaction to zygote formation and the first cleavage of the embryo, with light, fluorescence confocal and electron microscopes. Early studies showed that sperm from the vas deferens have a tack-shape with a "needle-like process" or rigid spike (RS) that extends from a semi-spherical body that contains the arms with chromatin and spines. Upon contact with seawater and by action of Na +, the arms and spines extend, producing an inverted umbrella form of the spermatozoa. The first sperm-oocyte interaction occurs between protein receptors type lectins of the sperm RS and oocyte chorion sperm ligands. These ligands contain residues of α-Glu, Man (α 1-3) Man, α and β-GlcNAc and α-GalNA terminal residues. It was found that α-Man and GlcNAc residues are the ligands that are directly related to the adhesion process and further penetration of sperm. After this first interaction, the RS enters the oocyte envelope by the action of a trypsin-like enzyme, rhynchocinecine, present in the acicular process. Later, arms and spines penetrate the oocyte cytoplasm, where the chromatin of the arms begin to migrate to the central area of the sperm, condensing in a cup-shaped structure near the connecting piece, which forms the male pronucleus.

  8. Distribution of the planktonic shrimp Lucifer (Thompson, 1829) (Decapoda, Sergestoidea) off the Amazon.

    PubMed

    Melo, N F A C; Neumann-Leitão, S; Gusmão, L M O; Martins-Neto, F E; Palheta, G D A

    2014-08-01

    Lucifer faxoni (BORRADAILE, 1915) and L. typus (EDWARDS, 1837) are species first identified in the neritic and oceanic waters off the Amazon. Samplings were made aboard the vessel "Antares" at 22 stations in July and August, 2001 with a bongo net (500-µm mesh size). Hydrological data were taken simultaneously for comparative purposes. L. faxoni was present at thirteen of the fourteen neritic stations analysed, as well as at five of the eight oceanic stations. L. typus was present at three of the fourteen neritic stations and in one of the eight oceanic stations. The highest density of L. faxoni in the neritic province was 7,000 ind.m(-3) (St. 82) and 159 ind.m(-3) (St. 75) in the oceanic area. For L. typus, the highest density observed was 41 ind.m(-3) (St. 64) in the neritic province. In the oceanic province, the highest single density value was recorded at station 75 (5 ind.m(-3)). Overall, L. faxoni typically presented the highest densities.

  9. Breeding period in the mangrove crab Goniopsis cruentata (Decapoda: Grapsidae) in Northeast Brazil.

    PubMed

    de Lira, José Jonathas Pereira Rodrigues; Calado, Tereza Cristina dos Santos; de Araújo, Marina de Sá Leitão Câmara

    2013-03-01

    The brachyuran crabs are iteroparous species which present a high diversification of reproduction patterns, which may have evolved as a species-specific response to environmental conditions. Tropical species commonly present a year-round reproduction due to stable environment conditions. Goniopsis cruentata is a crab species widely distributed along the Western Atlantic, inhabiting practically every microhabitat in the mangrove ecosystem. The aim of the present study is to determine the breeding period of the crab Goniopsis cruentata in Northeastern Brazil and also to evaluate the influence of water salinity, rainfall and air and water temperature on it. A total of 71 ovigerous females, captured from August-2007 to July-2008, were used to assess the breeding period of this species. It was analyzed by the monthly proportion of ovigerous females. A correlation was applied to verify the influence of the abiotic factors on the breeding period. The present population bred seasonal-continuously with peaks in the dry period, which was not associated with monthly variations of salinity, rainfall and air and water temperatures. Therefore, according to statistical analyses, our hypothesis was refuted. However, breeding was intensified in the dry period, when salinity and temperatures were higher and rainfall was lower. We conclude that, even though breeding is not related to monthly variation of environmental factors, it occurs in periods of higher salinity and temperatures and lower rainfall.

  10. Genomic signatures of geographic isolation and natural selection in coral reef fishes.

    PubMed

    Gaither, Michelle R; Bernal, Moisés A; Coleman, Richard R; Bowen, Brian W; Jones, Shelley A; Simison, W Brian; Rocha, Luiz A

    2015-04-01

    The drivers of speciation remain among the most controversial topics in evolutionary biology. Initially, Darwin emphasized natural selection as a primary mechanism of speciation, but the architects of the modern synthesis largely abandoned that view in favour of divergence by geographic isolation. The balance between selection and isolation is still at the forefront of the evolutionary debate, especially for the world's tropical oceans where biodiversity is high, but isolating barriers are few. Here, we identify the drivers of speciation in Pacific reef fishes of the genus Acanthurus by comparative genome scans of two peripheral populations that split from a large Central-West Pacific lineage at roughly the same time. Mitochondrial sequences indicate that populations in the Hawaiian Archipelago and the Marquesas Islands became isolated approximately 0.5 Ma. The Hawaiian lineage is morphologically indistinguishable from the widespread Pacific form, but the Marquesan form is recognized as a distinct species that occupies an unusual tropical ecosystem characterized by upwelling, turbidity, temperature fluctuations, algal blooms and little coral cover. An analysis of 3737 SNPs reveals a strong signal of selection at the Marquesas, with 59 loci under disruptive selection including an opsin Rh2 locus. While both the Hawaiian and Marquesan populations indicate signals of drift, the former shows a weak signal of selection that is comparable with populations in the Central-West Pacific. This contrast between closely related lineages reveals one population diverging due primarily to geographic isolation and genetic drift, and the other achieving taxonomic species status under the influence of selection. © 2015 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  11. Coral reef fishes exhibit beneficial phenotypes inside marine protected areas

    PubMed Central

    Carroll, Jessica; Rynerson, Kristen W.; Matthews, Danielle F.; Turingan, Ralph G.

    2018-01-01

    Human fishing effort is size-selective, preferentially removing the largest individuals from harvested stocks. Intensive, size-specific fishing mortality induces directional shifts in phenotypic frequencies towards the predominance of smaller and earlier-maturing individuals, which are among the primary causes of declining fish biomass. Fish that reproduce at smaller size and younger age produce fewer, smaller, and less viable larvae, severely reducing the reproductive capacity of harvested populations. Marine protected areas (MPAs) are extensively utilized in coral reefs for fisheries management, and are thought to mitigate the impacts of size-selective fishing mortality and supplement fished stocks through larval export. However, empirical evidence of disparities in fitness-relevant phenotypes between MPAs and adjacent fished reefs is necessary to validate this assertion. Here, we compare key life-history traits in three coral-reef fishes (Acanthurus nigrofuscus, Ctenochaetus striatus, and Parupeneus multifasciatus) between MPAs and fished reefs in the Philippines. Results of our analyses support previous hypotheses regarding the impacts of MPAs on phenotypic traits. Asymptotic length (Linf) and growth rates (K) differed between conspecifics in MPAs and fished reefs, with protected populations exhibiting phenotypes that are known to confer higher fecundity. Additionally, populations demonstrated increases in length at 50% maturity (L50) inside MPAs compared to adjacent areas, although age at 50% maturity (A50) did not appear to be impacted by MPA establishment. Shifts toward advantageous phenotypes were most common in the oldest and largest MPAs, but occurred in all of the MPAs examined. These results suggest that MPAs may provide protection against the impacts of size-selective harvest on life-history traits in coral-reef fishes. PMID:29470525

  12. Flux of heavy metal accumulation in various organs of the intertidal marine blue crab, Portunus pelagicus (L.) from the Kuwait coast after the Gulf War.

    PubMed

    Al-Mohanna, S Y; Subrahmanyam, M N

    2001-10-01

    The metal levels of arsenic, chromium, copper, lead, magnesium, manganese, selenium, vanadium, and zinc concentrations were determined in various body organs, viz., hepatopancreas, gills, gonad, gastric stomach, and muscle of the blue crab, Portunus pelagicus (Crustacea: Decapoda) to assess the bioaccumulation of metals associated with petroleum input a decade after the 1991 Gulf War oil spillage. Sample solutions prepared were analyzed using an atomic absorption spectrophotometry. High concentrations of Zn and Cu in the muscle and hepatopancreas tissues were a strong indicative of high exposure of P. pelagicus to these metals. However, muscle tissue had been found to accumulate the highest values for all metal speciations analyzed. Copper, zinc, and chromium in samples collected from Station II covering the Kuwait City area were often in excess of those present in Station I and III. Arsenic, lead, magnesium, manganese, selenium, and vanadium were greater in individuals obtained from Station I. A significant correlation was found to exist between Se and V in crab muscle with a surge in Se metal concentration, which was found to be inversely proportional to that of V metal concentration irrespective of the sex of the crab. The difference in patterns of metal occurrence and the significant increase in the Cu and Zn concentrations in various organs of the crab were largely associated with the 1991 Gulf War oil spill. Such results could be used as a baseline for the monitoring of the level of metals in marine organisms of future studies.

  13. A new yeti crab phylogeny: Vent origins with indications of regional extinction in the East Pacific

    PubMed Central

    Liu, Xinming; Lin, Rongcheng; Li, Xinzheng; Won, Yong-Jin

    2018-01-01

    The recent discovery of two new species of kiwaid squat lobsters on hydrothermal vents in the Pacific Ocean and in the Pacific sector of the Southern Ocean has prompted a re-analysis of Kiwaid biogeographical history. Using a larger alignment with more fossil calibrated nodes than previously, we consider the precise relationship between Kiwaidae, Chirostylidae and Eumunididae within Chirostyloidea (Decapoda: Anomura) to be still unresolved at present. Additionally, the placement of both new species within a new “Bristly” clade along with the seep-associated Kiwa puravida is most parsimoniously interpreted as supporting a vent origin for the family, rather than a seep-to-vent progression. Fossil-calibrated divergence analysis indicates an origin for the clade around the Eocene-Oligocene boundary in the eastern Pacific ~33–38 Ma, coincident with a lowering of bottom temperatures and increased ventilation in the Pacific deep sea. Likewise, the mid-Miocene (~10–16 Ma) rapid radiation of the new Bristly clade also coincides with a similar cooling event in the tropical East Pacific. The distribution, diversity, tree topology and divergence timing of Kiwaidae in the East Pacific is most consistent with a pattern of extinctions, recolonisations and radiations along fast-spreading ridges in this region and may have been punctuated by large-scale fluctuations in deep-water ventilation and temperature during the Cenozoic; further affecting the viability of Kiwaidae populations along portions of mid-ocean ridge. PMID:29547631

  14. Structure and Ultrastructure of the Endodermal Region of the Alimentary Tract in the Freshwater Shrimp Neocaridina heteropoda (Crustacea, Malacostraca)

    PubMed Central

    Sonakowska, Lidia; Włodarczyk, Agnieszka; Poprawa, Izabela; Binkowski, Marcin; Śróbka, Joanna; Kamińska, Karolina; Kszuk-Jendrysik, Michalina; Chajec, Łukasz; Zajusz, Bartłomiej; Rost-Roszkowska, Magdalena Maria

    2015-01-01

    The freshwater shrimp Neocaridina heteropoda (Crustacea, Malacostraca, Decapoda) originates from Asia and is one of the species that is widely available all over the world because it is the most popular shrimp that is bred in aquaria. The structure and the ultrastructure of the midgut have been described using X-ray microtomography, transmission electron microscopy, light and fluorescence microscopes. The endodermal region of the alimentary system in N. heteropoda consists of an intestine and a hepatopancreas. No differences were observed in the structure and ultrastructure of males and females of the shrimp that were examined. The intestine is a tube-shaped organ and the hepatopancreas is composed of two large diverticles that are divided into the blind-end tubules. Hepatopancreatic tubules have three distinct zones – proximal, medial and distal. Among the epithelial cells of the intestine, two types of cells were distinguished – D and E-cells, while three types of cells were observed in the epithelium of the hepatopancreas – F, B and E-cells. Our studies showed that the regionalization in the activity of cells occurs along the length of the hepatopancreatic tubules. The role and ultrastructure of all types of epithelial cells are discussed, with the special emphasis on the function of the E-cells, which are the midgut regenerative cells. Additionally, we present the first report on the existence of an intercellular junction that is connected with the E-cells of Crustacea. PMID:25996951

  15. Systematics, phylogeny, and taphonomy of ghost shrimps (Decapoda): a perspective from the fossil record

    PubMed Central

    Klompmaker, Adiël A.

    2016-01-01

    Ghost shrimps of Callianassidae and Ctenochelidae are soft-bodied, usually heterochelous decapods representing major bioturbators of muddy and sandy (sub)marine substrates. Ghost shrimps have a robust fossil record spanning from the Early Cretaceous (~ 133 Ma) to the Holocene and their remains are present in most assemblages of Cenozoic decapod crustaceans. Their taxonomic interpretation is in flux, mainly because the generic assignment is hindered by their insufficient preservation and disagreement in the biological classification. Furthermore, numerous taxa are incorrectly classified within the catch-all taxon Callianassa. To show the historical patterns in describing fossil ghost shrimps and to evaluate taphonomic aspects influencing the attribution of ghost shrimp remains to higher level taxa, a database of all fossil species treated at some time as belonging to the group has been compiled: 250 / 274 species are considered valid ghost shrimp taxa herein. More than half of these taxa (160 species, 58.4%) are known only from distal cheliped elements, i.e., dactylus and / or propodus, due to the more calcified cuticle locally. Rarely, ghost shrimps are preserved in situ in burrows or in direct association with them, and several previously unpublished occurrences are reported herein. For generic assignment, fossil material should be compared to living species because many of them have modern relatives. Heterochely, intraspecific variation, ontogenetic changes and sexual dimorphism are all factors that have to be taken into account when working with fossil ghost shrimps. Distal elements are usually more variable than proximal ones. Preliminary results suggest that the ghost shrimp clade emerged not before the Hauterivian (~ 133 Ma). The divergence of Ctenochelidae and Paracalliacinae is estimated to occur within the interval of Hauterivian to Albian (133–100 Ma). Callichirinae and Eucalliacinae likely diverged later during the Late Cretaceous (100–66 Ma), whereas Callianassinae did not appear before the Eocene (56 Ma). PMID:27499814

  16. Zoogeography, taxonomy, and conservation of West Virginia’s Ohio River floodplain crayfishes (Decapoda, Cambaridae)

    PubMed Central

    Loughman, Zachary J.; Simon, Thomas P.

    2011-01-01

    Abstract The crayfish fauna of West Virginia consists of 23 species and several undescribed taxa. Most survey efforts documenting this fauna have been conducted in lotic waterways throughout the Appalachian plateau, Allegheny Mountains, and Ridge and Valley physiographic provinces. Bottomland forests, swamps, and marshes associated with large river floodplain such as the Ohio River floodplain historically have been under-surveyed in the state. These habitats harbor the richest primary burrowing crayfish fauna in West Virginia, and are worthy of survey efforts. In an effort to fill this void, the crayfish fauna of West Virginia’s Ohio River floodplain was surveyed from 2004 through 2009. From this survey, nine species from four genera were documented inhabiting the floodplain. Zoogeography, biology, and conservation status is provided for all nine crayfishes. The dominant genus along the floodplain is Cambarus, which includes Cambarus (Cambarus) carinirostris, Cambarus (Cambarus) bartonii cavatus, Cambarus (Procambarus) robustus and Cambarus (Tubericambarus) thomai. Cambarus (Tubericambarus) thomai is the most prevalent burrowing species occurring along the floodplain. The genus Orconectes consists of two native species, Orconectes (Cambarus) obscurus and Orconectes (Cambarus) sanbornii; and two invasive taxa, Orconectes (Gremicambarus) virilis and Orconectes (Procambarus) rusticus. Orconectes (Cambarus) obscurus has experienced a range extension to the south and occupies streams formerly occupied by Orconectes (Cambarus) sanbornii. Both invasive taxa were allied with anthropogenic habitats and disturbance gradients. The genera Fallicambarus and Procambarus are represented by a single species. Both Fallicambarus (Cambarus) fodiens and Procambarus (Orconectes) acutus are limited to the historic preglacial Marietta River Valley. PMID:21594135

  17. Leptalpheus pereirai sp. nov., a new alpheid shrimp from Panama and Venezuela (Decapoda: Caridea).

    PubMed

    Anker, Arthur; Caripe, Jonathan Vera

    2016-06-22

    A new species of the infaunal alpheid shrimp genus Leptalpheus Williams, 1965 is described based on material from three localities on the Caribbean coast of Panama and Isla Chimana Grande, Venezuela. Leptalpheus pereirai sp. nov. belongs to a group of species characterised by the presence of well-developed adhesive disks on the major chela and appears to dwell in burrows of the large callianassid ghost shrimp, Glypturus acanthochirus Stimpson 1866.

  18. Molecular phylogeny of Pasiphaeidae (Crustacea, Decapoda, Caridea) reveals systematic incongruence of the current classification.

    PubMed

    Liao, Yunshi; De Grave, Sammy; Ho, Tsz Wai; Ip, Brian H Y; Tsang, Ling Ming; Chan, Tin-Yam; Chu, Ka Hou

    2017-10-01

    Caridean shrimps constitute one of the most diverse groups of decapod crustaceans, notwithstanding their poorly resolved infraordinal relationships. One of the systematically controversial families in Caridea is the predominantly pelagic Pasiphaeidae, comprises 101 species in seven genera. Pasiphaeidae species exhibit high morphological disparity, as well as ecological niche width, inhabiting shallow to very deep waters (>4000m). The present work presents the first molecular phylogeny of the family, based on a combined dataset of six mitochondrial and nuclear gene markers (12S rDNA, 16S rDNA, histone 3, sodium-potassium ATPase α-subunit, enolase and ATP synthase β-subunit) from 33 species belonged to six genera of Pasiphaeidae with 19 species from 12 other caridean families as outgroup taxa. Maximum likelihood and Bayesian inference analyses conducted on the concatenated dataset of 2265bp suggest the family Pasiphaeidae is not monophyletic, with Psathyrocaris more closely related to other carideans than to the other five pasiphaeid genera included in this analysis. Leptochela occupies a sister position to the remaining genera and is genetically quite distant from them. At the generic level, the analysis supports the monophyly of Pasiphaea, Leptochela and Psathyrocaris, while Eupasiphae is shown to be paraphyletic, closely related to Parapasiphae and Glyphus. The present molecular result strongly implies that certain morphological characters used in the present systematic delineation within Pasiphaeidae may not be synapomorphies and the classification within the family needs to be urgently revised. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. A potential vector of domoic acid: the swimming crab Polybius henslowii Leach (Decapoda-brachyura).

    PubMed

    Costa, Pedro R; Rodrigues, Susana M; Botelho, Maria J; Sampayo, Maria Antónia de M

    2003-08-01

    The swimming crab Polybius henslowii may play an important role in the movement of the amnesic shellfish toxin, domoic acid (DA), through the marine food chain. High DA concentrations have been determined in crab samples harvested along the Portuguese coast during the summer of 2002, reaching a level of 323.1 microg DA/g crab tissue. Toxin distribution in the different crab organs showed levels as high as 571.6 microg DA/g in the visceral tissues. Levels of toxin 4-12 times lower were detected in the remaining tissues. This crab might be a prominent vector of the toxin to higher trophic levels, including fishes, sea birds and even humans. In Portugal P. henslowii is commercialised during the summer in some local markets. DA concentrations were found close to the legal limit of 20 microg/g in samples purchased at Figueira da Foz market. The crabs are boiled prior to reaching the consumers. The cooking process was evaluated. Determination of toxin losses during the cooking process showed a toxin reduction higher than 50%. DA was determined by HPLC-UV and confirmed by spectra acquired with diode-array detector.

  20. Testing Phylogenetic Hypotheses of the Subgenera of the Freshwater Crayfish Genus Cambarus (Decapoda: Cambaridae)

    PubMed Central

    Breinholt, Jesse W.; Porter, Megan L.; Crandall, Keith A.

    2012-01-01

    Background The genus Cambarus is one of three most species rich crayfish genera in the Northern Hemisphere. The genus has its center of diversity in the Southern Appalachians of the United States and has been divided into 12 subgenera. Using Cambarus we test the correspondence of subgeneric designations based on morphology used in traditional crayfish taxonomy to the underlying evolutionary history for these crayfish. We further test for significant correlation and explanatory power of geographic distance, taxonomic model, and a habitat model to estimated phylogenetic distance with multiple variable regression. Methodology/Principal Findings We use three mitochondrial and one nuclear gene regions to estimate the phylogenetic relationships for species within the genus Cambarus and test evolutionary hypotheses of relationships and associated morphological and biogeographical hypotheses. Our resulting phylogeny indicates that the genus Cambarus is polyphyletic, however we fail to reject the monophyly of Cambarus with a topology test. The majority of the Cambarus subgenera are rejected as monophyletic, suggesting the morphological characters used to define those taxa are subject to convergent evolution. While we found incongruence between taxonomy and estimated phylogenetic relationships, a multiple model regression analysis indicates that taxonomy had more explanatory power of genetic relationships than either habitat or geographic distance. Conclusions We find convergent evolution has impacted the morphological features used to delimit Cambarus subgenera. Studies of the crayfish genus Orconectes have shown gonopod morphology used to delimit subgenera is also affected by convergent evolution. This suggests that morphological diagnoses based on traditional crayfish taxonomy might be confounded by convergent evolution across the cambarids and has little utility in diagnosing relationships or defining natural groups. We further suggest that convergent morphological evolution appears to be a common occurrence in invertebrates suggesting the need for careful phylogenetically based interpretations of morphological evolution in invertebrate systematics. PMID:23049950

  1. Phylogenetic relationships, character evolution, and taxonomic implications within the slipper lobsters (Crustacea: Decapoda: Scyllaridae).

    PubMed

    Yang, Chien-Hui; Bracken-Grissom, Heather; Kim, Dohyup; Crandall, Keith A; Chan, Tin-Yam

    2012-01-01

    The slipper lobsters belong to the family Scyllaridae which contains a total of 20 genera and 89 species distributed across four subfamilies (Arctidinae, Ibacinae, Scyllarinae, and Theninae). We have collected nucleotide sequence data from regions of five different genes (16S, 18S, COI, 28S, H3) to estimate phylogenetic relationships among 54 species from the Scyllaridae with a focus on the species rich subfamily Scyllarinae. We have included in our analyses at least one representative from all 20 genera in the Scyllaridae and 35 of the 52 species within the Scyllarinae. Our resulting phylogenetic estimate shows the subfamilies are monophyletic, except for Ibacinae, which has paraphyletic relationships among genera. Many of the genera within the Scyllarinae form non-monophyletic groups, while the genera from all other subfamilies form well supported clades. We discuss the implications of this history on the evolution of morphological characters and ecological transitions (nearshore vs. offshore) within the slipper lobsters. Finally, we identify, through ancestral state character reconstructions, key morphological features diagnostic of the major clades of diversity within the Scyllaridae and relate this character evolution to current taxonomy and classification. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Distribution, reproduction, and feeding of West African shrimp Plesionika carinata Holthuis, 1951 (Decapoda, Pandalidae)

    NASA Astrophysics Data System (ADS)

    Burukovsky, R. N.

    2017-09-01

    Plesionika carinata is endemic in the West African tropical biogeographical realm and is distributed from the western Sahara coast (23°35' N) to southern Namibia (29° S). A total of 263 individuals with a total carapace length of 31 to 71 mm have been studied. P. carinata juveniles are pelagic and occur over depths from 340 to 2000 m or more, mainly over the lower part of the continental slope in summer and over the upper part of the continental slope in autumn. Adults are mainly benthic and occur on the edge of the shelf and the upper part of the continental slope (at depths of 300 to 880 m). Ovigerous females have 750 to 3330 eggs 0.45-0.5 × 0.5-0.65 mm in size on pleopods. Plesionika carinata feeds on abundant micronectonic and macroplanktonic crustaceans (euphausiids and pelagic shrimps) at earlier pelagic stages; it is detritophagous/necrophagous and predatory near the bottom when adult.

  3. Evolutionary history of true crabs (Crustacea: Decapoda: Brachyura) and the origin of freshwater crabs.

    PubMed

    Tsang, Ling Ming; Schubart, Christoph D; Ahyong, Shane T; Lai, Joelle C Y; Au, Eugene Y C; Chan, Tin-Yam; Ng, Peter K L; Chu, Ka Hou

    2014-05-01

    Crabs of the infra-order Brachyura are one of the most diverse groups of crustaceans with approximately 7,000 described species in 98 families, occurring in marine, freshwater, and terrestrial habitats. The relationships among the brachyuran families are poorly understood due to the high morphological complexity of the group. Here, we reconstruct the most comprehensive phylogeny of Brachyura to date using sequence data of six nuclear protein-coding genes and two mitochondrial rRNA genes from more than 140 species belonging to 58 families. The gene tree confirms that the "Podotremata," are paraphyletic. Within the monophyletic Eubrachyura, the reciprocal monophyly of the two subsections, Heterotremata and Thoracotremata, is supported. Monophyly of many superfamilies, however, is not recovered, indicating the prevalence of morphological convergence and the need for further taxonomic studies. Freshwater crabs were derived early in the evolution of Eubrachyura and are shown to have at least two independent origins. Bayesian relaxed molecular methods estimate that freshwater crabs separated from their closest marine sister taxa ~135 Ma, that is, after the break up of Pangaea (∼200 Ma) and that a Gondwanan origin of these freshwater representatives is untenable. Most extant families and superfamilies arose during the late Cretaceous and early Tertiary.

  4. Conservation status of North American freshwater crayfish (Decapoda: Cambaridae) from the southern United States

    USGS Publications Warehouse

    Loughman, Zachary J.; Welsh, Stuart A.; Fetzner, James W.; Thoma, Roger F.

    2015-01-01

    A list is provided of all crayfishes (family Cambaridae) in the southern United States, which includes common names, global conservation status, an alternative review of the conservation status based on the IUCN red list criteria, and state distribution. This list includes 357 native crayfishes, of which 12 (3.4%) are critically endangered, 37 (10.4%) are endangered, 126 (35.3%) are vulnerable, 181 (50.7%) are lower risk, and 1 (0.3%) is not evaluated. The leading factors causing imperilment are restricted ranges caused by anthropogenic impacts from changes in land use, contaminants, invasion by non-indigenous species, and habitat fragmentation. In order to conserve and manage diversity of native crayfish, consistency is needed in determining conservation status and more complete distribution and life history information are needed for about 60% of species.

  5. Shrimps down under: evolutionary relationships of subterranean crustaceans from Western Australia (Decapoda: Atyidae: Stygiocaris).

    PubMed

    Page, Timothy J; Humphreys, William F; Hughes, Jane M

    2008-02-20

    We investigated the large and small scale evolutionary relationships of the endemic Western Australian subterranean shrimp genus Stygiocaris (Atyidae) using nuclear and mitochondrial genes. Stygiocaris is part of the unique cave biota of the coastal, anchialine, limestones of the Cape Range and Barrow Island, most of whose nearest evolutionary relations are found in coastal caves of the distant North Atlantic. The dominance of atyids in tropical waters and their food resources suggest they are pivotal in understanding these groundwater ecosystems. Our nuclear and mitochondrial analyses all recovered the Mexican cave genus Typhlatya as the sister taxon of Stygiocaris, rather than any of the numerous surface and cave atyids from Australia or the Indo-Pacific region. The two described Stygiocaris species were recovered as monophyletic, and a third, cryptic, species was discovered at a single site, which has very different physiochemical properties from the sites hosting the two described species. Our findings suggest that Stygiocaris and Typhlatya may descend from a common ancestor that lived in the coastal marine habitat of the ancient Tethys Sea, and were subsequently separated by plate tectonic movements. This vicariant process is commonly thought to explain the many disjunct anchialine faunas, but has rarely been demonstrated using phylogenetic techniques. The Cape Range's geological dynamism, which is probably responsible for the speciation of the various Stygiocaris species, has also led to geographic population structure within species. In particular, Stygiocaris lancifera is split into northern and southern groups, which correspond to population splits within other sympatric subterranean taxa.

  6. Evolution through cold and deep waters: the molecular phylogeny of the Lithodidae (Crustacea: Decapoda).

    PubMed

    Hall, Sally; Thatje, Sven

    2018-02-27

    The objectives of this work are to use gene sequence data to assess the hypothesis that the Lithodinae arose from ancestors with uncalcified abdomens in shallow waters of the North-East Pacific, investigate the monophyly and interrelationships of genera within the Lithodinae and to estimate the scale and minimum number of biogeographic transitions from the shallow environment to the deep sea and vice versa. To do this, phylogenetic analysis from three mitochondrial and three nuclear markers was conducted using minimum evolution, maximum likelihood and Bayesian methods. The Lithodinae as defined to include North Pacific genus Cryptolithodes may be paraphyletic, with the Hapalogastrinae and Cryptolithodes as sister taxa. This implies that the soft-bodied abdomen of the Hapalogastrinae might not be plesiomorphic for the Lithodidae. Paralomis, Lopholithodes, Phyllolithodes, Lithodes and Neolithodes share a common ancestor, from which the North Pacific Hapalogastrinae did not descend. Lithodid ancestors are likely to have had a north Pacific, shallow water distribution and to have had planktotrophic larvae. North Pacific genus Paralithodes is paraphyletic; P. brevipes is the most basal member of the genus (as sampled) while P. camtschaticus and P. platypus are more closely related to the genera Lithodes and Neolithodes. Genera Lithodes, Neolithodes and Paralomis (as sampled) are monophyletic if Glyptolithodes is included within Paralomis. Lopholithodes is closely related to, but not included within, the Paralomis genus. Paralomis is divided into at least two major lineages: one containing South Atlantic, West African, and Indian Ocean species, and the other containing Pacific and South American species. Several species of Paralomis do not resolve consistently with any other groups sampled, implying a complex and possibly rapid global evolution early in the history of the genus. Relationships within the Lithodes genus vary between analytical methods, suggesting that conclusions may not be stable. Consistently, however, Indian Ocean and Pacific forms-L. murrayi, L. longispina and L. nintokuae form a group separated from Atlantic species such as L. santolla, L. confundens, L. maja and L. ferox.

  7. Shrimps Down Under: Evolutionary Relationships of Subterranean Crustaceans from Western Australia (Decapoda: Atyidae: Stygiocaris)

    PubMed Central

    Page, Timothy J.; Humphreys, William F.; Hughes, Jane M.

    2008-01-01

    Background We investigated the large and small scale evolutionary relationships of the endemic Western Australian subterranean shrimp genus Stygiocaris (Atyidae) using nuclear and mitochondrial genes. Stygiocaris is part of the unique cave biota of the coastal, anchialine, limestones of the Cape Range and Barrow Island, most of whose nearest evolutionary relations are found in coastal caves of the distant North Atlantic. The dominance of atyids in tropical waters and their food resources suggest they are pivotal in understanding these groundwater ecosystems. Methodology/Principle Findings Our nuclear and mitochondrial analyses all recovered the Mexican cave genus Typhlatya as the sister taxon of Stygiocaris, rather than any of the numerous surface and cave atyids from Australia or the Indo-Pacific region. The two described Stygiocaris species were recovered as monophyletic, and a third, cryptic, species was discovered at a single site, which has very different physiochemical properties from the sites hosting the two described species. Conclusions/Significance Our findings suggest that Stygiocaris and Typhlatya may descend from a common ancestor that lived in the coastal marine habitat of the ancient Tethys Sea, and were subsequently separated by plate tectonic movements. This vicariant process is commonly thought to explain the many disjunct anchialine faunas, but has rarely been demonstrated using phylogenetic techniques. The Cape Range's geological dynamism, which is probably responsible for the speciation of the various Stygiocaris species, has also led to geographic population structure within species. In particular, Stygiocaris lancifera is split into northern and southern groups, which correspond to population splits within other sympatric subterranean taxa. PMID:18286175

  8. Thermal biology of the sub-polar-temperate estuarine crab Hemigrapsus crenulatus (Crustacea: Decapoda: Varunidae).

    PubMed

    Cumillaf, Juan P; Blanc, Johnny; Paschke, Kurt; Gebauer, Paulina; Díaz, Fernando; Re, Denisse; Chimal, María E; Vásquez, Jorge; Rosas, Carlos

    2016-02-15

    Optimum temperatures can be measured through aerobic scope, preferred temperatures or growth. A complete thermal window, including optimum, transition (Pejus) and critical temperatures (CT), can be described if preferred temperatures and CT are defined. The crustacean Hemigrapsus crenulatus was used as a model species to evaluate the effect of acclimation temperature on: (i) thermal preference and width of thermal window, (ii) respiratory metabolism, and (iii) haemolymph proteins. Dependant on acclimation temperature, preferred temperature was between 11.8°C and 25.2°C while CT was found between a minimum of 2.7°C (CTmin) and a maximum of 35.9°C (CTmax). These data and data from tropical and temperate crustaceans were compared to examine the association between environmental temperature and thermal tolerance. Temperate species have a CTmax limit around 35°C that corresponded with the low CTmax limit of tropical species (34-36°C). Tropical species showed a CTmin limit around 9°C similar to the maximum CTmin of temperate species (5-6°C). The maximum CTmin of deep sea species that occur in cold environments (2.5°C) matched the low CTmin values (3.2°C) of temperate species. Results also indicate that the energy required to activate the enzyme complex (Ei) involved in respiratory metabolism of ectotherms changes along the latitudinal gradient of temperature. © 2016. Published by The Company of Biologists Ltd.

  9. Thermal biology of the sub-polar–temperate estuarine crab Hemigrapsus crenulatus (Crustacea: Decapoda: Varunidae)

    PubMed Central

    Cumillaf, Juan P.; Blanc, Johnny; Paschke, Kurt; Gebauer, Paulina; Díaz, Fernando; Re, Denisse; Chimal, María E.; Vásquez, Jorge; Rosas, Carlos

    2016-01-01

    ABSTRACT Optimum temperatures can be measured through aerobic scope, preferred temperatures or growth. A complete thermal window, including optimum, transition (Pejus) and critical temperatures (CT), can be described if preferred temperatures and CT are defined. The crustacean Hemigrapsus crenulatus was used as a model species to evaluate the effect of acclimation temperature on: (i) thermal preference and width of thermal window, (ii) respiratory metabolism, and (iii) haemolymph proteins. Dependant on acclimation temperature, preferred temperature was between 11.8°C and 25.2°C while CT was found between a minimum of 2.7°C (CTmin) and a maximum of 35.9°C (CTmax). These data and data from tropical and temperate crustaceans were compared to examine the association between environmental temperature and thermal tolerance. Temperate species have a CTmax limit around 35°C that corresponded with the low CTmax limit of tropical species (34–36°C). Tropical species showed a CTmin limit around 9°C similar to the maximum CTmin of temperate species (5–6°C). The maximum CTmin of deep sea species that occur in cold environments (2.5°C) matched the low CTmin values (3.2°C) of temperate species. Results also indicate that the energy required to activate the enzyme complex (Ei) involved in respiratory metabolism of ectotherms changes along the latitudinal gradient of temperature. PMID:26879464

  10. Agonistic behaviour in juvenile southern rock lobster, Jasusedwardsii (Decapoda, Palinuridae): implications for developing aquaculture.

    PubMed

    Carter, Chris G; Westbury, Heath; Crear, Bradley; Simon, Cedric; Thomas, Craig

    2014-01-01

    The Southern rock lobster, Jasusedwardsii, is a temperate species of spiny lobster with established well managed fisheries in Australia and New Zealand. It has also been under consideration as a species with aquaculture potential. Agonistic behaviour has important consequences under aquaculture conditions that encompass direct effects, such as damage or death of protagonists, and indirect effects on growth that relate to resource access, principally food and refuge. This study aimed to identify and characterize behaviours and to make a preliminary investigation of their occurrence under tank culture. Juvenile Jasusedwardsii were examined in a flow-through seawater system using a remote video camera system. Twenty-nine behaviours were divided into three sub-groups: aggressive (11), avoidance (6) and others (12). Aggressive behaviours included attacks, pushing, lifting, clasping and carrying an opponent. Avoidance behaviours included moving away in a backwards-, forwards- or side-stepping motion as well as with more vigorous tail flips. These behaviours were components of twelve behavioural groups that described contact, attack and displacement between individuals. Activity was crepuscular with two clear peaks, one in the morning and the other in the evening. The occurrence of behavioural groups was not different between the morning and evening. The frequency of aggressive behaviours was not affected by changes made to stocking density or access to food. The implications of agonistic behaviours are discussed further in relation to developing aquaculture.

  11. Evolution through cold and deep waters: the molecular phylogeny of the Lithodidae (Crustacea: Decapoda)

    NASA Astrophysics Data System (ADS)

    Hall, Sally; Thatje, Sven

    2018-04-01

    The objectives of this work are to use gene sequence data to assess the hypothesis that the Lithodinae arose from ancestors with uncalcified abdomens in shallow waters of the North-East Pacific, investigate the monophyly and interrelationships of genera within the Lithodinae and to estimate the scale and minimum number of biogeographic transitions from the shallow environment to the deep sea and vice versa. To do this, phylogenetic analysis from three mitochondrial and three nuclear markers was conducted using minimum evolution, maximum likelihood and Bayesian methods. The Lithodinae as defined to include North Pacific genus Cryptolithodes may be paraphyletic, with the Hapalogastrinae and Cryptolithodes as sister taxa. This implies that the soft-bodied abdomen of the Hapalogastrinae might not be plesiomorphic for the Lithodidae. Paralomis, Lopholithodes, Phyllolithodes, Lithodes and Neolithodes share a common ancestor, from which the North Pacific Hapalogastrinae did not descend. Lithodid ancestors are likely to have had a north Pacific, shallow water distribution and to have had planktotrophic larvae. North Pacific genus Paralithodes is paraphyletic; P. brevipes is the most basal member of the genus (as sampled) while P. camtschaticus and P. platypus are more closely related to the genera Lithodes and Neolithodes. Genera Lithodes, Neolithodes and Paralomis (as sampled) are monophyletic if Glyptolithodes is included within Paralomis. Lopholithodes is closely related to, but not included within, the Paralomis genus. Paralomis is divided into at least two major lineages: one containing South Atlantic, West African, and Indian Ocean species, and the other containing Pacific and South American species. Several species of Paralomis do not resolve consistently with any other groups sampled, implying a complex and possibly rapid global evolution early in the history of the genus. Relationships within the Lithodes genus vary between analytical methods, suggesting that conclusions may not be stable. Consistently, however, Indian Ocean and Pacific forms— L. murrayi, L. longispina and L. nintokuae form a group separated from Atlantic species such as L. santolla, L. confundens, L. maja and L. ferox.

  12. Purification and characterization of a lectin from the white shrimp Litopenaeus setiferus (Crustacea decapoda) hemolymph.

    PubMed

    Alpuche, Juan; Pereyra, Ali; Agundis, Concepción; Rosas, Carlos; Pascual, Cristina; Slomianny, Marie-Christine; Vázquez, Lorena; Zenteno, Edgar

    2005-06-20

    A 291-kDa lectin (LsL) was purified from the hemolymph of the white shrimp Litopenaeus setiferus by affinity chromatography on glutaraldehyde-fixed stroma from rabbit erythrocytes. LsL is a heterotetramer of two 80-kDa and two 52-kDa subunits, with no covalently-liked carbohydrate, and mainly composed by aspartic and glutamic acids, glycine and alanine, with relatively lower methionine and cysteine contents. Edman degradation indicated that the NH2-terminal of the 80-kDa subunit is composed DASNAQKQHDVNFLL, whereas the NH2-terminal of the 52-kDa subunit is blocked. The peptide mass fingerprint of LsL was predicted from tryptic peptides from each subunit by MALDI-TOF, and revealed that each subunit showed 23 and 22%, respectively, homology with the hemocyanin precursor from Litopenaeus vannamei. Circular dichroism analysis revealed beta sheet and alpha helix contents of 52.7 and 6.1%, respectively. LsL agglutinate at higher titers guinea pig, murine, and rabbit erythrocytes its activity is divalent cation-dependent. N-acetylated sugars, such as GlcNAc, GalNAc, and NeuAc, were the most effective inhibitors of the LsL hemagglutinating activity. Sialylated O-glycosylated proteins, such as bovine submaxillary gland mucin, human IgA, and fetuin, showed stronger inhibitory activity than sialylated N-glycosylated proteins, such as human orosomucoid, IgG, transferrin, and lactoferrin. Desialylation of erythrocytes or inhibitory glycoproteins abolished their capacity to bind LsL, confirming the relevance of sialic acid in LsL-ligand interactions.

  13. Digestive proteinases of red shrimp Pleoticus muelleri (Decapoda, Penaeoidea): partial characterization and relationship with molting.

    PubMed

    Fernández Gimenez, A V; García-Carreño, F L; Navarrete del Toro, M A; Fenucci, J L

    2001-10-01

    The present study describes the activity and some characteristics of proteinases in the hepatopancreas of red shrimp Pleoticus muelleri during the different stages of the molting cycle. Proteolytic activity was highest between pH 7.5 and 8. The hepatopancreatic protein content in the premolt stage was higher than in the other stages of the molting cycle (P<0.05). No significant differences were found in total proteolytic activity in the hepatopancreas when comparing molting stages. The proteolytic activity of the P. muelleri hepatopancreas enzyme preparations is the main responsibility of serine proteinases. TLCK, a trypsin inhibitor, reduced azocasein hydrolysis between 26% (intermolt) and 37% (premolt). TPCK, a chymotrypsin inhibitor, did not decrease hydrolytic activity, except for in postmolt. Low trypsin and chymotrypsin activities were found during intermolt, and increased in postmolt. The electrophoretogram of the enzyme extracts shows 12 bands of activity during intermolt (from 16.6 to 53.1 kDa). Some fractions were not detected in the postmolt and premolt stages. Three low molecular weight trypsin forms (17.4, 19.1 and 20 kDa) were found in all molting stages. One band of chymotrypsin (21.9 kDa) was observed in all molting stages. High molecular mass active bands (66-205 kDa) could not be characterized with inhibitors. Comparison of the protease-specific activity of the hepatopancreas of some species indicated a relationship between digestive enzyme activity and feeding habits of the shrimp. Omnivorous shrimp, such as Penaeus vannamei (syn: Litopenaeus vannamei) and Penaeus monodon, showed higher protease activity than the carnivorous shrimp, Penaeus californiensis (syn: Farfantepenaeus californiensis) and P. muelleri. In fact, the enzymatic activity in the hepatopancreas of P. muelleri showed variations in relation to feeding habit and molting cycle.

  14. Larval descriptions of the family Porcellanidae: A worldwide annotated compilation of the literature (Crustacea, Decapoda)

    PubMed Central

    Vela, María José; González-Gordillo, Juan Ignacio

    2016-01-01

    Abstract For most of the family Porcellanidae, which comprises 283 species, larval development remains to be described. Full development has been only described for 52 species, while part of the larval cycle has been described for 45 species. The importance of knowing the complete larval development of a species goes beyond allowing the identification of larval specimens collected in the plankton. Morphological larval data also constitute a support to cladistic techniques used in the establishment of the phylogenetic status (see Hiller et al. 2006, Marco-Herrero et al. 2013). Nevertheless, the literature on the larval development of this family is old and widely dispersed and in many cases it is difficult to collect the available information on a particular taxon. Towards the aim of facilitating future research, all information available on the larval development of porcellanids has been compiled. Following the taxonomic checklist of Porcellanidae proposed by Osawa and McLaughlin (2010), a checklist has been prepared that reflects the current knowledge about larval development of the group including larval stages and the method used to obtain the larvae, together with references. Those species for which the recognised names have been changed according to Osawa and McLaughlin (2010) are indicated. PMID:27081332

  15. Redescription of the early larval stages of the pandalid shrimp Chlorotocus crassicornis (Decapoda: Caridea: Pandalidae).

    PubMed

    Landeira, Jose M; Jiang, Guo-Chen; Chan, Tin-Yam; Shih, Tung-Wei; Gozález-Gordillo, J Ignacio

    2015-09-07

    The first four larval stages of the pandalid shrimp Chlorotocus crassicornis (A. Costa, 1871) are described and illustrated from laboratory-reared material obtained from ovigerous females collected in the southwestern Spain and south Taiwan. The second to fourth larval stages of this species are reported for the first time to science. Detailed examination of the first larval stages reveals that previous description misidentified some key larval characters which have prevented its identification in plankton samples. It is found that the zoeal morphology of Chlorotocus is not very different from other pandalid larvae, and in fact closely resembles Plesionika and Heterocarpus.

  16. Reproductive biology of galatheoid and chirostyloid (Crustacea: Decapoda) squat lobsters from the Gulf of Mexico.

    PubMed

    Kilgour, Morgan J; Shirley, Thomas C

    2014-01-16

    Reproductive timing, fecundity, and average egg sizes were examined for galatheoid and chirostyloid squat lobster collections from the Gulf of Mexico. While congeners did not always significantly differ in egg size or timing, each genus had a unique average egg diameter size which may indicate whether the developing embryos will be lecithotrophic or planktotrophic larvae. The eggs of Eumunididae, Galatheidae, and Munididae were more numerous and smaller than the larger and less abundant eggs of Chirostylidae and Munidopsidae. With the exception of members of the Munididae, members of genera within the same family had distinct egg diameters. Ovigerous females were significantly larger than non-ovigerous females in some species (i.e., Uroptychus nitidus, Munida forceps, Galacantha spinosa, Munidopsis abbreviata, M. alaminos, M., erinacea, M. robusta, M. sigsbei, and M. simplex). Munidopsis erinacea and Munida affinis males were significantly larger than females; the reverse was true for Munidopsis robusta and Munidopsis simplex. All other species studied did not have a significant difference between males and females. The spatial and bathymetric ranges for many species are extended in this study from prior reports. Seasonality of reproduction was evident in few species, but this may be a result of limited sample sizes.

  17. Differences in life-history and ecological traits between co-occurring Panulirus spiny lobsters (Decapoda, Palinuridae)

    PubMed Central

    Briones-Fourzán, Patricia

    2014-01-01

    Abstract Coexistence of closely related species may be promoted by niche differentiation or result from interspecific trade-offs in life history and ecological traits that influence relative fitness differences and contribute to competitive inequalities. Although insufficient to prove coexistence, trait comparisons provide a first step to identify functional differences between co-occurring congeneric species in relation to mechanisms of coexistence. Here, a comparative review on life history and ecological traits is presented for two pairs of co-occurring species of spiny lobsters in the genus Panulirus: Panulirus gracilis and Panulirus inflatus from the Eastern Central Pacific region, and Panulirus argus and Panulirus guttatus from the Caribbean region. Panulirus gracilis and Panulirus inflatus have similar larval, postlarval, and adult sizes and a similar diet, but differ in degree of habitat specialization, fecundity, and growth rate. However, little is known on behavioral traits of these two species that may influence their competitive abilities and susceptibility to predators. The more abundant information on Panulirus argus and Panulirus guttatus shows that these two species differ more broadly in degree of habitat specialization, larval, postlarval and adult sizes, diet, fecundity, growth rate, degree of sociality, defense mechanisms, susceptibility to predators, and chemical ecology, suggesting a greater degree of niche differentiation between Panulirus argus and Panulirus guttatus than between Panulirus gracilis and Panulirus inflatus. Whether the substantial niche differentiation and apparent interspecific trade-offs between Panulirus argus and Panulirus guttatus relative to Panulirus gracilis and Panulirus inflatus reflect an earlier divergence of the former pair of species in the evolution of the genus constitutes an intriguing hypothesis. However, whether or not post-divergence evolution of each species pair occurred in sympatry remains uncertain. PMID:25561843

  18. Differences in life-history and ecological traits between co-occurring Panulirus spiny lobsters (Decapoda, Palinuridae).

    PubMed

    Briones-Fourzán, Patricia

    2014-01-01

    Coexistence of closely related species may be promoted by niche differentiation or result from interspecific trade-offs in life history and ecological traits that influence relative fitness differences and contribute to competitive inequalities. Although insufficient to prove coexistence, trait comparisons provide a first step to identify functional differences between co-occurring congeneric species in relation to mechanisms of coexistence. Here, a comparative review on life history and ecological traits is presented for two pairs of co-occurring species of spiny lobsters in the genus Panulirus: Panulirusgracilis and Panulirusinflatus from the Eastern Central Pacific region, and Panulirusargus and Panulirusguttatus from the Caribbean region. Panulirusgracilis and Panulirusinflatus have similar larval, postlarval, and adult sizes and a similar diet, but differ in degree of habitat specialization, fecundity, and growth rate. However, little is known on behavioral traits of these two species that may influence their competitive abilities and susceptibility to predators. The more abundant information on Panulirusargus and Panulirusguttatus shows that these two species differ more broadly in degree of habitat specialization, larval, postlarval and adult sizes, diet, fecundity, growth rate, degree of sociality, defense mechanisms, susceptibility to predators, and chemical ecology, suggesting a greater degree of niche differentiation between Panulirusargus and Panulirusguttatus than between Panulirusgracilis and Panulirusinflatus. Whether the substantial niche differentiation and apparent interspecific trade-offs between Panulirusargus and Panulirusguttatus relative to Panulirusgracilis and Panulirusinflatus reflect an earlier divergence of the former pair of species in the evolution of the genus constitutes an intriguing hypothesis. However, whether or not post-divergence evolution of each species pair occurred in sympatry remains uncertain.

  19. Effects of Late-Cenozoic Glaciation on Habitat Availability in Antarctic Benthic Shrimps (Crustacea: Decapoda: Caridea)

    PubMed Central

    Dambach, Johannes; Thatje, Sven; Rödder, Dennis; Basher, Zeenatul; Raupach, Michael J.

    2012-01-01

    Marine invertebrates inhabiting the high Antarctic continental shelves are challenged by disturbance of the seafloor by grounded ice, low but stable water temperatures and variable food availability in response to seasonal sea-ice cover. Though a high diversity of life has successfully adapted to such conditions, it is generally agreed that during the Last Glacial Maximum (LGM) the large-scale cover of the Southern Ocean by multi-annual sea ice and the advance of the continental ice sheets across the shelf faced life with conditions, exceeding those seen today by an order of magnitude. Conditions prevailing at the LGM may have therefore acted as a bottleneck event to both the ecology as well as genetic diversity of today's fauna. Here, we use for the first time specific Species Distribution Models (SDMs) for marine arthropods of the Southern Ocean to assess effects of habitat contraction during the LGM on the three most common benthic caridean shrimp species that exhibit a strong depth zonation on the Antarctic continental shelf. While the shallow-water species Chorismus antarcticus and Notocrangon antarcticus were limited to a drastically reduced habitat during the LGM, the deep-water shrimp Nematocarcinus lanceopes found refuge in the Southern Ocean deep sea. The modeling results are in accordance with genetic diversity patterns available for C. antarcticus and N. lanceopes and support the hypothesis that habitat contraction at the LGM resulted in a loss of genetic diversity in shallow water benthos. PMID:23029463

  20. Effects of late-cenozoic glaciation on habitat availability in Antarctic benthic shrimps (Crustacea: Decapoda: Caridea).

    PubMed

    Dambach, Johannes; Thatje, Sven; Rödder, Dennis; Basher, Zeenatul; Raupach, Michael J

    2012-01-01

    Marine invertebrates inhabiting the high Antarctic continental shelves are challenged by disturbance of the seafloor by grounded ice, low but stable water temperatures and variable food availability in response to seasonal sea-ice cover. Though a high diversity of life has successfully adapted to such conditions, it is generally agreed that during the Last Glacial Maximum (LGM) the large-scale cover of the Southern Ocean by multi-annual sea ice and the advance of the continental ice sheets across the shelf faced life with conditions, exceeding those seen today by an order of magnitude. Conditions prevailing at the LGM may have therefore acted as a bottleneck event to both the ecology as well as genetic diversity of today's fauna. Here, we use for the first time specific Species Distribution Models (SDMs) for marine arthropods of the Southern Ocean to assess effects of habitat contraction during the LGM on the three most common benthic caridean shrimp species that exhibit a strong depth zonation on the Antarctic continental shelf. While the shallow-water species Chorismus antarcticus and Notocrangon antarcticus were limited to a drastically reduced habitat during the LGM, the deep-water shrimp Nematocarcinus lanceopes found refuge in the Southern Ocean deep sea. The modeling results are in accordance with genetic diversity patterns available for C. antarcticus and N. lanceopes and support the hypothesis that habitat contraction at the LGM resulted in a loss of genetic diversity in shallow water benthos.

  1. From the Palaeontological Collection of the Universalmuseum Joanneum - The Cenozoic Decapod Crustaceans (Crustacea: Malacostraca: Decapoda).

    PubMed

    Hyžný, Matúš; Gross, Martin

    2016-01-01

    Cenozoic decapod crustaceans housed in the collections of the Universalmuseum Joanneum (Graz, Austria) are reviewed. Previous descriptions, geographic and stratigraphic provenance and collection history are discussed. Altogether 72 specimens are figured, including five holotypes. Taxonomic affinity of previously unpublished material is addressed. Gebiacantha sp. from the middle Miocene of Wetzelsdorf is the first fossil record of the genus from the Paratethys.

  2. [In life determination of the physiological status of decapod crustaceans (Crustacea: Decapoda) by hematological characteristics].

    PubMed

    Aleksandrova, E N; Kovacheva, N P

    2010-01-01

    The application of hematological analysis techniques to detecting the physiological status of the economically valued decapods during their culturing, and in monitoring of the condition of their natural populations, is restrained by the incomplete knowledge of these invertebrates circulatory system and its properties. Scarce data on the use of hematological indicators for determining the physiological status of decapods may be found sporadically in published sources; there is shortage of basic standards needed for interpretation of the analytical results. In this regard the paper considers some data on the major properties of hemolymph and its cellular elements; on methods of their examination; and on the results of application of hematological characteristics to assessing the physiological condition of various species of decapods. The hematological indicators suitable for the analysis of live decapods include: time of coagulation and buffer characteristic of hemolymph; concentration of total proteins, copper, calcium, glucose and lactates in it; total number of hemocytes with the consideration of granulocytes share.

  3. Diversity and distribution of Chirostyloidea and Galatheoidea (Decapoda, Anomura) in the Southern Gulf of Mexico

    PubMed Central

    Vázquez-Bader, Ana Rosa; Gracia, Adolfo

    2016-01-01

    Abstract We examined the diversity, abundance, distribution, and average size of squat lobsters collected during eight cruises conducted on the continental shelf and slope of the Gulf of Mexico (Mexican/USA border to the Caribbean Sea). Six species belonging to two genera of Chirostyloidea, and 25 species of four genera of Galatheoidea are reported. A total of 1513 specimens were obtained of which 95 were Chirostylidae, two Galatheidae, 285 Munidopsidae, and 1131 Munididae. Of the species collected, 13.8% were only known from Caribbean Sea. Three species of Chirostylidae—Gastroptychus salvadori, Uroptychus capillatus, and Uroptychus spiniger—as well two of Munidopsidae, Munidopsis bradleyi and Munidopsis riveroi, are recorded for the first time in the Gulf of Mexico. The upper bathymetric range of one species and the lower one for eight species are extended. Biological and ecological traits of squat lobsters in the southern Gulf of Mexico are also provided. PMID:27667921

  4. Diversity and distribution of Chirostyloidea and Galatheoidea (Decapoda, Anomura) in the Southern Gulf of Mexico.

    PubMed

    Vázquez-Bader, Ana Rosa; Gracia, Adolfo

    2016-01-01

    We examined the diversity, abundance, distribution, and average size of squat lobsters collected during eight cruises conducted on the continental shelf and slope of the Gulf of Mexico (Mexican/USA border to the Caribbean Sea). Six species belonging to two genera of Chirostyloidea, and 25 species of four genera of Galatheoidea are reported. A total of 1513 specimens were obtained of which 95 were Chirostylidae, two Galatheidae, 285 Munidopsidae, and 1131 Munididae. Of the species collected, 13.8% were only known from Caribbean Sea. Three species of Chirostylidae-Gastroptychus salvadori, Uroptychus capillatus, and Uroptychus spiniger-as well two of Munidopsidae, Munidopsis bradleyi and Munidopsis riveroi, are recorded for the first time in the Gulf of Mexico. The upper bathymetric range of one species and the lower one for eight species are extended. Biological and ecological traits of squat lobsters in the southern Gulf of Mexico are also provided.

  5. Nervous systems in 3D: a comparison of Caridean, anomuran, and brachyuran zoea-I (Decapoda).

    PubMed

    Geiselbrecht, Hannes; Melzer, Roland R

    2013-12-01

    Using serial semi-thin sections and digital 3D-reconstructions we studied the nervous systems of zoea-I larvae in three decapod species, Hippolyte inermis (Leach, 1815), Porcellana platycheles (Pennant, 1777), and Pachygrapsus marmoratus (Fabricius, 1787). These taxa represent three decapod lineages, that is, Caridea, Anomura, and Brachyura, each characterized by specific zoea-I morphology. Special attention was paid to development of ganglia, neuropil composition, and segmental nerves. In all zoeae studied, the overall elements, for example, the segmental ganglia, their neuropils and most of the nerves of the adult decapod nervous system are present. Ongoing differentiation processes are observable as well, most obvious in segments with well-developed limbs the ganglia are in a more advanced stage of differentiation and more voluminous compared to segments with only limb buds or without externally visible limb anlagen. Intra- and interspecific comparisons indicate that neuromere differentiation thus deviates from a simple anterior-posterior gradient as, for example, posterior thoracic neuromeres are less developed than those of the pleon. In addition, the differences in the progress of the development of ganglia between the studied taxa can best be attributed to heterochronic mechanisms. Taxon and stage-specific morphologies indicate that neuronal architecture reflects both, morphogenesis to the adult stage and specific larval adaptions, and provides sets of characters relevant to understanding the corresponding phylogeny. © 2013 Wiley Periodicals, Inc.

  6. Callianassa ehsani, a new species of Callianassidae (Crustacea, Decapoda, Axiidea) from Gulf of Oman, Iran.

    PubMed

    Sepahvand, Vahid; Tudge, Christopher; Momtazi, Farzaneh

    2018-04-17

    Callianassa ehsani sp. nov. is described as a new species from the Gulf of Oman, Iran. It differs from all other members of the subfamily Callianassinae in having a well-developed meral hook on the merus and 6 or 7 acute spines on the ischium of the large cheliped and characters of the small cheliped and telson. This new species is most similar to Callianassa thailandica Sakai, 2005 and Callianassa persica, Sakai, 2005. The generic assignment of the new species is provisional, reflecting the unstable state of the taxonomy of this family.

  7. Reproductive biology of the prawn Melicertus kerathurus (Decapoda: Penaeidae) in Thermaikos Gulf (N. Aegean Sea)

    NASA Astrophysics Data System (ADS)

    Kevrekidis, Kosmas; Thessalou-Legaki, Maria

    2013-03-01

    The reproductive biology including insemination frequency, ovarian maturation, gonadosomatic index (GSI), size at first maturity, and fecundity of Melicertus kerathurus were investigated using monthly samples from Thermaikos Gulf. Insemination was recorded by the presence of a spermatophore in the thelycum, and ovarian development was based on macroscopic ovarian staging (ST1-ST5). Inseminated females were found throughout the year with high percentages recorded from April to July. Although all ovarian stages were represented in mated females, insemination increased with size and ovarian maturation. High percentages of vitellogenic or mature ovarian stages were observed from May to July, while immature and developing ovaries were predominant mainly in winter. Spawned ovaries occurred from May to October. Carapace length at first maturity based on the presence of a spermatophore (CL50sp) was estimated at 39.20 mm, while that based on the presence of vitellogenic and mature ovaries (CL50ov) at 40.70 mm. The seasonal peak in the proportion of mature females (ST4) varied with size. Inseminated females at ST4 and GSI peaked in June-July. GSI varied in relation to insemination status and ovarian stage. In large females (>50 mm CL), the decline in mature ovaries and GSI increment with size indicates a relative reduction in the reproductive output. The number of oocytes ranged from 62,742 to 602,947 (mean ± SD: 268,000 ± 113,000). As the prawns are targeted during the spawning season, mainly by the artisanal fishery, and female size at first maturity is selected by artisanal net size, managerial measures toward artisanal fishery should be implemented.

  8. Niche partitioning of feeding microhabitats produces a unique function for herbivorous rabbitfishes (Perciformes, Siganidae) on coral reefs

    NASA Astrophysics Data System (ADS)

    Fox, R. J.; Bellwood, D. R.

    2013-03-01

    Niche theory predicts that coexisting species minimise competition by evolving morphological or behavioural specialisations that allow them to spread out along resource axes such as space, diet and temporal activity. These specialisations define how a species interacts with its environment and, by extension, determine its functional role. Here, we examine the feeding niche of three species of coral reef-dwelling rabbitfishes (Siganidae, Siganus). By comparing aspects of their feeding behaviour (bite location, bite rate, foraging distance) with that of representative species from two other abundant herbivorous fish families, the parrotfishes (Labridae, Scarus) and surgeonfishes (Acanthuridae, Acanthurus), we examine whether rabbitfishes have a feeding niche distinct from other members of the herbivore guild. Measurements of the penetration of the fishes' snouts and bodies into reef concavities when feeding revealed that rabbitfish fed to a greater degree from reef crevices and interstices than other herbivores. There was just a 40 % overlap in the penetration-depth niche between rabbitfish and surgeonfish and a 45 % overlap between rabbitfish and parrotfish, compared with the almost complete niche overlap (95 %) recorded for parrotfish and surgeonfish along this spatial niche axis. Aspects of the morphology of rabbitfish which may contribute to this niche segregation include a comparatively longer, narrower snout and narrower head. Our results suggest that sympatric coexistence of rabbitfish and other reef herbivores is facilitated by segregation along a spatial (and potentially dietary) axis. This segregation results in a unique functional role for rabbitfishes among roving herbivores that of "crevice-browser": a group that specifically feeds on crevice-dwelling algal or benthic organisms. This functional trait may have implications for reef ecosystem processes in terms of controlling the successional development of crevice-based algal communities, reducing their

  9. Altered juvenile fish communities associated with invasive Halophila stipulacea seagrass habitats in the U.S. Virgin Islands.

    PubMed

    Olinger, Lauren K; Heidmann, Sarah L; Durdall, Allie N; Howe, Colin; Ramseyer, Tanya; Thomas, Sara G; Lasseigne, Danielle N; Brown, Elizabeth J; Cassell, John S; Donihe, Michele M; Duffing Romero, Mareike D; Duke, Mara A; Green, Damon; Hillbrand, Paul; Wilson Grimes, Kristin R; Nemeth, Richard S; Smith, Tyler B; Brandt, Marilyn

    2017-01-01

    Caribbean seagrass habitats provide food and protection for reef-associated juvenile fish. The invasive seagrass Halophila stipulacea is rapidly altering these seascapes. Since its arrival in the Caribbean in 2002, H. stipulacea has colonized and displaced native seagrasses, but the function of this invasive seagrass as a juvenile fish habitat remains unknown. To compare diversity, community structure, and abundance of juvenile fish between H. stipulacea and native seagrass beds, fish traps were deployed in four nearshore bays around St. Thomas, U.S. Virgin Islands. Traps were deployed in Frenchman, Lindbergh, and Sprat Bays for 24 h intervals in patches of bare sand, patches of H. stipulacea and patches of the native Caribbean seagrasses Thalassia testudinum and Syringodium filiforme. Traps were then deployed in Brewers Bay for 12 h intervals in stands of H. stipulacea and S. filiforme. Relative and total abundances of juvenile fish, identified at least to family, were compared across treatment habitats for each trap deployment period. The catch from H. stipulacea, compared to native seagrasses, comprised a greater abundance of nocturnal carnivores Lutjanus synagris (family Lutjanidae) and Haemulon flavolineatum (family Haemulidae). Additionally, the herbivore species Sparisoma aurofrenatum (family Labridae) and Acanthurus bahianus (family Acanthuridae) and the diurnal carnivore species Pseudopeneus maculatus (family Mullidae) were relatively scarce in H. stipulacea. The catch from sand was much smaller, compared to vegetated habitats, and comprised only L. synagris, H. flavolineatum, and H. aurolineatum. These results provide evidence of reduced family diversity and altered juvenile fish assemblages in H. stipulacea, driven by an abundance of some nocturnal carnivores and scarcity of herbivores and diurnal carnivores. The findings from the present work underpin the need for further investigation and mitigation of this invasion, particularly where H. stipulacea is

  10. Isolation by distance and vicariance drive genetic structure of a coral reef fish in the Pacific Ocean.

    PubMed

    Planes, S; Fauvelot, C

    2002-02-01

    We studied the genetic diversity of a coral reef fish species to investigate the origin of the differentiation. A total of 727 Acanthurus triostegus collected from 15 locations throughout the Pacific were analyzed for 20 polymorphic loci. The genetic structure showed limited internal disequilibrium within each population; 3.7% of the loci showed significant Hardy-Weinberg disequilibrium, mostly associated with Adh*, and we subsequently removed this locus from further analysis of geographic pattern. The genetic structure of A. triostegus throughout the tropical Pacific Ocean revealed a strong geographic pattern. Overall, there was significant population differentiation (multilocus F(ST) = 0.199), which was geographically structured according to bootstraps of neighbor-joining analysis on Nei's unbiased genetic distances and AMOVA analysis. The genetic structure revealed five geographic groups in the Pacific Ocean: western Pacific (Guam, Philippines, Palau, and Great Barrier Reef); central Pacific (Solomons, New Caledonia, and Fiji); and three groups made up of the eastern populations, namely Hawaiian Archipelago (north), Marquesas (equatorial), and southern French Polynesia (south) that incorporates Clipperton Island located in the northeastern Pacific. In addition, heterozygosity values were found to be geographically structured with higher values grouped within Polynesian and Clipperton populations, which exhibited lower population size. Finally, the genetic differentiation (F(ST)) was significantly correlated with geographic distance when populations from the Hawaiian and Marquesas archipelagos were separated from all the other locations. These results show that patterns of differentiation vary within the same species according to the spatial scale, with one group probably issued from vicariance, whereas the other followed a pattern of isolation by distance. The geographic pattern for A. triostegus emphasizes the diversity of the evolutionary processes that lead

  11. Dual Roles of an Algal Farming Damselfish as a Cultivator and Opportunistic Browser of an Invasive Seaweed

    PubMed Central

    Peyton, Kimberly A.; Valentino, Lauren M.; Maruska, Karen P.

    2014-01-01

    Herbivory is a fundamental process determining reef resilience, and while algal farming damselfishes can help shape benthic assemblages, an understanding of their contribution to areas outside of defended territories is relatively unexplored. Here, we demonstrate how the farming damselfish Stegastes marginatus plays a dual role in benthic structuring by 1) contributing to persistence of the invasive macroalga Acanthophora spicifera within a Hawaiian marine protected area, where the macroalga occurred exclusively inside Stegastes territories, and 2) behaving as an opportunistic browser of the exotic alga outside their territorial borders. Greater than 50% of the biomass of tethered A. spicifera was consumed within one-hour when placed outside Stegastes territories, compared to <5% lost from tethers within territories or herbivore exclusion cages. In situ remote video revealed that tethered A. spicifera located outside territories was grazed primarily by the surgeonfish Acanthurus nigrofuscus (∼68% of total bites) and, surprisingly, by S. marginatus (∼27% of total bites) that left their territories to feed on this resource on 107 occasions during 400 min of filming. Further, for over half of those occurrences where S. marginatus grazed on the tethered macroalga outside of territories, they fed alongside conspecifics and other species, displaying little of the aggressiveness that characterizes this damselfish. These results show that S. marginatus plays a wider role in determining benthic assemblages than previously recognized, acting both as cultivators of a canopy-forming invasive macroalga within their territories, and as opportunistic browsers in neighboring sites. Consequently, S. marginatus can affect benthic species composition across their territory borders. These results provide a rare example of interspecific facilitation of an exotic alga by an indigenous marine fish. Accounting for fish behaviors more broadly is important to further our understanding

  12. Altered juvenile fish communities associated with invasive Halophila stipulacea seagrass habitats in the U.S. Virgin Islands

    PubMed Central

    Brown, Elizabeth J.; Cassell, John S.; Donihe, Michele M.; Duffing Romero, Mareike D.; Duke, Mara A.; Green, Damon; Hillbrand, Paul; Wilson Grimes, Kristin R.; Nemeth, Richard S.; Smith, Tyler B.; Brandt, Marilyn

    2017-01-01

    Caribbean seagrass habitats provide food and protection for reef-associated juvenile fish. The invasive seagrass Halophila stipulacea is rapidly altering these seascapes. Since its arrival in the Caribbean in 2002, H. stipulacea has colonized and displaced native seagrasses, but the function of this invasive seagrass as a juvenile fish habitat remains unknown. To compare diversity, community structure, and abundance of juvenile fish between H. stipulacea and native seagrass beds, fish traps were deployed in four nearshore bays around St. Thomas, U.S. Virgin Islands. Traps were deployed in Frenchman, Lindbergh, and Sprat Bays for 24 h intervals in patches of bare sand, patches of H. stipulacea and patches of the native Caribbean seagrasses Thalassia testudinum and Syringodium filiforme. Traps were then deployed in Brewers Bay for 12 h intervals in stands of H. stipulacea and S. filiforme. Relative and total abundances of juvenile fish, identified at least to family, were compared across treatment habitats for each trap deployment period. The catch from H. stipulacea, compared to native seagrasses, comprised a greater abundance of nocturnal carnivores Lutjanus synagris (family Lutjanidae) and Haemulon flavolineatum (family Haemulidae). Additionally, the herbivore species Sparisoma aurofrenatum (family Labridae) and Acanthurus bahianus (family Acanthuridae) and the diurnal carnivore species Pseudopeneus maculatus (family Mullidae) were relatively scarce in H. stipulacea. The catch from sand was much smaller, compared to vegetated habitats, and comprised only L. synagris, H. flavolineatum, and H. aurolineatum. These results provide evidence of reduced family diversity and altered juvenile fish assemblages in H. stipulacea, driven by an abundance of some nocturnal carnivores and scarcity of herbivores and diurnal carnivores. The findings from the present work underpin the need for further investigation and mitigation of this invasion, particularly where H. stipulacea is

  13. The Application of DNA Barcodes for the Identification of Marine Crustaceans from the North Sea and Adjacent Regions

    PubMed Central

    Raupach, Michael J.; Barco, Andrea; Steinke, Dirk; Beermann, Jan; Laakmann, Silke; Mohrbeck, Inga; Neumann, Hermann; Kihara, Terue C.; Pointner, Karin; Radulovici, Adriana; Segelken-Voigt, Alexandra; Wesse, Christina; Knebelsberger, Thomas

    2015-01-01

    During the last years DNA barcoding has become a popular method of choice for molecular specimen identification. Here we present a comprehensive DNA barcode library of various crustacean taxa found in the North Sea, one of the most extensively studied marine regions of the world. Our data set includes 1,332 barcodes covering 205 species, including taxa of the Amphipoda, Copepoda, Decapoda, Isopoda, Thecostraca, and others. This dataset represents the most extensive DNA barcode library of the Crustacea in terms of species number to date. By using the Barcode of Life Data Systems (BOLD), unique BINs were identified for 198 (96.6%) of the analyzed species. Six species were characterized by two BINs (2.9%), and three BINs were found for the amphipod species Gammarus salinus Spooner, 1947 (0.4%). Intraspecific distances with values higher than 2.2% were revealed for 13 species (6.3%). Exceptionally high distances of up to 14.87% between two distinct but monophyletic clusters were found for the parasitic copepod Caligus elongatus Nordmann, 1832, supporting the results of previous studies that indicated the existence of an overlooked sea louse species. In contrast to these high distances, haplotype-sharing was observed for two decapod spider crab species, Macropodia parva Van Noort & Adema, 1985 and Macropodia rostrata (Linnaeus, 1761), underlining the need for a taxonomic revision of both species. Summarizing the results, our study confirms the application of DNA barcodes as highly effective identification system for the analyzed marine crustaceans of the North Sea and represents an important milestone for modern biodiversity assessment studies using barcode sequences. PMID:26417993

  14. The Application of DNA Barcodes for the Identification of Marine Crustaceans from the North Sea and Adjacent Regions.

    PubMed

    Raupach, Michael J; Barco, Andrea; Steinke, Dirk; Beermann, Jan; Laakmann, Silke; Mohrbeck, Inga; Neumann, Hermann; Kihara, Terue C; Pointner, Karin; Radulovici, Adriana; Segelken-Voigt, Alexandra; Wesse, Christina; Knebelsberger, Thomas

    2015-01-01

    During the last years DNA barcoding has become a popular method of choice for molecular specimen identification. Here we present a comprehensive DNA barcode library of various crustacean taxa found in the North Sea, one of the most extensively studied marine regions of the world. Our data set includes 1,332 barcodes covering 205 species, including taxa of the Amphipoda, Copepoda, Decapoda, Isopoda, Thecostraca, and others. This dataset represents the most extensive DNA barcode library of the Crustacea in terms of species number to date. By using the Barcode of Life Data Systems (BOLD), unique BINs were identified for 198 (96.6%) of the analyzed species. Six species were characterized by two BINs (2.9%), and three BINs were found for the amphipod species Gammarus salinus Spooner, 1947 (0.4%). Intraspecific distances with values higher than 2.2% were revealed for 13 species (6.3%). Exceptionally high distances of up to 14.87% between two distinct but monophyletic clusters were found for the parasitic copepod Caligus elongatus Nordmann, 1832, supporting the results of previous studies that indicated the existence of an overlooked sea louse species. In contrast to these high distances, haplotype-sharing was observed for two decapod spider crab species, Macropodia parva Van Noort & Adema, 1985 and Macropodia rostrata (Linnaeus, 1761), underlining the need for a taxonomic revision of both species. Summarizing the results, our study confirms the application of DNA barcodes as highly effective identification system for the analyzed marine crustaceans of the North Sea and represents an important milestone for modern biodiversity assessment studies using barcode sequences.

  15. Two year study of swash zone suprabenthos of two Galician beaches (NW Spain)

    NASA Astrophysics Data System (ADS)

    Bernardo-Madrid, Rubén; Martínez-Vázquez, Juan M.; Viéitez, José M.; Junoy, Juan

    2013-10-01

    The suprabenthos is considered a major food resource for some fish and birds. Moreover, it plays a key role in the food chain and in nutrient regeneration in the surf zone. The aim of this study was to determine the factors that regulate this fauna and the differences between the suprabenthic groups, to study the possibility of seasonal variations and to compare these results with those of other studies conducted in Europe. A study and geographical comparison was conducted of the temporal patterns of the suprabenthos in the swash zone at two sandy beaches on the NE Atlantic coast (Altar and Ladeira beaches) in the NW of Spain. The study was carried out from September 2005 to August 2007 (24 months). To study the fauna, 60 m2 was sampled monthly with a suprabenthic sledge, and a total of 101 species belonging to Peracarida and Decapoda were recorded. Total densities ranged from 0.42 ind·m- 2 to 178.75 ind·m- 2. Ladeira beach showed higher densities and species richness than Altar beach, and the biocoenosis showed a different dynamic over the 24 months and between years and locations. These results indicate that there is no clear seasonality in the dynamic of suprabenthic species, although the variance of Peracarida orders was explained in diverse degree by environmental variables. The environmental models implemented explained between 27.7% and 93.8% of the faunal data, and hydrodynamic factors and daily global irradiance were selected as the best factors to explain the temporal variations.

  16. Impacts of Habitat Complexity on Physiology: Purple Shore Crabs Tolerate Osmotic Stress for Shelter

    NASA Astrophysics Data System (ADS)

    McGaw, I. J.

    2001-12-01

    Purple shore crabs, Hemigrapsus nudus (Crustacea: Decapoda), can survive indefinitely in salinities of 8 (25% SW), but also tolerate short-term exposure to salinities as low as 2. In the laboratory their salinity preference range, determined from choice chamber experiments, is 22-32 and they can discriminate between pairs of salinities separated by a difference of 2. These crabs show a strong positive thigmotaxis and a weak negative phototaxis and tend to choose environments with available shelter. The presence of shelter significantly alters the behaviour of this species. When shelter is available the salinity preference range is 10-32. Even in salinities below this preference range, the presence of shelter prolongs the time spent in the lower test salinities. This change in behaviour has implications on the crab's physiology: the haemolymph osmolality falls to lower levels when crabs remain in low salinity under shelters. In the field, H. nudus is found in creeks with salinities close to freshwater and they may remain in this salinity for up to 11 h, if there are rocks under which to shelter. An increase in habitat complexity increases the number of crabs that are found within the creek. These crabs in the low salinity environment have a lower haemolymph osmolality than crabs on the nearby open shore. In H. nudus the behavioural selection of a shelter appears to outweigh the physiological costs associated with osmotic regulation of the body fluids. Therefore, the distribution of H. nudus in estuaries may depend more on the availability of suitable habitats rather than the salinity tolerance of this species.

  17. Histopathological effects of chlorpyrifos on the gills, hepatopancreas and gonads of the freshwater crab Zilchiopsis collastinensis. Persistent effects after exposure.

    PubMed

    Negro, C L; Collins, P

    2017-06-01

    Sublethal effects of the pesticide chlorpyrifos were evaluated in the crab Zilchiopsis collastinensis (Decapoda, Trichodactylidae). Crabs were exposed to high concentrations of chlorpyrifos at the beginning of the experiment and controlled dilution, under natural light and temperature conditions. A control and three concentrations (22.4, 41.25 and 61.4µg chlorpyrifos L -1 ) were evaluated in triplicate. Nine crabs per concentration and day were used. The gills, hepatopancreas and ovaries were sampled before pesticide exposure (day 0) and 8, 15 and 22 days later, when concentrations were diluted and below the detection limits. The histopathological effects and their variations in time were observed and quantified. In gills, hyperplasias were observed in several cases, mainly in crabs exposed to chlorpyrifos. The number of collapsed lamellae and the number of affected lamellae quickly increased in exposed crabs, as effects were observed on day 8 and remained until day 22. In hepatopancreas there was an increase in the number of F and B -cells and affected tubules, especially after 22 days of exposure (p<0.05). In ovaries, there were no effects on gonadosomatic indexes or oocyte volume, but there was a significant increase in the atretic oocyte proportion related to pesticide exposure (p<0.05). The histopathological effects on the gills, hepatopancreas and ovaries were observed after exposure and persist even after dilution, and might be related to earlier exposures. Thus, these histopathological effects might be used as pesticide biomarkers even after the pesticide is not detected by chemical methods. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Effects of temperature and Ca2+ on the larval development of the decapoda crustacean: Eriocheir sinensis

    NASA Astrophysics Data System (ADS)

    Huang, Bo; Du, Nan-Shan; Lai, Wei

    2001-09-01

    With increasing demand in China for the mitten crab larvae, understanding its survival mechanism gets more important. This research focused on the effects of temperature and Ca2+ on the larval growth and development. Eriocheir sinensis larvae were reared in laboratory under, 21 different combinations of temperature (15, 20, 25°C) and Ca2+ content (120, 130, 140, 150, 160, 170, 180 mg/l) and constant salinity (20) and pH (8). The results suggested that the survival rate increases with temperature and Ca2+ content. These combinations of temperature and Ca2+ content maximized survival rate in our study and it may be the optimum water environmental conditions for culturing, the larvae. To predict surviving larvae number under different water environmental conditions, 21 dynamic mathematical models were developed. This for the first time observation of the zoeal VI larvae of the Changjiang River E. sinesis population showed that they occurred under stressed water environmental conditions: temperature of 15°C and Ca2+ content of 120, 130 mg/l.

  19. Sites of release of Putative Sex Pheromone and Sexual Behaviour in Female Carcinus maenas(Crustacea: Decapoda)

    NASA Astrophysics Data System (ADS)

    Bamber, S. D.; Naylor, E.

    1997-02-01

    Pre-moult female Carcinus maenasurine was confirmed as a source of putative sex pheromone. The sexual and temporal specificity of bioactivity in pre-moult female urine was demonstrated when urine samples taken from inter-moult and pre-moult male crabs, and inter-moult females, failed to generate a sexual response from receptive males. Detection sensitivity of male crabs to pre-moult female urine was established at a dilution factor of 1 μl of urine in 10 ml of seawater. Experimental blockage of the site of urine release (the antennal gland opercula) failed to diminish the chemical attractiveness of pre-moult female crabs to test males, implicating at least one further site of putative pheromone release. Observations of female sexual behaviour demonstrated an active role by pre-moult and post-moult female crabs when introduced to male crabs whose locomotor movement had been temporarily restricted.

  20. A unique form of light reflector and the evolution of signalling in Ovalipes (Crustacea: Decapoda: Portunidae)

    PubMed Central

    Parker, A. R.; Mckenzie, D. R.; Ahyong, S. T.

    1998-01-01

    The first demonstration, to our knowledge, of an evolutionary shift in communication mode in animals is presented. Some species of Ovalipes display spectacular iridescence resulting from multilayer reflectors in the cuticle. This reflector is unique in animals because each layer is corrugated and slightly out of phase with adjacent layers. Solid layers are separated from fluid layers in the reflector by side branches acting as support struts. An effect of this reflector is that blue light is reflected over a 'broad' angle around a plane parallel to the sea floor when the host crab is resting. Species of Ovalipes all possess stridulatory structures. The shallow-water species with the best developed stridulatory structures are non-iridescent and use sound as a signal. Deep-water species possess poorly developed stridulatory structures and display iridescence from most regions of the body. In deep water, where incident light is blue, light display is highly directional in contrast to sound produced via stridulation. Sound and light display probably perform the same function of sexual signalling in Ovalipes, although the directional signal is less likely to attract predators. Deep-water species of Ovalipes appear to have evolved towards using light in conspecific signalling. This change from using sound to using light reflects the change in habitat light properties, perhaps the hunting mechanisms of cohabitees, and its progression is an indicator of phylogeny. The changes in sexual signalling mechanisms, following spatial–geographical isolation, may have promoted speciation in Ovalipes.

  1. Nematocarcinus Milne Edwards, 1881 (Crustacea, Decapoda) from Southwestern Atlantic, including the Southern Mid-Atlantic Ridge area.

    PubMed

    Cardoso, Irene A; Burukovsky, Rudolf N

    2014-11-26

    The deep sea shrimp genus Nematocarcinus Milne Edwards, 1881 includes 47 species, ten of them have been recorded from the Atlantic Ocean. Herein, material sampled during three scientific projects (REVIZEE Central Fishery project; Campos Basin Deep Sea Environmental Project; Evaluation of Environmental Heterogeneity in the Campos Basin) made in the Southwestern Atlantic, off Brazil, is examined. In addition, material sampled from the South Mid Atlantic Ridge (MAR-ECO Project) was also examined. Four species are recorded for the first time to the southwestern Atlantic Ocean including Mid Atlantic Ridge area: Nematocarcinus faxoni Burukovsky, 2001; N. gracilipes Filhol, 1884; N. rotundus Crosnier & Forest, 1973 and N. tenuipes Spence-Bate, 1888.

  2. Small-scale distribution characteristics of Munida spp. populations (Decapoda: Anomura) off the Catalan coasts (western Mediterranean)

    NASA Astrophysics Data System (ADS)

    Huguet, Carme; Maynou, Francesc; Abelló, Pere

    2005-04-01

    The small-scale distribution characteristics of three species of the anomuran genus Munida, namely Munida rutllanti, Munida intermedia and Munida tenuimana, have been studied on the lower shelf and upper-middle continental slope near the coasts of Tarragona and the Ebro delta region in the western Mediterranean. The differential bathymetric distribution showed that a fair degree of overlap exists between M. rutllanti and M. intermedia, with the former being mainly found at shallower depths. The size population structure of the three species showed that polymodality, as indicative of a longer life-span and of a higher degree of population structuring was more evident in the deeper-living species, whereas unimodality, as an indication of a recruitment dependent population, was more evident in the shallowest-occurring species. Geostatistics have been applied to determine the degree of spatial variability occurring in M. intermedia abundance, the better-sampled species. The Mantel test has been used to assess the significance of the overlap between the three species distributions as well as the relation between certain population parameters. A discussion on the population characteristics of M. rutllanti is made in relation with its expansion along the western Mediterranean in the last decades.

  3. Monomia calla, a new species of swimming crab (Decapoda, Portunidae)
    from Madagascar and the Philippines.

    PubMed

    Koch, Milan; Nguyen, Thanh Son; Ďuriš, Zdeněk

    2015-07-06

    A new species of portunid crab (Brachyura: Portunidae) from southern Madagascar and central Philippines is described. Monomia calla sp. nov. is most similar in morphology to M. lecromi (Moosa, 1996) from the Chesterfield Islands in the southwestern Pacific Ocean, and M. rubromarginata (Lanchester, 1900) from the South China Sea, Singapore, Malay Archipelago and the northern half of Australia. The new species can be easily distinguished from all congeners by the distinctive morphology of the male first gonopod. The number of species of the Indo-West Pacific genus Monomia now stands at 12.

  4. Etisus evamuellerae, a new xanthid crab (Decapoda, Brachyura) from the Middle Miocene of Austria and Hungary

    PubMed Central

    Hyžný, M.; van Bakel, B.W.M.; Guinot, D.

    2015-01-01

    On the basis of several carapaces, a new species of xanthid crab, Etisus evamuellerae, is described from the Middle Miocene of the Vienna (Austria) and Great Hungarian basins. It differs from the coeval xanthids, Xantho moldavicus and Pilodius vulgaris, in having a distinctly protruding front and comparatively longer carapace. Contrary to those two species, the new one makes up for just a small percentage in the decapod crustacean assemblages studied. PMID:25983383

  5. Revision of the freshwater genus Atyaephyra (Crustacea, Decapoda, Atyidae) based on morphological and molecular data

    PubMed Central

    Christodoulou, Magdalini; Antoniou, Aglaia; Antonios Magoulas;  Athanasios Koukouras

    2012-01-01

    Abstract Atyaephyra de Brito Capello, 1867 was described from the Mediterranean region almost 200 years ago. Since then, the genus has been recorded from various freshwater habitats in Europe, North Africa and the Middle East. Despite its long history, the taxonomic status of Atyaephyra species remains confusing and uncertain. Consequently numerous specimens from the known range of Atyaephyra were analysed using morphological characters and mitochondrial COI sequences in an attempt to clarify the taxonomy of this genus. The present study recognises seven Atyaephyra species, more than twice as many as previously recorded (three), four of which are considered as new. The new species are described, additional information to the original descriptions are provided for the remaining three taxa, while neotypes of Atyaephyra desmarestii Millet, 1831 and Atyaephyra stankoi Karaman, 1972 are designated to stabilize their taxonomy. Non-overlapping distinguishing morphological characters are used to discriminate the examined material into five species, e.g., Atyaephyra desmarestii, Atyaephyra stankoi, Atyaephyra orientalis Bouvier, 1913, Atyaephyra thyamisensis sp. n., Atyaephyra strymonensis sp. n. In addition, the genetic analysis supports the existence of multiple phylogenetic clades in the broader Mediterranean area and distinguishes two new cryptic species, namely Atyaephyra tuerkayi sp. n. and Atyaephyra acheronensis sp. n. The geographic distribution of these species is confirmed and their phylogenetic relationships are described. PMID:23166474

  6. A new record of pasiphaeid shrimp of the genus Pasiphaea (Crustacea: Decapoda: Caridea) in Korean waters

    NASA Astrophysics Data System (ADS)

    Kim, Jung Nyun; Choi, Jung Hwa; Jo, Hyun-su

    2016-09-01

    A single specimen of the pelagic shrimps, Pasiphaea japonica Omori, 1976 (Pasiphaeidae) collected in the southeastern waters of Korea is described and illustrated. Although this species occurs widely in the Indo-West Pacific including the Japanese coast of the East/Japan Sea and the middle and southern parts of the East China Sea, this is the first record of the species and the genus in Korean waters. The species is distinguished from other congeners by the following combination of characteristics: non-carinate dorsal sixth abdominal somite with a terminal tooth, rudimentary pleurobranch on the eighth thoracic somite, merus of the first pereopod with more than eight spines, and almost entirely transparent white color.

  7. From the Palaeontological Collection of the Universalmuseum Joanneum – The Cenozoic Decapod Crustaceans (Crustacea: Malacostraca: Decapoda)

    PubMed Central

    Hyžný, Matúš; Gross, Martin

    2017-01-01

    Cenozoic decapod crustaceans housed in the collections of the Universalmuseum Joanneum (Graz, Austria) are reviewed. Previous descriptions, geographic and stratigraphic provenance and collection history are discussed. Altogether 72 specimens are figured, including five holotypes. Taxonomic affinity of previously unpublished material is addressed. Gebiacantha sp. from the middle Miocene of Wetzelsdorf is the first fossil record of the genus from the Paratethys. PMID:28239309

  8. Recent settlement trends in Panulirus argius (Decapoda: Palinuridae) pueruli around St. Thomas, U.S. Virgin Islands.

    PubMed

    Kojis, B L; Quinn, N J; Caseau, S M

    2003-06-01

    Puerulus settlement of the western Atlantic spiny lobster, Panulirus argus, was monitored using modified Witham collectors from December 1996 to March 1998 at seven sites around St. Thomas, U.S. Virgin Islands. A total of 605 pueruli were collected from 553 samples for a catch per unit effort (CPUE) for all sites of 1.09 pueruli. The greatest settlement occurred on sites within a recently declared marine reserve, which had an overall CPUE of 1.77 pueruli. Settlement in non-reserve sites was much lower with an overall CPUE of 0.31 pueruli. Pueruli recruitment declined 67% at inshore sites and 53% at offshore sites between July 1992 - April 1994 and February 1997 - March 1998. Also, only 10% of months sampled in 1997-98 had a CPUE > 0.5 compared to 55% in a previous study in 1992 - 1993. Despite the decline in pueruli CPUE in 1997-98 compared to 1992-94, the commercial lobster catch in the 2000-01 fishing season, and by inference the adult lobster population (legal lobster size in the US Virgin Islands is > or = 3.5 cm carapace length), remained stable.

  9. Monomia lucida sp. nov., a new swimming crab (Crustacea: Decapoda: Portunidae) from the South China Sea.

    PubMed

    Koch, Milan; ĎuriŠ, ZdenĚk

    2018-02-27

    A new species of the portunid genus, Monomia Gistel, 1848, is described from the South China Sea in Vietnam. Monomia lucida sp. nov. is morphologically most similar to M. argentata (A. Milne-Edwards, 1861), which was originally described from Sarawak, on the island of Borneo. In addition to the stout, forward-directed anterolateral teeth of the carapace, the subrectangular sixth segment of the male pleon, and the long and slender laterally bent first gonopods, adults of the new species reach a greater size, and can also be distinguished from M. argentata by the colour pattern on the natatory dactylus. The independent specific status of M. lucida sp. nov. is also supported by molecular evidence. Aside from a comparison of this new species with other known congeners, new photographs of the holotype of M. samoensis (Ward, 1939) are also provided.

  10. Extended hatching periods in the subantarctic lithodid crabs Lithodes santolla and Paralomis granulosa (Crustacea: Decapoda: Lithodidae)

    NASA Astrophysics Data System (ADS)

    Thatje, S.; Calcagno, J. A.; Lovrich, G. A.; Sartoris, F. J.; Anger, K.

    2003-06-01

    Temporal pattern of hatching was studied in the subantarctic lithodid crabs Lithodes santolla (Molina) and Paralomis granulosa (Jaquinot) from the Argentine Beagle Channel. In both species, larval hatching occurred in low daily numbers over an extended period of up to several weeks, depending on hatch size. Low daily hatching activity and low oxygen-consumption rates in freshly hatched P. granulosa larvae are discussed as life history adaptations to, and/or physiological constraints by, the environmental conditions of high latitudes.

  11. Central projections of antennular chemosensory and mechanosensory afferents in the brain of the terrestrial hermit crab (Coenobita clypeatus; Coenobitidae, Anomura)

    PubMed Central

    Tuchina, Oksana; Koczan, Stefan; Harzsch, Steffen; Rybak, Jürgen; Wolff, Gabriella; Strausfeld, Nicholas J.; Hansson, Bill S.

    2015-01-01

    The Coenobitidae (Decapoda, Anomura, Paguroidea) is a taxon of hermit crabs that includes two genera with a fully terrestrial life style as adults. Previous studies have shown that Coenobitidae have evolved a sense of spatial odor localization that is behaviorally highly relevant. Here, we examined the central olfactory pathway of these animals by analyzing central projections of the antennular nerve of Coenobita clypeatus, combining backfilling of the nerve with dextran-coupled dye, Golgi impregnations and three-dimensional reconstruction of the primary olfactory center, the antennular lobe. The principal pattern of putative olfactory sensory afferents in C. clypeatus is in many aspects similar to what have been established for aquatic decapod crustaceans, such as the spiny lobster Panulirus argus. However, there are also obvious differences that may, or may not represent adaptations related to a terrestrial lifestyle. In C. clypeatus, the antennular lobe dominates the deutocerebrum, having more than one thousand allantoid-shaped subunits. We observed two distinct patterns of sensory neuron innervation: putative olfactory afferents from the aesthetascs either supply the cap/subcap region of the subunits or they extend through its full depth. Our data also demonstrate that any one sensory axon can supply input to several subunits. Putative chemosensory (non-aesthetasc) and mechanosensory axons represent a different pathway and innervate the lateral and median antennular neuropils. Hence, we suggest that the chemosensory input in C. clypeatus might be represented via a dual pathway: aesthetascs target the antennular lobe, and bimodal sensilla target the lateral antennular neuropil and median antennular neuropil. The present data is compared to related findings in other decapod crustaceans. PMID:26236202

  12. Phylogenomic analysis of Copepoda (Arthropoda, Crustacea) reveals unexpected similarities with earlier proposed morphological phylogenies.

    PubMed

    Eyun, Seong-Il

    2017-01-19

    Copepods play a critical role in marine ecosystems but have been poorly investigated in phylogenetic studies. Morphological evidence supports the monophyly of copepods, whereas interordinal relationships continue to be debated. In particular, the phylogenetic position of the order Harpacticoida is still ambiguous and inconsistent among studies. Until now, a small number of molecular studies have been done using only a limited number or even partial genes and thus there is so far no consensus at the order-level. This study attempted to resolve phylogenetic relationships among and within four major copepod orders including Harpacticoida and the phylogenetic position of Copepoda among five other crustacean groups (Anostraca, Cladocera, Sessilia, Amphipoda, and Decapoda) using 24 nuclear protein-coding genes. Phylogenomics has confirmed the monophyly of Copepoda and Podoplea. However, this study reveals surprising differences with the majority of the copepod phylogenies and unexpected similarities with postembryonic characters and earlier proposed morphological phylogenies; More precisely, Cyclopoida is more closely related to Siphonostomatoida than to Harpacticoida which is likely the most basally-branching group of Podoplea. Divergence time estimation suggests that the origin of Harpacticoida can be traced back to the Devonian, corresponding well with recently discovered fossil evidence. Copepoda has a close affinity to the clade of Malacostraca and Thecostraca but not to Branchiopoda. This result supports the hypothesis of the newly proposed clades, Communostraca, Multicrustacea, and Allotriocarida but further challenges the validity of Hexanauplia and Vericrustacea. The first phylogenomic study of Copepoda provides new insights into taxonomic relationships and represents a valuable resource that improves our understanding of copepod evolution and their wide range of ecological adaptations.

  13. Genome-wide analyses of the bHLH superfamily in crustaceans: reappraisal of higher-order groupings and evidence for lineage-specific duplications

    PubMed Central

    2018-01-01

    The basic helix-loop-helix (bHLH) proteins represent a key group of transcription factors implicated in numerous eukaryotic developmental and signal transduction processes. Characterization of bHLHs from model species such as humans, fruit flies, nematodes and plants have yielded important information on their functions and evolutionary origin. However, relatively little is known about bHLHs in non-model organisms despite the availability of a vast number of high-throughput sequencing datasets, enabling previously intractable genome-wide and cross-species analyses to be now performed. We extensively searched for bHLHs in 126 crustacean species represented across major Crustacea taxa and identified 3777 putative bHLH orthologues. We have also included seven whole-genome datasets representative of major arthropod lineages to obtain a more accurate prediction of the full bHLH gene complement. With focus on important food crop species from Decapoda, we further defined higher-order groupings and have successfully recapitulated previous observations in other animals. Importantly, we also observed evidence for lineage-specific bHLH expansions in two basal crustaceans (branchiopod and copepod), suggesting a mode of evolution through gene duplication as an adaptation to changing environments. In-depth analysis on bHLH-PAS members confirms the phenomenon coined as ‘modular evolution’ (independently evolved domains) typically seen in multidomain proteins. With the amphipod Parhyale hawaiensis as the exception, our analyses have focused on crustacean transcriptome datasets. Hence, there is a clear requirement for future analyses on whole-genome sequences to overcome potential limitations associated with transcriptome mining. Nonetheless, the present work will serve as a key resource for future mechanistic and biochemical studies on bHLHs in economically important crustacean food crop species. PMID:29657824

  14. Monitoring of noble, signal and narrow-clawed crayfish using environmental DNA from freshwater samples.

    PubMed

    Agersnap, Sune; Larsen, William Brenner; Knudsen, Steen Wilhelm; Strand, David; Thomsen, Philip Francis; Hesselsøe, Martin; Mortensen, Peter Bondgaard; Vrålstad, Trude; Møller, Peter Rask

    2017-01-01

    For several hundred years freshwater crayfish (Crustacea-Decapoda-Astacidea) have played an important ecological, cultural and culinary role in Scandinavia. However, many native populations of noble crayfish Astacus astacus have faced major declines during the last century, largely resulting from human assisted expansion of non-indigenous signal crayfish Pacifastacus leniusculus that carry and transmit the crayfish plague pathogen. In Denmark, also the non-indigenous narrow-clawed crayfish Astacus leptodactylus has expanded due to anthropogenic activities. Knowledge about crayfish distribution and early detection of non-indigenous and invasive species are crucial elements in successful conservation of indigenous crayfish. The use of environmental DNA (eDNA) extracted from water samples is a promising new tool for early and non-invasive detection of species in aquatic environments. In the present study, we have developed and tested quantitative PCR (qPCR) assays for species-specific detection and quantification of the three above mentioned crayfish species on the basis of mitochondrial cytochrome oxidase 1 (mtDNA-CO1), including separate assays for two clades of A. leptodactylus. The limit of detection (LOD) was experimentally established as 5 copies/PCR with two different approaches, and the limit of quantification (LOQ) were determined to 5 and 10 copies/PCR, respectively, depending on chosen approach. The assays detected crayfish in natural freshwater ecosystems with known populations of all three species, and show promising potentials for future monitoring of A. astacus, P. leniusculus and A. leptodactylus. However, the assays need further validation with data 1) comparing traditional and eDNA based estimates of abundance, and 2) representing a broader geographical range for the involved crayfish species.

  15. The role of water chemistry in the distribution of Austropotamobius pallipes (Crustacea Decapoda Astacidae) in Piedmont (Italy).

    PubMed

    Favaro, Livio; Tirelli, Tina; Pessani, Daniela

    2010-01-01

    Over the last decades, the populations of Austropotamobius pallipes have decreased markedly all over Europe. If we evaluate the ecological factors that determine its presence, we will have information that could guide conservation decisions. This study aims to investigate the chemical-physical demands of A. pallipes in NW Italy. To this end, we investigated 98 sites. We performed Principal Component Analysis using chemical-physical parameters, collected in both presence and absence sites. We then used principal components with eigenvalue > 1 to run Discriminant Function Analysis and Logistic Regression. The statistics on the concentration of Ca(2+), water hardness, pH and BOD(5) were significantly different in the presence and in the absence sites. pH and BOD(5) played the most important role in separating the presence from the absence locations. These findings are further evidence that we should reduce dissolved organic matter and fine particles in order to contribute to species management and conservation. Copyright 2009 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  16. Functional morphology of comminuting feeding structures of Trichodactylus borellianus (Brachyura, Decapoda, Trichodactylidae), an omnivorous freshwater crab.

    PubMed

    Carvalho, Débora de Azevedo; Viozzi, Maria Florencia; Collins, Pablo Agustín; Williner, Verónica

    2017-07-01

    Crustaceans exhibit great diversity of feeding structures with morphological traits that are useful to infer the general trophic habits of species. In this study, we analyzed the functional morphology of comminuting feeding structures (mandibles, chelipeds, gastric mill) of the freshwater crab Trichodactylus borellianus directly related with the food fragmentation. The heterochely and mechanical advantage (MA) of the chelae were also studied. In both analyses, we considered the relationship between morphology and the natural diet. We expected to find a consistent relation between feeding habits and morphological traits. In general, we found simple structures armed with uniform setal systems and feeding appendages without pronounced teeth or spines. Mandibles have primarily cutting functions, helping with the food anchoring and fragmentation with mandibular palps armed with pappose setae. Chelipeds were covered with spines and simple setae. Adult males exhibited right-handedness with high MA of the major chelae. The ingested, relatively large pieces of food are finally chewed by a gastric mill equipped with sharp cusps characteristic of decapods with low ingestion of crude fiber material. The morphology of the feeding apparatus revealed that it is well adapted to an omnivorous diet, being able to cope with dietary changes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. New genus and species of brachyuran crab from the southern East Pacific Rise (Crustacea Decapoda Brachyura Bythograeidae).

    PubMed

    Guinot, Danièle; Hurtado, Luis Alberto; Vrijenhoek, Robert

    2002-11-01

    A new genus and species of a brachyuran crab, Allograea tomentosa n. gen. and n. sp., of the family Bythograeidae, collected at a hydrothermal vent locality south of the Easter Microplate (31 degrees 09'S) on the southern East Pacific Rise, is described. The genus Allograea is distinguished by lacking modifications of the fronto-orbital region, and by the absence of coloured fields and setal patches on the carapace and chelipeds. The body and legs are smooth but densely covered by a brown tomentum, the eyestalks are not reduced, but the cornea is unfaceted and unpigmented. Comparison of mitochondrial DNA sequences among all known bythograeid genera confirms the novelty of this taxon.

  18. [Temporal and spatial distribution of the crab Callinectes sapidus (Decapoda: Portunidae) in Chetumal Bay, Quintana Roo, Mexico].

    PubMed

    Ortiz-León, Héctor J; Jesús-Navarrete, Alberto de; Cordero, Eloy Sosa

    2007-03-01

    In order to determine temporal and spatial distribution patterns of Callinectes sapidus, samplings were carried out during the cold-front (January-February), dry (May-June) and rainy (August-September, 2002) climatic seasons, in 30 sampling stations of Chetumal Bay, grouped in sectors A (14 stations), B (eight stations) and C (eight stations). In each sampling station crabs were collected from two transects parallel to the coast, each with three traps, separated by 30 m. Sediments were calcareous coarse and medium sand, white or lightly gray. A total of 1 031 specimens were collected. CPEU (Capture Per Effort Unit) differed spatially and temporally. Highest CPEU was found in sector C with 1.3 ind.trap(-1), and in the rainy season with 1.1 ind.trap(-1). Population was predominantly composed of male individuals. The male:female ratio was 15:1. Males and adults (group II) CPEU was significant different between sectors and climatic seasons. Both males and adults (group II) had a greater CPEU in sector C (1.2 ind.trap-) and in the rainy season (1.1 ind.trap(-1)). Abundance of female and juvenile individuals (group I) was low during the sampling period whereas group 0 juvenile individuals were not found. A greater relative frequency between sectors and climatic seasons were observed in 130-139 mm and 140-149 mm size interval (CW). C. sapidus occurred on sandy sediments in Chetumal Bay. Pearson product moment correlations exhibited significant relationships between CPEU and temperature, salinity and dissolved oxygen. In Chetumal Bay, the spatial and temporal distribution of C. sapidus can be related to salinity, temperature, habitat quality, food availability, recruitment and reproduction events of individuals.

  19. On the morphology of the central nervous system in larval stages of Carcinus maenas L. (Decapoda, Brachyura)

    NASA Astrophysics Data System (ADS)

    Harzsch, S.; Dawirs, R. R.

    1993-02-01

    We investigated the morphology of the central nervous system throughout the larval development of Carcinus maenas. For that purpose single larvae were reared in the laboratory from hatching through metamorphosis. Complete series of whole mout semithin sections were obtained from individuals of all successive larval stages and analysed with a light microscope. Morphological feature and spatial arrangement of discernable neural cell clusters, fibre tracts and neuropile are described and compared with the adult pattern. We found that most of the morphological features characterizing the adult nervous system are already present in the zoea-1. Nevertheless, there are marked differences with respect to the arrangement of nerve cell bodies, organization of cerebral neuropile, and disposition of ganglia in the ventral nerve cord. It appears that complexity of the central nervous neuropile is selectively altered during postmetamorphotic development, probably reflecting adaptive changes of sensory-motor integration in response to behavioural maturation. In contrast, during larval development there was little change in the overall structural organization of the central nervous system despite some considerable growth. However, the transition from zoea-4 to megalopa brings about multiple fundamental changes in larval morphology and behavioural pattern. Since central nervous integration should properly adapt to the altered behavioural repertoire of the megalopa, it seems necessary to ask in which respect synaptic rearrangement might characterize development of the central nervous system.

  20. Characteristics of Scylla spp. (Decapoda: Portunidae) and their mangrove forest habitat in Ngaremeduu Bay, Republic of Palau

    Treesearch

    Katherine C. Ewel; Stacy Rowe; Blake McNaughton; Kimberly M. Bonine

    2009-01-01

    Three species of mangrove crabs (Scylla spp.) were captured in live traps in Ngaremeduu Bay on the island of Babeldaob, Republic of Palau. Most were S. serrata, but one individual each of S. olivacea and S. paramamosain was also trapped, establishing existence of a biogeographic...

  1. Deep under the sea: unraveling the evolutionary history of the deep-sea squat lobster Paramunida (Decapoda, Munididae).

    PubMed

    Cabezas, Patricia; Sanmartín, Isabel; Paulay, Gustav; Macpherson, Enrique; Machordom, Annie

    2012-06-01

    The diversification of Indo-Pacific marine fauna has long captivated the attention of evolutionary biologists. Previous studies have mainly focused on coral reef or shallow water-associated taxa. Here, we present the first attempt to reconstruct the evolutionary history--phylogeny, diversification, and biogeography--of a deep-water lineage. We sequenced the molecular markers 16S, COI, ND1, 18S, and 28S for nearly 80% of the nominal species of the squat lobster genus Paramunida. Analyses of the molecular phylogeny revealed an accelerated diversification in the late Oligocene-Miocene followed by a slowdown in the rate of lineage accumulation over time. A parametric biogeographical reconstruction showed the importance of the southwest Pacific area, specifically the island arc of Fiji, Tonga, Vanuatu, Wallis, and Futuna, for diversification of squat lobsters, probably associated with the global warming, high tectonic activity, and changes in oceanic currents that took place in this region during the Oligocene-Miocene period. These results add strong evidence to the hypothesis that the Neogene was a period of major diversification for marine organisms in both shallow and deep waters. © 2012 The Author(s). Evolution © 2012 The Society for the Study of Evolution.

  2. Luminous vibriosis in rock lobster Jasus verreauxi (Decapoda: Palinuridae) phyllosoma larvae associated with infection by Vibrio harveyi.

    PubMed

    Diggles, B K; Moss, G A; Carson, J; Anderson, C D

    2000-11-14

    Studies were conducted to determine the cause of outbreaks of luminous vibriosis in phyllosoma larvae of the packhorse rock lobster Jasus verreauxi reared in an experimental culture facility. On 2 separate occasions mortalities of up to 75% over a period of 4 wk were observed in 4th to 5th and 8th to 10th instar phyllosomas at water temperatures of 20 and 23 degrees C, respectively. Affected larvae became opaque, exhibited small red spots throughout the body and pereiopods, and were faintly luminous when viewed in the dark. Histopathology showed that the gut and hepatopancreas tubules of moribund phyllosomas contained massive bacterial plaques. The hepatopancreas tubules of moribund larvae were atrophic and some contained necrotic cells sloughed into the lumen. Dense, pure cultures of a bacterium identified as Vibrio harveyi were isolated from moribund larvae. The disease syndrome was reproduced by in vivo challenge and V. harveyi was successfully reisolated from diseased larvae after apparently healthy larvae were exposed by immersion to baths of more than 10(4) V. harveyi ml(-1) at 24 degrees C. Injured larvae were more susceptible to infection than were healthy larvae. Survival of larvae experimentally and naturally exposed to V. harveyi was improved when antibiotics were administered via bath exposures.

  3. A new species of deep-sea sponge-associated shrimp from the North-West Pacific (Decapoda, Stenopodidea, Spongicolidae).

    PubMed

    Xu, Peng; Zhou, Yadong; Wang, Chunsheng

    2017-01-01

    A new species of the deep-sea spongicolid genus Spongicoloides Hansen, 1908 is described and illustrated based on material from the northwestern Pacific. Spongicoloides weijiaensis sp. n. was found inside a hexactinellid sponge, Euplectella sp., sampled by the Chinese manned submersible "Jiaolong" at depths of 2279 m near the Weijia Guyot, in the Magellan Seamount Chain. The new species can be distinguished from all congeneric species by several morphological features, involving gill formula, spination of the carapace, antennal scale, third pereiopod, telson and uropod, posteroventral teeth of the pleura, and dactyli of the fourth and fifth pereiopods. An identification key to the Pacific species of Spongicoloides is provided.

  4. A new species of deep-sea sponge-associated shrimp from the North-West Pacific (Decapoda, Stenopodidea, Spongicolidae)

    PubMed Central

    Xu, Peng; Zhou, Yadong; Wang, Chunsheng

    2017-01-01

    Abstract A new species of the deep-sea spongicolid genus Spongicoloides Hansen, 1908 is described and illustrated based on material from the northwestern Pacific. Spongicoloides weijiaensis sp. n. was found inside a hexactinellid sponge, Euplectella sp., sampled by the Chinese manned submersible “Jiaolong” at depths of 2279 m near the Weijia Guyot, in the Magellan Seamount Chain. The new species can be distinguished from all congeneric species by several morphological features, involving gill formula, spination of the carapace, antennal scale, third pereiopod, telson and uropod, posteroventral teeth of the pleura, and dactyli of the fourth and fifth pereiopods. An identification key to the Pacific species of Spongicoloides is provided. PMID:29089835

  5. Heterochrony in mandible development of larval shrimp (Decapoda: Caridea)--a comparative morphological SEM study of two carideans.

    PubMed

    Batel, Annika; Melzer, Roland R; Anger, Klaus; Geiselbrecht, Hannes

    2014-11-01

    Mandible development in the larval stages I-V of two palaemonid shrimp species, Palaemon elegans and Macrobrachium amazonicum, was analyzed using scanning electron microscopy, light microscopy, and confocal laser scanning microscopy. In contrast to the zoea I of P. elegans, first-stage larvae of M. amazonicum are nonfeeding. At hatching, the morphology of the mandibles is fully expressed in P. elegans, while it appears underdeveloped in M. amazonicum, presenting only small precursors of typical caridean features. In successive zoeal stages, both species show similar developmental changes, but the mandibular characters of the larvae in M. amazonicum were delayed compared to the equivalent stages in P. elegans, especially in the development of submarginal setae and mandible size. In conclusion, our results indicate heterochrony (postdisplacement) of mandible development in M. amazonicum compared to that in P. elegans, which is related to initial lack of mandible functionality or planktivorous feeding at hatching, respectively. This conclusion is supported by comparison with other palaemonid zoeae exhibiting different feeding modes. Our data suggest that an evolutionary ground pattern of mandible morphology is present even in species with nonfeeding first-stage larvae. © 2014 Wiley Periodicals, Inc.

  6. Hypolobocera guayaquilensis (Decapoda: Pseudothelphusidae): A New Crab Intermediate Host of Paragonimus mexicanus in Manabí Province, Ecuador

    PubMed Central

    Calvopina, Manuel; Romero-Alvarez, Daniel; Rendon, Melina; Takagi, Hidekazu; Sugiyama, Hiromu

    2018-01-01

    To determine that Paragonimus sp. is actively transmitted in a tropical area of the Pacific region of Ecuador where human cases of pulmonary paragonimiasis have recently been documented, a total of 75 freshwater crabs were collected from 2 different streams in the Pedernales area of Manabí Province, Ecuador. All collected crabs were identified as Hypolobocera guayaquilensis based on morphological characteristics of the male gonopods. The hepatopancreas of each crab was examined by compressing it between 2 glass plates followed by observation under a stereomicroscope. Excysted Paragonimus metacercariae were detected in 39 (52.0%) crabs and their densities varied from 1 to 32 per infected crab. There was a positive relationship between crab size and metacercarial density. Sequences of the second internal transcribed spacer region of the ribosomal RNA gene of the Paragonimus metacercariae obtained in this study were identical to those of Paragonimus mexicanus deposited in the DDBJ/EMBL/GenBank database. Thus, the present study is the first to confirm that the crab species H. guayaquilensis is the second intermediate host of P. mexicanus in Manabí Province, Ecuador. Because this crab might be the possible source of human infections in this area, residents should pay attention to improper crab-eating habits related with a neglected parasitic disease, i.e., paragonimiasis. PMID:29742874

  7. Molecular evidence for the Southern Hemisphere origin and deep-sea diversification of spiny lobsters (Crustacea: Decapoda: Palinuridae).

    PubMed

    Tsang, L M; Chan, T-Y; Cheung, M K; Chu, K H

    2009-05-01

    Spiny lobsters (family Palinuridae) are economically important marine animals that have been the subject of a considerable amount of research. However, the phylogeny of this group remains disputed. Morphological analyses have not been able to resolve the relationships of the various members of the group, and no agreement has yet been reached on its phylogeny as indicated by the different gene trees reported to date. In the present study, we attempt to reconstruct the phylogeny of Palinuridae and its allies using sequences from three nuclear protein-coding genes (phosphoenolpyruvate carboxykinase, sodium-potassium ATPase alpha-subunit and histone 3). The inferred topology receives strong nodal support for most of the branches. The family Palinuridae is found to be paraphyletic with the polyphyletic Synaxidae nested within it. Stridentes forms a monophyletic assemblage, indicating that the stridulating sound producing organ evolved only once in the spiny lobsters. By contrast, Silentes is paraphyletic, as Palinurellus is more closely related to Stridentes than to other Silentes genera. The three genera restricted to the southern high latitudes (Jasus, Projasus and Sagmariasus) constitute the basal lineages in the spiny lobsters, suggesting a Southern Hemisphere origin for the group. Subsequent diversification appears to have been driven by the closure of the Tethys Sea and the formation of the Antarctic circumpolar current, which isolated the northern and southern taxa. Contrary to an earlier hypothesis that postulated evolution from a deep-sea ancestral stock, the shallow-water genus Panulirus is the basal taxon in Stridentes, while the deep-sea genera Puerulus and Linuparus are found to be derived. This indicates that the spiny lobsters invaded deep-sea habitats from the shallower water rocky reefs and then radiated. Our results suggest that Synaxidae is not a valid family, and should be considered to be synonymous with Palinuridae. We also found that the previously proposed subgenera Sagmariasus and Nupalirus are genetically highly diverged, and both warrant a generic status.

  8. Identification, Characterization, and Diel Pattern of Expression of Canonical Clock Genes in Nephrops norvegicus (Crustacea: Decapoda) Eyestalk

    PubMed Central

    Sbragaglia, Valerio; Lamanna, Francesco; M. Mat, Audrey; Rotllant, Guiomar; Joly, Silvia; Ketmaier, Valerio; de la Iglesia, Horacio O.; Aguzzi, Jacopo

    2015-01-01

    The Norway lobster, Nephrops norvegicus, is a burrowing decapod with a rhythmic burrow emergence (24 h) governed by the circadian system. It is an important resource for European fisheries and its behavior deeply affects its availability. The current knowledge of Nephrops circadian biology is phenomenological as it is currently the case for almost all crustaceans. In attempt to elucidate the putative molecular mechanisms underlying circadian gene regulation in Nephrops, we used a transcriptomics approach on cDNA extracted from the eyestalk, a structure playing a crucial role in controlling behavior of decapods. We studied 14 male lobsters under 12–12 light-darkness blue light cycle. We used the Hiseq 2000 Illumina platform to sequence two eyestalk libraries (under light and darkness conditions) obtaining about 90 millions 100-bp paired-end reads. Trinity was used for the de novo reconstruction of transcriptomes; the size at which half of all assembled bases reside in contigs (N50) was equal to 1796 (light) and 2055 (darkness). We found a list of candidate clock genes and focused our attention on canonical ones: timeless, period, clock and bmal1. The cloning of assembled fragments validated Trinity outputs. The putative Nephrops clock genes showed high levels of identity (blastx on NCBI) with known crustacean clock gene homologs such as Eurydice pulchra (period: 47%, timeless: 59%, bmal1: 79%) and Macrobrachium rosenbergii (clock: 100%). We also found a vertebrate-like cryptochrome 2. RT-qPCR showed that only timeless had a robust diel pattern of expression. Our data are in accordance with the current knowledge of the crustacean circadian clock, reinforcing the idea that the molecular clockwork of this group shows some differences with the established model in Drosophila melanogaster. PMID:26524198

  9. Seasonal variations in larval biomass and biochemical composition of brown shrimp, Crangon crangon (Decapoda, Caridea), at hatching

    NASA Astrophysics Data System (ADS)

    Urzúa, Ángel; Anger, Klaus

    2013-06-01

    The "brown shrimp", Crangon crangon (Linnaeus 1758), is a benthic key species in the North Sea ecosystem, supporting an intense commercial fishery. Its reproductive pattern is characterized by a continuous spawning season from mid-winter to early autumn. During this extended period, C. crangon shows significant seasonal variations in egg size and embryonic biomass, which may influence larval quality at hatching. In the present study, we quantified seasonal changes in dry weight (W) and chemical composition (CHN, protein and lipid) of newly hatched larvae of C. crangon. Our data revealed significant variations, with maximum biomass values at the beginning of the hatching season (February-March), a decrease throughout spring (April-May) and a minimum in summer (June-September). While all absolute values of biomass and biochemical constituents per larva showed highly significant differences between months ( P < 0.001), CHN, protein and lipid concentrations (expressed as percentage values of dry weight) showed only marginally significant differences ( P < 0.05). According to generalized additive models (GAM), key variables of embryonic development exerted significant effects on larval condition at hatching: The larval carbon content (C) was positively correlated with embryonic carbon content shortly after egg-laying ( r 2 = 0.60; P < 0.001) and negatively with the average incubation temperature during the period of embryonic development ( r 2 = 0.35; P < 0.001). Additionally, water temperature ( r 2 = 0.57; P < 0.001) and food availability (phytoplankton C; r 2 = 0.39; P < 0.001) at the time of hatching were negatively correlated with larval C content at hatching. In conclusion, "winter larvae" hatching from larger "winter eggs" showed higher initial values of biomass compared to "summer larvae" originating from smaller "summer eggs". This indicates carry-over effects persisting from the embryonic to the larval phase. Since "winter larvae" are more likely exposed to poor nutritional conditions, intraspecific variability in larval biomass at hatching is interpreted as part of an adaptive reproductive strategy compensating for strong seasonality in plankton production and transitory periods of larval food limitation.

  10. A new species of Lysmata Risso, 1816 (Crustacea, Decapoda, Lysmatidae) from the Gulf of Mexico.

    PubMed

    Prakash, Sanjeevi; Baeza, J Antonio

    2017-12-12

    A new species of peppermint shrimp, Lysmata baueri n. sp., is described based on a single specimen from the eastern Gulf of Mexico. The new species can be distinguished from other morphologically similar species of Lysmata Risso, 1816 by the number of teeth, length and shape of the rostrum, the length of the antennular peduncle relative to the scaphocerite, the number of meral and ischial articles in the second pereiopods, and the number of spines on the flexor margin of the dactyli from the third to fifth pereiopods. Morphological characters demonstrate that L. baueri n. sp., is most closely related to the eastern Pacific L. californica (Stimpson, 1866), L. nayaritensis Wicksten, 2000 and L. porteri (Rathbun, 1907).

  11. Environmental covariates associated with Cambarus veteranus (Decapoda: Cambaridae), an imperiled Appalachian crayfish endemic to West Virginia, USA

    USGS Publications Warehouse

    Loughman, Zachary J.; Welsh, Stuart A.; Sadecky, Nicole M.; Dillard, Zachary W.; Scott, R. Katie

    2016-01-01

    Cambarus veteranus Faxon, 1914, a narrow endemic crayfish native to the Upper Guyandotte River Basin (UGB) in West Virginia, USA, was petitioned in 2014 by the United States Fish and Wildlife Service to be listed as endangered, but a status survey was recommended to determine if listing was warranted. During May and June 2015, surveys were undertaken across the UGB to determine the current distribution of the species. A total of 71 sites were sampled, including all streams where the species was previously recorded, as well as semi-randomly selected streams, with 1-9 125 m long sites sampled per wadeable stream. Physiochemical and physical habitat data (based on the Qualitative Habitat Evaluation Index, QHEI) were obtained at each site to determine abiotic factors that were associated with the presence of C. veteranus. Site detection or non-detection of C. veteranus and associated site covariates were modeled using logistic regression to determine covariates associated with the presence of the species. Cambarus veteranus was present in both the Pinnacle Creek and Clear Fork/Laurel Fork watersheds at 10 sites, but it was not observed in the remaining 61 sites. An additive effects model with conductivity and QHEI was selected as the best approximating model. Cambarusveteranus was associated with lower than average UGB conductivity (379 µS) and high (>80) QHEI score. All sites where C. veteranus was not detected had higher conductivity and/or lower QHEI scores.

  12. Growth and reproduction of the mangrove crab Goniopsis cruentata (Latreille, 1803) (Crustacea: Decapoda: Grapsidae) in southeastern Brazil.

    PubMed

    Reis, Carla R G; Taddei, Fabiano G; Cobo, Valter J

    2015-01-01

    Goniopsis cruentata is a common semi-terrestrial crab in Brazilian mangroves and an important fishery resource for traditional communities in the northeastern Brazilian coast. Aiming to contribute to the knowledge about the species, this study evaluated the carapace width and weight growth curves, the relative growth of weight versus carapace width, and the temporal variation of gonadosomatic and hepatosomatic indices for the species. A total of 524 crabs were collected in a mangrove area of Ubatuba municipality, state of São Paulo. The growth-curves parameters and longevity (tmax) were estimated for males (CW∞=50.6 mm, WE=56.4 g, k=2.24, t0=0.003631502 year-1, tmax=1.3 years) and females (CW∞=50.7 mm, WE∞=58.8 g, k=2.50, t0=0.003247209 year-1, tmax=1.2 years). The age at onset of sexual maturity was 0.23 years for both genders. The weight-growth model was isometric for the immature developmental stages and allometric negative for adults. The species exhibited a continuous reproduction, with breeding peaks in spring and summer months. The weight dynamics of gonads and hepatopancreas were not clearly related. The growth and reproductive patterns indicated that Goniopsis cruentata has a life-history that prioritizes reproduction instead of survival. The species exhibited some of the highest growth rates and lowest longevity estimates reported for brachyuran species in Brazil.

  13. Population biology of the mangrove crab Ucides cordatus (Decapoda: Ucididae) in an estuary from semiarid northeastern Brazil.

    PubMed

    Leite, Marcos de Miranda Leão; Rezende, Carla Ferreira; Silva, José Roberto Feitosa

    2013-12-01

    The mangrove crab Ucides cordatus is an important resource of estuarine regions along the Brazilian coast. U. cordatus is distributed from Florida, U.S.A., to the coast of Santa Catarina, Brazil. The species plays an important role in processing leaf litter in the mangroves, which optimizes the processes of energy transfer and nutrient cycling, and is considered a keystone species in the ecosystem. Population declines have been reported in different parts of the Brazilian coast. In the present study we evaluated aspects of the population structure, sex ratio and size at morphological sexual maturity. We analyzed 977 specimens collected monthly over 24 months (2010-2012), in a mangrove of the Jaguaribe River, in the municipality of Aracati on the East coast of Ceará state, Northeastern Brazil. The study area has a mild semiarid tropical climate, with mean temperatures between 26 and 28 degrees C. The area is located within the eco-region of the semiarid Northeast coast, where mangroves occur in small areas and estuaries are affected by mesomareal regimes. The population structure was evaluated by the frequency distribution of size classes in each month, and the overall sex ratio was analyzed using the chi-square test. Size at morphological sexual maturity was estimated based on the allometry of the cheliped of the males and the abdomen width of the females, using the program REGRANS. The size-frequency distribution was unimodal in both sexes. The overall sex ratio (M:F) (1:0.6) was significantly different from 1:1. Analysis of the sex ratio by size class showed that the proportion of males increased significantly from size class 55-60 mm upward, and this pattern persisted in the larger size classes. In the smaller size classes the sex ratio did not differ from 1:1. The size at morphological sexual maturity was estimated at a carapace width (CW) of 52 mm and 45 mm for males and females, respectively. Analysis of the population parameters indicated that the population of U. cordatus in the Jaguaribe River mangrove is stable. However, constant monitoring of the population is required to detect any changes in the population attributes that may affect this stability.

  14. Phylogeography and genetic structure of the oriental river prawn Macrobrachium nipponense (Crustacea: Decapoda: Palaemonidae) in East Asia

    PubMed Central

    Chu, Ta-Jen; Lee, Ying-Chou

    2017-01-01

    The oriental river prawn (Macrobrachium nipponense) is mainly distributed in East Asia. The phylogeography, population genetic structure and historical demography of this species in the East Asia were examined by using partial sequences of the cytochrome oxidase subunit I (COI) and 16S rRNA in mitochondrial DNA. Ten populations that included 239 individuals were collected from Taiwan (Shihmen Reservoir, SMR, Mingte Reservoir, MTR and Chengching Lake Reservoir, CLR), mainland China (Taihu Lake, TLC, Min River, MRC, Jiulong River, JRC and Shenzhen Reservoir, SRC), Japan (Biwa Lake, BLJ and Kasumigaura Lake, KLJ) and Korea (Han River, HRK). The nucleotide diversity (π) of all individuals was 0.01134, with values ranging from 0.0089 (BLJ, Japan) to 0.01425 (MTR, Taiwan). A total of 83 haplotypes were obtained, and the haplotypes were divided into 2 main lineages: lineage A included the specimens from BLJ, KLJ, CLR, MTR, TLC, MRC and JRC, and lineage B comprised the ones from HRK, SRC, SMR, MTR, TLC, MRC and JRC. Lineage A could be further divided two sub-lineages (A1 and A2). Individuals of lineage A2 were only from TLC. Demographic expansion was observed in each lineage, starting within the second-to-latest interglacial period for lineage A and within the last glacial period for lineage B. All FST values among the ten populations were significantly different, except for the values between MRC and JRC, and SMR and SRC. The phylogeography and genetic structure of M. nipponense in East Asia might be influenced by Pleistocene glacial cycles, lake isolation and human introduction. The possible dispersal routes of M. nipponense in the East Asia were also discussed. PMID:28267807

  15. Phylogenetic Diversity, Distribution, and Cophylogeny of Giant Bacteria (Epulopiscium) with their Surgeonfish Hosts in the Red Sea

    PubMed Central

    Miyake, Sou; Ngugi, David K.; Stingl, Ulrich

    2016-01-01

    Epulopiscium is a group of giant bacteria found in high abundance in intestinal tracts of herbivorous surgeonfish. Despite their peculiarly large cell size (can be up to 600 μm), extreme polyploidy (some with over 100,000 genome copies per cell) and viviparity (whereby mother cells produce live offspring), details about their diversity, distribution or their role in the host gut are lacking. Previous studies have highlighted the existence of morphologically distinct Epulopiscium cell types (defined as morphotypes A to J) in some surgeonfish genera, but the corresponding genetic diversity and distribution among other surgeonfishes remain mostly unknown. Therefore, we investigated the phylogenetic diversity of Epulopiscium, distribution and co-occurrence in multiple hosts. Here, we identified eleven new phylogenetic clades, six of which were also morphologically characterized. Three of these novel clades were phylogenetically and morphologically similar to cigar-shaped type A1 cells, found in a wide range of surgeonfishes including Acanthurus nigrofuscus, while three were similar to smaller, rod-shaped type E that has not been phylogenetically classified thus far. Our results also confirmed that biogeography appears to have relatively little influence on Epulopiscium diversity, as clades found in the Great Barrier Reef and Hawaii were also recovered from the Red Sea. Although multiple symbiont clades inhabited a given species of host surgeonfish and multiple host species possessed a given symbiont clade, statistical analysis of host and symbiont phylogenies indicated significant cophylogeny, which in turn suggests co-evolutionary relationships. A cluster analysis of Epulopiscium sequences from previously published amplicon sequencing dataset revealed a similar pattern, where specific clades were consistently found in high abundance amongst closely related surgeonfishes. Differences in abundance may indicate specialization of clades to certain gut environments

  16. The selective cleaning behaviour of juvenile blue-headed wrasse (Thalassoma bifasciatum) in the Caribbean.

    PubMed

    Dunkley, Katie; Cable, Jo; Perkins, Sarah E

    2018-02-01

    Through the removal of parasites, dead skin and mucus from the bodies of visiting reef fish (clients), cleaner fish have a significant ecosystem function in the ecology of coral reefs. Cleaners gain nutrition from these interactions and through offering a 'service' are afforded protection from predators. Given these benefits, it is unclear why more fish do not engage in cleaning, and why part-time cleaning strategies exist. On coral reefs, dedicated species clean throughout their life, whereas some species are facultative, employing opportunistic and/or temporary cleaning strategies. Here, we investigate the cleaning behaviour of a facultative species to assess the relative importance of this interaction to the cleaner. Using a combination of focal and event sampling from a coral reef in Tobago, we show that cleaning is not an essential food source for facultative juvenile blue-headed wrasse (Thalassoma bifasciatum), as cleaning rate was unrelated to their foraging rate on the substrate. These wrasse displayed two cleaning strategies: stationary versus wandering cleaning, with cleaning frequency being highest for stationary cleaners. A specific cleaning location facilitated increased cleaning frequency, and wrasse cleaning rate decreased as cleaner or client abundance increased. We also compared juvenile blue-headed wrasse cleaning behaviour to a resident dedicated cleaner, the sharknose goby (Elacatinus evelynae), and showed that, in comparison, juvenile wrasse clean a narrower client range, predominately cleaning three species of gregarious free-ranging surgeonfish (Acanthurus spp.). The wrasse, however, frequently approached these clients without cleaning, which suggests that their selective cleaning strategy may be driven by the acquisition of a particular parasitic food source. Juvenile blue-headed wrasse are generalist foragers, and may thus be limited in their cleaning behaviour by their nutritional requirements, the availability of a suitable cleaning site

  17. Mesozooplankton community development at elevated CO2 concentrations: results from a mesocosm experiment in an Arctic fjord

    NASA Astrophysics Data System (ADS)

    Niehoff, B.; Schmithüsen, T.; Knüppel, N.; Daase, M.; Czerny, J.; Boxhammer, T.

    2013-03-01

    The increasing CO2 concentration in the atmosphere caused by burning fossil fuels leads to increasing pCO2 and decreasing pH in the world ocean. These changes may have severe consequences for marine biota, especially in cold-water ecosystems due to higher solubility of CO2. However, studies on the response of mesozooplankton communities to elevated CO2 are still lacking. In order to test whether abundance and taxonomic composition change with pCO2, we have sampled nine mesocosms, which were deployed in Kongsfjorden, an Arctic fjord at Svalbard, and were adjusted to eight CO2 concentrations, initially ranging from 185 μatm to 1420 μatm. Vertical net hauls were taken weekly over about one month with an Apstein net (55 μm mesh size) in all mesocosms and the surrounding fjord. In addition, sediment trap samples, taken every second day in the mesocosms, were analysed to account for losses due to vertical migration and mortality. The taxonomic analysis revealed that meroplanktonic larvae (Cirripedia, Polychaeta, Bivalvia, Gastropoda, and Decapoda) dominated in the mesocosms while copepods (Calanus spp., Oithona similis, Acartia longiremis and Microsetella norvegica) were found in lower abundances. In the fjord copepods prevailed for most of our study. With time, abundance and taxonomic composition developed similarly in all mesocosms and the pCO2 had no significant effect on the overall community structure. Also, we did not find significant relationships between the pCO2 level and the abundance of single taxa. Changes in heterogeneous communities are, however, difficult to detect, and the exposure to elevated pCO2 was relatively short. We therefore suggest that future mesocosm experiments should be run for longer periods.

  18. Monitoring an alien invasion: DNA barcoding and the identification of lionfish and their prey on coral reefs of the Mexican Caribbean.

    PubMed

    Valdez-Moreno, Martha; Quintal-Lizama, Carolina; Gómez-Lozano, Ricardo; García-Rivas, María Del Carmen

    2012-01-01

    In the Mexican Caribbean, the exotic lionfish Pterois volitans has become a species of great concern because of their predatory habits and rapid expansion onto the Mesoamerican coral reef, the second largest continuous reef system in the world. This is the first report of DNA identification of stomach contents of lionfish using the barcode of life reference database (BOLD). We confirm with barcoding that only Pterois volitans is apparently present in the Mexican Caribbean. We analyzed the stomach contents of 157 specimens of P. volitans from various locations in the region. Based on DNA matches in the Barcode of Life Database (BOLD) and GenBank, we identified fishes from five orders, 14 families, 22 genera and 34 species in the stomach contents. The families with the most species represented were Gobiidae and Apogonidae. Some prey taxa are commercially important species. Seven species were new records for the Mexican Caribbean: Apogon mosavi, Coryphopterus venezuelae, C. thrix, C. tortugae, Lythrypnus minimus, Starksia langi and S. ocellata. DNA matches, as well as the presence of intact lionfish in the stomach contents, indicate some degree of cannibalism, a behavior confirmed in this species by the first time. We obtained 45 distinct crustacean prey sequences, from which only 20 taxa could be identified from the BOLD and GenBank databases. The matches were primarily to Decapoda but only a single taxon could be identified to the species level, Euphausia americana. This technique proved to be an efficient and useful method, especially since prey species could be identified from partially-digested remains. The primary limitation is the lack of comprehensive coverage of potential prey species in the region in the BOLD and GenBank databases, especially among invertebrates.

  19. Monitoring an Alien Invasion: DNA Barcoding and the Identification of Lionfish and Their Prey on Coral Reefs of the Mexican Caribbean

    PubMed Central

    Valdez-Moreno, Martha; Quintal-Lizama, Carolina; Gómez-Lozano, Ricardo; García-Rivas, María del Carmen

    2012-01-01

    Background In the Mexican Caribbean, the exotic lionfish Pterois volitans has become a species of great concern because of their predatory habits and rapid expansion onto the Mesoamerican coral reef, the second largest continuous reef system in the world. This is the first report of DNA identification of stomach contents of lionfish using the barcode of life reference database (BOLD). Methodology/Principal Findings We confirm with barcoding that only Pterois volitans is apparently present in the Mexican Caribbean. We analyzed the stomach contents of 157 specimens of P. volitans from various locations in the region. Based on DNA matches in the Barcode of Life Database (BOLD) and GenBank, we identified fishes from five orders, 14 families, 22 genera and 34 species in the stomach contents. The families with the most species represented were Gobiidae and Apogonidae. Some prey taxa are commercially important species. Seven species were new records for the Mexican Caribbean: Apogon mosavi, Coryphopterus venezuelae, C. thrix, C. tortugae, Lythrypnus minimus, Starksia langi and S. ocellata. DNA matches, as well as the presence of intact lionfish in the stomach contents, indicate some degree of cannibalism, a behavior confirmed in this species by the first time. We obtained 45 distinct crustacean prey sequences, from which only 20 taxa could be identified from the BOLD and GenBank databases. The matches were primarily to Decapoda but only a single taxon could be identified to the species level, Euphausia americana. Conclusions/Significance This technique proved to be an efficient and useful method, especially since prey species could be identified from partially-digested remains. The primary limitation is the lack of comprehensive coverage of potential prey species in the region in the BOLD and GenBank databases, especially among invertebrates. PMID:22675470

  20. Transcriptomic analysis of adaptive mechanisms in response to sudden salinity drop in the mud crab, Scylla paramamosain.

    PubMed

    Wang, Huan; Tang, Lei; Wei, Hongling; Lu, Junkai; Mu, Changkao; Wang, Chunlin

    2018-05-31

    Scylla paramamosain (Crustacea: Decapoda: Portunidae: Syclla De Hann) is a commercially important mud crab distributed along the coast of southern China and other Indo-Pacific countries (Lin Z, Hao M, Zhu D, et al, Comp Biochem Physiol B Biochem Mol Biol 208-209:29-37, 2017; Walton ME, Vay LL, Lebata JH, et al, Estuar Coast Shelf Sci 66(3-4):493-500, 2006; Wang Z, Sun B, Zhu F, Fish Shellfish Immunol 67:612-9, 2017). While S. paramamosain is a euryhaline species, a sudden drop in salinity induces a negative impact on growth, molting, and reproduction, and may even cause death. The mechanism of osmotic regulation of marine crustaceans has been recently under investigation. However, the mechanism of adapting to a sudden drop in salinity has not been reported. In this study, transcriptomics analysis was conducted on the gills of S. paramamosain to test its adaptive capabilities over 120 h with a sudden drop in salinity from 23 ‰ to 3 ‰. At the level of transcription, 135 DEGs (108 up-regulated and 27 down-regulated) annotated by NCBI non-redundant (nr) protein database were screened. GO analysis showed that the catalytic activity category showed the most participating genes in the 24 s-tier GO terms, indicating that intracellular metabolic activities in S. paramamosain were enhanced. Of the 164 mapped KEGG pathways, seven of the top 20 pathways were closely related to regulation of the Na + / K + -ATPase. Seven additional amino acid metabolism-related pathways were also found, along with other important signaling pathways. Ion transport and amino acid metabolism were key factors in regulating the salinity adaptation of S. paramamosain in addition to several important signaling pathways.

  1. Teretamon spelaeum, a new species of freshwater crab (Crustacea: Decapoda: Potamidae) from a limestone cave in Meghalaya, India.

    PubMed

    Absar, Parveen Farzana; Mitra, Santanu; Kharkongor, Ilona Jacinta

    2017-12-18

    A new species of freshwater crab of the genus Teretamon Yeo Ng, 2007 is described based on material collected from a limestone cave state of Meghalaya, in the northeastern Himalayan region of India. Teretamon spelaeum n. sp. can easily be distinguished from its congeners by a well suite of carapace and gonopod characters: a relatively wider carapace, setose chelipeds and legs, a highly reduced cornea of the eye, and a diagnostic male first gonopod that has a low rounded median dorsal flap on the terminal joint. The morphology of the new species is clearly adapted for the cave dwelling and is the first true troglobitic freshwater crab known from India.

  2. Towards a Supertree of Arthropoda: A Species-Level Supertree of the Spiny, Slipper and Coral Lobsters (Decapoda: Achelata)

    PubMed Central

    Davis, Katie E.; Hesketh, Thomas W.; Delmer, Cyrille; Wills, Matthew A.

    2015-01-01

    While supertrees have been built for many vertebrate groups (notably birds, mammals and dinosaurs), invertebrates have attracted relatively little attention. The paucity of supertrees of arthropods is particularly surprising given their economic and ecological importance, as well as their overwhelming contribution to biodiversity. The absence of comprehensive archives of machine-readable source trees, coupled with the need for software implementing repeatable protocols for managing them, has undoubtedly impeded progress. Here we present a supertree of Achelata (spiny, slipper and coral lobsters) as a proof of concept, constructed using new supertree specific software (the Supertree Toolkit; STK) and following a published protocol. We also introduce a new resource for archiving and managing published source trees. Our supertree of Achelata is synthesised from morphological and molecular source trees, and represents the most complete species-level tree of the group to date. Our findings are consistent with recent taxonomic treatments, confirming the validity of just two families: Palinuridae and Scyllaridae; Synaxidae were resolved within Palinuridae. Monophyletic Silentes and Stridentes lineages are recovered within Palinuridae, and all sub-families within Scyllaridae are found to be monophyletic with the exception of Ibacinae. We demonstrate the feasibility of building larger supertrees of arthropods, with the ultimate objective of building a complete species-level phylogeny for the entire phylum using a divide and conquer strategy. PMID:26461106

  3. Towards a Supertree of Arthropoda: A Species-Level Supertree of the Spiny, Slipper and Coral Lobsters (Decapoda: Achelata).

    PubMed

    Davis, Katie E; Hesketh, Thomas W; Delmer, Cyrille; Wills, Matthew A

    2015-01-01

    While supertrees have been built for many vertebrate groups (notably birds, mammals and dinosaurs), invertebrates have attracted relatively little attention. The paucity of supertrees of arthropods is particularly surprising given their economic and ecological importance, as well as their overwhelming contribution to biodiversity. The absence of comprehensive archives of machine-readable source trees, coupled with the need for software implementing repeatable protocols for managing them, has undoubtedly impeded progress. Here we present a supertree of Achelata (spiny, slipper and coral lobsters) as a proof of concept, constructed using new supertree specific software (the Supertree Toolkit; STK) and following a published protocol. We also introduce a new resource for archiving and managing published source trees. Our supertree of Achelata is synthesised from morphological and molecular source trees, and represents the most complete species-level tree of the group to date. Our findings are consistent with recent taxonomic treatments, confirming the validity of just two families: Palinuridae and Scyllaridae; Synaxidae were resolved within Palinuridae. Monophyletic Silentes and Stridentes lineages are recovered within Palinuridae, and all sub-families within Scyllaridae are found to be monophyletic with the exception of Ibacinae. We demonstrate the feasibility of building larger supertrees of arthropods, with the ultimate objective of building a complete species-level phylogeny for the entire phylum using a divide and conquer strategy.

  4. The population biology and genetics of the deep-sea spider crab, Encephaloides armstrongi Wood-Mason 1891 (Decapoda: Majidae)

    PubMed Central

    Creasey, S.; Rogers, A. D.; Tyler, P.; Young, C.; Gage, J.

    1997-01-01

    Numerous specimens of the majid spider crab, Encephaloides armstrongi, were sampled from six stations (populations) between 150 and 650 m depth, on the continental slope off the coast of Oman. This extended the known geographic and bathymetric range of E. armstrongi, which is now known to occur along the continental margins of the northern Indian Ocean from the western coast of Burma to the coast of Oman. This band-like distribution is contiguous to the oxygen minimum zone in this region. The biology and genetics of populations of Encephaloides armstrongi separated by depth were studied. The overall sex ratio of the E. armstrongi sampled was male-biased (p less than 0.01; 3.3 males: 1 female; So = 0.538). However, sex ratio varied both between populations (p less than 0.01) and between size classes of crabs. Size frequency analysis indicated that the male and female crabs consisted of at least two instars, one between 6 and 16mm carapace length and one between 16 and 29 mm carapace length, which probably represented the terminal (pubertal) moult for most individuals. Accumulation of female crabs in the terminal instar probably caused the variation of sex ratio with size classes. Some male crabs grew to a larger size (up to 38 mm carapace length), possibly as a result of maturity at later instars. Length frequency distribution was significantly different between sexes (one-way ANOVA p less than 0.001). Within sexes, length frequency distributions varied between different populations. In both male and female Encephaloides armstrongi the individuals from a single population located at 150 m depth were significantly smaller than individuals at all other stations and were considered to represent a juvenile cohort. For female crabs no other significant differences were detected in length frequency between populations from 300 m to 650 m depth. Significant differences in length frequency were detected between male crabs from populations between 300 and 650 m depth. Horizontal starch gel electrophoresis was used to detect six enzyme systems coding for eight loci for individuals sampled from each population of Encephaloides armstrongi. Genetic identity (I) values between populations of E. armstrongi (I = 0.98-1.00) were within the normal range for conspecific populations. Observed heterozygosity (Ho = 0.080-0.146) was lower than expected heterozygosity (He = 0.111-0.160), but in the normal range detected for eukaryotic organisms. F-statistics were used to analyse between population (FST) and within population (F ) genetic structure. For both male and female E. armstrongi significant genetic differentiation was detected between the population located at 150 m depth and all other populations. Analyses of FIS and FST, excluding the 150 m population indicated that for female E. armstrongi there was no significant structuring within or between populations. For male E. armstrongi significant heterozygote deficiencies were detected within populations and significant genetic differentiation between populations. The most likely explanations for the observations of the present study are: the population of Encephaloides armstrongi located at 150 m depth represented a juvenile cohort that is genetically distinct from deeper populations; female E. armstrongi formed a single population between 300 m and 650 m depth in the sampling area; male E. armstrongi were from two or more genetically distinct populations which are represented by different numbers of individuals at stations between 300 m and 650 m depth. This caused the observed significant differences in morphology (size distribition) and allele frequencies of male populations. It is likely that E. armstrongi exhibits gender-biased dispersal and that the crabs collected between 300 m and 650 m depth formed spawning aggressions. This also explains the bias in sex ratio of individuals sampled in the present study.

  5. A New Species of the Genus Kiwa (Decapoda: Anomura) from the Hydrothermal Vent of the Australia-Antarctic Ridge

    NASA Astrophysics Data System (ADS)

    Won, Y. J.; Lee, S. H.; Lee, W. K.

    2014-12-01

    Due to extreme weather conditions and remoteness to access, the great part of the Southern Ocean remains to be explored. Therefore, little is known about the Circum-Antarctic Ridge (CAR) system and its hydrothermal vent ecosystem underlying the Southern Ocean. We report the first discovery of a new deep-sea hydrothermal vent field and a new anomuran species from the Australia-Antarctic Ridge (AAR), the highest latitude (62°S; 158°E) explored in the Southern Ocean up to date. At this site, a new anomuran species which belongs to the genus Kiwa known as 'yeti crabs' was found. Morphologically, this species has characteristics of the genus Kiwa, including fifth pereopod inserted below sterna plastron, third sternite strongly produced anteriorly, and eyes extremely reduced. However, the new species differs from the other known species of Kiwa, K. hirsuta and K. puravida, showing relatively short rostrum and slender dactylus on second to fourth pereopods. Phylogenetic analysis using DNA sequences of eight genetic loci also supported the result of morphological analysis, confirming this species as a new Kiwa species, Kiwa n. sp. In addition, phylogenetic tree revealed the evolutionary relationship among the Kiwa species, presenting the Kiwa n. sp. as the sister species to K. puravida which inhabits the methane cold seep on the Pacific continental slope off Costa Rica. Considering the geography and the physicochemical environment, this unlikely result casts a mystery to be solved through further taxon sampling particularly from as-yet-unexplored vents and seeps. Discovery of the hydrothermal vent and Kiwa n. sp. from the AAR segment is significant because this site is located in the high latitude of the southern hemisphere and it is the region affected by the Antarctic Circumpolar Current (ACC). Future research on the relation of Kiwa n. sp. and the other Kiwa species affected by the ACC will provide an idea about the biogeography and the evolutionary connections of the vent faunas in the CAR system.

  6. Morphology and ultrastructure of the esophagus during the ontogeny of the spider crab Maja brachydactyla (Decapoda, Brachyura, Majidae).

    PubMed

    Castejón, Diego; Rotllant, Guiomar; Ribes, Enric; Durfort, Mercè; Guerao, Guillermo

    2018-06-01

    The esophagus of the eucrustaceans is known as a short tube that connects the mouth with the stomach but has generally received little attention by the carcinologists, especially during the larval stages. By this reason, the present study is focused on the morphology and ultrastructure of the esophagus in the brachyuran Maja brachydactyla during the larval development and adult stage. The esophagus shows internally four longitudinal folds. The simple columnar epithelium is covered by a thick cuticle. The epithelial cells of the adults are intensively interdigitated and show abundant apical mitochondria and bundles of filamentous structures. The cuticle surface has microspines and mutually exclusive pores. Three muscle layers surrounded by the connective tissue are reported: circular muscles forming a broad continuous band, longitudinal muscle bundles adjacent to the circular muscles, and dilator muscles crossing the connective tissue vertically toward the epithelium. The connective tissue has rosette glands. The esophagus of the larvae have epithelial cells with big vesicles but poorly developed interdigitations and filamentous structures, the cuticle is formed by a procuticle without differentiated exocuticle and endocuticle, the connective layer is thin and the rosette glands are absent. The observed features can be explained by his role in the swallowing of the food. © 2018 Wiley Periodicals, Inc.

  7. Acute toxicity of Roundup® herbicide to three life stages of the freshwater shrimp Caridina nilotica (Decapoda: Atyidae)

    NASA Astrophysics Data System (ADS)

    Mensah, P. K.; Muller, W. J.; Palmer, C. G.

    Glyphosate based herbicides, including Roundup®, are frequently used in the chemical control of weeds and invading alien plant species in South Africa. These herbicides ultimately get into water courses directly or indirectly through processes such as drifting, leaching, surface runoff and foliar spray of aquatic nuisance plants. Despite their widespread use, no water quality guideline exists to protect indigenous South African freshwater organisms from the toxic effects of these herbicides. The toxicity of the herbicide Roundup® was assessed using three different life stages of the freshwater shrimp Caridina nilotica, a prevalent species in South African freshwater ecosystems. Neonate (<7 days post hatching (dph)), juvenile (>7 dph and <20 dph) and adult (>40 dph) shrimps were exposed to varying concentrations (1.5-50 mg/L acid equivalence (a.e.)) of the herbicide in 48 and 96 h acute toxicity tests in order to determine the most sensitive life-stage. The results showed neonates to be more sensitive to Roundup® than both juveniles and adults with mean 96 h LC 50 values of 2.5, 7.0 and 25.3 mg/L a.e. respectively. The estimated 96 h LC 50 of neonates is much lower than the application rate (20-30 mg/L a.e.), although the application’s impact will depend on the dilution rate of the applied concentration in the environment. All three life-stages of unexposed animals exhibited active and coordinated movement but exposed shrimps were erratic and slow in their movements, with neonates showing most of these behavioral irregularities. This study shows that low levels of the herbicide Roundup® may adversely affect C. nilotica health and survival. Thus, the herbicide should be carefully managed to minimize any negative impact on non-target freshwater organisms.

  8. The effect of astaxanthin on resistance of juvenile prawns Macrobrachium nipponense (Decapoda: Palaemonidae) to physical and chemical stress.

    PubMed

    Tizkar, Babak; Seidavi, Alireza; Ponce-Palafox, Jesús Trinidad; Pourashoori, Parastoo

    2014-12-01

    In recent years, the use of new scientific techniques has effectively improved aquaculture production processes. Astaxanthin has various properties in aquaculture and its antioxidant benefits have been closely related to stress resistance; besides, it is an essential factor for growth in many crustaceans and fish. The objective of this study was to evaluate the resistance of prawn (Macrobrachium nipponense) fed diets containing different amounts of astaxanthin (AX) to the shock and stress of different physicochemical environments. A 70-day trial was conducted to evaluate the effect of supplementation of a source of astaxanthin (Carophyll Pink, 10% astaxanthin, w/w, Hoffman-La Roche, Switzerland) at various levels in the diet of M. nipponense juveniles. Four dry diets were prepared: AX0 without astaxanthin, AX50 with 50 mg/kg, AX100 with 100 mg/kg, and AX150 with 150 mg/kg astaxanthin. The feeding trial was conducted in a recirculation water system consisting of 12 fiberglass tanks (1000L) used for holding prawns. Three replicate aquaria were initially stocked with 36 org/m2 per tank. During the trial, prawns were maintained on a 12:12-h light:dark photoperiod with an ordinary incandescent lamp, and the water quality parameters were maintained as follows: water temperature, 25-26°C; salinity, 1 g/L; pH, 8.5-8.8; dissolved oxygen, 6.0-6.5 mg/L; and ammonia-nitrogen, 0.05 mg/L. Incorporation of AX, production output, and physiological condition were recorded after 10 weeks of feeding. At the end of the growing period, the prawns were exposed to thermal shock (0°C), ammonia (0.75 mg/L), and reduced oxygen (0.5 mg/L). The time to lethargy and the time to complete death of the prawns were recorded. The results showed that control prawns had the shortest time to lethargy and death compared with prawns subjected to the other treatments. The results of this study have shown that the amount of muscle tissue and gill carotenoids in prawn fed with an AX150 diet showed greater reduction than those exposed to other treatments. It is possible that higher levels of astaxanthin in the body under oxygen reduction stress can be beneficial for prawns. These results suggest that male prawns showed lethargy earlier than females, and the percentage of carotenoid reduction in muscle and gill tissues was higher in males.

  9. Further records of the deep-sea pandalid shrimp Heterocarpus chani Li, 2006 (Crustacea, Decapoda, Caridea) from southern India

    PubMed Central

    Yang, Chien-Hui; Kumar, Appukuttannair Biju; Chan, Tin-Yam

    2017-01-01

    Abstract The commercial deep-sea caridean shrimp Heterocarpus gibbosus Spence Bate, 1888 has long been recorded from India and constitutes an important part of the catches in the context of the further development of deep-sea fisheries in India. A recent survey in some deep-sea fishing ports in southern India, however, revealed that all material previously reported as “H. gibbosus” is actually a misidentification of its closely related species H. chani Li, 2006, which has only recently been reported from India. More detailed comparisons allowed the discovery of more distinctive characters between H. chani and H. gibbosus. PMID:29089843

  10. A new species of the ghost shrimp genus Lepidophthalmus (Crustacea: Decapoda: Axiidea) from the southwestern Gulf of Mexico.

    PubMed

    Felder, Darryl L

    2015-07-13

    A new species of Lepidophthalmus lacking a ventral median sclerite on the second abdominal somite is described from coastal waters of the southwestern Gulf of Mexico. Lepidophthalmus statoni sp. nov., originally recognized only as a unique population in allozyme studies, is sympatric with the ventrally plated species Lepidophthalmus manningi Felder & Staton, 2000, but more closely resembles Lepidophthalmus louisianensis (Schmitt, 1935) from the northern and northwestern Gulf of Mexico. Apparently restricted to intertidal and shallow subtidal tropical waters, the new species is known to range from western Campeche to middle-upper reaches of Veracruz, Mexico. As many members of the genus, it commonly inhabits euryhaline inlets, estuaries, and protected shorelines, including richly organic muddy to clayey sands and sandy muds adjacent to shoreline vegetation. Coloration is documented and discussed as a tool to facilitate field identifications, as are morphological characters.

  11. Use of multiple chemical tracers to define habitat use of Indo-Pacific mangrove crab, Scylla serrata (Decapoda: Portunidae)

    USGS Publications Warehouse

    Demopoulos, A.W.J.; Cormier, N.; Ewel, K.C.; Fry, B.

    2008-01-01

    The mangrove or mud crab, Scylla serrata, is an important component of mangrove fisheries throughout the Indo-Pacific. Understanding crab diets and habitat use should assist in managing these fisheries and could provide additional justification for conservation of the mangrove ecosystem itself. We used multiple chemical tracers to test whether crab movements were restricted to local mangrove forests, or extended to include adjacent seagrass beds and reef flats. We sampled three mangrove forests on the island of Kosrae in the Federated States of Micronesia at Lelu Harbor, Okat River, and Utwe tidal channel. Samples of S. serrata and likely food sources were analyzed for stable carbon (??13C), nitrogen (??15N), and sulfur (??34S) isotopes. Scylla serrata tissues also were analyzed for phosphorus (P), cations (K, Ca, Mg, Na), and trace elements (Mn, Fe, Cu, Zn, and B). Discriminant analysis indicated that at least 87% of the crabs remain in each site as distinct populations. Crab stable isotope values indicated potential differences in habitat use within estuaries. Values for ??13C and ??34S in crabs from Okat and Utwe were low and similar to values expected from animals feeding within mangrove forests, e.g., feeding on infauna that had average ??13C values near -26.5???. In contrast, crabs from Lelu had higher ?? 13C and ??34S values, with average values of -21.8 and 7.8???, respectively. These higher isotope values are consistent with increased crab foraging on reef flats and seagrasses. Given that S. serrata have been observed feeding on adjacent reef and seagrass environments on Kosrae, it is likely that they move in and out of the mangroves for feeding. Isotope mixing model results support these conclusions, with the greatest mangrove ecosystem contribution to S. serrata diet occurring in the largest mangrove forests. Conserving larger island mangrove forests (> 1 km deep) appears to support crab foraging activities. ?? 2007 Coastal and Estuarine Research Federation.

  12. Periclimenes macrorhynchia sp. nov., a new hydrozoan-associated pontoniine shrimp (Crustacea, Decapoda, Palaemonidae) from North East Kalimantan, Indonesia.

    PubMed

    Eilbracht, Joni; Fransen, Charles H J M

    2015-08-03

    A new species of pontoniine shrimp belonging to the 'Periclimenes obscurus species group' is described from the Berau Islands, North East Kalimantan, Indonesia. Specimens were obtained from aglaopheniid hydrozoans of the genus Macrorhynchia. The new species is here described and figured. Its affinities with related species are discussed and a DNA-barcode is provided.

  13. Seasonal differences in the physiology of Carcinus maenas (Crustacea: Decapoda) from estuaries with varying levels of anthropogenic contamination

    NASA Astrophysics Data System (ADS)

    Dissanayake, Awantha; Galloway, Tamara S.; Jones, Malcolm B.

    2011-07-01

    This study reports the seasonal variability in aspects of the physiology of the shore crab Carcinus maenas from three estuaries in South-west England, each with varying anthropogenic inputs: Avon Estuary ('relatively low' impact), Yealm Estuary ('intermediate' impact) and Plym Estuary ('relatively high' impact). Crabs collected over 12 months from the Avon had a significantly 'lower' physiological condition in winter and spring compared to summer and autumn; in particular, haemocyte phagocytic capability (a general indicator of immune function) was significantly higher in winter and spring compared to summer and autumn, and total haemolymph antioxidant status (an indicator of oxidative stress) was significantly lower in winter compared to the remainder of the year. Potentially, shore crabs may be more susceptible to the effects of contaminant exposure, such as increased immunotoxicity (thus, reduction of immune function) and/or oxyradicals (or reactive oxygen species) exposure) especially in seasons of increased susceptibility i.e. summer/autumn (lower phagocytic capability) and winter (lowest antioxidant function). As the Avon was taken to represent the 'reference' site, this pattern is considered to reflect the 'normal' seasonal variability in shore crab physiology. Shore crab physiological condition from the 'relatively high' impact estuary (Plym) revealed increased cellular viability and antioxidant status in autumn and winter compared with that of the 'standard' pattern (Avon) However, crabs from the intermediate impact estuary (Yealm) only demonstrated significant physiological differences in summer as shown by a lower cellular viability. All crabs had been exposed to PAHs (confirmed by the presence of PAH metabolites in their urine) which may account for the observed differences in shore crab physiology. In conclusion, to aid understanding of the potential contaminant impacts on biota it is imperative that the 'normal' seasonal variability of physiological condition be established. Biological effects-based monitoring studies should therefore be employed seasonally to potentially highlight 'windows of sensitivity' to contaminant impact.

  14. The connection between iron ore formations and "mud-shrimp" colonizations around sunken wood debris and hydrothermal sediments in a Lower Cretaceous continental rift basin, Mecsek Mts., Hungary

    NASA Astrophysics Data System (ADS)

    Jáger, Viktor; Molnár, Ferenc; Buchs, David; Koděra, Peter

    2012-09-01

    In the Early Cretaceous, the continental rift basin of the Mecsek Mts. (Hungary), was situated on the southern edge of the European plate. The opening of the North Atlantic Ocean created a dilatational regime that expanded to the southern edge of the European plate, where several extensional basins and submarine volcanoes were formed during the Early Cretaceous epoch. Permanent seaquake activity caused high swell events during which a large amount of terrestrial wood fragments entered into submarine canyons from rivers or suspended woods which had sunk into the deep seafloor. These fragments created extended wood-fall deposits which contributed large-scale flourishing of numerous burrowing thalassinid crustaceans. Twelve different thalassinid coprolite ichnospecies can be found in the Berriasian-Hauterivian volcano-sedimentary formations. According to the seladonitic crustacean burrows which associated with framboidal pyrite containing Zoophycos and Chondrites ichnofossils (i.e. a "fodinichnia" trace fossil association), the bottom water was aerobic and the pore water was anaerobic; in the latter sulfate reduction occurred. The preservation of wood fragments around thalassinid burrows can be explained by rapid sedimentation related to turbidity currents. Due to the low temperature hydrothermal circulations of seawater, large amounts of iron were released from intrusive, pillowed basaltic sills; these sills intruded into soft, water-saturated sediments containing large amounts of thalassinid excrement. In the coprolites can be found idiomorphic mineral particles originating from the basalts, and coprolites can often be found in peperitic interpillow sediments. This indicates that the life-activity of the decapoda crustaceans in many Lower Cretaceous occurrences initially preceded the first magmatic eruptions. The paroxysm of the rift volcanism took place during the Valanginian age, when some submarine volcanoes emerged above sea level, reaching a maximum height of

  15. Vitellogenin levels in hemolymph, ovary and hepatopancreas of the freshwater crayfish Cherax quadricarinatus (Decapoda: Parastacidae) during the reproductive cycle.

    PubMed

    Ferré, Lilian E; Medesani, Daniel A; García, C Fernando; Grodzielski, Matías; Rodríguez, Enrique M

    2012-03-01

    The freshwater crayfish Cherax quadricarinatus is a tropical species of great interest for aquaculture. Vitellogenin (Vg), a lipoprotein precursor of the vitellum accumulated in spawned eggs, can be synthesized in the ovary and/or hepatopancreas of most crustaceans, being the hemolymph the way for transporting Vg throughout the reproductive cycle. Concentration of Vg in hemolymph, ovary and hepatopancreas of Cherax quadricarinatus adult females was measured by means of ELISA, specifically developed after purifying the native Vg. Measurements were made at four periods of the reproductive cycle: pre-reproductive, mid-reproductive, late reproductive and post-reproductive. Besides, both hepatosomatic (HSI) and gonadosomatic (GSI) indexes were determined in each period. Significant variations in Vg levels were detected in both hemolymph and hepatopancreas, being the highest values observed during the mid-reproductive period. Besides, such variations were positively correlated to the HSI. A positive correlation between Vg levels in hepatopancreas and ovary was also seen. These results support previous evidences about the central role of the hepatopancreas as a site of Vg synthesis in the studied species, together with the relevancy of hemolymph for transporting Vg from the hepatopancreas to the ovary. For aquaculture purposes, Vg monitoring in hemolymph could be used as a non-injurious method, to check the reproductive activity of C. quadricarinatus females.

  16. Morphology of the megalopa of the mud crab, Rhithropanopeus harrisii (Gould, 1841) (Decapoda, Brachyura, Panopeidae), identified by DNA barcode

    NASA Astrophysics Data System (ADS)

    Marco-Herrero, Elena; González-Gordillo, J. Ignacio; Cuesta, José A.

    2014-06-01

    The morphology of the megalopa stage of the panopeid Rhithropanopeus harrisii is redescribed and illustrated in detail from plankton specimens identified by DNA barcode (16S mtDNA) as previous descriptions do not meet the current standard of brachyuran larval description. Several morphological characters vary widely from those of other panopeid species which could cast some doubt on the species' placement in the same family. Besides, some anomalous megalopae of R. harrisii were found among specimens reared at the laboratory from zoeae collected in the plankton. These anomalous morphological features are discussed in terms of problems associated with laboratory rearing conditions.

  17. Postsettlement growth of two estuarine crab species, Chasmagnathus granulata and Cyrtograpsus angulatus (Crustacea, Decapoda, Grapsidae): laboratory and field investigations

    NASA Astrophysics Data System (ADS)

    Luppi, T. A.; Spivak, E. D.; Anger, K.

    2002-02-01

    The estuarine grapsid crabs Chasmagnathus granulata and Cyrtograpsus angulatus belong to the most typical and dominant inhabitants of brackish coastal lagoons in southeastern South America. In a combined laboratory and field investigation of juvenile growth, we measured the increase in body size in these species under controlled conditions as well as in field experiments (in Mar Chiquita lagoon, Argentina), seasonal changes in size frequency distribution of a natural population, and growth related changes in selected morphometric traits of male and female juveniles (relations between carapace width, carapace length, propodus height and length of the cheliped, and pleon width). At 24°C, Cy. angulatus grew faster than Ch. granulata; it reached the crab-9 instar (C9; 13 mm carapace width) after 92 days, while Ch. granulata required 107 days to reach the C8 instar (7.4 mm). At 12°C, growth ceased in both species. The pleon begins to show sexual differences in the C5 ( Cy. angulatus) and C8 instar ( Ch. granulata), respectively, while the chelae differentiate earlier in Ch. granulata than in Cy. angulatus (in C4 vs C6). In the field, growth was maximal in summer, and was generally faster than in laboratory cultures. However, there is great individual variability in size (about 25% even in the first crab instar) and in size increments at ecdysis, increasing throughout juvenile growth. Our data indicate that, in the field, small-scale and short-term variations in feeding conditions, temperature, and salinity account for an extremely high degree of variability in the absolute and relative rates of growth as well as in the time to sexual differentiation.

  18. New distributional records of the stygobitic crayfish Cambarus cryptodytes (Decapoda: Cambaridae) in the Floridan Aquifer System of southwestern Georgia

    USGS Publications Warehouse

    Fenolio, Dante B.; Niemiller, Matthew L.; Gluesenkamp, Andrew G.; Mckee, Anna; Taylor, Steven J.

    2017-01-01

    Cambarus cryptodytes (Dougherty Plain Cave Crayfish) is an obligate inhabitant of groundwater habitats (i.e., a stygobiont) with troglomorphic adaptations in the Floridan aquifer system of southwestern Georgia and adjacent Florida panhandle, particularly in the Dougherty Plain and Marianna Lowlands. Documented occurrences of Dougherty Plain Cave Crayfish are spatially distributed as 2 primary clusters separated by a region where few caves and springs have been documented; however, the paucity of humanly accessible karst features in this intermediate region has inhibited investigation of the species' distribution. To work around this constraint, we employed bottle traps to sample for Dougherty Plain Cave Crayfish and other groundwater fauna in 18 groundwater-monitoring wells that access the Floridan aquifer system in 10 counties in southwestern Georgia. We captured 32 Dougherty Plain Cave Crayfish in 9 wells in 8 counties between September 2014 and August 2015. We detected crayfish at depths ranging from 17.9 m to 40.6 m, and established new county records for Early, Miller, Mitchell, and Seminole counties in Georgia, increasing the number of occurrences in Georgia from 8 to 17 sites. In addition, a new US Geological Survey (USGS) Hydrologic Unit Code 8 (HUC8) watershed record was established for the Spring Creek watershed. These new records fill in the distribution gap between the 2 previously known clusters in Georgia and Jackson County, FL. Furthermore, this study demonstrates that deployment of bottle traps in groundwater-monitoring wells can be an effective approach to presence—absence surveys of stygobionts, especially in areas where surface access to groundwater is limited.

  19. Two new species and new records of Microprosthema Stimpson, 1860 (Crustacea: Decapoda: Stenopodidea: Spongicolidae) from the Indo-West Pacific.

    PubMed

    Saito, Tomomi; Anker, Arthur

    2014-08-28

    Two new species of the spongicolid shrimp genus Microprosthema Stimpson, 1860 are described and illustrated on the basis of material collected recently in Australia and Japan. Type specimens of Microprosthema ningaloo sp. nov. were collected on Ningaloo Reef, Western Australia, whereas type specimens of Microprosthema pallidum sp. nov. were collected on a coral reef off Ishigaki Island, Ryukyu Archipelago, southern Japan. Microprosthema ningaloo sp. nov. and M. pallidum sp. nov. differ from all other species of the genus by a combination of morphological characters, including the gill-exopod formulae, and by their diagnostic colour patterns. This study increases the total number of species described in the genus Microprosthema to 16, nine of them in the Indo-West Pacific. In addition, new records are provided for M. lubricum Saito & Okuno, 2011 (Guam), M. plumicorne (Richters, 1880) (Red Sea, Mariana and Marshall Islands, French Polynesia), M. scabricaudatum (Richters, 1880) (Red Sea, Glorieuses and Tuamotu Islands), and M. validum Stimpson, 1860 (Red Sea, Madagascar, Singapore, French Polynesia), significantly extending their previously known distribution ranges. 

  20. A new species of stygobitic freshwater crab of the genus Rodriguezia Bott, 1969 (Crustacea: Decapoda: Trichodactylidae) from Tabasco, Mexico.

    PubMed

    Alvarez, Fernando; Villalobos, JosÉ Luis

    2018-02-07

    A new species of freshwater crab of the family Trichodactylidae, genus Rodriguezia Bott, 1969 is described from Grutas de Agua Blanca in southern Tabasco, Mexico. Rodriguezia is a genus endemic to northern Chiapas and southern Tabasco, distributed over a small area of 70 km. Rodriguezia adani n. sp., the third species of the genus, occurs north of its two congeners, being stygobitic with obvious adaptations to cave life. It can be distinguished from R. villalobosi, an epigean species, by the absence of eyes, lack of pigmentation and elongation of the pereiopods; and from R. mensabak by having less elongated pereiopods relative to carapace breadth, an extremely reduced ocular peduncle, and a smaller adult size.

  1. Cambarus polypilosus, a new species of stream-dwelling crayfish (Decapoda: Cambaridae) from the Western Highland Rim of Tennessee, USA.

    PubMed

    Loughman, Zachary J; Williams, Bronwyn W

    2018-04-03

    Cambarus polypilosus sp. nov. is a stream-dwelling crayfish endemic to tributaries in the Buffalo and lower Duck River drainage, and a reach of the lower Tennessee River in the Western Highland Rim of West-Central Tennessee, U.S.A. The new species is closely allied to the three members of the former subgenus Glareocola, but can be differentiated from each by a combination of characters, including body size, coloration, spination, setation, and form I male gonopod morphology. Several meristic measurements and ratios also differentiate C. polypilosus sp. nov. from Cambarus friaufi, to which it is morphologically most similar. Cambarus polypilosus sp. nov. appears to be common in cherty gravel and cobble habitats, where it is typically found in interstices at depths of 0.3 m or more below the substrate surface.

  2. Lecithotrophic behaviour in zoea and megalopa larvae of the ghost shrimp Lepidophthalmus siriboia Felder and Rodrigues, 1993 (Decapoda: Callianassidae).

    PubMed

    Abrunhosa, Fernando A; Simith, Darlan J B; Palmeira, Carlos A M; Arruda, Danielle C B

    2008-12-01

    Food supply is considered critical for a successful culturing of decapod larvae. However, some species may present yolk reserve sufficient to complete their larval development without external food supply (known as lecithotrophic larval development). In the present study, two experiments were carried out in order to verify whether the callianassid Lepidophthalmus siriboia have lecithotrophic behaviour or, if they need external food for their larval development: Experiment 1, larvae submitted to an initial feeding period and Experiment 2, larvae submitted to an initial starvation period. High survival rate was observed in both experiments, in which only 2 megalopae and 1 zoea III died. These results strongly suggest that larvae of L. siriboia are lecithotrophic as they have sufficiently large yolk reserve to complete their larval development, while the megalopa stage shows facultative lecithotrophy. The larval periods of each stage of the treatments were quite similar and, despite some significant differences in some larval periods, these can be related probably to larval rearing conditions, abiotic factors or, individual variability of larval health, as well as stress caused to the ovigerous females during embryogenesis.

  3. The description of a new species of the Neotropical land crab genus Gecarcinus Leach, 1814 (Crustacea, Decapoda, Brachyura, Gecarcinidae)

    PubMed Central

    Perger, Robert; Wall, Adam

    2014-01-01

    Abstract In this contribution a new species of the land crab genus Gecarcinus Leach, 1814, from the Neotropical Pacific coast of South America is described and illustrated. In addition to its unique body color, Gecarcinus nobilii sp. n. is distinguished from congeners by a distinctly wider carapace front and differences in the shape of the infraorbital margin. The new species is not isolated from Gecarcinus populations from the Pacific coast of Central America by an insurmountable geographic barrier. Considering the closure of the Panamanian Isthmus as a calibration point for morphological divergence between the trans-isthmian mainland populations of Gecarcinus, the virtual lack of morphological differentiation (other than color) between them and the distinctness of G. nobilii sp. n. suggests that G. nobilii sp. n. evolved from a common ancestor before the Isthmus closed. PMID:25152688

  4. Evolutionary morphology of the organ systems in squat lobsters and porcelain crabs (crustacea: Decapoda: Anomala): an insight into carcinization.

    PubMed

    Keiler, Jonas; Richter, Stefan; Wirkner, Christian S

    2015-01-01

    Porcelain crabs (Porcellanidae) are one of three taxa within anomuran crustaceans (Anomala) which possess a crab-like body form. Curiously, these three lineages evolved this shape independently from true crabs (Brachyura) in the course of the evolutionary process termed carcinization. The entire pleon in porcelain crabs is flexed under the cephalothorax and the carapace is approximately as broad as long. Despite their crab-like habitus, porcelain crabs are phylogenetically nested within squat lobsters (Munidopsidae, Munididae, Galatheidae). With a pleon which is only partly flexed under the cephalothorax and a cephalothorax which is longer than it is broad, squat lobsters represent morphologically intermediate forms between lobster-like and crab-like body shapes. Carcinization has so far mostly been studied with respect to outer morphology; however, it is evident that internal anatomical features are influenced through this change of body shape too. In this paper, the situation in Galatheoidea is elucidated by adding more taxa to existing descriptions of the hemolymph vascular systems and associated structures and organs. Micro-computer tomography and 3D reconstruction provide new insights. Autapomorphic states of various internal anatomical characters are present in nearly all the studied species, also reflecting some degree of anatomical disparity found within Galatheoidea. The ventral vessel system of porcelain crabs differs distinctly from that of squat lobsters. The differences in question are coherent (i.e. structural dependent) with morphological transformations in the integument, such as the shortening of the sternal plastron, which evolved in the course of carcinization. Shifts in the gonads and the pleonal neuromeres are coherent with the loss of the caridoid escape reaction, which in turn is a consequence of carcinization. The arterial transformations, however, are minor compared to other instances of carcinization in anomuran crustaceans since the last common ancestor of squat lobsters and porcelain crabs was already "half carcinized". © 2014 Wiley Periodicals, Inc.

  5. SIFamide peptides in clawed lobsters and freshwater crayfish (Crustacea, Decapoda, Astacidea): a combined molecular, mass spectrometric and electrophysiological investigation.

    PubMed

    Dickinson, Patsy S; Stemmler, Elizabeth A; Cashman, Christopher R; Brennan, Henry R; Dennison, Bobbi; Huber, Kristen E; Peguero, Braulio; Rabacal, Whitney; Goiney, Christopher C; Smith, Christine M; Towle, David W; Christie, Andrew E

    2008-04-01

    Recently, we identified the peptide VYRKPPFNGSIFamide (Val(1)-SIFamide) in the stomatogastric nervous system (STNS) of the American lobster Homarus americanus using matrix-assisted laser desorption/ionization-Fourier transform mass spectrometry (MALDI-FTMS). Given that H. americanus is the only species thus far shown to possess this peptide, and that a second SIFamide isoform, Gly(1)-SIFamide, is broadly conserved in other decapods, including another astacidean, the crayfish Procambarus clarkii, we became interested both in confirming our identification of Val(1)-SIFamide via molecular methods and in determining the extent to which this isoform is conserved within other members of the infraorder Astacidea. Here, we present the identification and characterization of an H. americanus prepro-SIFamide cDNA that encodes the Val(1) isoform. Moreover, we demonstrate via MALDI-FTMS the presence of Val(1)-SIFamide in a second Homarus species, Homarus gammarus. In contrast, only the Gly(1) isoform was detected in the other astacideans investigated, including the lobster Nephrops norvegicus, a member of the same family as Homarus, and the crayfish Cherax quadricarinatus, P. clarkii and Pacifastacus leniusculus, which represent members of each of the extant families of freshwater astacideans. These results suggest that Val(1)-SIFamide may be a genus (Homarus)-specific isoform. Interestingly, both Val(1)- and Gly(1)-SIFamide possess an internal dibasic site, Arg(3)-Lys(4), raising the possibility of the ubiquitously conserved isoform PPFNGSIFamide. However, this octapeptide was not detected via MALDI-FTMS in any of the investigated species, and when applied to the isolated STNS of H. americanus possessed little bioactivity relative to the full-length Val(1) isoform. Thus, it appears that the dodeca-variants Val(1)- and Gly(1)-SIFamide are the sole bioactive isoforms of this peptide family in clawed lobsters and freshwater crayfish.

  6. A new microsporidium, Apotaspora heleios n. g., n. sp., from the Riverine grass shrimp Palaemonetes paludosus (Decapoda: Caridea: Palaemonidae).

    PubMed

    Sokolova, Yuliya Y; Overstreet, Robin M

    2018-05-19

    We report a new microsporidium from a key species of the estuarine communities of the Gulf States, the Riverine grass shrimp, Palaemonetes paludosus. A milky-white shrimp was found in the Mobile Bay Delta, a large, oligohaline-freshwater wetland in Alabama, USA. Light microscopy of smears and thick sections of the abdominal tissues demonstrated infection with microsporidian spores enclosed in sporophorous vesicles (SVs) in sets of eight. Broadly oval spores measured 2.9 ± 0.06 × 1.7 ± 0.03 µm (2.5-3.3 × 1.6-1.9 µm, n = 11). SVs with a persistent membrane ranged from 4.4 to 5.6 µm in diameter. Subcuticular epithelium and underlying musculature were packed with sporonts, sporoblasts, and spores. Electron microscopy demonstrated diplokaryotic meronts that gave rise to sporont mother cells with a large single nucleus. The meront plasma membrane turned into a SV envelope, and the sporont wall segregated internally. The sporont nucleus underwent meiosis followed by two mitotic divisions accompanied by internal budding to produce four sporonts, each dividing in two uninucleate sporoblasts. Eight-spore SVs were filled with fibrillary-tubular secretions. Spores possessed 90-110-nm thick envelopes (exospore, 40-60 nm + endospore, 30-50 nm), a triangle-shaped nucleus, isofilar polar filament of 10-13 coils arranged in two-three rows, bipartite polaroplast, and a mushroom-shaped polar disk. The SSU rDNA sequence of the novel species was deposited in GenBank under Accession number MG 708238. SSU rDNA-based phylogenetic analysis indicated that the Riverine grass shrimp microsporidium was a new species and placed it in one branch with two species of Potaspora, xenoma-forming microsporidia from freshwater perciform fishes. Because morphological and developmental characters of the novel species did not fit the diagnosis of the genus Potaspora, and, based on SSU rDNA-inferred phylogenetic analyses, different host specificity, pathogenesis, and ecological considerations, we erect here the new genus Apotaspora for the Riverine grass shrimp microsporidium and name the new species Apotaspora heleios. Grouping together fish and crustacean parasites on SSU rDNA phylogenetic trees suggests that polyxenous life cycles might be a common feature of extinct and/or extant members of the studied lineage of the Microsporidia. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Ultrastructure of spermatozoa of spider crabs, family Mithracidae (Crustacea, Decapoda, Brachyura): Integrative analyses based on morphological and molecular data.

    PubMed

    Assugeni, Camila de O; Magalhães, Tatiana; Bolaños, Juan A; Tudge, Christopher C; Mantelatto, Fernando L; Zara, Fernando J

    2017-12-01

    Recent studies based on morphological and molecular data provide a new perspective concerning taxonomic aspects of the brachyuran family Mithracidae. These studies proposed a series of nominal changes and indicated that the family is actually represented by a different number and representatives of genera than previously thought. Here, we provide a comparative description of the ultrastructure of spermatozoa and spermatophores of some species of Mithracidae in a phylogenetic context. The ultrastructure of the spermatozoa and spermatophore was observed by scanning and transmission electron microscopy. The most informative morphological characters analysed were thickness of the operculum, shape of the perforatorial chamber and shape and thickness of the inner acrosomal zone. As a framework, we used a topology based on a phylogenetic analysis using mitochondrial data obtained here and from previous studies. Our results indicate that closely related species share a series of morphological characteristics of the spermatozoa. A thick operculum, for example, is a feature observed in species of the genera Amphithrax, Teleophrys, and Omalacantha in contrast to the slender operculum observed in Mithraculus and Mithrax. Amphithrax and Teleophrys have a rhomboid perforatorial chamber, while Mithraculus, Mithrax, and Omalacantha show a wider, deltoid morphology. Furthermore, our results are in agreement with recently proposed taxonomic changes including the separation of the genera Mithrax (previously Damithrax), Amphithrax (previously Mithrax) and Mithraculus, and the synonymy of Mithrax caribbaeus with Mithrax hispidus. Overall, the spermiotaxonomy of these species of Mithracidae represent a novel set of data that corroborates the most recent taxonomic revision of the family and can be used in future taxonomic and phylogenetic studies within this family. © 2017 Wiley Periodicals, Inc.

  8. A new species of troglobitic crab of the genus Stygothelphusa Ng, 1989, from Sarawak, Malaysia (Crustacea: Decapoda: Brachyura: Gecarcinucidae).

    PubMed

    Ng, Peter K L; Grinang, Jongkar

    2014-03-04

    A new species of cave crab, Stygothelphusa antu new species, is described from limestone formations in Temurang, Sarawak, Malaysia. The new species is the most highly adapted to a cavericolous lifestyle among the four known species of Stygothelphusa, having a pale body pigmentation, reduced eyes and elongated pereopods. In contrast, the other three species have normal eyes that almost completely fill the orbits. The new species also differs from its congeners by a number of carapace, pereopod and gonopod characters.

  9. The asian decapod Hemigrapsus penicillatus (de Haan, 1835) (Grapsidae, Decapoda) introduced in European waters: status quo and future perspective

    NASA Astrophysics Data System (ADS)

    Gollasch, S.

    1998-09-01

    The Asian decapod Hemigrapsus penicillatus (de Haan, 1835) was first recorded in European waters in 1994. The first specimens were collected in the estuary of Charente Maritime on the west coast of France close to La Rochelle. The current range in Europe covers Spanish shallow water habitats of the Bay of Biscay to areas north of La Rochelle (France). Densities of up to 20 specimens per square metre occur. This species has a high temperature and salinity tolerace and will expand its distribution in European waters. It is not clear whether this crab was introduced by shipping in ballast water or as a fouling organism. Based on a study of ship hull fouling in German dry docks this account provides evidence that hull fouling is a likely vector for the introduction of this crab. In August 1993, six juvenile specimens of H. penicillatus were removed from the hull of a car-carrier. After its journey from Japan into European waters this vessel docked in the port of Bremerhaven (Germany) for a routine inspection and coating with antifouling paint.

  10. Spatio-temporal variations in the diversity and abundance of commercially important Decapoda and Stomatopoda in subtropical Hong Kong waters

    NASA Astrophysics Data System (ADS)

    Lui, Karen K. Y.; Ng, Jasmine S. S.; Leung, Kenneth M. Y.

    2007-05-01

    In subtropical Hong Kong, western waters (WW) are strongly influenced by the freshwater input from the Pearl River estuary, especially during summer monsoon, whereas eastern waters (EW) are predominantly influenced by oceanic currents throughout the year. Such hydrographical differences may lead to spatio-temporal differences in biodiversity of benthic communities. This study investigated the diversity and abundance of commercially important decapods and stomatopods in EW (i.e. Tolo Harbour and Channel) and WW (i.e. Tuen Mun and Lantau Island) of Hong Kong using monthly trawl surveys (August 2003-May 2005). In total, 22 decapod and nine stomatopod species were recorded. The penaeid Metapenaeopsis sp. and stomatopod Oratosquillina interrupta were the most abundant and dominant crustaceans in EW and WW, respectively. Both univariate and multivariate analyses showed that WW supported significantly higher abundance, biomass and diversity of crustaceans than EW, although there were significant between-site and within-site variations in community structure. Higher abundance and biomass of crustaceans were recorded in summer than winter. Such spatio-temporal variations could be explained by differences in the hydrography, environmental conditions and anthropogenic impacts between the two areas. Temporal patterns in the abundance-biomass comparison curves and negative W-statistics suggest that the communities have been highly disturbed in both areas, probably due to anthropogenic activities such as bottom trawling and marine pollution.

  11. [Sex ratio and environmental influence on population growth rate of Callinectes bellicosus (Decapoda: Portunidae) in the Gulf of California].

    PubMed

    Rodríguez-Félix, Demetrio; Cisneros-Mata, Miguel Angel; Aragón-Noriega, Eugenio Alberto; Arreola-Lizárraga, José Alfredo

    2016-09-01

    The brown swimming crab (Callinectes bellicosus) is an economically important species in the Gulf of California, and its fishing activity, held in Sonora from 1986, has been affected by a 20-year declining trend in its biomass. With the aim to understand the possible reasons of this species population changes along time, we estimated population growth rate (r) and sex ratio of C. bellicosus, and combined them with three parameters describing its habitat: sea temperature, wetland extension and habitat size in four areas along the coast of Sonora. For this, monthly mean sex ratio was estimated from crabs samples obtained from commercial catches during 1998-2002 and 2012; mean sea surface temperature for the spawning period (May-August) were derived from remote sensors for the same years; while wetland coverages were obtained from published reports, and habitat size was estimated as the fishing surface. For each area, r was estimated using a method developed for limited data situations using commercial landings (t) from 1986-2013. With data from the four areas, simple and multiple linear regression models were developed to ascertain theoretical sensitivities of r to variations in sex ratio and environmental parameters. A total of 24 556 crabs were sampled; males dominated (68.8 %) over females during the study period and in all areas; a cluster analysis identified two groups according to sex ratio: a Northern group with zones 1 and 2, and a Southern group with zones 3 and 4. r values were different in all zones (P<0.001) as was sex ratio (P=0.037); no differences in temperature were identified within the study years (P>0.995). Both the estimated data and sensitivity analyses suggest the existence of a direct and positive dependence of r on the proportion of female crabs and wetland size. We hypothesize that excess fishing of females caused the declining biomass trend of the brown swimming crab in Sonora, and concluded on the convenience of implementing harvest refugia inside coastal wetlands to protect females during the spawning season.

  12. [Spatio-temporal variation of the ichthyofauna in Xel-Ha, Mexican Caribbean Marine Park and its relationship to physico-chemical parameters].

    PubMed

    Aldana Moreno, Alejandro; Montero Muñoz, Jorge; Aldana Aranda, Dalila

    2016-12-01

    Xel-Ha is a private marine park where the extraction of flora and fauna is not allowed. Here, reef fish are one of the main touristic attractions, but there are no published surveys focused on fish community in this site. In this study we analyzed the spatio-temporal variation of the fish community in different areas of the marine park Xel-Há. Abundance and richness were estimated during one-year period (2012-2013); visual censuses using fixed transects of 100x5 m each distributed in 21 transects along five sites were established in different zones: “Bocana”, “Center”, “North branch”, “Cave” and “River”, including the inlet mouth to the sea, brackish mangrove channels and a zone with freshwater influence. To characterize the fish community, we used species richness, abundance, diversity, and density compared among zones and climatic seasons (rain, “norths” and dry). The similarity among zones and seasons was estimated using a multidimensional scaling analysis. The replacement on the species composition among seasons and sites was realized based on the presence-absence of fish. The influence of physicochemical variables such as temperature, salinity and dissolve oxygen concentration in the fish community was estimated by a principal component analysis. A total of 22 641 individuals were recorded corresponding to sixty-three species over the year. Abundance was higher during the windy season (locally named “norths”) with 7 991 organisms. The most representative species according with abundance and frequency of occurrence were: Haemulon sciurus, H. flavolineatum, Lutjanus griseus, Acanthurus coeruleus, Abudefduf saxatilis, and Gerres cinereus. Diversity increased from the rainy to the dry season; species richness and diversity was lower in “River” than other sites in Xel-Ha. Most species (54 %) species were residents through the year. Four non-shared species were observed during the rainy season and three in dry season. Dissolved

  13. Surgeons and suture zones: Hybridization among four surgeonfish species in the Indo-Pacific with variable evolutionary outcomes.

    PubMed

    DiBattista, Joseph D; Whitney, Jonathan; Craig, Matthew T; Hobbs, Jean-Paul A; Rocha, Luiz A; Feldheim, Kevin A; Berumen, Michael L; Bowen, Brian W

    2016-08-01

    Closely related species can provide valuable insights into evolutionary processes through comparison of their ecology, geographic distribution and the history recorded in their genomes. In the Indo-Pacific, many reef fishes are divided into sister species that come into secondary contact at biogeographic borders, most prominently where Indian Ocean and Pacific Ocean faunas meet. It is unclear whether hybridization in this contact zone represents incomplete speciation, secondary contact, an evolutionary dead-end (for hybrids) or some combination of the above. To address these issues, we conducted comprehensive surveys of two widely-distributed surgeonfish species, Acanthurus leucosternon (N=141) and A. nigricans (N=412), with mtDNA cytochrome b sequences and ten microsatellite loci. These surgeonfishes are found primarily in the Indian and Pacific Oceans, respectively, but overlap at the Christmas and Cocos-Keeling Islands hybrid zone in the eastern Indian Ocean. We also sampled the two other Pacific members of this species complex, A. achilles (N=54) and A. japonicus (N=49), which are known to hybridize with A. nigricans where their ranges overlap. Our results indicate separation between the four species that range from the recent Pleistocene to late Pliocene (235,000-2.25million years ago). The Pacific A. achilles is the most divergent (and possibly ancestral) species with mtDNA dcorr≈0.04, whereas the other two Pacific species (A. japonicus and A. nigricans) are distinguishable only at a population or subspecies level (ΦST=0.6533, P<0.001). Little population structure was observed within species, with evidence of recent population expansion across all four geographic ranges. We detected sharing of mtDNA haplotypes between species and extensive hybridization based on microsatellites, consistent with later generation hybrids but also the effects of allele homoplasy. Despite extensive introgression, 98% of specimens had concordance between mtDNA lineage and

  14. The implications of a Silurian and other thylacocephalan crustaceans for the functional morphology and systematic affinities of the group

    PubMed Central

    2014-01-01

    Background Thylacocephala is a group of enigmatic extinct arthropods. Here we provide a full description of the oldest unequivocal thylacocephalan, a new genus and species Thylacares brandonensis, which is present in the Silurian Waukesha fauna from Wisconsin, USA. We also present details of younger, Jurassic specimens, from the Solnhofen lithographic limestones, which are crucial to our interpretation of the systematic position of Thylacocephala. In the past, Thylacocephala has been interpreted as a crustacean ingroup and as closely related to various groups such as cirripeds, decapods or remipeds. Results The Waukesha thylacocephalan, Thylacares brandonensis n. gen. n. sp., bears compound eyes and raptorial appendages that are relatively small compared to those of other representatives of the group. As in other thylacocephalans the large bivalved shield encloses much of the entire body. The shield lacks a marked optical notch. The eyes, which project just beyond the shield margin, appear to be stalked. Head appendages, which may represent antennulae, antennae and mandibles, appear to be present. The trunk is comprised of up to 22 segments. New details observed on thylacocephalans from the Jurassic Solnhofen lithographic limestones include antennulae and antennae of Mayrocaris bucculata, and endites on the raptorial appendages and an elongate last trunk appendage in Clausocaris lithographica. Preserved features of the internal morphology in C. lithographica include the muscles of the raptorial appendage and trunk. Conclusions Our results indicate that some ‘typical’ thylacocephalan characters are unique to the group; these autapomorphies contribute to the difficulty of determining thylacocephalan affinities. While the new features reported here are consistent with a eucrustacean affinity, most previous hypotheses for the position of Thylacocephala within Eucrustacea (as Stomatopoda, Thecostraca or Decapoda) are shown to be unlikely. A sister group relationship

  15. A “Rosetta Stone” for metazoan zooplankton: DNA barcode analysis of species diversity of the Sargasso Sea (Northwest Atlantic Ocean)

    NASA Astrophysics Data System (ADS)

    Bucklin, Ann; Ortman, Brian D.; Jennings, Robert M.; Nigro, Lisa M.; Sweetman, Christopher J.; Copley, Nancy J.; Sutton, Tracey; Wiebe, Peter H.

    2010-12-01

    Species diversity of the metazoan holozooplankton assemblage of the Sargasso Sea, Northwest Atlantic Ocean, was examined through coordinated morphological taxonomic identification of species and DNA sequencing of a ˜650 base-pair region of mitochondrial cytochrome oxidase I (mtCOI) as a DNA barcode (i.e., short sequence for species recognition and discrimination). Zooplankton collections were made from the surface to 5,000 meters during April, 2006 on the R/V R.H. Brown. Samples were examined by a ship-board team of morphological taxonomists; DNA barcoding was carried out in both ship-board and land-based DNA sequencing laboratories. DNA barcodes were determined for a total of 297 individuals of 175 holozooplankton species in four phyla, including: Cnidaria (Hydromedusae, 4 species; Siphonophora, 47); Arthropoda (Amphipoda, 10; Copepoda, 34; Decapoda, 9; Euphausiacea, 10; Mysidacea, 1; Ostracoda, 27); and Mollusca (Cephalopoda, 8; Heteropoda, 6; Pteropoda, 15); and Chaetognatha (4). Thirty species of fish (Teleostei) were also barcoded. For all seven zooplankton groups for which sufficient data were available, Kimura-2-Parameter genetic distances were significantly lower between individuals of the same species (mean=0.0114; S.D. 0.0117) than between individuals of different species within the same group (mean=0.3166; S.D. 0.0378). This difference, known as the barcode gap, ensures that mtCOI sequences are reliable characters for species identification for the oceanic holozooplankton assemblage. In addition, DNA barcodes allow recognition of new or undescribed species, reveal cryptic species within known taxa, and inform phylogeographic and population genetic studies of geographic variation. The growing database of "gold standard" DNA barcodes serves as a Rosetta Stone for marine zooplankton, providing the key for decoding species diversity by linking species names, morphology, and DNA sequence variation. In light of the pivotal position of zooplankton in ocean

  16. Comparative brain architecture of the European shore crab Carcinus maenas (Brachyura) and the common hermit crab Pagurus bernhardus (Anomura) with notes on other marine hermit crabs.

    PubMed

    Krieger, Jakob; Sombke, Andy; Seefluth, Florian; Kenning, Matthes; Hansson, Bill S; Harzsch, Steffen

    2012-04-01

    The European shore crab Carcinus maenas and the common hermit crab Pagurus bernhardus are members of the sister taxa Brachyura and Anomura (together forming the taxon Meiura) respectively. Both species share similar coastal marine habitats and thus are confronted with similar environmental conditions. This study sets out to explore variations of general brain architecture of species that live in seemingly similar habitats but belong to different major malacostracan taxa and to understand possible differences of sensory systems and related brain compartments. We examined the brains of Carcinus maenas, Pagurus bernhardus, and three other hermit crab species with immunohistochemistry against tyrosinated tubulin, f-actin, synaptic proteins, RF-amides and allatostatin. Our comparison showed that their optic neuropils within the eyestalks display strong resemblance in gross morphology as well as in detailed organization, suggesting a rather similar potential of processing visual input. Besides the well-developed visual system, the olfactory neuropils are distinct components in the brain of both C. maenas and P. bernhardus as well as the other hermit crabs, suggesting that close integration of olfactory and visual information may be useful in turbid marine environments with low visibility, as is typical for many habitats such as, e.g., the Baltic and the North Sea. Comparing the shape of the olfactory glomeruli in the anomurans showed some variations, ranging from a wedge shape to an elongate morphology. Furthermore, the tritocerebrum and the organization of the second antennae associated with the tritocerebrum seem to differ markedly in C. maenas and P. bernhardus, indicating better mechanosensory abilities in the latter close to those of other Decapoda with long second antennae, such as Astacida, Homarida, or Achelata. This aspect may also represent an adaptation to the "hermit lifestyle" in which competition for shells is a major aspect of their life history. The shore

  17. The implications of a Silurian and other thylacocephalan crustaceans for the functional morphology and systematic affinities of the group.

    PubMed

    Haug, Carolin; Briggs, Derek E G; Mikulic, Donald G; Kluessendorf, Joanne; Haug, Joachim T

    2014-08-22

    Thylacocephala is a group of enigmatic extinct arthropods. Here we provide a full description of the oldest unequivocal thylacocephalan, a new genus and species Thylacares brandonensis, which is present in the Silurian Waukesha fauna from Wisconsin, USA. We also present details of younger, Jurassic specimens, from the Solnhofen lithographic limestones, which are crucial to our interpretation of the systematic position of Thylacocephala. In the past, Thylacocephala has been interpreted as a crustacean ingroup and as closely related to various groups such as cirripeds, decapods or remipeds. The Waukesha thylacocephalan, Thylacares brandonensis n. gen. n. sp., bears compound eyes and raptorial appendages that are relatively small compared to those of other representatives of the group. As in other thylacocephalans the large bivalved shield encloses much of the entire body. The shield lacks a marked optical notch. The eyes, which project just beyond the shield margin, appear to be stalked. Head appendages, which may represent antennulae, antennae and mandibles, appear to be present. The trunk is comprised of up to 22 segments. New details observed on thylacocephalans from the Jurassic Solnhofen lithographic limestones include antennulae and antennae of Mayrocaris bucculata, and endites on the raptorial appendages and an elongate last trunk appendage in Clausocaris lithographica. Preserved features of the internal morphology in C. lithographica include the muscles of the raptorial appendage and trunk. Our results indicate that some 'typical' thylacocephalan characters are unique to the group; these autapomorphies contribute to the difficulty of determining thylacocephalan affinities. While the new features reported here are consistent with a eucrustacean affinity, most previous hypotheses for the position of Thylacocephala within Eucrustacea (as Stomatopoda, Thecostraca or Decapoda) are shown to be unlikely. A sister group relationship to Remipedia appears compatible

  18. [Feeding ecology of Conger myriaster and structure of the food webs in artificial reef zone, Laoshan Bay, China].

    PubMed

    Liu, Hong Yan; Sun, Tong Tong; Zeng, Xiao Qi; Zhang, Pei Dong; Li, Wen Tao; Zhang, Xiu Mei

    2018-04-01

    Based on cage net and longline fishing surveys in Laoshan Bay, China, from April 2015 to January 2017, a total of 279 Conger myriaster stomach samples were analyzed to study their feeding ecology, including diet composition, feeding type, feeding grade, feeding intensity, trophic niche, and trophic level. The stomach content analysis of nine key fish species (including Sebastes schlegelii, Hexagrammos otakii, Hexagrammos agrammus, Sebastiscus mamoratus, Lateolabrax maculatus, etc.), were conducted to examine the food webs in artificial reef zone. The results showed that the diet of C. myriaster consisted of more than 30 species belonging to seven orders, in which shrimps were the most dominant prey species, followed by fishes and cephalopods. The dominant species in the diet of C. myriaster were H.otakii, Enedrias fangi, Trachypenaeus curvirostris, Ammodytes personatus and Alpheus japonicas. The diet composition of C. myriaster varied with season and anal length. Fishes and shrimps were the two important groups throughout the years. Cephalopods were predominant in spring. Cephalopods and crabs were predominant in Autumn. Fish eggs were eaten mostly during winter. Fish eggs and T. curvirostris were the dominant prey groups of the C. myriaster with anal length ≤120 mm, whereas A. personatus and A. japonicas were the dominant prey groups of the C. myriaster with anal length 120-130 mm, H.otakii and E.fangi were the dominant prey of the C. myriaster with anal length >130 mm. The percentage of empty stomach of C. myriaster varied significantly with season, but the mean stomach fullness index did not. The percentage of empty stomach and mean stomach fullness index did not differ significantly among different anal length groups. The trophic levels of the key fish species were higher than level 3, with C. myriaster at the top of food webs (with a trophic level of 4.636). Decapoda, crabs, amphipoda and molluscs were the main prey of key fish species, while Crustaceans

  19. [Spatial and temporal variation in diet composition of invertivore fishes in a tropical stream, Venezuela].

    PubMed

    Ortaz, Mario; Martín, Ricardo; López-Ordaz, Adriana

    2011-09-01

    Invertivores fishes are an important component of neotropical streams and they represent a link between aquatic invertebrates and piscivorous species. This study evaluated the breadth diet and interspecific food overlap of nine invertivores fish species during three consecutive hydrological phases: falling (December/07, January/08, February/08 and March/08), low (April/08) and rising waters (June/08), in two sections of a Venezuelan neotropical stream, which were located at different elevation, high watershed (HW) and low watershed (LW). The fishes were collected with a beach seine (5mm mesh) between 8:00 and 11:00 hours. The diet of each species was evaluated using an index of relative importance (IRI), which includes as variables the number, weight and occurrence frequency of food items consumed. The Levin' index (B ) and Morisita (IM) were used to estimate the breadth diet and interspecific food overlap, respectively. All estimations were made using the numeric proportion of preys. Nine fish species were captured, eight Characiformes, of which three were captured in HW (Knodus deuteronoides, Creagrutus bolivari and C. melasma) and five in LW (Thoracocharax stellatus, Moenkhausia lepidura, Cheirodon pulcher, Ctenobrycon spilurus and Aphyocharax alburnus), and one Cyprinodontiformes (Poecilia reticulata), which was also found in HW. In HW aquatic insects were the main resource consumed by fishes while plant material and terrestrial arthropods were secondary resources. In LW the fishes ingested all of these items in addition to zooplankton (Copepoda, Cladocera and larval stages of Decapoda). However, there was a temporal replacement with a predominance of zooplankton in falling and low water. In general, the breadth diet decreased during the falling water in both sections and increased in rising water. However, the average breadth diet was higher in HW. The interspecific food overlap was high in HW while low values were more frequent in LW and its temporal

  20. Chinese mitten crab surveys of San Joaquin River basin and Suisun Marsh, California, 2000

    USGS Publications Warehouse

    May, Jason T.; Brown, Larry R.

    2001-01-01

    Juvenile Chinese mitten crabs (Eriocheir sinensis) are known to use both brackish and freshwater habitats as rearing areas. The objectives of this study were to examine the habitat use and potential effects of mitten crabs in the freshwater habitats of the San Joaquin River drainage up-stream of the Sacramento-San Joaquin Delta. After several unsuccessful attempts to catch or observe mitten crabs by trapping, electrofishing, and visual observations, the study was redirected to determine the presence of crabs in the San Joaquin River (in the vicinity of Mossdale) and Suisun Marsh. Monthly surveys using baited traps in the San Joaquin River were done from June through November 2000 and in the Suisun Marsh from August through October 2000. No mitten crabs were caught in the San Joaquin River Basin and only one mitten crab was caught in Suisun Marsh. Surveys were conducted at 92 locations in the San Joaquin River Basin by deploying 352 traps for 10,752 hours of trapping effort; in Suisun Marsh, 34 locations were investigated by deploying 150 traps for 3,600 hours of trapping effort. The baited traps captured a variety of organisms, including catfishes (Ictularidae), yellowfin gobies (Acantho-gobius flavimanus), and crayfish (Decapoda). It is unclear whether the failure to capture mitten crabs in the San Joaquin River Basin and Suisun Marsh was due to ineffective trapping methods, or repre-sents a general downward trend in populations of juvenile mitten crabs in these potential rearing areas or a temporary decline related to year-class strength. Available data (since 1998) on the number of mitten crabs entrained at federal and state fish salvage facilities indicate a downward trend in the number of crabs, which may indicate a declining trend in use of the San Joaquin River Basin by juvenile mitten crabs. Continued monitoring for juvenile Chinese mitten crabs in brackish and freshwater portions of the Sacramento-San Joaquin River Basins is needed to better assess the

  1. Clustering behavior of hermit crabs (Decapoda, Anomura) in an intertidal rocky shore at São Sebastião, southeastern Brazil.

    PubMed

    Turra, A; Leite, F P

    2000-02-01

    The clustering behavior and cluster composition of hermit crabs as well as the patterns of shell utilization of clustered and scattered individuals were studied. This study was conducted in the intertidal region of Grande Beach, São Sebastião, southeastern Brazil. Samples were taken both in randomized transects and 1 m2 quadrats during low tide periods. Crabs were counted, measured (shield length), and sexed. Shells were identified and had their adequacy and condition (physical damage and incrustation) recorded. Clusters occurred mainly in air exposed areas and were dominated or composed only by Clibanarius antillensis. Other species like Paguristes tortugae, Pagurus criniticornis, and Calcinus tibicen were also present in these clusters, but in small numbers. Only one monospecific aggregation composed by individuals of P. criniticornis was recorded in tide pools. Almost all crabs were inactive, despite some that were submerged in tide pools. Most of the individuals of C. antillensis were clustered (70.88%). Scattered individuals were larger than clustered ones and occupied mainly shells of Tegula viridula, which seemed to be the most adequate shell to the crabs. Clustered individuals used less incrusted shells than isolated ones. In general, clustering in Grande Beach presented the same patterns of size and sex distribution, and shell utilization than others already studied, with the exception of the smaller cluster size registered in this area.

  2. Local knowledge of traditional fishermen on economically important crabs (Decapoda: Brachyura) in the city of Conde, Bahia State, Northeastern Brazil

    PubMed Central

    2012-01-01

    Background This article records the traditional knowledge of crab gatherers in the city of Conde, in the North Coast Region of Bahia State, Northeastern Brazil. Methods Data on biological and ecological aspects of economically important brachyuran crustaceans have been obtained from semi-structured interviews and in loco observations conducted from September 2007 to December 2009. A total of 57 fishermen of both genders, aged between 10 and 78 years have been interviewed (individually or collectively) in different contexts; interviewees were asked about aspects such as external morphology, life cycle, trophic ecology, and spatial and temporal distribution of the major economically important brachyuran crustaceans in the region. Seven fishing communities were visited: Siribinha, Sítio do Conde, Poças, Ilha das Ostras, Cobó, Buri and Sempre Viva. Data were analyzed by comparing the information provided by participants with those from the specialized academic literature. Results The results show that artisanal fishermen have a wide ranging and well-grounded knowledge on the ecological and biological aspects of crustaceans. Crab gatherers of Conde know about growth and reproductive behavior of the animals they interact with, especially with regard to the three major biological aspects: “molt”, “walking dance” and “spawning”. Conclusion This knowledge constitutes an important source of information that should be considered in studies of management and sustainable use of fishery resources in the North Coast Region of Bahia State. PMID:22449069

  3. Spermatozoal ultrastructure in four genera of Homolidae (crustacea, decapoda): Exemplified by Homologenus sp., Latreillopsis sp., Homolomannia sibogae and Paromolosis boasi

    NASA Astrophysics Data System (ADS)

    Jamieson, B. G. M.; Guinot, D.; Forges, B. Richer De

    1993-10-01

    The spermatozoa of Homologenus sp., Latreillopsis sp., Homolomannia sibogae and Paromolopsis boasi confirm characteristics of a distinctive homolid spermatozoon previously established for Homola sp., Paromola sp. and Paromola petterdi. Homolid features are (1) moderate anteroposterior depression of the acrosome (ratio of length: width 0.4 0.6) as in lyreidine raninids (0.5), depression being greater in dromiids and dynomenids (both 0.3); (2) the capitate form of the perforatorium, shared with dromiids, dynomenids and lyreidine raninids; (3)the autapomorphic spiked-wheel form of the anterior expansion of the perforatorium; (4) horizontal zonation of the acrosome is possibly a unique synapomorphy of homolids with dromiids and dynomenids, and therefore an autapomorphy of the dromioid-homolid assemblage. In dromiids the posterior zone is proportionately the larger, while in homolids the anterior zone is the larger. The anterior zone is complexly subdivided in dynomenids; (5) the autapomorphic presence of numerous radial arranged extension of the acrosomal operculum into the perforatorium; (6) presence of nuclear arms, a symplesiomorphy of all investigated crabs, but small or questionably sometimes absent in Dromiidae; (7) absence of microtubules from the nuclear arms, as in dromiids, raninids, higher heterotremes and thoracotremes; (8) transient presence of a posterior median process of the nucleus. The process is not seen in dromiids but occurs in anomurans and lower heterotremes; (9) apical perforation of the operculum, also seen, apparently symplesiomorphically, in dromiids, raninids, and lower heterotreme families; (10) absence of an acrosome ray zone, probably homoplasic with absence in raninids; (11) location of most of the cytoplasm, including tortuous membranes and degenerating mitochondria, below the acrosome, also seen in Lyreidus; (12) presence, in at least some species, of centrioles, unknown in dromiids and raninids and variable in occurrence in heterotremes.

  4. Feeding ecology of the deep-water blue-red shrimp Aristeus antennatus (Decapoda: Aristeidae) in the Greek Ionian Sea (E. Mediterranean)

    NASA Astrophysics Data System (ADS)

    Kapiris, Kostas; Thessalou-Legaki, Maria

    2011-01-01

    The feeding habits of the deep-sea blue-red shrimp Aristeus antennatus were determined based on the analysis of 1047 stomach contents, sampled in the Greek Ionian Sea (E. Mediterranean). The diet of this economically and biologically important decapod was studied in relation to the season, size class and sex. The diet of A. antennatus consisted of 54 different prey categories, and belonged mainly to smaller crustaceans (e.g. natantian decapods, euphausiids, tanaidaceans), molluscs, polychaetes, chaetognaths and, to a lesser extent, fishes. The above prey categories consisted of 71-82% of the relative abundance and total occurrence for males and 61-81% for females. Females seemed to be better fed than males (stomach fullness, food quality). A. antennatus displayed a highly diversified diet and the different feeding patterns were discussed. Diet composition showed slight seasonal fluctuations. The observed slight differences on A. antennatus diet among the western, central and eastern Mediterranean could be attributed to the more oligotrophic character of the eastern part of the basin. The principal factors driving the changes in the feeding strategy of this decapod among the seasons are the increased energy demands related to sexual requirements and the food availability in the marine environment. The ontogenetic changes in the shrimp's diet were relatively clear. Larger individuals exhibited selecting prey with a good swimming capacity (e.g. fishes), while the smaller individuals consumed prey with low mobility (e.g. copepods, ostracods).

  5. Morphology of the first zoeal stages of five species of the portunid genus Callinectes (Decapoda, Brachyura) hatched at the laboratory.

    PubMed

    Mantelatto, Fernando L; Reigada, Alvaro L D; Gatti, Aline C R; Cuesta, José A

    2014-05-23

    The genus Callinectes Stimpson, 1860 currently consists of 16 species, six of which are reported in Brazilian coast. In the present study, the first zoeal stages of Callinectes bocourti, C. danae, C. exasperatus, C. ornatus and C. sapidus from Brazil were obtained from ovigerous females. The morphological and meristic characters of all these larval stages are described and illustrated. Those of C. bocourti, C. danae and C. sapidus are redescribed and compared with the previous descriptions, and differences are listed. Larval characters of these species were examined for interspecific differences, as well as larval features to distinguish the genus Callinectes within Portunidae. In addition, other portunid genera and species with a known first zoeal stage are compared, with special attention to those species present in the same geographical area. Our findings concord with some previous molecular studies, and we discuss the complexity within the group.

  6. Population structure, sex ratio and growth of the seabob shrimp Xiphopenaeus kroyeri (Decapoda, Penaeidae) from coastal waters of southern Brazil

    PubMed Central

    Grabowski, Raphael Cezar; Simões, Sabrina Morilhas; Castilho, Antonio Leão

    2014-01-01

    Abstract This study evaluated the growth and population structure of Xiphopenaeus kroyeri in Babitonga Bay, southern Brazil. Monthly trawls were conducted from July 2010 through June 2011, using a shrimp boat outfitted with double-rig nets, at depths from 5 to 17 m. Differences from the expected 0.5 sex ratio were determined by applying a Binomial test. A von Bertalanffy growth model was used to estimate the individual growth, and longevity was calculated using its inverted formula. A total of 4,007 individuals were measured, including 1,106 juveniles (sexually immature) and 2,901 adults. Females predominated in the larger size classes. Males and females showed asymptotic lengths of 27.7 mm and 31.4 mm, growth constants of 0.0086 and 0.0070 per day, and longevities of 538 and 661 days, respectively. The predominance of females in larger size classes is the general rule in species of Penaeidae. The paradigm of latitudinal-effect does not appear to apply to seabob shrimp on the southern Brazilian coast, perhaps because of the small proportion of larger individuals, the occurrence of cryptic species, or the intense fishing pressure in this region. The longevity values are within the general range for species of Penaeidae. The higher estimates for longevity in populations at lower latitudes may have occurred because of the growth constants observed at these locations, resulting in overestimation of this parameter. PMID:25561841

  7. Presumed filter-feeding in a deep-sea benthic shrimp (Decapoda, Caridea, Stylodactylidae), with records of the deepest occurrence of carideans.

    PubMed

    Wicksten, Mary; De Grave, Sammy; France, Scott; Kelley, Christopher

    2017-01-01

    Using the remotely operated vehicle Deep Discoverer , we observed a large stylodactylid shrimp resting on a sedimented sea floor at 4826 m in the Marianas Trench Marine National Monument. The shrimp was not collected but most closely resembled Bathystylodactylus bathyalis , known previously only from a single broken specimen. Video footage shows the shrimp facing into the current and extending its upraised and fringed first and second pereopods, presumably capturing passing particles. The video footage is the first ever to show a living deep-sea stylodactylid and constitutes the deepest record for the family. We provide a list of the deepest reports of caridean shrimps world-wide.

  8. Seismic air gun exposure during early-stage embryonic development does not negatively affect spiny lobster Jasus edwardsii larvae (Decapoda:Palinuridae)

    PubMed Central

    Day, Ryan D.; McCauley, Robert D.; Fitzgibbon, Quinn P.; Semmens, Jayson M.

    2016-01-01

    Marine seismic surveys are used to explore for sub-seafloor oil and gas deposits. These surveys are conducted using air guns, which release compressed air to create intense sound impulses, which are repeated around every 8–12 seconds and can travel large distances in the water column. Considering the ubiquitous worldwide distribution of seismic surveys, the potential impact of exposure on marine invertebrates is poorly understood. In this study, egg-bearing female spiny lobsters (Jasus edwardsii) were exposed to signals from three air gun configurations, all of which exceeded sound exposure levels (SEL) of 185 dB re 1 μPa2·s. Lobsters were maintained until their eggs hatched and the larvae were then counted for fecundity, assessed for abnormal morphology using measurements of larval length and width, tested for larval competency using an established activity test and measured for energy content. Overall there were no differences in the quantity or quality of hatched larvae, indicating that the condition and development of spiny lobster embryos were not adversely affected by air gun exposure. These results suggest that embryonic spiny lobster are resilient to air gun signals and highlight the caution necessary in extrapolating results from the laboratory to real world scenarios or across life history stages. PMID:26947006

  9. Morphological and molecular features of some freshwater prawn species under genus Macrobrachium Spence Bate, 1868 (Crustacea: Decapoda: Palaemonidae) from Myanmar.

    PubMed

    Mar, Win; Kang, Peng-Fei; Mao, Bin; Wang, Yu-Feng

    2018-02-28

    Myanmar is abundant in lakes and rivers, yet only a few investigations on the fauna of shrimps and prawns have been conducted and no molecular characteristics of prawn species have been described. This study reveals the morphologically identification of five freshwater prawn species under the genus Macrobrachium, including M. cavernicola, M. australiense, M. johnsoni, M. josephi and Macrobrachium sp.WMY-2017. As there was no previous record and information concerning with M. australiense, M. johnsoni, M. josephi and Macrobrachium sp. WMY-2017, they were regarded as the first record from Myanmar. A fragment of Mitochondrial Cytochrome Oxidase I Gene (COI) was amplified successfully from three studied species: M. australiense, M. josephi, and Macrobrachium sp.WMY-2017. The interspecific divergences of studied species varied from 0.01 to 0.15. The phylogenetic tree based on COI fragment sequences showed that M. australiense was closely related to M. rosenbergii, while Macrobrachium sp. WMY-2017 was closest to M. josephi. The results of molecular phylogeny has clarified the relationship within the genus Macrobrachium and represents the first step toward understanding the pattern of speciation base on molecular approach in Myanmar.

  10. Life history of the vulnerable endemic crayfish Cambarus (Erebicambarus) maculatus Hobbs and Pflieger, 1988 (Decapoda: Astacoidea: Cambaridae) in Missouri, USA

    USGS Publications Warehouse

    DiStefano, Robert J.; Westhoff, Jacob T.; Ames, Catlin W.; Rosenberger, Amanda E.

    2016-01-01

    The vulnerable freckled crayfish, Cambarus maculatus Hobbs and Pflieger, 1988, is endemic to only one drainage in eastern Missouri, USA, which is impacted by heavy metals mining and adjacent to a rapidly-expanding urban area. We studied populations of C. maculatus in two small streams for 25 months to describe annual reproductive cycles, and gather information about fecundity, sex ratio, size at maturity, size-class structure, and growth, capturing a monthly average of more than 50 individuals from each of the two study populations. Information about the density of the species at supplemental sampling streams was also obtained. The species exhibited traits consistent with a K-strategist life history; long-lived, slow-growing, with fewer but larger eggs than sympatric crayfish species. Breeding season occurred in mid- to late autumn, potentially extending into early winter. Egg brooding occurred primarily in May. Young of year were first observed in June. We estimated that these populations contained four to six size-classes, observed smaller individuals grew faster than larger individuals, and most became sexually mature in their second year of life. Densities of C. maculatus were low relative to several sympatric species of Orconectes Cope, 1872. Life history information presented herein will be important for anticipated future conservation efforts.

  11. The trophic position of the alien crab Rhithropanopeus harrisii (crustacea decapoda panopeidae) in the Taman Bay, Sea of Azov community

    NASA Astrophysics Data System (ADS)

    Zalota, A. K.; Kolyuchkina, G. A.; Tiunov, A. V.; Biriukova, S. V.; Spiridonov, V. A.

    2017-03-01

    This work concerns the trophic web positioning of the alien crab Rhithropanopeus harrisii and other common marine invertebrate species and fishes in the benthic ecosystem of the shallows of Taman Bay, Sea of Azov. The base of the trophic web in this system is composed of phytoplankton, macrophytes (algae and marine grasses), and reeds that use atmospheric carbon for photosynthesis. Analysis of the isotopic composition of nitrogen and carbon has shown that although marine grasses are dominating primary producers in the shallows of the bay, primary consumers (such as Cerastoderma glaucum, Porifera gen. sp., Gammarus aequicauda, Deshayesorchestia deshayesii and Idotea balthica) only partially use this organic source; instead, they use a combination of different sources of primary production. It has been shown that the food source of the alien crab is primarily of animal origin. In Taman Bay, R. harrisii is on the same trophic level as other carnivores/scavengers: benthic fishes Syngnathus nigrolineatus, Gobius spp. and native crab Pilumnus hirtellus and shrimp Palaemon adspersus.

  12. [Influence of lunar cycle on catches of spiny lobster Panulirus argus (Decapoda: Palinuridae) in the Gulf of Batabanó, Cuba].

    PubMed

    Lopeztegui, Alexander; Baisre, Julio A; Capetillo, Norberto

    2011-03-01

    Many biological processes such as reproductive and migratory behaviours have been associated with moon cycles. In this study, the nocturnal light levels associated with lunar cycle (INT) were correlated with daily catch rate of lobster P. argus, during seven lunar months of 2002 fishing period, to determine a possible relationship between these variables. The lobster catches were obtained from three fishing companies that develop their activities in the Gulf of Batabanó: EPICOL that fishes in Coloma area; PESCAHABANA in Batabanó area and PESCAISLA in Isla area. Daily catch per boat (CDB) was used as a measurement of daily catch variations (catch rate). The correlation was analyzed showing it in chronological graphs based on average of CDB per lunar phases, comparing lobster catch rate per lunar phases -with the Kruskal-Wallis test-. Spearman rank correlation coefficient and cross correlation techniques were also applied. Similarities between lobster catch rate and the lunar cycle were not found. Spearman rank correlation coefficient was modularly smaller than 0.1 in all cases and demonstrated quantitatively that correlation between CDB and INT does not exist. Kruskal-Wallis test detected differences only in Batabanó area but not when making the analyses for the whole Gulf of Batabanó. Finally, the cross correlations do not detected significance in any zone, as well. It is concluded that, in opposition to what other authors have reported, the catch rates of P. argus and the lunar cycle did not show significant correlation in the Gulf of Batabanó. This trend was independent of the fishing art, which varied according to the time of the year that was analyzed.

  13. Three new species of freshwater crabs of the genus Pseudothelphusa (De Saussure, 1857) (Crustacea: Decapoda: Pseudothelphusidae) from Mexico.

    PubMed

    Ojeda-Escoto, Juan Carlos; Villalobos, José Luis; Álvarez, Fernando

    2017-01-11

    Three new species of freshwater crabs of the genus Pseudothelphusa (De Saussure, 1857) from south-central Mexico are described: Pseudothelphusa acahuizotla n. sp., P. ixtapan n. sp., and P. purhepecha n. sp. The new species are included in Pseudothelphusa due to a male gonopod with torsion and the presence of the characteristic mesial process and caudomarginal projection. Pseudothelphusa acahuizotla n. sp. is morphologically similar to P. belliana Rathbun, 1898, but can be distinguished by the relative size of the distal lobe of the caudomarginal projection and by the presence of a conical tooth on the caudal surface of the mesial process of the male gonopod. Pseudothelphusa ixtapan n. sp. is similar to P. dilatata Rathbun, 1898, and P. morelosis Pretzmann, 1968, and can be distinguished by a mesial process of the male gonopod with only one lateral tooth and an inferior margin with small teeth. Pseudothelphusa puerhepechae n. sp. exhibits a mesial process of the male gonopod with two triangular spines on its lateral margin, a character that with some variations is present in P. nayaritae Álvarez & Villalobos, 1994, P. rechingeri Pretzmann, 1965, P. lophophallus Rodríguez & Smalley, 1969, and P. parabelliana Álvarez 1989; but it can be distinguished by the separation and shape of the two spines of the mesial process and the shape of the lobes of the caudomarginal projection. With the new species described herein there are now 29 species in the genus Pseudothelphusa.

  14. Miocene squat lobsters (Decapoda, Anomura, Galatheoidea) of the Central Paratethys - a review, with description of a new species of Munidopsis.

    PubMed

    Hyžný, M; Gašparič, R; Robins, C M; Schlögl, J

    2014-10-01

    All squat lobsters of the families Galatheidae, Munididae and Munidopsidae from the Miocene of the Central Paratethys are reviewed taxonomically. Based on additional observations emended diagnoses are provided for Agononida cerovensis and Galathea weinfurteri , from the Lower and Middle Miocene, respectively. Munidopsis is represented by two species in the study area; additional data for M. lieskovensis from the Lower Miocene of Slovakia are presented and a new species, M. palmuelleri , from the Middle Miocene of Slovenia is erected. Implications for palaeoenvironmental reconstructions are briefly discussed for each taxon.

  15. Galatheoidea are not monophyletic - molecular and morphological phylogeny of the squat lobsters (Decapoda: Anomura) with recognition of a new superfamily.

    PubMed

    Schnabel, K E; Ahyong, S T; Maas, E W

    2011-02-01

    The monophyletic status of the squat lobster superfamily Galatheoidea has come under increasing doubt by studies using evidence as diverse as larval and adult somatic morphology, sperm ultrastructure, and molecular data. Here we synthesize phylogenetic data from these diverse strands, with the addition of new molecular and morphological data to examine the phylogeny of the squat lobsters and assess the status of the Galatheoidea. A total of 64 species from 16 of the 17 currently recognised anomuran families are included. Results support previous work pointing towards polyphyly in the superfamily Galatheoidea and Paguroidea, specifically, suggesting independent origins of the Galatheidae+Porcellanidae and the Chirostylidae+Kiwaidae. Morphological characters are selected that support clades resolved in the combined analysis and the taxonomic status of Galatheoidea sensu lato is revised. Results indicate that Chirostylidae are more closely related to an assemblage including Aegloidea, Lomisoidea and Paguroidea than to the remaining Galatheoidea and are referred to the superfamily Chirostyloidea to include the Chirostylidae and Kiwaidae. A considerable amount of research highlighting morphological differences supporting this split is discussed. The Galatheoidea sensu stricto is restricted to the families Galatheidae and Porcellanidae, and diagnoses for both Chirostyloidea and Galatheoidea are provided. Present results highlight the need for a detailed revision of a number of taxa, challenge some currently used morphological synapomorphies, and emphasise the need for integrated studies with wide taxon sampling and multiple data sources to resolve complex phylogenetic questions. Copyright © 2010 Elsevier Inc. All rights reserved.

  16. Larval stages of the deep-sea lobster Polycheles typhlops (Decapoda, Polychelida) identified by DNA analysis: morphology, systematic, distribution and ecology

    NASA Astrophysics Data System (ADS)

    Torres, Asvin P.; Palero, Ferran; Dos Santos, Antonina; Abelló, Pere; Blanco, Edurne; Boné, Alexandra; Guerao, Guillermo

    2014-09-01

    A total of 25 specimens of Eryoneicus larvae were collected near the Balearic Archipelago (Western Mediterranean Sea) in 2009 and 2010. Detailed morphological examination indicated that the smallest individual corresponded with the first zoea (ZI) stage of Polycheles typhlops hatched from a berried female by Guerao and Abelló (J Nat Hist 30(8):1179-1184, 1996). Only two species of deep-sea polychelid lobster, namely P. typhlops and Stereomastis sculpta, are known to occur in the Mediterranean. Genetic distance comparisons and phylogenetic analysis of the mitochondrial 16S rDNA and Cox I genes of this early larva together with adults from several Polycheles and Stereomastis species allowed us to assign it to P. typhlops. This is the first wild-caught larval stage of a polychelid lobster being identified using molecular techniques. The remaining specimens were attributed to zoeal stages II-III and decapodid stage based on morphological comparison. The arrangement of spines along the anterior part of the middorsal line (R, 1, 1, 1, 2, C1), characteristic of the former species E. puritanii, discriminates these larvae from other Eryoneicus found in the Mediterranean. The clear presence of epipods on the third maxilliped and pereiopods of the decapodid stage gives further support to the identification of E. puritanii as the larval stages of P. typhlops. Additionally, information on the ecology of these larvae, their abundances during different seasons, as well as their bathymetric distribution is reported.

  17. Local knowledge of traditional fishermen on economically important crabs (Decapoda: Brachyura) in the city of Conde, Bahia State, Northeastern Brazil.

    PubMed

    de Magalhães, Henrique Fernandes; Costa Neto, Eraldo Medeiros; Schiavetti, Alexandre

    2012-07-02

    This article records the traditional knowledge of crab gatherers in the city of Conde, in the North Coast Region of Bahia State, Northeastern Brazil. Data on biological and ecological aspects of economically important brachyuran crustaceans have been obtained from semi-structured interviews and in loco observations conducted from September 2007 to December 2009. A total of 57 fishermen of both genders, aged between 10 and 78 years have been interviewed (individually or collectively) in different contexts; interviewees were asked about aspects such as external morphology, life cycle, trophic ecology, and spatial and temporal distribution of the major economically important brachyuran crustaceans in the region. Seven fishing communities were visited: Siribinha, Sítio do Conde, Poças, Ilha das Ostras, Cobó, Buri and Sempre Viva. Data were analyzed by comparing the information provided by participants with those from the specialized academic literature. The results show that artisanal fishermen have a wide ranging and well-grounded knowledge on the ecological and biological aspects of crustaceans. Crab gatherers of Conde know about growth and reproductive behavior of the animals they interact with, especially with regard to the three major biological aspects: "molt", "walking dance" and "spawning". This knowledge constitutes an important source of information that should be considered in studies of management and sustainable use of fishery resources in the North Coast Region of Bahia State.

  18. Prediction of the neuropeptidomes of members of the Astacidea (Crustacea, Decapoda) using publicly accessible transcriptome shotgun assembly (TSA) sequence data.

    PubMed

    Christie, Andrew E; Chi, Megan

    2015-12-01

    The decapod infraorder Astacidea is comprised of clawed lobsters and freshwater crayfish. Due to their economic importance and their use as models for investigating neurochemical signaling, much work has focused on elucidating their neurochemistry, particularly their peptidergic systems. Interestingly, no astacidean has been the subject of large-scale peptidomic analysis via in silico transcriptome mining, this despite growing transcriptomic resources for members of this taxon. Here, the publicly accessible astacidean transcriptome shotgun assembly data were mined for putative peptide-encoding transcripts; these sequences were used to predict the structures of mature neuropeptides. One hundred seventy-six distinct peptides were predicted for Procambarus clarkii, including isoforms of adipokinetic hormone-corazonin-like peptide (ACP), allatostatin A (AST-A), allatostatin B, allatostatin C (AST-C) bursicon α, bursicon β, CCHamide, crustacean hyperglycemic hormone (CHH)/ion transport peptide (ITP), diuretic hormone 31 (DH31), eclosion hormone (EH), FMRFamide-like peptide, GSEFLamide, intocin, leucokinin, neuroparsin, neuropeptide F, pigment dispersing hormone, pyrokinin, RYamide, short neuropeptide F (sNPF), SIFamide, sulfakinin and tachykinin-related peptide (TRP). Forty-six distinct peptides, including isoforms of AST-A, AST-C, bursicon α, CCHamide, CHH/ITP, DH31, EH, intocin, myosuppressin, neuroparsin, red pigment concentrating hormone, sNPF and TRP, were predicted for Pontastacus leptodactylus, with a bursicon β and a neuroparsin predicted for Cherax quadricarinatus. The identification of ACP is the first from a decapod, while the predictions of CCHamide, EH, GSEFLamide, intocin, neuroparsin and RYamide are firsts for the Astacidea. Collectively, these data greatly expand the catalog of known astacidean neuropeptides and provide a foundation for functional studies of peptidergic signaling in members of this decapod infraorder. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Two new species of the stenopodidean shrimp genus Spongiocaris Bruce & Baba, 1973 (Crustacea: Decapoda: Spongicolidae) from the Indo-West Pacific.

    PubMed

    Komai, Tomoyuki; Grave, Sammy De; Saito, Tomomi

    2016-05-17

    Two new species of the deep-water spongicolid genus Spongiocaris Bruce & Baba, 1973, are described and illustrated from two localities in the Indo-West Pacific. Spongiocaris panglao n. sp. is described on the basis of material from the Bohol Sea, the Philippines, at depths of 220-731 m. Spongiocaris tuerkayi n. sp. is described on the basis of material from Atlantis Bank in the southwestern Indian Ocean at depths of 743-1053 m. Among eight known congeners, both new species appear close to S. semiteres Bruce & Baba, 1973, differing in the rostral length and armature, shape of the carapace, telsonal armature, development of the grooming apparatus of the first pereopod and shape of the third pereopod chela. An identification key to the species currently assigned to Spongiocaris is presented.

  20. A new deep-water species of Alpheopsis Coutière, 1897 from the Indo-West Pacific (Decapoda: Alpheidae).

    PubMed

    Anker, Arthur

    2017-01-30

    Alpheopsis keijii sp. nov. is described on the basis of material collected between 90 and 487 m in Japan, the Philippines, Papua New Guinea and Réunion Island. The new species belongs to the A. trispinosa species group and is morphologically closest to A. trispinosa (Stimpson, 1860), A. garricki Yaldwyn, 1971, A. shearmii (Alcock & Anderson, 1899), and especially A. africana Holthuis, 1952. Field data indicates that A. keijii sp. nov. may be associated with deep-water sponge grounds. A provisional key to the currently known species of the A. trispinosa group is provided.

  1. Extreme mitochondrial variation in the Atlantic gall crab Opecarcinus hypostegus (Decapoda: Cryptochiridae) reveals adaptive genetic divergence over Agaricia coral hosts

    PubMed Central

    van Tienderen, Kaj M.; van der Meij, Sancia E. T.

    2017-01-01

    The effectiveness of migration in marine species exhibiting a pelagic larval stage is determined by various factors, such as ocean currents, pelagic larval stage duration and active habitat selection. Direct measurement of larval movements is difficult and, consequently, factors determining the gene flow patterns remain poorly understood for many species. Patterns of gene flow play a key role in maintaining genetic homogeneity in a species by dampening the effects of local adaptation. Coral-dwelling gall crabs (Cryptochiridae) are obligate symbionts of stony corals (Scleractinia). Preliminary data showed high genetic diversity on the COI gene for 19 Opecarcinus hypostegus specimens collected off Curaçao. In this study, an additional 176 specimens were sequenced and used to characterize the population structure along the leeward side of Curaçao. Extremely high COI genetic variation was observed, with 146 polymorphic sites and 187 unique haplotypes. To determine the cause of this high genetic diversity, various gene flow scenarios (geographical distance along the coast, genetic partitioning over depth, and genetic differentiation by coral host) were examined. Adaptive genetic divergence across Agariciidae host species is suggested to be the main cause for the observed high intra-specific variance, hypothesised as early signs of speciation in O. hypostegus. PMID:28079106

  2. ORDER within the chaos: Insights into phylogenetic relationships within the Anomura (Crustacea: Decapoda) from mitochondrial sequences and gene order rearrangements.

    PubMed

    Hua Tan, Mun; Ming Gan, Han; Peng Lee, Yin; Linton, Stuart; Grandjean, Frederic; Ladvocat Bartholomei-Santos, Marlise; Miller, Adam D; Austin, Christopher M

    2018-05-22

    The infraorder Anomura consists of a morphologically and ecologically heterogeneous group of decapod crustaceans, and has attracted interest from taxonomists for decades attempting to find some order out of the seemingly chaotic diversity within the group. Species-level diversity within the Anomura runs the gamut from the "hairy" spindly-legged yeti crab found in deep-sea hydrothermal vent environments to the largest known terrestrial invertebrate, the robust coconut or robber crab. Owing to a well-developed capacity for parallel evolution, as evidenced by the occurrence of multiple independent carcinization events, Anomura has long tested the patience and skill of both taxonomists attempting to find order, and phylogeneticists trying to establish stable hypotheses of evolutionary inter-relationships. In this study, we performed genome skimming to recover the mitogenome sequences of 12 anomuran species including the world's largest extant invertebrate, the robber crab (Birgus latro), thereby over doubling these resources for this group, together with 8 new brachyuran mitogenomes. Maximum-likelihood (ML) and Bayesian-inferred (BI) phylogenetic reconstructions based on amino acid sequences from mitogenome protein-coding genes provided strong support for the monophyly of the Anomura and Brachyura and their sister relationship, consistent with previous studies. The majority of relationships within families were supported and were largely consistent with current taxonomic classifications, whereas many relationships at higher taxonomic levels were unresolved. Nevertheless, we have strong support for a polyphyletic Paguroidea and recovered a well-supported clade of a subset of paguroids (Diogenidae + Coenobitidae) basal to all other anomurans, though this requires further testing with greater taxonomic sampling. We also introduce a new feature to the MitoPhAST bioinformatics pipeline (https://github.com/mht85/MitoPhAST) that enables the extraction of mitochondrial gene order (MGO) information directly from GenBank files and clusters groups based on common MGOs. Using this tool, we compared MGOs across the Anomura and Brachyura, identifying Anomura as a taxonomic "hot spot" with high variability in MGOs among congeneric species from multiple families while noting the broad association of highly-rearranged MGOs with several anomuran lineages inhabiting extreme niches. We also demonstrate the value of MGOs as a source of novel synapomorphies for independently reinforcing tree-based relationships and for shedding light on relationships among challenging groups such as the Aegloidea and Lomisoidea that were unresolved in phylogenetic reconstructions. Overall, this study contributes a substantial amount of new genetic material for Anomura and attempts to further resolve anomuran evolutionary relationships where possible based on a combination of sequence and MGO information. The new feature in MitoPhAST adds to the relatively limited number of bioinformatics tools available for MGO analyses, which can be utilized widely across animal groups. Copyright © 2018. Published by Elsevier Inc.

  3. A spring-matrix model for pigment translocation in the red ovarian chromatophores of the freshwater shrimp Macrobrachium olfersi (Crustacea, Decapoda).

    PubMed

    Boyle, Robert Tew; McNamara, John Campbell

    2008-04-01

    A model for intracellular transport of pigment granules in the red ovarian chromatophores of the freshwater shrimp Macrobrachium olfersi is proposed on the basis of shifts in the equilibrium of resting forces acting on an elastic pigment matrix. The model describes a pigment-transport mechanism in which mechanochemical protein motors like kinesin and myosin alternately stretch and compress a structurally unified, elastic pigment matrix. Quantifiable properties of the spring-matrix obey Hooke's Law during the rapid phases of pigment aggregation and dispersion. The spring-like response of the pigment mass is estimated from previous kinetic experiments on pigment translocation induced by red pigment concentrating hormone, or by the calcium ionophore A23187. Both translocation effectors trigger an initial phase of rapid pigment aggregation, and their removal or washout after complete aggregation produces a phase of rapid pigment dispersion, followed by slow pigment translocation. The rapid-phase kinetics of pigment transport are in reasonable agreement with Hooke's Law, suggesting that such phases represent the release of kinetic energy, probably produced by the mechanochemical protein motors and stored in the form of matrix deformation during the slow phases of translocation. This semiquantitative model should aid in analyzing intracellular transport systems that incorporate an elastic component.

  4. Changes in the nitric oxide system in the shore crab Hemigrapsus sanguineus (Crustacea, Decapoda) CNS induced by a nociceptive stimulus.

    PubMed

    Dyuizen, Inessa V; Kotsyuba, Elena P; Lamash, Nina E

    2012-08-01

    Using NADPH-diaphorase (NADPH-d) histochemistry, inducible nitric oxide synthase (iNOS)-immunohistochemistry and immunoblotting, we characterized the nitric oxide (NO)-producing neurons in the brain and thoracic ganglion of a shore crab subjected to a nociceptive chemical stimulus. Formalin injection into the cheliped evoked specific nociceptive behavior and neurochemical responses in the brain and thoracic ganglion of experimental animals. Within 5-10 min of injury, the NADPH-d activity increased mainly in the neuropils of the olfactory lobes and the lateral antenna I neuropil on the side of injury. Later, the noxious-induced expression of NADPH-d and iNOS was detected in neurons of the brain, as well as in segmental motoneurons and interneurons of the thoracic ganglion. Western blotting analysis showed that an iNOS antiserum recognized a band at 120 kDa, in agreement with the expected molecular mass of the protein. The increase in nitrergic activity induced by nociceptive stimulation suggests that the NO signaling system may modulate nociceptive behavior in crabs.

  5. Taxonomy of the freshwater crabs of Costa Rica, with a revision of the genus Ptychophallus Smalley, 1964 (Crustacea: Decapoda: Pseudothelphusidae).

    PubMed

    Magalhães, Célio; Wehrtmann, Ingo S; Lara, Luis Rólier; Mantelatto, Fernando L

    2015-01-13

    The taxonomy and geographic distribution of the freshwater crabs of the family Pseudothelphusidae Ortmann, 1893, of Costa Rica, Central America, particularly of the genus Ptychophallus Smalley, 1964, are revised. Historical materials deposited in major collections of several institutions were examined, as well as valuable collections in the Zoological Museum of the University of Costa Rica that include abundant specimens obtained recently (2007-2010) in the southern region of the country. The pseudothelphusids of Costa Rica consists of 15 currently valid species belonging to Achlidon Smalley, 1964 (two species), Allacanthos Smalley, 1964 (two species), Potamocarcinus H. Milne Edwards, 1853 (three species), and Ptychophallus (eight species). Two species seem to be restricted to the Atlantic drainage, while seven are known only from the Pacific drainage; six species occur in both drainages. Ptychophallus comprises 13 valid species; four new synonymies are proposed: P. osaensis Rodríguez, 2001, P. campylus Pretzmann, 1968, P. tumimanus ingae            Pretzmann, 1978, and P. barbillaensis Rodríguez & Hedström, 2001, as junior synonyms of P. paraxantusi (Bott, 1968), P. tristani (Rathbum 1896), P. tumimanus (Rathbun, 1898), and P. uncinatus Campos & Lemaitre, 1999, respectively. Two species, P. colombianus (Rathbun, 1896) and P. exilipes (Rathbun, 1898), are considered species inquerendae. Lectotype designations are made for P. montanus and P. colombianus. Three species of Ptychophallus are known exclusively from Costa Rica, five exclusively from Panama, and five species occur in both countries; one species appears to be exclusive of the Atlantic drainage, whereas five are known only from the Pacific drainage and seven occur in both drainages. The gonopod morphology of all species is redescribed and illustrated, and maps of their geographic distribution are furnished. A key to the species of Pseudothelphusidae from Costa Rica and to all species of Ptychophallus is provided. 

  6. Effect of Temperature on Biochemical Composition, Growth and Reproduction of the Ornamental Red Cherry Shrimp Neocaridina heteropoda heteropoda (Decapoda, Caridea)

    PubMed Central

    Tropea, Carolina; Stumpf, Liane; López Greco, Laura Susana

    2015-01-01

    The effect of water temperature on biochemical composition, growth and reproduction of the ornamental shrimp, Neocaridina heteropoda heteropoda, was investigated to determine the optimum temperature for its culture. The effect of embryo incubation temperature on the subsequent performance of juveniles was also evaluated. Ovigerous females and recently hatched juveniles (JI) were maintained during egg incubation and for a 90-day period, respectively, at three temperatures (24, 28 and 32°C). Incubation period increased with decreasing water temperature, but the number and size of JI were similar among treatments. At day 30 of the 90-day period, body weight and growth increment (GI) at 24°C were lower than those at 28 and 32°C. On subsequent days, GI at 24°C exceeded that at 28 and 32°C, leading to a similar body weight among treatments. These results suggest growth was delayed at 24°C, but only for 30 days after hatching. The lipid concentration tended to be lowest, intermediate and highest at 28, 32 and 24°C, respectively, possibly as a consequence of the metabolic processes involved in growth and ovarian maturation. Protein and glycogen concentrations were similar among treatments. Both the growth trajectory and biochemical composition of shrimps were affected by the temperature experienced during the 90-day growth period independently of the embryo incubation temperature. During the growth period, shrimps reached sexual maturity and mated, with the highest proportion of ovigerous females occurring at 28°C. All the females that matured and mated at 32°C lost their eggs, indicating a potentially stressful effect of high temperature on ovarian maturation. Based on high survival and good growth performance of shrimps at the three temperatures tested over the 90-day period it is concluded that N. heteropoda heteropoda is tolerant to a wide range of water temperatures, with 28°C being the optimum temperature for its culture. PMID:25768918

  7. The State of Phylogenetic Analysis: Narrow Visions and Simple Answers-Examples from the Diptera (flies).

    PubMed

    Borkent, Art

    2018-01-17

    . Until such time as sequences can be shown to produce predictive phylogenies (i.e., using Hennigian logic), independent of morphological analysis, they should be viewed with caution and certainly not as a panacea as they are commonly portrayed.The purported comprehensive analyses of phylogenetic relationships between families of Diptera by Wiegmann et al. (2011) and Lambkin et al. (2013) have serious flaws and cannot be considered as the "Periodic Table" of such relationships as originally heralded.Systematists working on Diptera have a plethora of complex and informative morphological synapomorphies in every life stage, either described or awaiting study. Many lineages have the potential of providing a wealth of evolutionary stories to share with other biologists if we produce stable phylogenies based on weighted synapomorphies and interpreted to elucidate the zoogeographic and bionomic divergence of the group. Some lineages are devoid of convincing synapomorphies and, in spite of our desires, should be recognized as being largely uninterpretable.

  8. Latitudinal patterns in the life-history traits of three isolated Atlantic populations of the deep-water shrimp Plesionika edwardsii (Decapoda, Pandalidae)

    NASA Astrophysics Data System (ADS)

    González, José A.; Pajuelo, José G.; Triay-Portella, Raül; Ruiz-Díaz, Raquel; Delgado, João; Góis, Ana R.; Martins, Albertino

    2016-11-01

    Patterns in the life-history traits of the pandalid shrimp Plesionika edwardsii are studied for the first time in three isolated Atlantic populations (Madeira, Canaries and Cape Verde Islands) to gain an understanding of their latitudinal variations. The maximum carapace size of the populations studied, as well as the maximum weight, showed clear latitudinal patterns. The patterns observed may be a consequence of the temperature experienced by shrimps during development, 1.37 ° C higher in the Canaries and 5.96 ° C higher in the Cape Verde Islands than in Madeira. These temperature differences among populations may have induced phenotypic plasticity because the observed final body size decreased as the temperature increased. A latitudinal north-south pattern was also observed in the maximum size of ovigerous females, with larger sizes found in the Madeira area and lower sizes observed in the Cape Verde Islands. A similar pattern was observed in the brood size and maximum egg size. Females of P. edwardsii produced smaller eggs in the Cape Verde Islands than did those at the higher latitude in Madeira. P. edwardsii was larger at sexual maturity in Madeira than in the Cape Verde Islands. The relative size at sexual maturity is not affected by latitude or environmental factors and is the same in the three areas studied, varying slightly between 0.568 and 0.585. P. edwardsii had a long reproductive season with ovigerous females observed all year round, although latitudinal variations were observed. Seasonally, there were more ovigerous females in spring and summer in Madeira and from winter to summer in the Cape Verde Islands. P. edwardsii showed a latitudinal pattern in size, with asymptotic size and growth rate showing a latitudinal compensation gradient as a result of an increased growth performance in the Madeira population compared to that of the Cape Verde Islands.

  9. Larval development to the first eighth zoeal stages in the deep-sea caridean shrimp Plesionika grandis Doflein, 1902 (Crustacea, Decapoda, Pandalidae).

    PubMed

    Jiang, Guo-Chen; Chan, Tin-Yam; Shih, Tung-Wei

    2017-01-01

    The larvae of the deep-sea pandalid shrimp Plesionika grandis Doflein, 1902 were successfully reared in the laboratory for the first time. The larvae reached the eighth zoeal stage in 36 days, both of which are longest records for the genus. Early larval stages of P. grandis bear the general characters of pandalid shrimps and differ from the other two species of Plesionika with larval morphology known in the number of spines on the anteroventral margin of carapace, number of tubercles on antennule, endopod segmentation in antenna, and third maxilliped setation. Although members in Plesionika are often separated into species groups, members of the same species group do not necessarily have similar early larval morphology. Since the zoea VIII of P. grandis still lacks pleopods and fifth pereiopod, this shrimp likely has at least 12 zoeal stages and a larval development of 120 days.

  10. Isolation By Distance (IBD) signals in the deep-water rose shrimp Parapenaeus longirostris (Lucas, 1846) (Decapoda, Panaeidae) in the Mediterranean Sea.

    PubMed

    Lo Brutto, S; Maggio, T; Arculeo, M

    2013-09-01

    The identification of boundaries of genetic demes is one of the major goals for fishery management, and few Mediterranean commercial species have not been studied from a genetic point of view yet. The deep-water rose shrimp Parapenaeus longirostris (Lucas, 1846) is one of the most important components of commercial landings in Mediterranean, its fishery aspects have received much attention, regrettably without any concern for the genetic architecture of its populations. The population structure in the central and eastern Mediterranean Sea (captures from six Italian and two Greek landings) has been analysed on the basis of surveys carried out with mitochondrial and AFLP markers. Data revealed the presence of a gradual discrepancy along a west-east axis. This species, occurring mainly at a depth of between 100 and 400 m, is not strongly confined in isolated demes, but it demonstrates an 'Isolation By Distance' model, within the Mediterranean Sea, which includes geographical areas with a some degree of isolation. The role of hydrodynamic forces, such as currents, water fronts, is discussed; and a further evidence of the 'Levantine isolation' within Mediterranean basin is shown. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. The emergence of lobsters: phylogenetic relationships, morphological evolution and divergence time comparisons of an ancient group (decapoda: achelata, astacidea, glypheidea, polychelida).

    PubMed

    Bracken-Grissom, Heather D; Ahyong, Shane T; Wilkinson, Richard D; Feldmann, Rodney M; Schweitzer, Carrie E; Breinholt, Jesse W; Bendall, Matthew; Palero, Ferran; Chan, Tin-Yam; Felder, Darryl L; Robles, Rafael; Chu, Ka-Hou; Tsang, Ling-Ming; Kim, Dohyup; Martin, Joel W; Crandall, Keith A

    2014-07-01

    Lobsters are a ubiquitous and economically important group of decapod crustaceans that include the infraorders Polychelida, Glypheidea, Astacidea and Achelata. They include familiar forms such as the spiny, slipper, clawed lobsters and crayfish and unfamiliar forms such as the deep-sea and "living fossil" species. The high degree of morphological diversity among these infraorders has led to a dynamic classification and conflicting hypotheses of evolutionary relationships. In this study, we estimated phylogenetic relationships among the major groups of all lobster families and 94% of the genera using six genes (mitochondrial and nuclear) and 195 morphological characters across 173 species of lobsters for the most comprehensive sampling to date. Lobsters were recovered as a non-monophyletic assemblage in the combined (molecular + morphology) analysis. All families were monophyletic, with the exception of Cambaridae, and 7 of 79 genera were recovered as poly- or paraphyletic. A rich fossil history coupled with dense taxon coverage allowed us to estimate and compare divergence times and origins of major lineages using two drastically different approaches. Age priors were constructed and/or included based on fossil age information or fossil discovery, age, and extant species count data. Results from the two approaches were largely congruent across deep to shallow taxonomic divergences across major lineages. The origin of the first lobster-like decapod (Polychelida) was estimated in the Devonian (∼409-372 Ma) with all infraorders present in the Carboniferous (∼353-318 Ma). Fossil calibration subsampling studies examined the influence of sampling density (number of fossils) and placement (deep, middle, and shallow) on divergence time estimates. Results from our study suggest including at least 1 fossil per 10 operational taxonomic units (OTUs) in divergence dating analyses. [Dating; decapods; divergence; lobsters; molecular; morphology; phylogenetics.]. © The Author(s) 2014. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved.For Permissions, please email: journals.permissions@oup.com.

  12. [Variations of the nutritional condition of lobsters Panulirus argus (Decapoda: Palinuridae) in Eastern region of the Gulf of Batabanó, Cuba].

    PubMed

    Lopeztegui Castillo, Alexander; Capetillo Piñar, Norberto; Betanzos Vega, Abel

    2012-03-01

    Nutritional condition can affect survival and growth rate of crustaceans, and this is mostly affected by habitat conditions. This study describes the space-temporary nutritional changes in this commercially important species. With this aim, the variations in the nutritional condition (K) of lobsters from four zones (1, 2, 4 and 5) in the Gulf of Batabanó, Cuba, were determined. For this, the weight/length ratio (K=Pt/Lt) was calculated using animals captured in 1981 and 2010. The nutritional condition between areas and sexes, and years and sexes, was contrasted by a bifactorial ANOVA, and the overall length and weight of lobsters were compared using a t-Test for independent samples and unifactorial ANOVA. It was found that the nutritional condition was significantly greater in males than in females. In addition, significant variations between zones were detected for both years. Nutritional condition of lobsters from Zone five was the highest for 1981, while it was Zone two for 2010. Lobsters nutritional state showed significant variations between years, being greater in 1981 (2.34 +/- 0.84g/mm) than in 2010 (1.96 +/- 0.49g/mm). The inter-zones variations as well as the inter-annual ones seem to be related to the reported variations of the bottom type and the vegetation cover. Seasonal variations in the abundance and distribution of benthic organisms, that constitute food for lobsters, could also be influencing. The differences between sexes, however, were assumed as a consequence of the methodology used and the sexual dimorphism of the species. Due to other K estimation methods, that do not include morphometric measurements, these differences were not detected. We suggested that the P. argus nutritional condition is a good estimator of the habitat condition. Besides, according to the applied K estimation methodology, it was found that different groups of lobsters that have resemblant nutritional condition, did not necessarily observe similarities in the overall mean length or weight, so they could exist under different habitat conditions.

  13. [Reproductive pattern and mean size of sexual maturity of female lobsters Panulirus gracilis (Decapoda: Palinuridae) in Playa Lagarto, Guanacaste, Costa Rica].

    PubMed

    Naranjo Madrigal, Helven

    2012-12-01

    The lobster P. gracilis is important as a fishery resource and also contributes to food security of fishers in coastal communities in the North Pacific of Costa Rica. Due to the importance of updating knowledge related to the reproductive pattern of this species, we analyzed 357 specimens of female lobsters caught by the fishing methods of "hookah" and lung diving, from November 2007 to October 2008 in Playa Lagarto. Furthermore, we examined the size composition by depth; monthly pattern of reproductive activity (RAI) associated with the relative increase in sea surface temperature, and also the mean size at maturity using Generalized Linear Models. Four physiological states of sexual maturity showed that females with no signs of mating or sexual maturity have a minimum mean size of 62.3mm of cephalothorax length (CL). There are characteristics of functional maturity from very small sizes ranging from 30 to 50mm CL, being the smallest berried female reported for this specie of 35.8mm CL and the highest percentage of mature females between 70 and 80mm CL. Percentages of RAI remained above 50% during the year except October and January. In addition, it observed an increase in the RAI that started from April and continued until August associated with a relative increase in temperature on March, although the correlation was not significant (r2=0.49, p>0.05). It is possible that the low mean size at maturity (70.2mm LC) for P. gracilis in this region is related to the fishing activity. It recommends the establishment of a ban in the region of at least five months (April-August) in order to protect the reproductive seasonality of the species and to promote a recruitment increase in the fishing areas.

  14. Three new species of squat lobsters of the genus Fennerogalathea Baba, 1988 (Decapoda: Galatheidae) from the Pacific Ocean.

    PubMed

    Rodriguez-Flores, Paula C; Machordom, Annie; Macpherson, Enrique

    2017-06-09

    The genus Fennerogalathea Baba, 1988 was known to contain two species: F. chacei Baba, 1988, the type species, from the Philippines, Taiwan and Indonesia and F. chirostyloides Tirmizi & Javed, 1993 from the Bay of Bengal. In the present study, three new species of the genus are described and illustrated: F. chani n. sp. from Papua New Guinea, F. cultrata n. sp. from New Caledonia and Vanuatu and F. ensifera n. sp. from Fiji. The new species are morphologically distinguishable on the basis of the shape and spination of the rostrum and the presence/absence of a small spine on the frontal margin of the carapace. The species also show clear genetic differences (COI and 16S rDNA) among them.

  15. Miocene squat lobsters (Decapoda, Anomura, Galatheoidea) of the Central Paratethys – a review, with description of a new species of Munidopsis

    PubMed Central

    Hyžný, M.; Gašparič, R.; Robins, C.M.; Schlögl, J.

    2015-01-01

    All squat lobsters of the families Galatheidae, Munididae and Munidopsidae from the Miocene of the Central Paratethys are reviewed taxonomically. Based on additional observations emended diagnoses are provided for Agononida cerovensis and Galathea weinfurteri, from the Lower and Middle Miocene, respectively. Munidopsis is represented by two species in the study area; additional data for M. lieskovensis from the Lower Miocene of Slovakia are presented and a new species, M. palmuelleri, from the Middle Miocene of Slovenia is erected. Implications for palaeoenvironmental reconstructions are briefly discussed for each taxon. PMID:26005283

  16. A Kinetic Characterization of the Gill (Na+, K+)-ATPase from the Semi-terrestrial Mangrove Crab Cardisoma guanhumi Latreille, 1825 (Decapoda, Brachyura).

    PubMed

    Farias, Daniel L; Lucena, Malson N; Garçon, Daniela P; Mantelatto, Fernando L; McNamara, John C; Leone, Francisco A

    2017-10-01

    We provide a kinetic characterization of (Na + , K + )-ATPase activity in a posterior gill microsomal fraction from the semi-terrestrial mangrove crab Cardisoma guanhumi. Sucrose density gradient centrifugation reveals two distinct membrane fractions showing considerable (Na + , K + )-ATPase activity, but also containing other microsomal ATPases. The (Na + , K + )-ATPase, notably immuno-localized to the apical region of the epithelial pillar cells, and throughout the pillar cell bodies, has an M r of around 110 kDa and hydrolyzes ATP with V M  = 146.8 ± 6.3 nmol Pi min -1  mg protein -1 and K M  = 0.05 ± 0.003 mmol L -1 obeying Michaelis-Menten kinetics. While stimulation by Na + (V M  = 139.4 ± 6.9 nmol Pi min -1  mg protein -1 , K M  = 4.50 ± 0.22 mmol L -1 ) also follows Michaelis-Menten kinetics, modulation of (Na + , K + )-ATPase activity by MgATP (V M  = 136.8 ± 6.5 nmol Pi min -1 mg protein -1 , K 0.5  = 0.27 ± 0.04 mmol L -1 ), K + (V M  = 140.2 ± 7.0 nmol Pi min -1 mg protein -1 , K 0.5  = 0.17 ± 0.008 mmol L -1 ), and NH 4 + (V M  = 149.1 ± 7.4 nmol Pi min -1 mg protein -1 , K 0.5  = 0.60 ± 0.03 mmol L -1 ) shows cooperative kinetics. Ouabain (K I  = 52.0 ± 2.6 µmol L -1 ) and orthovanadate (K I  = 1.0 ± 0.05 µmol L -1 ) inhibit total ATPase activity by around 75%. At low Mg 2+ concentrations, ATP is an allosteric modulator of the enzyme. This is the first study to provide a kinetic characterization of the gill (Na + , K + )-ATPase in C. guanhumi, and will be useful in better comprehending the biochemical underpinnings of osmoregulatory ability in a semi-terrestrial mangrove crab.

  17. A Breeding Population of the Western Pacific Crab Hemigrapsus sanguineus (Crustacea: Decapoda: Grapsidae) Established on the Atlantic Coast of North America.

    PubMed

    McDermott, J J

    1991-08-01

    The west Pacific grapsid crab Hemigrapsus sanguineus was found in the United States for the first time in 1988. Additional crabs were recovered in 1990 from Townsends Inlet and Cape May Harbor, New Jersey (22 males, 16 females), and four of the females collected from June through September were ovigerous. Thus, H. sanguineus has now established itself in southern New Jersey, the first well-documented case of an exotic brachyuran becoming established along the east coast of the United States.

  18. Redescription of Potamonautes sidneyi (Rathbun, 1904) (Decapoda, Potamonautidae) and description of a new congeneric species from KwaZulu-Natal, South Africa

    PubMed Central

    Peer, Nasreen; Gouws, Gavin; Lazo-Wasem, Eric; Perissinotto, Renzo; Miranda, Nelson A.F.

    2017-01-01

    Abstract A new species of freshwater crab, Potamonautes danielsi sp. n., is described from the southern region of the KwaZulu-Natal Province, South Africa. Potamonautes danielsi most closely resembles Potamonautes sidneyi which is re-described here, but can be distinguished by a suite of key morphological characters including carapace shape and width, slim pereopods, inflated propodi of the chelipeds, and the shape and terminal segment length:subterminal segment length ratio of the 1st gonopod. In a previous study (Gouws et al. 2015), a 9.2–11.8 % divergence was found in the mitochondrial COI and 16S genes of the Potamonautes sidneyi clade, allowing for the delineation of a new species. Despite the clear molecular distinction between the two species, it is difficult to separate them based on individual morphological characters, as there is a great deal of overlap even among key features. The new species is found in slow-moving mountain streams and pools at high altitudes between Umhlanga and Mtamvuna, in KwaZulu-Natal. PMID:28331406

  19. Molt and reproduction enhancement together with hemolymph ecdysteroid elevation under eyestalk ablation in the female fiddler crab, Uca triangularis (Brachyura: Decapoda)

    NASA Astrophysics Data System (ADS)

    Supriya, Nagathinkal T.; Sudha, Kappalli; Krishnakumar, Velayudhannair; Anilkumar, Gopinathan

    2017-05-01

    We present the results of eyestalk extirpation experiments performed on the fiddler crab, Uca triangularis at seasons of molting and reproduction, with a view to have a better understanding of the regulatory mechanisms of these two highly energy-demanding processes. Bilateral eyestalk ablation resulted in precocious acceleration of both molting and reproduction, irrespective of the season at which each experiment was conducted. The rate of accelerated ovarian growth, however, was maximum if the eyestalk ablation was conducted during August-January, the breeding season in the wild, or in February-May (molting-reproductive season), wherein a section of the wild population would be engaged in molting and another section in breeding. The highest degree of precocious molt acceleration, on the other hand, was obtained during June-July when the population was primarily engaged in molting, but with no reproductive activity. The precocious oocyte maturation (due to de-eyestalking) was minimal in June-July. Significantly, the eyestalk ablation also resulted in a dramatic increase in the hemolymph ecdysteroid titer, revealing that a high ecdysteroid titer would have no restraining influence on vitellogenesis. No spawning was, however, observed among de-eyestalked females, even though their final oocyte size surpassed the size of the normal mature oocytes, implying that spawning is not exclusively under the control of eyestalk hormones. A comparative study performed on the vitelline components of the experimentals and the controls revealed that the precociously incorporated yolk under eyestalk ablation was biochemically impoverished. These results indicate that throughout the annual cycle, both the somatic and the reproductive growth of U. triangularis are under the influence of inhibitory principles from the eyestalks. It is also revealing that mere deprival of the inhibitory principles does not culminate into successful vitellogenesis. Arguably, the inhibitory influence from the eyestalks could be a prerequisite for normal healthy maturation of the oocytes and spawning.

  20. Between-Habitat Variation of Benthic Cover, Reef Fish Assemblage and Feeding Pressure on the Benthos at the Only Atoll in South Atlantic: Rocas Atoll, NE Brazil

    PubMed Central

    Longo, G. O.; Morais, R. A.; Martins, C. D. L.; Mendes, T. C.; Aued, A. W.; Cândido, D. V.; de Oliveira, J. C.; Nunes, L. T.; Fontoura, L.; Sissini, M. N.; Teschima, M. M.; Silva, M. B.; Ramlov, F.; Gouvea, L. P.; Ferreira, C. E. L.; Segal, B.; Horta, P. A.; Floeter, S. R.

    2015-01-01

    The Southwestern Atlantic harbors unique and relatively understudied reef systems, including the only atoll in South Atlantic: Rocas atoll. Located 230 km off the NE Brazilian coast, Rocas is formed by coralline red algae and vermetid mollusks, and is potentially one of the most “pristine” areas in Southwestern Atlantic. We provide the first comprehensive and integrative description of the fish and benthic communities inhabiting different shallow reef habitats of Rocas. We studied two contrasting tide pool habitats: open pools, which communicate with the open ocean even during low tides, thus more exposed to wave action; and closed pools, which remain isolated during low tide and are comparatively less exposed. Reef fish assemblages, benthic cover, algal turfs and fish feeding pressure on the benthos remarkably varied between open and closed pools. The planktivore Thalassoma noronhanum was the most abundant fish species in both habitats. In terms of biomass, the lemon shark Negaprion brevirostris and the omnivore Melichtys niger were dominant in open pools, while herbivorous fishes (mainly Acanthurus spp.) prevailed in closed pools. Overall benthic cover was dominated by algal turfs, composed of articulated calcareous algae in open pools and non-calcified algae in closed pools. Feeding pressure was dominated by acanthurids and was 10-fold lower in open pools than in closed pools. Besides different wave exposure conditions, such pattern could also be related to the presence of sharks in open pools, prompting herbivorous fish to feed more in closed pools. This might indirectly affect the structure of reef fish assemblages and benthic communities. The macroalgae Digenea simplex, which is uncommon in closed pools and abundant in the reef flat, was highly preferred in herbivory assays, indicating that herbivory by fishes might be shaping this distribution pattern. The variations in benthic and reef fish communities, and feeding pressure on the benthos between open

  1. Between-Habitat Variation of Benthic Cover, Reef Fish Assemblage and Feeding Pressure on the Benthos at the Only Atoll in South Atlantic: Rocas Atoll, NE Brazil.

    PubMed

    Longo, G O; Morais, R A; Martins, C D L; Mendes, T C; Aued, A W; Cândido, D V; de Oliveira, J C; Nunes, L T; Fontoura, L; Sissini, M N; Teschima, M M; Silva, M B; Ramlov, F; Gouvea, L P; Ferreira, C E L; Segal, B; Horta, P A; Floeter, S R

    2015-01-01

    The Southwestern Atlantic harbors unique and relatively understudied reef systems, including the only atoll in South Atlantic: Rocas atoll. Located 230 km off the NE Brazilian coast, Rocas is formed by coralline red algae and vermetid mollusks, and is potentially one of the most "pristine" areas in Southwestern Atlantic. We provide the first comprehensive and integrative description of the fish and benthic communities inhabiting different shallow reef habitats of Rocas. We studied two contrasting tide pool habitats: open pools, which communicate with the open ocean even during low tides, thus more exposed to wave action; and closed pools, which remain isolated during low tide and are comparatively less exposed. Reef fish assemblages, benthic cover, algal turfs and fish feeding pressure on the benthos remarkably varied between open and closed pools. The planktivore Thalassoma noronhanum was the most abundant fish species in both habitats. In terms of biomass, the lemon shark Negaprion brevirostris and the omnivore Melichtys niger were dominant in open pools, while herbivorous fishes (mainly Acanthurus spp.) prevailed in closed pools. Overall benthic cover was dominated by algal turfs, composed of articulated calcareous algae in open pools and non-calcified algae in closed pools. Feeding pressure was dominated by acanthurids and was 10-fold lower in open pools than in closed pools. Besides different wave exposure conditions, such pattern could also be related to the presence of sharks in open pools, prompting herbivorous fish to feed more in closed pools. This might indirectly affect the structure of reef fish assemblages and benthic communities. The macroalgae Digenea simplex, which is uncommon in closed pools and abundant in the reef flat, was highly preferred in herbivory assays, indicating that herbivory by fishes might be shaping this distribution pattern. The variations in benthic and reef fish communities, and feeding pressure on the benthos between open and

  2. as response to seasonal variability

    PubMed

    Badano, Ernesto I; Labra, Fabio A; Martínez-Pérez, Cecilia G; Vergara, Carlos H

    2016-03-01

    Ecologists have been largely interested in the description and understanding of the power scaling relationships between body size and abundance of organisms. Many studies have focused on estimating the exponents of these functions across taxonomic groups and spatial scales, to draw inferences about the processes underlying this pattern. The exponents of these functions usually approximate -3/4 at geographical scales, but they deviate from this value when smaller spatial extensions are considered. This has led to propose that body size-abundance relationships at small spatial scales may reflect the impact of environmental changes. This study tests this hypothesis by examining body size spectra of benthic shrimps (Decapoda: Caridea) and snails (Gastropoda) in the Tamiahua lagoon, a brackish body water located in the Eastern coast of Mexico. We mea- sured water quality parameters (dissolved oxygen, salinity, pH, water temperature, sediment organic matter and chemical oxygen demand) and sampled benthic macrofauna during three different climatic conditions of the year (cold, dry and rainy season). Given the small size of most individuals in the benthic macrofaunal samples, we used body volume, instead of weight, to estimate their body size. Body size-abundance relationships of both taxonomic groups were described by tabulating data from each season into base-2 logarithmic body size bins. In both taxonomic groups, observed frequencies per body size class in each season were standardized to yield densities (i.e., individuals/m(3)). Nonlinear regression analyses were separately performed for each taxonomic group at each season to assess whether body size spectra followed power scaling functions. Additionally, for each taxonomic group, multiple regression analyses were used to determine whether these relationships varied among seasons. Our results indicated that, while body size-abundance relationships in both taxonomic groups followed power functions, the parameters

  3. The complete mitochondrial genome of the stomatopod crustacean Squilla mantis

    PubMed Central

    Cook, Charles E

    2005-01-01

    Background Animal mitochondrial genomes are physically separate from the much larger nuclear genomes and have proven useful both for phylogenetic studies and for understanding genome evolution. Within the phylum Arthropoda the subphylum Crustacea includes over 50,000 named species with immense variation in body plans and habitats, yet only 23 complete mitochondrial genomes are available from this subphylum. Results I describe here the complete mitochondrial genome of the crustacean Squilla mantis (Crustacea: Malacostraca: Stomatopoda). This 15994-nucleotide genome, the first described from a hoplocarid, contains the standard complement of 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and a non-coding AT-rich region that is found in most other metazoans. The gene order is identical to that considered ancestral for hexapods and crustaceans. The 70% AT base composition is within the range described for other arthropods. A single unusual feature of the genome is a 230 nucleotide non-coding region between a serine transfer RNA and the nad1 gene, which has no apparent function. I also compare gene order, nucleotide composition, and codon usage of the S. mantis genome and eight other malacostracan crustaceans. A translocation of the histidine transfer RNA gene is shared by three taxa in the order Decapoda, infraorder Brachyura; Callinectes sapidus, Portunus trituberculatus and Pseudocarcinus gigas. This translocation may be diagnostic for the Brachyura. For all nine taxa nucleotide composition is biased towards AT-richness, as expected for arthropods, and is within the range reported for other arthropods. Codon usage is biased, and much of this bias is probably due to the skew in nucleotide composition towards AT-richness. Conclusion The mitochondrial genome of Squilla mantis contains one unusual feature, a 230 base pair non-coding region has so far not been described in any other malacostracan. Comparisons with other Malacostraca show that all

  4. A new species of decorator crabs, genus Menaethiops Alcock, 1895 (Crustacea: Decapoda: Brachyura: Majoidea: Epialthidae), from Abu-Musa Island, Persian Gulf, Iran.

    PubMed

    Naderloo, Reza

    2015-03-02

    Menaethiops abumusa n. sp. is closely similar to M. bicornis Alcock, 1985, and M. gadaniensis Kazmi & Tirmizi, 1999, regarding the relatively contiguous rostral spines. The new species is easily distinguishable from its two congeners by having distinctly round angles of orbital eaves and distally divergent rostral spines. Whereas in M. bicornis, and M. gadaniensis, the angles of orbital eaves are anteriorly produced and rostral spines are closely attached to each other along their entire length.  Other morphological differences include the carapace spination/granulation, basal antennal segments, and morphology of the male's first gonopod. Menaethiops gadaniensis was described from Gadani, Pakistan and was only known from the type locality, but is here recorded for the first time from the Gulf of Oman.

  5. Antennular Morphology and Contribution of Aesthetascs in the Detection of Food-related Compounds in the Shrimp Palaemon adspersus Rathke, 1837 (Decapoda: Palaemonidae).

    PubMed

    Solari, Paolo; Sollai, Giorgia; Masala, Carla; Loy, Francesco; Palmas, Francesco; Sabatini, Andrea; Crnjar, Roberto

    2017-04-01

    Shrimp are an essential ecological component of marine ecosystems, and have commercial importance for human consumption and aquaculture. Like other decapod crustaceans, shrimp rely on chemical senses to detect and localize food resources by means of chemosensilla that are located mainly on the cephalothoracic appendages. Using the shrimp Palaemon adspersus, a model organism with omnivorous feeding behavior, we aimed to provide comparative information on the role of aesthetascs, antennular sensilla, and flicking behavior in food detection. To this end, we examined i) the morphology of antennular sensilla by field emission scanning electron microscopy, ii) the shrimp's sensitivity to a number of food-related compounds (amino acids and sugars) by means of whole-animal bioassays, and iii) the contribution of the aesthetasc sensilla to food detection. Our results showed that, aside from the aesthetascs, only three other main morphotypes of setae with chemoreceptive features were present in the antennules, thus accounting for relatively simple sensillar equipment. Nevertheless, we found broad-spectrum sensitivity of the shrimp to a number of amino acids (i.e., isoleucine, leucine, methionine, phenylalanine, glycine, tryptophan, cysteine, and tyrosine) and carbohydrates (trehalose, maltose, cellobiose, and fructose) that was consistent with the omnivorous or scavenging habits of the animal. Although aesthetasc ablation attenuated flicking behavior in a chemical stimulus-independent manner, success in detection and short-range localization of food did not rely on the presence of aesthetasc sensilla. This finding confirms the existence of a non-aesthetasc alternative pathway for feeding, with functional redundancy in simple generalist feeder models such as shrimp.

  6. Fecundity of Uca uruguayensis and Chasmagnathus granulatus (Decapoda, Brachyura) from the "Refugio de Vida Silvestre" Bahía Samborombón, Argentina.

    PubMed

    César, I I; Armendáriz, L C; Becerra, R V

    2007-11-01

    The aim of the present work conducted at the Refugio de Vida Silvestre Bahía Samborombón is to analyse the most relevant aspects of the fecundity of Chasmagnathus granulatus and Uca uruguayensis. Samplings were carried out from March 2001 to February 2003. Ovigerous females of U. uruguayensis (N = 13) and C. granulatus (N = 25) were found during spring and summer, their sizes (CW) varied from 9.1 to 11.7 microm for the former species and from 22.8 to 32.4 mm for the latter. The egg diameter in U. uruguayensis ranged from 245 to 260 microm for embryos in the early stage of development and from 250 to 345 microm for those in mid-developmental stage, while in C. granulatus from 250 to 345 microm and from 260 to 365 microm respectively. Fecundity varied from 1126 to 6745 eggs/brood in U. uruguayensis and 15688-57418 eggs/brood in C. granulatus. For those females with broods in mid-developmental stage, several relationships were made. For U. uruguayensis the best correlation coefficients were obtained for the relationships: female weight vs. egg mass weight and carapace width vs. egg mass weight; for C. granulatus the best association was obtained between female size and the egg number and the egg mass weight.

  7. NEW SPECIES OF PARALOMIS (DECAPODA, ANOMURA, LITHODIDAE) FROM A SUNKEN WHALE CARCASS IN THE SAN CLEMENTE BASIN OF SOUTHERN CALIFORNIA. (U915626)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  8. Checklists of Crustacea Decapoda from the Canary and Cape Verde Islands, with an assessment of Macaronesian and Cape Verde biogeographic marine ecoregions.

    PubMed

    GonzÁlez, JosÉ A

    2018-04-23

    The complete list of Canarian marine decapods (last update by González Quiles 2003, popular book) currently comprises 374 species/subspecies, grouped in 198 genera and 82 families; whereas the Cape Verdean marine decapods (now fully listed for the first time) are represented by 343 species/subspecies with 201 genera and 80 families. Due to changing environmental conditions, in the last decades many subtropical/tropical taxa have reached the coasts of the Canary Islands. Comparing the carcinofaunal composition and their biogeographic components between the Canary and Cape Verde archipelagos would aid in: validating the appropriateness in separating both archipelagos into different ecoregions (Spalding et al. 2007), and understanding faunal movements between areas of benthic habitat. The consistency of both ecoregions is here compared and validated by assembling their decapod crustacean checklists, analysing their taxa composition, gathering their bathymetric data, and comparing their biogeographic patterns. Four main evidences (i.e. different taxa; divergent taxa composition; different composition of biogeographic patterns; different endemicity rates) support that separation, especially in coastal benthic decapods; and these parametres combined would be used as a valuable tool at comparing biotas from oceanic archipelagos. To understand/predict south-north faunal movements in a scenario of regional tropicalization, special attention is paid to species having at the Canaries their southernmost occurrence, and also to tropical African warm-affinity species.

  9. Cherax snowden, a new species of crayfish (Crustacea, Decapoda, Parastacidae) from the Kepala Burung (Vogelkop) Peninsula in Irian Jaya (West Papua), Indonesia

    PubMed Central

    Lukhaup, Christian; Panteleit, Jörn; Schrimpf, Anne

    2015-01-01

    Abstract A new species, Cherax snowden sp. n., from the Oinsok River Drainage, Sawiat District in the central part of the Kepala Burung (Vogelkop) Peninsula, West Papua, Indonesia, is described, figured and compared with the closest related species, Cherax holthuisi Lukhaup & Pekny, 2006. This species is collected and exported for ornamental purposes and its commercial name in the pet trade is “orange tip” or “green orange tip”. Both species may be easily distinguished morphologically or by using sequence divergence, which is substantial, for considering Cherax snowden sp. n. to be a new species. PMID:26448698

  10. Changes during late-stage embryonic development from egg-juvenile to free-living hatchling in Chinese freshwater crab Sinopotamon yangtsekiense (Decapoda, Brachyura, Potamidae)

    NASA Astrophysics Data System (ADS)

    Xue, Junzeng; Liu, Yan; Cumberlidge, Neil; Wu, Huixian

    2013-05-01

    This study expands on recent reports that direct development in the Chinese potamid freshwater crab Sinopotamon yangtsekiense involves the completion of all brachyuran larval stages (nauplius, zoea, and megalopa) inside the egg case during embryonic development. Detailed studies of embryonic development in this species revealed the presence of an additional larval stage (the egg-juvenile) between the megalopa and the free-living hatchling crab. We described and compared the appendages of the head, thorax, and abdomen of the egg-juvenile with those of the hatchling crab in S. yangtsekiense. Significant differences were found between most of the appendages of these two stages with a soft exoskeleton in the egg-juvenile, no joint articulation, a slimmer appearance, and a lack of setae when compared with the newly emerged free-living hatchling crab. These modifications of the appendages are related to the confinement within the egg case of the egg-megalopa and egg-juvenile during direct development, and the need for the free-living hatchling freshwater crab to move, feed, and respire. In marine crabs, the megalopa gives rise to the first crab stage whereas in freshwater crabs the egg-juvenile follows the megalopa and immediately precedes the free-living first crab stage.

  11. A new record of the giant freshwater prawn, Macrobrachium spinipes (Schenkel, 1902) (Crustacea: Decapoda: Palaemonidae) from Taiwan, with notes on its taxonomy.

    PubMed

    Shy, Jhy-Yun; Wowor, Daisy; Ng, Peter K L

    2013-11-04

    The giant freshwater prawn Macrobrachium spinipes (Schenkel, 1902) is recorded from Taiwan for the first time and extends the distribution of the species to north of the Tropic of Cancer. The Taiwanese specimens differ slightly from material from Indonesian Papua in the density of the spination of the adult second pereipods, the relative length of the ridge of the posterior submedian plate of thoracite sternite 4, and the color of the carapace, abdomen and pleural condyles.

  12. Effect of salinity on the metabolism and osmoregulation of selected ontogenetic stages of an Amazon population of Macrobrachium amazonicum shrimp (Decapoda, Palaemonidae).

    PubMed

    Mazzarelli, C C M; Santos, M R; Amorim, R V; Augusto, A

    2015-05-01

    Probably as a function of their wide geographical distribution, the different population of Macrobrachium amazonicum shrimp may present distinct physiological, biochemical, reproductive, behavioral, and ecological patterns. These differences are so accentuated that the existence of allopatric speciation has been suggested, although initial studies indicate that the genetic variability of populations happen at an intraspecific level. Among the biological responses described for M. amazonicum populations, those regarding osmoregulation and metabolism play a key role for being related to the occupation of diverse habitats. To this effect, we investigated osmoregulation through the role of free amino acids in cell volume control and metabolism, through oxygen consumption in larvae (zoeae I, II, V and IX) and/or post-larvae of a M. amazonicum population from Amazon, kept in aquaculture fish hatcheries in the state of São Paulo. The results add information regarding the existence of distinct physiological responses among M. amazonicum populations and suggest that possible adjustments to metabolism and to the use of free amino acids as osmolytes of the regulation of the larvae and post-larvae cell volume depend on the appearance of structures responsible for hemolymph osmoregulation like, for example, the gills. In this respect, we verified that zoeae I do not alter their metabolism due to the exposition to fresh or brackish water, but they reduce intracellular concentration of free amino acids when exposed to fresh water, what may suggest the inexistence or inefficient performance of the structures responsible for volume regulation and hemolymph composition. On the other hand, in zoeae II and V exposed to fresh and brackish water, metabolism alterations were not followed by changes in free amino acids concentration. Thus it is possible, as the structures responsible for osmoregulation and ionic regulation become functional, that the role of free amino acids gets diminished and oxygen consumption elevated, probably due to greater energy expenditure with the active transportation of salts through epithelial membranes. Osmotic challenges also seem to alter throughout development, given that in zoeae II oxygen consumption is elevated on brackish water of 18, but in zoeae V it happens in fresh water. After M. amazonicum metamorphosis, free amino acids begin to play an important role as intracellular osmolytes, because we verified an increase of up to 40% in post-larvae exposed to brackish water of 18. The main free amino acids involved in cell volume regulation of ontogenetic stages evaluated were the non essential ones: glutamic acid, glycine, alanine, arginine, and proline. Interestingly, larvae from estuarine population studied here survived until the zoeae V stage in fresh water, but in some populations far from the sea, zoeae die right after eclosion in fresh water or they do not reach zoeae III stage. In addition, given that in favorable conditions caridean shrimp larvae shorten their development, we may infer that the cultivation environment, in which larvae developed in the present work, was appropriate, because almost all zoeae VIII kept on brackish water underwent metamorphosis directly to post-larvae and did not go through zoeae IX stage.

  13. Feeding ecology of non-native Siberian prawns, Palaemon modestus (Heller, 1862) (Decapoda, Palaemonidae), in the lower Snake River, Washington, U.S.A.

    USGS Publications Warehouse

    Tiffan, Kenneth F.; Hurst, William

    2016-01-01

    We used both stomach content and stable isotope analyses to describe the feeding ecology of Siberian prawns Palaemon modestus (Heller, 1862), a non-native caridean shrimp that is a relatively recent invader of the lower Snake River. Based on identifiable prey in stomachs, the opossum shrimp Neomysis mercedis Holmes, 1896 comprised up to 34-55% (by weight) of diets of juvenile to adult P. modestus, which showed little seasonal variation. Other predominant items/taxa consumed included detritus, amphipods, dipteran larvae, and oligochaetes. Stable isotope analysis supported diet results and also suggested that much of the food consumed by P. modestus that was not identifiable came from benthic sources — predominantly invertebrates of lower trophic levels and detritus. Palaemon modestus consumption of N. mercedis may pose a competitive threat to juvenile salmon and resident fishes which also rely heavily on that prey.

  14. Occurrence of the internal parasite Portunion sp. (Isopoda: Entoniscidae) and its effect on reproduction in intertidal crabs (Decapoda: Grapsidae) from New Zealand.

    PubMed

    Brockerhoff, A M

    2004-12-01

    The parasite fauna of 4 intertidal grapsid crabs from New Zealand was studied between 1998 and 2000. The occurrence of an undescribed entoniscid species, Portunion sp. (Isopoda: Epicaridea), is presented. Portunion sp. was found in Cyclograpsus lavauxi (34.1%, n = 1650), Hemigrapsus crenulatus (19.0%, n = 2300), and Helice crassa (11.6%, n = 825) but was absent from Hemigrapsus sexdentatus (n = 636). Parasitized hosts contained mostly 1 female Portunion sp. but occasionally up to 7 females were found. One to 3 dwarf males typically occurred on each mature female Portunion sp. Most developmental stages of female Portunion sp. were found throughout the year, demonstrating that reproduction and infection occurred continuously. Portunion sp. differentially affected male and female hosts. Prevalence was generally higher in male hosts than in female hosts and increased significantly with host size. Female hosts were castrated, whereas males were not. Portunion sp., therefore, influenced the operational sex ratio in its host species, causing a more male-biased ratio.

  15. Molecular and morphological differentiation between two Miocene-divergent lineages of Amazonian shrimps, with the description of a new species (Decapoda, Palaemonidae, Palaemon)

    PubMed Central

    Carvalho, Fabrício Lopes; Magalhães, Célio; Mantelatto, Fernando Luis

    2014-01-01

    Abstract Palaemon carteri (Gordon, 1935) and Palaemon ivonicus (Holthuis, 1950) are morphologically similar species of South American freshwater shrimps. Past studies have questioned the taxonomic status of both species, which are supposed to have partially sympatric geographic distributions in the Amazon basin. We analyzed a 550 bp fragment of the mitochondrial 16S rRNA gene from these Amazonian Palaemon species as well as from 11 palaemonids as the outgroup. Additionally, we checked diagnostic characters of the genus and family as well as other morphological characters that have been little explored before. Palaemon carteri and Palaemon ivonicus are allocated in two sister lineages, with wide genetic divergence and little morphological differentiation. The divergence time between these lineages was estimated as approximately 10 million years ago. Both molecular and morphological data support the taxonomic validity of both Palaemon carteri and Palaemon ivonicus, refuting the hypothesis of synonymy. In addition, a new species, Palaemon yuna sp. n., closely related to Palaemon ivonicus, is described. Our findings indicate that these species can be differentiated using the projection of the anterolateral margin and anterolateral spine of the first antennular segment, shape of the rostrum, and relative size of the appendix masculina. PMID:25561832

  16. Relative growth and morphological sexual maturity size of the freshwater crab Trichodactylus borellianus (Crustacea, Decapoda, Trichodactylidae) in the Middle Paraná River, Argentina

    PubMed Central

    Williner, Verónica; Torres, María Victoria; Carvalho, Débora Azevedo; König, Natalia

    2014-01-01

    Abstract The relative growth of a number of morphological dimensions of the South American freshwater crab Trichodactylus borellianus (Trichodactylidae) were compared and related to sexual dimorphism. Crabs were collected from ponds in the Middle Paraná River in Argentina. A regression model with segmented relationship was used to test for relative growth between these measurements where breakpoints infer the body size at which crabs reach sexual maturity. In both sexes the carapace width and the length, height, and thickness of the right and left chelae were measured, as well as the male pleopod length and the female abdomen width. All of these measurements were found to show positive allometry with the exception of the male pleopod length and the left chelae, which did not show a breakpoint. In females the breakpoint for the abdomen width inferred a morphological sexual maturity at carapace width 6.9 mm. In males the break point for the pleopod length was at carapace width 6.6 mm, with that for the chelae measurements was between carapace widths 6.4 and 6.9 mm. The relative growth pattern in Trichodactylus borellianus was found to be similar to that recorded for other species of the family Trichodactylidae. PMID:25561835

  17. Inferences on mating and sexual systems of two Pacific Cinetorhynchus shrimps (Decapoda, Rhynchocinetidae) based on sexual dimorphism in body size and cheliped weaponry.

    PubMed

    Bauer, Raymond T; Okuno, Junji; Thiel, Martin

    2014-01-01

    Sexual dimorphism in body size and weaponry was examined in two Cinetorhynchus shrimp species in order to formulate hypotheses on their sexual and mating systems. Collections of Cinetorhynchus sp. A and Cinetorhynchus sp. B were made in March, 2011 on Coconut Island, Hawaii, by hand dipnetting and minnow traps in coral rubble bottom in shallow water. Although there is overlap in male and female size, some males are much larger than females. The major (pereopod 1) chelipeds of males are significantly larger and longer than those of females. In these two Cinetorhynchus species, males and females have third maxillipeds of similar relative size, i.e., those of males are not hypertrophied and probably not used as spear-like weapons as in some other rhynchocinetid (Rhynchocinetes) species. Major chelae of males vary with size, changing from typical female-like chelae tipped with black corneous stout setae to subchelate or prehensile appendages in larger males. Puncture wounds or regenerating major chelipeds were observed in 26.1 % of males examined (N = 38 including both species). We interpret this evidence on sexual dimorphism as an indication of a temporary male mate guarding or "neighborhoods of dominance" mating system, in which larger dominant robustus males defend females and have greater mating success than smaller males. Fecundity of females increased with female size, as in most caridean species (500-800 in Cinetorhynchus sp. A; 300-3800 in Cinetorhynchus sp. B). Based on the sample examined, we conclude that these two species have a gonochoric sexual system (separate sexes) like most but not all other rhynchocinetid species in which the sexual system has been investigated.

  18. Ghost shrimps (Decapoda: Axiidea: Callianassidae) as producers of an Upper Miocene trace fossil association from sublittoral deposits of Lake Pannon (Vienna Basin, Slovakia)

    PubMed Central

    Hyžný, Matúš; Šimo, Vladimír; Starek, Dušan

    2015-01-01

    Numerous trace fossils are described from the Late Miocene sediments of the Bzenec Formation exposed at the Gbely section (the Vienna Basin, Slovakia). During deposition of the sediments the area was part of the large, long-lived brackish to freshwater Lake Pannon. Most of the trace fossils are attributed herein to Egbellichnus jordidegiberti igen et ispec. nov. and are interpreted as burrows produced by decapod crustaceans, specifically by a ghost shrimp of the family Callianassidae. This interpretation is based on two independent lines of evidence: environmental requirements of large bioturbators and the burrow morphology itself. The new ichnotaxon is distinguished from other related ichnotaxa by a combination of typically inclined (roughly at an angle of 45°) cylindrical burrows, absence of lining, and tunnels making loops or bends at approximately right angles. The burrow systems at Gbely document the survival of ghost shrimp long after the closure of all seaways and the origin of Lake Pannon. As today, no ghost shrimp are known from long-lived brackish lakes. Egbellichnus from Gbely is the only, although indirect, record of ghost shrimp from a brackish lake environment reported so far. PMID:26089575

  19. Immunolocalization and expression of Na(+)/K(+) -ATPase in embryos, early larval stages and adults of the freshwater shrimp Palaemonetes argentinus (Decapoda, Caridea, Palaemonidae).

    PubMed

    Ituarte, Romina Belén; Lignot, Jehan-Hervé; Charmantier, Guy; Spivak, Eduardo; Lorin-Nebel, Catherine

    2016-06-01

    The euryhaline shrimp Palaemonetes argentinus exemplifies an evolutionary transition from brackish to freshwater habitats that requires adequate osmoregulatory capacities. Hyperosmoregulation is functional at hatching and it likely begins during the embryonic phase allowing this species to develop entirely in fresh water. Here, we investigated the Na(+)/K(+)-ATPase α-subunit gene (nka-α) expression using quantitative real-time PCR and localized Na(+)/K(+)-ATPase (NKA) in ion-transporting epithelia through immunofluorescence microscopy. We reared shrimps from spawning to juvenile stages at two salinities (1, 15 ‰) and maintained adults for 3 weeks at three salinity treatments (1, 15, 25 ‰). nka-α gene expression was measured in: (1) embryos at an early (SI), intermediate (SII) and late (SIII) stage of embryonic development; (2) newly hatched larvae (Zoea I, ZI); and (3) isolated gill tissue of adults. The nka-α expression was low in SI and SII embryos and reached maximum levels prior to hatching (SIII), which were similar to expression levels detected in the ZI. The nka-α expression in SIII and ZI was highest at 15 ‰, whereas salinity did not affect expression in earlier embryos. In SIII, in ZI and in a later zoeal stage ZIV, NKA was localized in epithelial cells of pleurae, in the inner-side epithelium of branchiostegite and in the antennal glands. Gills appeared in the ZIV but NKA immunolabeling of the cells of the gill shaft occurred in a subsequent developmental larval stage, the decapodid. Extrabranchial organs constitute the main site of osmoregulation in early ontogenetic stages of this freshwater shrimp.

  20. Procambarus (Girardiella) holifieldi, a new species of crayfish (Decapoda: Cambaridae) from Alabama with a revision of the Hagenianus Group in the subgenus Girardiella

    Treesearch

    Guenter A. Schuster; Christopher A. Taylor; Susan B. Adams

    2015-01-01

    Procambarus (Girardiella) holifieldi, new species, is a primary burrowing crayfish from a low-lying field in Perry County, Alabama. It belongs to the Hagenianus Group in the subgenus Girardiella. The new species is morphologically most similar to Procambarus (

  1. The Brachyura (Crustacea: Decapoda) of the Deutschen Tiefsee-Expedition auf dem Dampfer 'Valdivia' 1898-1899: dates of publications and authorship.

    PubMed

    Low, Martyn E Y; Lee, Bee Yan; Ng, Peter K L

    2017-10-30

    The consequences for the nomenclature of the Brachyura as a result of the inadvertent publication of new names in the two editions of the narrative of the Deutschen Tiefsee-Expedition auf dem Dampfer 'Valdivia' 1898-1899 that were published before their formal descriptions by Doflein in the scientific reports to the expedition are discussed. Both editions of the narrative are shown to have been issued in parts (Lieferungen). Accurate dates of publication for the parts of the narrative and for Doflein's work are presented. A list of new taxon names in other groups of animals that may also have been inadvertently made available in the narrative is included.

  2. Preliminary survey of a nemertean crab egg predator, Carcinonemertes, on its host crab, Callinectes arcuatus (Decapoda, Portunidae) from Golfo de Nicoya, Pacific Costa Rica

    PubMed Central

    Okazaki, Robert K.; Wehrtmann, Ingo S.

    2014-01-01

    Abstract The possible presence of egg predators in brood masses of portunid crabs from Pacific Central America has not been studied yet. This survey reports the finding of a nemertean crab egg predator on the portunid crab, Callinectes arcuatus, from the Golfo de Nicoya, Pacific Costa Rica. Nemerteans were found in the egg masses of 26 out of the 74 crabs for a prevalence of 35%. The intensity (mean number of worms/ infected crab) was estimated to be 18 with a variance of 1–123 worms/infected crab. No nemerteans were observed either in the 19 Callinectes arcuatus from Golfo Dulce (southern Pacific coast) and the 10 Portunus asper from Herradura-Jaco (central Pacific coast). This nemertean is a member of the genus Carcinonemertes, which has been reported from the Caribbean coast of Panama. However, the encountered Carcinonemertes sp. is the first published finding and report from Costa Rica and Pacific Central America. PMID:25561848

  3. Complex vertical migration of larvae of the ghost shrimp, Nihonotrypaea harmandi, in inner shelf waters of western Kyushu, Japan

    NASA Astrophysics Data System (ADS)

    Tamaki, Akio; Mandal, Sumit; Agata, Yoshihiro; Aoki, Ikumi; Suzuki, Toshikazu; Kanehara, Hisao; Aoshima, Takashi; Fukuda, Yasushi; Tsukamoto, Hideshi; Yanagi, Tetsuo

    2010-01-01

    The position of meroplanktonic larvae in the water column with depth-dependent current velocities determines horizontal transport trajectories. For those larvae occurring in inner shelf waters, little is known about how combined diel and tidally-synchronized vertical migration patterns shift ontogenetically. The vertical migration of larvae of Nihonotrypaea harmandi (Decapoda: Thalassinidea: Callianassidae) was investigated in mesotidal, inner shelf waters of western Kyushu, Japan in July-August 2006. The larval sampling at seven depth layers down to 60 m was conducted every 3 h for 36 h in a 68.5-m deep area 10 km off a major coastal adult habitat. Within a 61-65-m deep area 5-7.5 km off the adult habitat, water temperature, salinity, chlorophyll a concentration, and photon flux density were measured, and water currents there were characterized from harmonic analysis of current meter data collected in 2008. The water column was stratified, with pycnocline, chlorophyll a concentration maximum, and 2% of photon flux density at 2 m, recorded at around 22-24 m. The stratified residual currents were detected in their north component, directed offshore and onshore in the upper and lower mixed layers, respectively. More than 87% of larvae occurred between 20 m and 60 m, producing a net onshore transport of approximately 1.3 km d -1. At the sunset flooding tide, all zoeal-stage larvae ascended, which could further promote retention (1.4-km potential onshore transport in 3 h). The actual onshore transport of larvae was detected by observing their occurrence pattern in a shallow embayment area with the adult habitat for 24 h in October 1994. However, ontogenetic differences in the vertical migration pattern in inner shelf waters were also apparent, with the maximum mean positions of zoeae deepening with increasing stages. Zoeae I and II performed a reverse diel migration, with their minimum and maximum depths being reached around noon and midnight, respectively. Zoeae IV

  4. A new species of freshwater crab of the genus Oziotelphusa Müller, 1887 (Crustacea: Decapoda: Brachyura: Gecarcinucidae) from Tamil Nadu, southern India.

    PubMed

    Raj, Smrithy; Kumar, Appukuttannair Biju; Ng, Peter K L

    2017-12-10

    A new species of gecarcinucid freshwater crab of the genus Oziotelphusa Müller, 1887, is described from stationary or slow-flowing bodies of water in Keeriparai near Nagercoil, in the state of Tamil Nadu in southern India. Oziotelphusa ravi, new species, is distinguished from its congeners by several distinct characters: the median tooth of the posterior margin of epistome forms a distinct bilobed tip in frontal view, the male pleonal somite 6 is narrowly trapezoidal and slightly wider than long with the lateral margins concave, the terminal segment of the male first gonopod is distinctly bent laterally (along the longitudinal axis) at an angle of about 45°, and the proximal part of the outer margin of the subterminal segment of the male first gonopod has a prominent deep concavity.

  5. Re-examination of the eastern Pacific and Atlantic material of Alpheus malleator Dana, 1852, with the description of Alpheus wonkimi sp. nov. (Crustacea, Decapoda, Alpheidae).

    PubMed

    Anker, Arthur; Pachelle, Paulo P G

    2013-01-01

    The bumpy-clawed snapping shrimp, Alpheus malleator Dana, 1852 (Alpheidae), is revised based on the recently collected and older museum material from the eastern Pacific (Panama, Ecuador), Caribbean (Panama, Puerto Rico, Trinidad & Tobago), Brazil (São Paulo), and West Africa (Cape Verde, Senegal, Guinea, Equatorial Guinea, Congo). The eastern Pacific material is assigned to A. wonkimi sp. nov., based on one morphological difference in the colour and thickness of the uropodal spiniform seta, as well as previously published molecular data. The Caribbean, Brazilian and West African material is considered to represent a single, widespread, morphologically variable, amphi-Atlantic taxon, A. malleator. Alpheus pugilator A. Milne-Edwards, 1878 is retained as ajunior synonym of A. malleator, whereas A. tuberculosus Osorio, 1892, A. malleator var. edentatus Zimmer, 1913 and A. belli Coutière, 1898, the latter two based on juvenile specimens, are tentatively placed in the synonymy of A. malleator. Illustrations, including colour photographs, are provided for A. wonkimi sp. nov. and A. malleator and their morphological variability is discussed and illustrated.

  6. First record of the hermit crab genus Cestopagurus Bouvier, 1897 (Crustacea: Decapoda: Anomura: Paguridae) from the South Pacific Ocean and description of a new species.

    PubMed

    Komai, Tomoyuki; Tsuchida, Shinji; Clark, Malcolm R

    2014-09-14

    A fifth species of the pagurid genus Cestopagurus Bouvier, 1897, is described and illustrated on the basis of a single male specimen collected at a depth of 499 m from Hinepuia submarine volcano in the Kermadec Arc, New Zealand. The new species, C. hinepuia, appears similar to C. puniceus Komai & Takeda, 2005 known from waters off Japan, but the different armature of chelipeds distinguishes the new species. It is the first representative of the genus recorded from the South Pacific Ocean. A key for identification of species of the genus is presented. 

  7. Complete mitochondrial genome of the Asian paddle crab Charybdis japonica (Crustacea: Decapoda: Portunidae): gene rearrangement of the marine brachyurans and phylogenetic considerations of the decapods.

    PubMed

    Liu, Yuan; Cui, Zhaoxia

    2010-06-01

    Given the commercial and ecological importance of the Asian paddle crab, Charybdis japonica, there is a clearly need for genetic and molecular research on this species. Here, we present the complete mitochondrial genome sequence of C. japonica, determined by the long-polymerase chain reaction and primer walking sequencing method. The entire genome is 15,738 bp in length, encoding a standard set of 13 protein-coding genes, two ribosomal RNA genes, and 22 transfer RNA genes, plus the putative control region, which is typical for metazoans. The total A+T content of the genome is 69.2%, lower than the other brachyuran crabs except for Callinectes sapidus. The gene order is identical to the published marine brachyurans and differs from the ancestral pancrustacean order by only the position of the tRNA ( His ) gene. Phylogenetic analyses using the concatenated nucleotide and amino acid sequences of 13 protein-coding genes strongly support the monophyly of Dendrobranchiata and Pleocyemata, which is consistent with the previous taxonomic classification. However, the systematic status of Charybdis within subfamily Thalamitinae of family Portunidae is not supported. C. japonica, as the first species of Charybdis with complete mitochondrial genome available, will provide important information on both genomics and molecular ecology of the group.

  8. Significant fluctuations in ecdysteroid receptor gene (EcR) expression in relation to seasons of molt and reproduction in the grapsid crab, Metopograpsus messor (Brachyura: Decapoda).

    PubMed

    Shyamal, Sharmishtha; Anilkumar, G; Bhaskaran, R; Doss, G P; Durica, D S

    2015-01-15

    Metopograpsus messor, a brachyuran crab inhabiting the estuaries of North Kerala (India), is a prolific breeder releasing approximately 14-16 broods a year. The present paper reports the sequence information on the DNA binding domain (C domain, DBD), linker (D domain) and ligand binding domain (E domain, LBD) of M. messor ecdysteroid receptor (MmEcR) gene, the first grapsid brachyuran crab EcR examined. We have also measured MmEcR transcript levels in the ovary and the hepatopancreas throughout the annual cycle, with special reference to seasons of molt and reproduction. MmEcR expression in both the tissues is found to be at its peak (P<0.05) in late premolt crabs (January/May, molt/reproduction season); the expression levels are lowest (P<0.05) during June/July, when the females would neither molt nor reproduce (season for molt/reproduction repose). Intermediate levels of expression were found during the breeding season (August/December). Interestingly, this pattern of gene expression is in concordance with the fluctuating ecdysteroid levels of the hemolymph and Y organ secretory activity. The significant levels of fluctuation in the ovarian expression of MmEcR strongly suggest the ovary as a potential target for ecdysteroid action. A season-wise comparison of the gene expression reveals that ovarian MmEcR transcript levels are higher in breeding crabs (August/December) than the non-breeding animals (June/July), implicating a possible ecdysteroid role in reproduction in M. messor. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. A new species of the genus Petrolisthes Stimpson (Crustacea, Decapoda, Porcellanidae) from the Central Pacific, with remarks and new records for P. aegyptiacus Werding & Hiller

    PubMed Central

    Hiller, Alexandra; Werding, Bernd

    2016-01-01

    Abstract Petrolisthes paulayi sp. n. is described from specimens collected in French Polynesia. The new species belongs to an assemblage of morphologically similar Indo-West Pacific (IWP) species, here designated as the “mesobranchial-spine group”. All species in the group bear carapace spines, including one or more mesobranchial spines, and transverse, piliferous striations on the dorsal surface of carapace and chelipeds. Petrolisthes paulayi sp. n. is distinguishable from all species in the group by its forwardly produced, trilobate front, and a characteristic combination of carapace spines. We also report on the range extension and live coloration of Petrolisthes aegyptiacus Werding & Hiller, another species of the mesobranchial-spine group, so far considered a Red Sea endemic. Specimens from the Mascaréne Islands confirm that the geographic range of the species extends to the southern Indian Ocean. While specimens morphologically similar to Petrolisthes aegyptiacus, and collected in the Line and Society Islands, suggest a large range extension to the Central Pacific, it is probable that these individuals represent an undescribed species closely related to Petrolisthes aegyptiacus. PMID:27667952

  10. Morphological variation of freshwater crabs Zilchiopsis collastinensis and Trichodactylus borellianus (Decapoda, Trichodactylidae) among localities from the middle Paraná River basin during different hydrological periods

    PubMed Central

    Torres, María Victoria; Collins, Pablo Agustín; Giri, Federico

    2014-01-01

    Abstract Measures of hydrologic connectivity have been used extensively to describe spatial connections in riverine landscapes. Hydrologic fluctuations constitute an important macrofactor that regulates other environmental variables and can explain the distribution and abundance of organisms. We analysed morphological variations among individuals of two freshwater crab species, Zilchiopsis collastinensis and Trichodactylus borellianus, from localities of the middle Paraná River basin during two phases of the local hydrological regime. Specimens were sampled at sites (localities) of Paraná River, Saladillo Stream, Salado River and Coronda River when water levels were falling and rising. The conductivity, pH, temperature and geographical coordinates were recorded at each site. The dorsal cephalothorax of each crab was represented using 16 landmarks for Zilchiopsis collastinensis and 14 landmarks for Trichodactylus borellianus. The Canonical Variate Analyses showed differences in shape (for both species) among the crabs collected from the Paraná and Salado Rivers during the two hydrologic phases. We did not find a general distribution pattern for shape among the crab localities. During falling water, the shapes of Zilchiopsis collastinensis were not related to latitude-longitude gradient (i.e., showing greater overlap in shape), while during rising water the shapes were ordered along a distributional gradient according to geographical location. Contrary, shapes of Trichodactylus borellianus were related to latitude-longitude during falling water and were not related to distributional gradient during rising water. The cephalothorax shape showed, in general, no statistically significant covariations with environmental variables for either species. These results show that each freshwater crab species, from different localities of the middle Paraná River, remain connected; however, these connections change throughout the hydrologic regime of the floodplain system. This study was useful for delineating how the relation among shapes of crabs of localities varies during two phases of the hydrological regime and for estimating the connections and geographical patterns in the floodplain system. PMID:25561836

  11. The identity of the semiterrestrial crab Terrathelphusa kuchingensis (Nobili, 1901) (Crustacea: Decapoda: Brachyura: Gecarcinucidae), with descriptions of four new species from southwestern Sarawak, Borneo, Malaysia.

    PubMed

    Grinang, Jongkar; Ng, Peter K L

    2015-04-10

    Four new species of semiterrestrial gecarcinucid crabs are described from limestone and sandstone habitats in southwestern Sarawak, Malaysia: Terrathelphusa aglaia n. sp., T. cerina n. sp., T. kundong n. sp., and T. mas n. sp. The taxonomy of T. kuchingensis (Nobili, 1901) is discussed, its precise identity ascertained from fresh material, and its actual distribution determined. This increases the number of Terrathelphusa species in Borneo to eight.

  12. Ontogeny of salinity tolerance and hyper-osmoregulation by embryos of the intertidal crabs Hemigrapsus edwardsii and Hemigrapsus crenulatus (Decapoda, Grapsidae): survival of acute hyposaline exposure.

    PubMed

    Taylor, H H; Seneviratna, Deepani

    2005-04-01

    The adults of Hemigrapsus edwardsii and Hemigrapsus crenulatus are euryhaline crabs and strong hyper-osmoregulators. Their embryos are carried externally attached to the abdominal pleopods of female crabs, where they are exposed to temporal and spatial changes in salinity associated with their intertidal and estuarine habitats. Although embryos lack the branchial and excretory organs responsible for adult osmoregulation, post-gastrula embryos were highly tolerant of exposure to hypo-osmotic sea water. Detached eggs (embryos+envelopes), of both species, at all developmental stages between gastrulation and hatching, exhibited 80-100% survival for periods up to 96 h in sea water (osmolality, 1050 mmol kg(-1)) and in dilutions to 50%, 10%, and 1%. Cleavage stages were less tolerant of dilution; H. edwardsii, <50% survived 24 h in 10% sea water; H. crenulatus <50% survived 6 h in 10% sea water. Post-gastrulation stages strongly hyper-osmoregulated but cleavage stages were hyper-osmoconformers (maintaining internal osmolality approximately 150 mmol kg(-1) above external). Osmoregulatory capacity was reduced just prior hatching, particularly in H. crenulatus, although salinity tolerance remained high. Gastrulation therefore marks a critical stage in the ontogeny of osmoregulation and salinity tolerance. Total Na+/K(+)-ATPase activity increased greatly during embryogenesis of H. crenulatus (undetectable in blastulae; gastrulae 0.31+/-0.05 pmol P(i) embryo(-1) min(-1); pre-hatching 16.4+/-1.0 pmol P(i) embryo(-1) min(-1)). Na+/K(+)-ATPase activity increased in embryos exposed to dilute sea water for 24 h implicating regulation of this transporter in a short-term acclimation response.

  13. Modulation by K+ Plus NH4+ of microsomal (Na+, K+)-ATPase activity in selected ontogenetic stages of the diadromous river shrimp Macrobrachium amazonicum (Decapoda, Palaemonidae).

    PubMed

    Leone, Francisco A; Bezerra, Thais M S; Garçon, Daniela P; Lucena, Malson N; Pinto, Marcelo R; Fontes, Carlos F L; McNamara, John C

    2014-01-01

    We investigate the synergistic stimulation by K(+) plus NH4 (+) of (Na(+), K(+))-ATPase activity in microsomal preparations of whole zoea I and decapodid III, and in juvenile and adult river shrimp gills. Modulation of (Na(+), K(+))-ATPase activity is ontogenetic stage-specific, and particularly distinct between juveniles and adults. Although both gill enzymes exhibit two different sites for K(+) and NH4 (+) binding, in the juvenile enzyme, these two sites are equivalent: binding by both ions results in slightly stimulated activity compared to that of a single ionic species. In the adult enzyme, the sites are not equivalent: when one ion occupies its specific binding site, (Na(+), K(+))-ATPase activity is stimulated synergistically by ≈ 50% on binding of the complementary ion. Immunolocalization reveals the enzyme to be distributed predominantly throughout the intralamellar septum in the gill lamellae of juveniles and adults. Western blot analyses demonstrate a single immunoreactive band, suggesting a single (Na(+), K(+))-ATPase α-subunit isoform that is distributed into different density membrane fractions, independently of ontogenetic stage. We propose a model for the modulation by K(+) and NH4 (+) of gill (Na(+), K(+))-ATPase activity. These findings suggest that the gill enzyme may be regulated by NH4 (+) during ontogenetic development in M. amazonicum.

  14. Modulation By K+ Plus NH4 + of Microsomal (Na+, K+)-ATPase Activity in Selected Ontogenetic Stages of the Diadromous River Shrimp Macrobrachium amazonicum (Decapoda, Palaemonidae)

    PubMed Central

    Leone, Francisco A.; Bezerra, Thais M. S.; Garçon, Daniela P.; Lucena, Malson N.; Pinto, Marcelo R.; Fontes, Carlos F. L.; McNamara, John C.

    2014-01-01

    We investigate the synergistic stimulation by K+ plus NH4 + of (Na+, K+)-ATPase activity in microsomal preparations of whole zoea I and decapodid III, and in juvenile and adult river shrimp gills. Modulation of (Na+, K+)-ATPase activity is ontogenetic stage-specific, and particularly distinct between juveniles and adults. Although both gill enzymes exhibit two different sites for K+ and NH4 + binding, in the juvenile enzyme, these two sites are equivalent: binding by both ions results in slightly stimulated activity compared to that of a single ionic species. In the adult enzyme, the sites are not equivalent: when one ion occupies its specific binding site, (Na+, K+)-ATPase activity is stimulated synergistically by ≈50% on binding of the complementary ion. Immunolocalization reveals the enzyme to be distributed predominantly throughout the intralamellar septum in the gill lamellae of juveniles and adults. Western blot analyses demonstrate a single immunoreactive band, suggesting a single (Na+, K+)-ATPase α-subunit isoform that is distributed into different density membrane fractions, independently of ontogenetic stage. We propose a model for the modulation by K+ and NH4 + of gill (Na+, K+)-ATPase activity. These findings suggest that the gill enzyme may be regulated by NH4 + during ontogenetic development in M. amazonicum. PMID:24586919

  15. Two new species of hydrothermal vent crabs of the genus Bythograea from the southern East Pacific Rise and from the Galapagos Rift (Crustacea Decapoda Brachyura Bythograeidae).

    PubMed

    Guinot, Danièle; Hurtado, Luis Alberto

    2003-04-01

    Two new species of Bythograea Williams, B. vrijenhoeki n. sp. and B. galapagensis n. sp., are described based on morphology and mitochondrial DNA comparisons. B. vrijenhoeki was collected on the southern East Pacific Rise, south of the Easter Microplate and B. galapagensis from the Galapagos Rift, from where B. intermedia de Saint Laurent was also described. Our analyses indicate that B. vrijenhoeki is the sister species of B. laubieri Guinot and Segonzac, and B. galapagensis is the sister species of B. thermydron Williams. Bythograea is now composed of six described species, all endemic to hydrothermal vents along the East Pacific Rise and from the Galapagos Rift.

  16. Deep-sea squat lobsters of the genus Paramunida Baba, 1988 (Crustacea: Decapoda: Munididae) from north-western Australia: new records and description of three new species.

    PubMed

    Mccallum, Anna W; Cabezas, Patricia; Andreakis, Nikos

    2016-10-04

    Six species of Paramunida are reported from the continental margin of north-western Australia. Three species are new to science: Paramunida christinae sp. nov., P. ioannis sp. nov., and P. spiniantennata sp. nov. Two species are reported for the first time from Australian waters, P. evexa Macpherson, 1996 and P. tricarinata (Alcock, 1894). These species were confirmed by molecular evidence from the mitochondrial markers ND1 and 16S. We also examine phylogenetic relationships within the genus, and provide an identification key for all known Paramunida species.

  17. Variability in prevalence of Cymatocarpus solearis (Trematoda, Brachycoeliidae) in Caribbean spiny lobsters Panulirus argus (Decapoda: Palinuridae) from Bahía de la Ascensión (Mexico).

    PubMed

    Briones-Fourzán, Patricia; Muñoz de Cote-Hernández, Rubén; Lozano-Álvarez, Enrique

    2016-06-01

    Cymatocarpus solearis, a brachycoeliid trematode that parasitizes sea turtles, uses spiny lobsters Panulirus argus as second intermediate hosts. We examined variability in infection by C. solearis in Bahía de la Ascensión, Mexico, a tropical bay with a highly productive fishery for P. argus that is based on the extensive use of casitas (large artificial shelters), which can harbor multiple juveniles and adults of this gregarious lobster species. We sampled 3956 lobsters from 466 casitas distributed over three bay zones within two closed seasons and one fishing season. In these lobsters (9.5-115.2mm carapace length, CL), the average infection prevalence was 11.7% but the probability of infection increased significantly with size. Prevalence varied with season but was consistently higher in one zone than in the other two zones. Infection with C. solearis was negatively related with clinical infection with Panulirus argus Virus 1 (PaV1). We also sampled 405 lobsters from the commercial catch obtained throughout the bay at the onset of the fishing season. In these relatively larger lobsters (70.3-168.0mm CL), average prevalence of C. solearis was higher (23.5%) but was not affected by lobster size or sex. Encysted metacercariae occurred in both abdominal and cephalothoracic muscles. The effects of C. solearis on phenotypic traits of P. argus that may potentially impact the host population dynamics and fisheries remain to be investigated. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Phylogenetic utility, and variability in structure and content, of complete mitochondrial genomes among genetic lineages of the Hawaiian anchialine shrimp Halocaridina rubra Holthuis 1963 (Atyidae:Decapoda).

    PubMed

    Justice, Joshua L; Weese, David A; Santos, Scott Ross

    2016-07-01

    The Atyidae are caridean shrimp possessing hair-like setae on their claws and are important contributors to ecological services in tropical and temperate fresh and brackish water ecosystems. Complete mitochondrial genomes have only been reported from five of the 449 species in the family, thus limiting understanding of mitochondrial genome evolution and the phylogenetic utility of complete mitochondrial sequences in the Atyidae. Here, comparative analyses of complete mitochondrial genomes from eight genetic lineages of Halocaridina rubra, an atyid endemic to the anchialine ecosystem of the Hawaiian Archipelago, are presented. Although gene number, order, and orientation were syntenic among genomes, three regions were identified and further quantified where conservation was substantially lower: (1) high length and sequence variability in the tRNA-Lys and tRNA-Asp intergenic region; (2) a 317-bp insertion between the NAD6 and CytB genes confined to a single lineage and representing a partial duplication of CytB; and (3) the putative control region. Phylogenetic analyses utilizing complete mitochondrial sequences provided new insights into relationships among the H. rubra genetic lineages, with the topology of one clade correlating to the geologic sequence of the islands. However, deeper nodes in the phylogeny lacked bootstrap support. Overall, our results from H. rubra suggest intra-specific mitochondrial genomic diversity could be underestimated across the Metazoa since the vast majority of complete genomes are from just a single individual of a species.

  19. Portunoid crabs as indicators of the Red Sea fauna history and endemism

    NASA Astrophysics Data System (ADS)

    Spiridonov, Vassily; Türkay, Michael; Brösing, Andreas; Al-Aidaroos, Ali

    2013-04-01

    Peculiar environmental conditions and "turbulent" geological history make the Red Sea a laboratory of evolution and a significant area for understanding adaptation processes. To interpret the results of this basin-scale evolutionary experiment revised inventories of taxonomic diversity of particular groups of marine biota are essential. As one of the first results of the Red Sea Biodiversity Survey (RSBS) in the years 2011 - 2012 along the coast of Saudi Arabia (http://www.redseabiodiversity.org/) and examination of earlier collections and literature a revised species list is provided for the portunoid (swimming) crabs (Crustacea Decapoda Portunoidea). This superfamily is one of the most species rich and has one of the broadest habitat scopes among Brachyura in the global scale. The present assessment results in 54 shallow water species (including 2 recorded for the first time in the Red Sea during RSBS), 2 deep water species and 1 semipelagic species Charybdis smithii. Doubtful literature records of another 7 shallow water species remain unconfirmed. Among reliably recorded shallow water species 58 % belong to widespread Indo-West-Pacific (IWP) species, 13% are the species restricted to the western Indian Ocean, 11 % are endemics of the Arabian region (occurring also either in the western Gulf of Aden or along the eastern coast of the Arabian Peninsula, or in both areas) which are usually vicariant to the widespread IWP species, 11% are taxa that are similar to the species occurring elsewhere in the IWP but have morphological peculiarities and probably deserve a specific or subspecific status. Finally 4% of species (Thalamita murinae and Liocarcinus subcorrugatus) appear to be endemic for the Red Sea and show remarkable disjunctions from most closely related species. Carcinus sp. (probably C. aestuarii) is an introduced (but not established) species in the northern Red Sea. The deep water fauna of the Red Sea is unique because it lives in the warm (20.5-21.5 ° C

  20. A micro X-ray computed tomography dataset of South African hermit crabs (Crustacea: Decapoda: Anomura: Paguroidea) containing scans of two rare specimens and three recently described species.

    PubMed

    Landschoff, Jannes; Du Plessis, Anton; Griffiths, Charles L

    2018-04-01

    Along with the conventional deposition of physical types at natural history museums, the deposition of 3-dimensional (3D) image data has been proposed for rare and valuable museum specimens, such as irreplaceable type material. Micro computed tomography (μCT) scan data of 5 hermit crab species from South Africa, including rare specimens and type material, depicted main identification characteristics of calcified body parts. However, low-image contrasts, especially in larger (>50 mm total length) specimens, did not allow sufficient 3D reconstructions of weakly calcified and fine characteristics, such as soft tissue of the pleon, mouthparts, gills, and setation. Reconstructions of soft tissue were sometimes possible, depending on individual sample and scanning characteristics. The raw data of seven scans are publicly available for download from the GigaDB repository. Calcified body parts visualized from μCT data can aid taxonomic validation and provide additional, virtual deposition of rare specimens. The use of a nondestructive, nonstaining μCT approach for taxonomy, reconstructions of soft tissue structures, microscopic spines, and setae depend on species characteristics. Constrained to these limitations, the presented dataset can be used for future morphological studies. However, our virtual specimens will be most valuable to taxonomists who can download a digital avatar for 3D examination. Simultaneously, in the event of physical damage to or loss of the original physical specimen, this dataset serves as a vital insurance policy.

  1. Characteristics and fate of the spermatozoa of Inachus phalangium (Decapoda, Majidae): description of novel sperm structures and evidence for an additional mechanism of sperm competition in Brachyura.

    PubMed

    Rorandelli, Rocco; Paoli, Francesco; Cannicci, Stefano; Mercati, David; Giusti, Fabiola

    2008-03-01

    Various aspects of the reproductive anatomy of the spider crab Inachus phalangium are investigated utilizing light and electron microscopy. Spermatozoal ultrastructure reveals the presence of a glycocalyx in the peripheral region of the periopercular rim, never recorded before in crustacean sperm cells. Sperm cell morphological traits such as semi-lunar acrosome shape, centrally perforate and flat operculum, and absence of a thickened ring, are shared only with Macropodia longirostris, confirming a close phylogenetic relationship of these species and their separation from the other members of the family Majidae. Spermatozoa are transferred to females inside spermatophores of different sizes, but during ejaculate transfer, larger spermatophores might be ruptured by tooth-like structures present on the ejaculatory canal of the male first gonopod, releasing free sperm cells. Such a mechanism could represent the first evidence of a second form of sperm competition in conflict with sperm displacement, the only mechanism of sperm competition known among Brachyura, enabling paternity for both dominant and smaller, non-dominant, males. In addition, we propose several hypotheses concerning the remote and proximal causes of the existence of large seminal receptacles in females of I. phalangium. Among these, genetically diverse progeny, reduction of sexual harassment and phylogenetic retention seem the most plausible, while acquisition of nutrients from seminal fluids, demonstrated in other arthropods, and suggested by previous studies, could be discarded on the basis of the presented data.

  2. A new species of fiddler crab from the Ogasawara (Bonin) Islands, Japan, separated from the widely-distributed sister species Uca (Paraleptuca) crassipes (White, 1847) (Crustacea: Decapoda: Brachyura: Ocypodidae).

    PubMed

    Shih, Hsi-Te; Komai, Tomoyuki; Liu, Min-Yun

    2013-12-10

    A new species of fiddler crab (Brachyura: Ocypodidae), Uca boninensis sp. nov., is described from the Ogasawara (Bonin) Islands, Japan. The new species has previously been identified with the widely distributed U. crassipes (White, 1847), from which it differs by having a slightly differently shaped carapace, and relatively stouter male first gonopods (G1). The recognition of the new species is also supported by differences in the mitochondrial cytochrome oxidase I (COI) and control region (CR) genes. U. boninensis sp. nov., appears to be endemic to the Ogasawara Islands, and as the only known population is small, urgent conservation measures are needed for its protection. Our study brings the total number of the Japanese fiddler crab species to 12.

  3. Hydroacoustical evidence of the expansion of pelagic swarms of Munida gregaria (Decapoda, Munididae) in the Beagle Channel and the Argentine Patagonian Shelf, and its relationship with habitat features

    NASA Astrophysics Data System (ADS)

    Diez, Mariano J.; Cabreira, Ariel G.; Madirolas, Adrián; Lovrich, Gustavo A.

    2016-08-01

    Squat lobsters are highly diversified and widespread decapods, of which only three species form pelagic swarms. Here we infer the expansion of Munida gregaria populations in the Beagle Channel and the Argentine Patagonian Shelf by means of acoustic surveys of pelagic swarms. We also describe the habitat characteristics in which these swarms occur. Acoustic data was collected during three multidisciplinary scientific cruises on board of the R/V Puerto Deseado during 2009, 2012 and 2014. Despite differences in the environmental conditions between the two surveyed areas, between 2009 and 2014 pelagic swarms increased their occurrence and abundance both in the Beagle Channel and on the Argentine Patagonian Shelf. Towards the end of the studied period, pelagic swarms of M. gregaria occurred in new locations, supporting the notion of a population expansion. Within the Beagle Channel swarm expansions were more marked than on the Patagonian Shelf. We here postulate that M. gregaria expansions occur in association with productive areas of the Argentine continental shelf, such as frontal zones, favoured by the squat lobster phenotypic plasticity that permit to exploit resources in both the neritic and benthic environments. At a regional scale on the Patagonian Shelf, three main groups of pelagic swarms of M. gregaria were clearly associated to respective frontal zones. The information presented here is necessary to understand fluctuations in both distribution and abundance patterns of a key species on the Argentine continental shelf. These fluctuations could be direct or indirect indicators of changes in the ecosystem.

  4. Odontonia plurellicola sp. n. and Odontonia bagginsi sp. n., two new ascidian-associated shrimp from Ternate and Tidore, Indonesia, with a phylogenetic reconstruction of the genus (Crustacea, Decapoda, Palaemonidae)

    PubMed Central

    de Gier, Werner; Fransen, Charles H.J.M.

    2018-01-01

    Abstract Two new species of palaemonid shrimp associated with ascidian hosts, Odontonia bagginsi sp. n. from Tidore and Odontonia plurellicola sp. n., from Ternate, Indonesia are described and figured. Through phylogenetic analyses based on both morphological and molecular datasets (mitochondrial Cytochrome c oxidase subunit I gene and the 16S mitochondrial ribosomal gene) of the genus Odontonia, the phylogenetic positions of the new species have been reconstructed. Scanning Electron Microscopy has been used to observe additional characters on dactyli of the ambulatory pereiopods. Odontonia plurellicola sp. n. appears to be more closely related to O. simplicipes and O. seychellensis, but it differs most notably in the morphology of the rostrum and mouthparts. Odontonia plurellicola sp. n. appears to be the only Odontonia species living inside a phlebobranch ascidian Plurella sp. Odontonia bagginsi sp. n. is closely related to O. sibogae, but differs markedly in the abundance of setae on the propodi of the ambulatory pereiopods. In the present paper, O. maldivensis Fransen, 2006 is regarded as a junior synonym of O. rufopunctata Fransen, 2002 based on both morphological and molecular aspects. PMID:29910665

  5. Nectonema zealandica n. sp. (Nematomorpha: Nectonematoidea) parasitising the purple rock crab Hemigrapsus edwardsi (Brachyura: Decapoda) in New Zealand, with notes on the prevalence of infection and host defence reactions.

    PubMed

    Poinar, G; Brockerhoff, A M

    2001-10-01

    A new species of marine hairworm, Nectonema zealandica (Nematomorpha: Nectonematoidea), is described from the purple rock crab Hemigrapsus edwardsi Hilgendorf from the South Island, New Zealand. This is the first record of Nectonema in the South Pacific Ocean and the southernmost locality for the genus. The description is based on juveniles and pre-adults taken from crabs. The new species is characterised by its stomal structure, presence of four cephalic papillae, mesenchyme arranged in eight lobes in pre-adults, insertion of muscle layer increasing body diameter at the septum and translucent anterior chamber. Data on the prevalence of infection over a three-year period, rates of parasitism in relation to host sex and size, and host defence reactions are presented. A list of all reported hosts of nectonematids is included.

  6. Global analysis of the ovarian microRNA transcriptome: implication for miR-2 and miR-133 regulation of oocyte meiosis in the Chinese mitten crab, Eriocheir sinensis (Crustacea:Decapoda).

    PubMed

    Song, Ya-Nan; Shi, Li-Li; Liu, Zhi-Qiang; Qiu, Gao-Feng

    2014-07-01

    MicroRNAs (miRNAs) are small non-coding RNA molecules that downregulate gene expression by base pairing to the 3'-untranslated region (UTR) of target messenger RNAs (mRNAs). Up to now, rare information for the miRNAs is available in decapod crustaceans. Our previous studies showed that many miRNA-binding sites are present in the 3'-UTR of the cyclin B in the Chinese mitten crab Eriocheir sinensis, suggesting that the translation or post-transcription of the crab cyclin B might be regulated by miRNAs during meiosis of oocyte. To identify ovarian miRNAs in the mitten crab, ovarian small RNAs were subjected to high-throughput sequencing using an Illumina Genome Analyzer. Of 14,631,328 reads, 55 known miRNAs representing 44 miRNA families were identified and 136 novel miRNA candidates were predicted. The 5' seed sequences of four miRNAs, miR-2, miR-7, miR-79 and miR-133, were revealed to complementary to miRNA binding sites in 3'-UTR of the cyclin B. Quantitative real time PCR analysis showed that miR-2 and miR-133 are much more abundant in the first metaphase (MI) of meiosis than in germinal vesicle (GV) stage. But their increasing expressions are independent of induction of gonadotropin-releasing hormone (GnRH). Further expression analysis using double-luciferase reporter genes assay showed that miR-2 and miR-133 can downregulate the 3'-UTRs of the crab cyclin B gene, indicating that they could inhibit the translation of the cyclin B. Western blot analysis confirmed that cyclin B protein is completely disappeared in fertilized egg at the metaphase-anaphase transition of meiosis I, suggesting that miR-2 and miR-133 could function in destruction of cyclin B near the end of MI. A high number of miRNAs have been identified from the crab ovarian small RNA transcriptom for the first time. miR-2 and miR-133 exhibit differential expression during the meiotic maturation of the oocytes and have activity in regulating the 3'-UTR of the crab cyclin B gene. This result is inconsistent with recent finding that miRNA activity is globally suppressed in mouse oocytes.

  7. Profilicollis novaezelandensis n. sp. (Polymorphidae) and two other acanthocephalan parasites from shore birds (Haematopodidae and Scolopacidae) in New Zealand, with records of two species in intertidal crabs (Decapoda: Grapsidae and Ocypodidae).

    PubMed

    Brockerhoff, A M; Smales, L R

    2002-05-01

    Profilicollis novaezelandensis n. sp. (Acanthocephala: Polymorphidae) is described from the South Island pied oystercatcher Haematopus ostralegus finschi Martens (Haematopodidae) and the intertidal crab Hemigrapsus crenulatus (Milne Edwards) (Brachyura: Grapsidae) from the South Island of New Zealand. The new species can be distinguished from all the other species of the genus by a combination of the following characters: long neck (13% of total body length for adults) and a subspherical proboscis with 14-16 longitudinal rows of 7-8 hooks. The mud crabs Helice crassa Dana (Grapsidae) and Macrophthalmus hirtipes (Heller) (Ocypodidae) were also harbouring cystacanths and the bar-tailed godwit Limosa lapponica (Linnaeus) (Scolopacidae) juveniles of P. novaezelandensis. This is the first record of brachyuran decapods as intermediate hosts of Acanthocephala from New Zealand. P. antarcticus is recorded from three crab species (Helice crassa, Hemigraspus crenulatus and Macrophthalmus hirtipes) and two bird species (Haematopus o. finschi and Limosa lapponica) in New Zealand. An unidentified species of Plagiorhynchus was also found in two bird species (H. o. finschi and H. unicolor Forster). P. antarcticus and P. novaezelandensis are the first records of Profilicollis from New Zealand.

  8. Photophore counts in the deep-sea commercial shrimp Aristeus alcocki Ramadan, 1938 (Crustacea: Decapoda: Aristeidae), with a revised key to the Indo-West Pacific species of the genus.

    PubMed

    Chan, Tin-Yam; Kumar, Appukuttannair Biju; Yang, Chien-Hui

    2017-10-06

    The availability of abundant fresh material of Aristeus alcocki Ramadan, 1938 from India allowed the evaluation of the variation in the numbers of photophores on the pereiopods in this species, as well as other diagnostic characters for species discrimination. Although the pereiopodal photophore counts in A. alcocki largely overlap with those of A. semidentatus Bate, 1888, it is found that A. alcocki is unique in the Indo-West Pacific species of the genus by the lower end of the cervical carina considerably farther away from the branchiostegal carina. Molecular genetic analysis confirmed the distinct taxonomic status of the six currently known species in this genus from the Indo-West Pacific and a revised key is provided for distinguishing them.

  9. Parasites (Isopoda: Epicaridea and Nematoda) from ghost and mud shrimp (Decapoda: Axiidea and Gebiidea) with descriptions of a new genus and a new species of bopyrid isopod and clarification of Pseudione Kossmann, 1881.

    PubMed

    Boyko, Christopher B; Williams, Jason D; Shields, Jeffrey D

    2017-12-18

    Ghost and mud shrimps in Axiidea and Gebiidea are hosts to parasitic epicaridean isopods, including species in Bopyridae and Ionidae. These isopods can reach high prevalence levels on their mud shrimp hosts and may strongly influence host ecology and biology. Currently, 54 species of bopyrids and eight species of ionids are known to parasitize ghost and mud shrimps. We present new taxonomic data on three species of ionids and ten species of bopyrids (nine previously described and one new to science), as well as on an undescribed species of nematode from an axiidean host. New locality and host records are given for all species. Our analysis of new material and review of museum specimens includes the description of the new species Acrobelione halimedae n. sp. from Austinogebia spinfrons (Haswell, 1881). We also provide an improved definition for the genus Pseudione Kossmann, 1881, based on morphological characters found in both sexes, and resolution of the type species, P. callianassae Kossmann, 1881. In our revision of Pseudione we erect a new genus, Robinione, and placed two species therein: R. overstreeti (Adkison Heard, 1995) and R. brattstroemi (Stuardo, Vega Cespedes, 1986). In addition, two other species are removed from Pseudione: P. compressa (Shiino, 1964) is moved to Ionella Bonnier, 1900, and P. panopei Pearse, 1947 is considered a synonym of Progebiophilus upogebiae (Hay, 1917). Bopyrid isopods represent a large, diverse taxon and our findings help clarify the taxonomy of those species found on ghost and mud shrimps.

  10. Extending the southern range of four shrimps (Crustacea: Decapoda: Stenopodidae, Hippolytidae and Alpheidae) in southwestern Atlantic (27o S) and confirming the presence of Mediterranean Stenopus spinosus Risso, 1827 in Brazil.

    PubMed

    Giraldes, Bruno Welter; Freire, Andrea Santarosa

    2015-06-12

    In subtidal zones, certain shrimp species with cryptic behaviour represent a gap in the biodiversity description in many places in the world. This study extends the southern limit of Stenopus hispidus (Oliver, 1811), Alpheus formosus Gibbes, 1850, Alpheus cf. packardii Kingsley, 1880 and Lysmata ankeri Rhyne & Lin, 2006 to Santa Catarina State-Brazil, 27oS. The results also confirm the new occurrence of Stenopus spinosus Risso, 1827 in Brazilian waters. All specimens were collected by scuba diving from rocky islands between 3 and 25 meters depth. We present for each species certain taxonomic features in colour images that will help to identify these decapods in situ in further monitoring programs.

  11. Reappraisal of the two axiid genera Manaxius Kensley, 2003 and Calaxidium Sakai, 2014, and description of a new species of Calaxius Sakai & de Saint Laurent, 1989 from French Polynesia, Southwest Pacific
    (Crustacea: Decapoda: Axiidea).

    PubMed

    Komai, Tomoyuki

    2016-04-07

    Discovery of an undescribed species of axiid shrimp from French Polynesia, Southwest Pacific, led the author to assess the taxonomic status of the two nominal genera, Manaxius Kensley, 2003 and Calaxidium Sakai, 2014. As a result, these two genera are synonymized under Calaxius Sakai & de Saint Laurent, 1989, because there are no significant differences in generic characters among the three taxa. An emended generic diagnosis of Calaxius is presented. The new species, Calaxius poupini, is morphologically similar to C. euophthalmus (De Man, 1905), C. izuensis Komai, 2011, C. kensleyi Clark, Galil & Poore, 2007, C. mimasensis (Sakai, 1967), C. pailoloensis (Rathbun, 1906) and C. sibogae (De Man, 1925), but the poorly developed armature on the ventral margin of each cheliped merus distinguishes the new species from the other six allied species. Some points of taxonomic confusion relating to Calaxius are clarified.

  12. A new species of the deep-sea spongicolid genus Spongicoloides (Crustacea, Decapoda, Stenopodidea) and a new species of the glass sponge genus Corbitella (Hexactinellida, Lyssacinosida, Euplectellidae) from a seamount near the Mariana Trench, with a novel commensal relationship between the two genera

    NASA Astrophysics Data System (ADS)

    Kou, Qi; Gong, Lin; Li, Xinzheng

    2018-05-01

    A new species of the deep-sea spongicolid genus Spongicoloides Hansen, 1908 and a new species of the euplectellid genus Corbitella Gray, 1867 are described and illustrated based on the material recently collected by the remotely operated vehicle 'Faxian' at a seamount near the Mariana Trench. The new deep-sea spongicolid species can be distinguished from the congeneric species by a series of morphological features and the validity of the new species was supported by the molecular phylogenetic analysis. By means of the microscleres of regular hexasters and onychohexasters, the new sponge species can easily be distinguished from other Corbitella species. The new euplectellid sponge species is the host of the new spongicolid shrimp species: this is the first discovery of an association between Spongicoloides and Corbitella. The present study increases the species diversity of both genera as well as yielding new insight into the commensal relationships between spongicolid shrimps and their sponge hosts.

  13. The Impact of Marine Protected Areas on Reef-Wide Population Structure and Fishing-Induced Phenotypes in Coral-Reef Fishes

    NASA Astrophysics Data System (ADS)

    Fidler, Robert Young, III

    targeted for food in the region (Acanthurus nigrofuscus, Ctenochaetus striatus, and Parupeneus multifasciatus) exhibited greater Linf, lower K, or both characteristics inside at least one MPA compared to populations in adjacent, fished reefs. Life-history shifts were concentrated in the oldest and largest MPAs, but occurred at least once in each of the five MPAs that were examined. A fourth species harvested for food (Ctenochaetus binotatus), as well as a species targeted for the aquarium trade (Zebrasoma scopas) and a non-target species (Plectroglyphidodon lacrymatus) did not exhibit differential phenotypes between MPAs and fished reefs. The relatively high frequency of alterations to life-history characteristics across MPAs in harvested species suggests that observed changes in the density and size-structure of harvested fish populations inside MPAs are likely driven by spatial disparities in fishing pressure, and are the result of phenotypic changes rather than increased longevity.