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1

[New metacercariae of the genus Tylodelphys (Trematoda, Diplostomatidae) in lacustrine populations of Galaxias maculatus (Teleostei, Galaxiidae)].  

PubMed

Metacercariae of three new species of Tylodelphys (Trematoda, Diplostomatidae) were found in the brain of Galaxias maculatus (Teleostei, Galaxiidae), at the Meliquina Lake, Neuquen Province, Argentina. These metacercariae are morphologically described as Tylodelphys argentinus n. sp., Tylodelphys barilochensis n. sp. and Tylodelphys crubensis n. sp. This is the first time that a stage of genus Tylodelphys is mentioned parasitizing Galaxias maculatus. Metacercariae of T. barilochen sis n. sp. were also found in G. maculatus brain at the Perito Moreno Lake, Rio Negro Province, Argentina. PMID:1306987

Quaggiotto, E A; Valverde, F

1992-01-01

2

[Contribution to the morphological description of Tylodelphys barilochensis and Tylodelphys crubensis (Trematoda, Diplostomidae) encephalon parasites of Galaxias maculatus (Teleostei, Galaxiidae)].  

PubMed

Taxonomic characteristics, for species identification, of metacercarie of T. barilochensis and T. crubensis found in the encephalon of the fish Galaxias maculatus, not included in the original descriptions, particularly those concerning to the excretory system, are described. PMID:9640687

Flores, V

1997-01-01

3

Aspects of the biology of Galaxias maculatus.  

PubMed

The biology of three landlocked and a riverine population of Galaxias maculatus were examined in western Victoria, Australia. All systems supported reproducing populations of these fish, including Lake Corangamite which had salinities that on occasion reached 82. Spawning sites in Lake Corangamite were located in adjacent tributaries and not in the main lake as was the case for other populations. The smallest fish were found in the fresh water Lake Purrumbete and the largest in the hypersaline Lake Corangamite. The size at which 50% of the population attained sexual maturity varied across sites, with fish maturing at a smaller size in Lake Purrumbete, followed by the Merri River, Lake Bullen Merri and Lake Corangamite. Condition was higher in the freshwater Lake Purrumbete and there was no relationship between condition and temperature, conductivity, turbidity and pH; but there was a positive relationship between condition and dissolved oxygen. Length frequency analysis suggested that the majority of fishes live for a year. PMID:22880739

Laurenson, L J B; French, R P; Jones, P; Ierodiaconou, D; Gray, S; Versace, V L; Rattray, A; Brown, S; Monk, J

2012-08-01

4

Attraction of migratory inanga (Galaxias maculatus) and koaro (Galaxias brevipinnis) juveniles to adult galaxiid odours  

Microsoft Academic Search

The response of migratory galaxiid juveniles, inanga (Galaxias maculatus) and koaro (G. brevipinnis), to the odours of adult galaxiids was tested in a two?choice chamber apparatus. Both conspecific and heterospecific odours were tested. Inanga juveniles were attracted to adult inanga (G. maculatus), banded kokopu (G. fasciatus), and koaro (G. brevipinnis) odours. However, they were not attracted to odours from common

Cindy F. Baker; Brendan J. Hicks

2003-01-01

5

Stages in the normal development of Galaxias maculatus attenuatus (Jenyns)  

Microsoft Academic Search

The sequence of embryonic development is described for Galaxias maculatus attenuatus (Jenyns). Standard stages are described and the rate of development at two different constant temperatures is given. Field results are compared with these data. It appears that G. m. attenuatus is very temperature labile in its development, an adaptation of high survival value in the habitat in which the

Vivienne Benzie

1968-01-01

6

Laboratory culture of Galaxias maculatus and potential applications  

Microsoft Academic Search

Galaxias maculatus has considerable potential as a laboratory animal. Laboratory techniques used to maintain, artificially spawn, hatch, and rear this New Zealand native freshwater fish are described. Potential research applications for the fish, the eggs, and the larvae are outlined. The development of the larvae is described.

Charles P. Mitchell

1989-01-01

7

Habitat related variations in fatty acids of catadromous Galaxias maculatus  

Microsoft Academic Search

The fatty acid profile of the galaxiid fish Galaxias maculatus (Salmoniformes) collected from an estuarine habitat (a river mouth), a freshwater creek and two land-locked freshwater lakes in Victoria, Australia, were investigated with a view to evaluating habitat influences on the fatty acid profile. Fish from the freshwater creek were unpigmented, fresh-run juveniles (referred to as whitebait), the others adult

Sena S. De Silva; Rasanthi M. Gunasekera; Chris M. Austin; Graeme Allinson

1998-01-01

8

A novel oxyconforming response in the freshwater fish Galaxias maculatus.  

PubMed

How fish oxygen consumption is modulated by external PO(2) has long been a matter of interest, yet is an experimentally complicated question to answer. In this study closed and semi-closed respirometry were used to evaluate the oxygen consumption rate of the scaleless galaxiid fish, inanga (Galaxias maculatus) as a function of decreasing external PO(2). Both respirometry techniques showed that as environmental oxygen levels declined, oxygen consumption rates also decreased. At no point did inanga regulate oxygen consumption. This is strong evidence that inanga is an oxyconformer. Partitioned respirometry experiments showed that skin plays an important role in oxygen uptake in this fish species, and cutaneous oxygen uptake may have an important role in shaping the oxygen consumption response to hypoxia. PMID:22138470

Urbina, Mauricio A; Glover, Chris N; Forster, Malcolm E

2012-03-01

9

Effects of Galaxias maculatus on nutrient dynamics and phytoplankton biomass in a North Patagonian oligotrophic lake  

Microsoft Academic Search

In this study we analysed the effects of Galaxias maculatus, a landlocked small fish species, on nutrient dynamics, and the consequent effects on phytoplankton biomass of an oligotrophic North Patagonian lake. We performed field and laboratory experiments in order to explore nutrient release by G. maculatus with increasing fish biomass and body size, and the resulting phytoplankton responses. Our results

Mariana Reissig; Claudia P. Queimali; Esteban G. Balseiro

2003-01-01

10

Variation in Life History of Land-Locked Lacustrine and Riverine Populations of Galaxias maculatus (Jenyns 1842) in Western Australia  

Microsoft Academic Search

Galaxias maculatus is one of the most naturally widely distributed species in the world yet there is no published literature on the biology of Western Australian populations. Galaxias maculatus in the rivers of the south coast of Western Australia inhabit an environment that is variable and at times unpredictable. By examining trends in gonadal development, lengths at first maturity, growth

Andrew Chapman; David L. Morgan; Stephen J. Beatty; Howard S. Gill

2006-01-01

11

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

Microsoft Academic Search

BACKGROUND: The dynamic geological and climatic histories of temperate South America have played important roles in shaping the contemporary distributions and genetic diversity of endemic freshwater species. We use mitochondria and nuclear sequence variation to investigate the consequences of mountain barriers and Quaternary glacial cycles for patterns of genetic diversity in the diadromous fish Galaxias maculatus in Patagonia (~300 individuals

Tyler S Zemlak; Evelyn M Habit; Sandra J Walde; Cecilia Carrea; Daniel E Ruzzante

2010-01-01

12

Ontogenetic shifts in the diet of Galaxias maculatus (Galaxiidae) and Odontesthes microlepidotus (Atherinidae)  

Microsoft Academic Search

The feeding habits ofGalaxias maculatus (Galaxiidae) andOdontesthes microlepidotus (Atherinidae) larvae and juveniles were studied in an Araucanian lake of Argentina. Fish specimens were grouped, on the basis of the percentage of each food category found in their gut, using multivariate methods. These groups of fishes showed significant differences in average total length. Positive correlations between prey size and fish length

Patricia M. Cervellini; Miguel A. Battini; Victor E. Cussac

1993-01-01

13

Intralacustrine movements of Galaxias maculatus (Galaxiidae) and Ondontesthes microlepidotus (Atherinidae) during their early life history  

Microsoft Academic Search

Galaxias maculatus and Odontesthes microlepidotus undertook significant habitat shifts in a small Araucanian lake during their early life history. After hatching in the littoral zone, free embryos migrate to the limnetic zone. Later, larvae return to the littoral. A third movement, littoral-limnetic, is suggested through acoustic records of fish in the limnetic zone which correspond with the growth curve of

Victor E. Cussac; Patricia M. Cervellini; Miguel A. Battini

1992-01-01

14

The life history of Galaxias vulgaris Stokell, with a comparison with G. maculatus attenuatus  

Microsoft Academic Search

Galaxias vulgaris Stokell is a totally freshwater fish species and the adults usually live a cryptic life under stones. The life history of this species, with special emphasis on its embryology, growth rate, and sex ratio, is described. Comparisons are made with other members of the family Galaxiidae, especially G. maculatus attenuatus

Vivienne Benzie

1968-01-01

15

A consideration of the whitebait stage of Galaxias maculatus attenuatus (Jenyns)  

Microsoft Academic Search

The size composition of a season's catch of Galaxias maculatus attenuatus (Jenyns) whitebait is given. An analysis of consecutive catches shows that there is no overall increase in the size of the whitebait caught. This supports the theory that these fish have reached a physiological stage at which they migrate up accessible freshwater streams. The subsequent changes are so great

Vivienne Benzie

1968-01-01

16

In?stream habitat suitability criteria for feeding inanga (Galaxias maculatus)  

Microsoft Academic Search

Inanga (Galaxias maculatus Jenyns) are the basis of an important recreational and commercial freshwater fishery that has declined over the past 100 years, probably because of habitat degradation in developed areas. Maintenance of suitable stream flows for inanga is one means of protecting the fishery. Observations of habitat use by drift?feeding inanga were made in three streams. Most feeding inanga

I. G. Jowett

2002-01-01

17

Acanthocephalus tumescens (Acanthocephala, Echinorhynchidae) in Galaxias maculatus (Pisces, Galaxiidae) of Lake Gutiérrez, Patagonia, Argentina.  

PubMed

The seasonal distribution of Acanthocephalus tumescens (Acanthocephala : Echinorhynchidae) among Galaxias maculatus (Pisces : Galaxiidae) in Lake Gutiérrez was studied from March 1994 to June 1996. Acanthocephalus tumescens always occurs in the intestine, has an overdispersed frequency distribution, a similar proportion of sexes, and females are larger than males. Mean intensity and prevalence are low and increase with host length. The pattern of the infection shows seasonality, with recruitment in winter and a reproductive period during spring-summer. PMID:10701591

Trejo, A; Semenas, L; Viozzi, G

2000-02-01

18

Effect of the selective feeding of Galaxias maculatus (Salmoniformes, Galaxiidae) on zooplankton of a South Andes lake  

Microsoft Academic Search

The effect of larval and juvenile predation ofGalaxias maculatus on a natural small-sized zooplankton was studied in a South Andes lake. Field data of zooplankton density and composition were combined with fish gut content analysis during a spring-summer season. Results showed thatGalaxias early stages ingested mostly planktonic preys. A shift was observed in prey electivity: larvae preferred copepod nauplii whereas

Beatriz E. Modenutti; Esteban G. Balseiro; Patricia M. Cervellini

1993-01-01

19

Post-settlement migratory behaviour and growth-related costs in two diadromous fish species, Galaxias maculatus and Galaxias brevipinnis.  

PubMed

The physiological challenges incurred during the transition from sea to fresh water and the constraints they place on the rate at which the common galaxiid Galaxias maculatus and the climbing galaxiid Galaxias brevipinnis can migrate from marine to freshwater habitats were examined. The duration of the marine to freshwater transition, the relationship between post-settlement age (PSA) and standard length (L(S)) as a proxy for energetic costs incurred during settlement and the potential effects of estuary geomorphology on migratory behaviour was investigated. Rate of upstream migration after settlement was not uniform. Upstream migration rate was slowest directly after settlement and increased with increasing PSA and distance from the river mouth, indicating a delay in upstream migration by newly recruited galaxiids. L(s) did not increase with age, at least within the first 21 days post settlement. These patterns were consistent for both species, in spite of differences in their life histories, across the recruitment season, despite seasonal variation in recruit size, and among estuaries with different properties. The results suggest that the timing and speed of migratory behaviour primarily reflect physiological constraints. Given the duration of residency of these species in estuaries, this study indicates that estuaries are critical transitional habitats for diadromous fishes during their migration from marine to freshwater habitats. PMID:20738553

Jung, C A; Barbee, N C; Swearer, S E

2009-08-01

20

Infection of Myxobolus galaxii (Myxozoa) in Galaxias maculatus (Osmeriformes: Galaxiidae) from northwestern Patagonian Andean lakes (Argentina).  

PubMed

The infection of Myxobolus galaxii Szidat, 1953, from the musculature and abdominal organs of northwestern Patagonian Galaxias maculatus is described. Plasmodia are histozoic and intercellular. Spores are pyriform in valvar view and biconvex in sutural view, with 4-9 edge notches in the sutural line, varying in shape within the same plasmodium. Myxobolus galaxii was detected in fish from 7 of 17 Andean Patagonian lakes, with prevalences ranging between 2 and 17%. A repeating pattern of summer increment in prevalence was observed, which could be explained by the ontogenetic migratory movements of the fish in Lake Gutiérrez. Also, accumulation of plasmodia through the life span of fish was detected. PMID:17539428

Flores, Verónica; Viozzi, Gustavo

2007-04-01

21

Ten novel microsatellite loci characterized for a remarkably widespread fish: Galaxias maculatus (Galaxiidae).  

PubMed

Ten polymorphic microsatellite markers (five tetra-, one compound tetra-, one octa- and three dinucleotides) were isolated and characterized for Galaxias maculatus, a fish species widely distributed in the Southern Hemisphere. Markers were tested in 89 individual samples from a single location and the number of alleles ranged between 2 and 28. Observed and expected heterozygosities ranged from 0.103 to 0.910 and 0.098 to 0.935 respectively. No evidence was detected for either linkage disequilibrium (P-values?>?0.05 for each locus pair) or deviations from HWE (P-values?>?0.05 for every loci). PMID:21564945

Carrea, Cecilia; Paterson, Ian G; Cussac, Victor E; Ruzzante, Daniel E

2009-11-01

22

Myxidium biliare sp. n. (Myxozoa) from gall bladder of Galaxias maculatus (Osmeriformes: Galaxiidae) in Patagonia (Argentina).  

PubMed

Myxidium biliare sp. n., a new myxosporean species parasitizing the gall bladder of Galaxias maculatus (Jenyns), in Patagonia, is described. Its coelozoic plasmodia were floating free in the bile. Spores are fusiform 13.7 +/- 0.9 microm long and 6.9 +/- 0.6 microm wide, with rounded ends in frontal view and slightly pointed ends in sutural view; shell with ridges and sinuous sutural line. Both maximum prevalence and maximum percentage of immature plasmodia occurred in summer. In winter the prevalence and the percentage of immature plasmodia fell to their lowest values. Prevalence was independent of host sex but increased with host length. Prevalence in 15 Patagonian Andean lakes (situated from 39 degrees 25'S to 41 degrees 30'S) ranged between 4.2% and 70%. PMID:14535344

Viozzi, Gustavo P; Flores, Verónica R

2003-09-01

23

Differential piscivory of the native Percichthys trucha and exotic salmonids upon the native forage fish Galaxias maculatus in Patagonian Andean lakes  

Microsoft Academic Search

The present paper analyses predation patterns, of Percichthys trucha and salmonid fish upon Galaxias maculatus in five lakes of northern Patagonia with differing community and environmental characteristics. Tank experiments were performed to evaluate relative efficiency of native and exotic predators of G. maculatus under treatments with and without cover (aquatic vegetation). Important differences were found between predators with regards to

Patricio J. Macchi; Miguel A. Pascual; Pablo H. Vigliano

2007-01-01

24

Extreme Intraspecific Mitochondrial DNA Sequence Divergence in Galaxias maculatus(Osteichthys: Galaxiidae), One of the World's Most Widespread Freshwater Fish  

Microsoft Academic Search

Biogeographic controversies surrounding the widespread freshwater fish,Galaxias maculatus,were addressed with DNA sequence data. Mitochondrial cytochromeband 16S rRNA sequences were obtained from representatives of six populations of this species. Substantial levels of cytochromeb(maximum 14.6%) and 16S rRNA sequence divergence (maximum 6.0%) were detected between western Pacific (Tasmania–New Zealand) and South American (Chile–Falkland Islands) haplotypes. A considerable level of divergence was also

Jonathan M. Waters; Christopher P. Burridge

1999-01-01

25

Allocreadium pichi n. sp. (Trematoda: Allocreadiidae) in Galaxias maculatus (Osteichthyes: Galaxiidae) from Lake Moreno in Patagonia (Argentina).  

PubMed

Allocreadium pichi n. sp. (Trematoda: Allocreadiidae) is described from the intestine of Galaxias maculatus (Osteichthyes: Galaxiidae) from Moreno Lake in Patagonia, Argentina. This species is distinguished from A. patagonicum Shimazu, Urawa & Coria, 2000, the other species recorded in the area, by its smaller body size, the diagonal position of the testes and different ratios of the suckers, testes and cirrus-sac in relation to body size. In addition, the synonymy of A. patagonicum with Polylekithum percai Ostrowski de Núñez, Brugni & Viozzi, 2000 is proposed herein. PMID:15218369

Flores, Verónica R; Brugni, Norma; Ostrowski de Núñez, Margarita

2004-07-01

26

A new genus of dactylogyrid from the gills of Galaxias maculatus (Osmeriformes: Galaxiidae) in Maullín Basin, Patagonia, Chile.  

PubMed

During a parasitological survey of Galaxias maculatus (Jenyns, 1842) in the Maullín Basin (Chilean Patagonia), specimens of a new species of Monogenea were collected from the gills. This species is described as the only member of a proposed new genus, Inserotrema n. gen. (Dactylogyridae, Ancyrocephalinae), characterized by similar hooks with 2 subunits, overlapping gonads, coiled cirrus with counterclockwise rings, articulated accessory piece formed by 2 parts, a needlelike sclerite threading the distal part of the MCO, and a sclerotized midventral vagina. This new genus is proposed for dactylogyrids from gills of galaxiids (Galaxiidae). Inserotrema puyei n. sp. infects gills of G. maculatus from Llanquihue Lake, Maullín River, and Maullín Estuary. This is the first species of Ancyrocephalinae described from gills of a galaxiid. PMID:17626345

Viozzi, Gustavo P; Marin, Sandra L; Carvajal, Juan; Brugni, Norma; Mancilla, Melinka

2007-06-01

27

Do environmental differences between lakes in northwestern Argentinean Patagonia affect the infection of Philureter trigoniopsis (monogenea) in Galaxias maculatus (osmeriformes)?  

PubMed

Philureter trigoniopsis is the only parasite found in the ureters and urinary bladder of Galaxias maculatus in Patagonian Andean lakes. The dynamics of this endoparasitic monogenean were studied in Lake Gutiérrez, a body of water with scarce shoreline vegetation, where the host has an annual cycle of migration to the deep pelagic zone of the lake. To compare variations of the infection related to differences between lakes, G. maculatus specimens were sampled monthly with baited traps from September 1998 to November 1999 in Lake Moreno, which is an oligotrophic body of water with emergent shoreline vegetation and where the fish do not migrate to the deep pelagic areas of the lake. In addition, data for summer infections of P. trigoniopsis from 10 Andean Patagonian lakes that differ in aquatic vegetation, depth, and area were compared. In Lake Moreno prevalence of P. trigoniopsis showed a seasonal pattern, with 1-yr-old fish exhibiting the highest values of prevalence and mean intensity. Negative correlations between water temperature and prevalence and between age of fish and abundance were found. Our results suggest that age of fish may be the main factor structuring the distribution of P. trigoniosis in populations of G. maculatus. At the regional level the relationship between the infection and the characteristics of the lakes was also observed, with prevalence and mean intensity of P. trigoniopsis in G. maculatus higher in large deep lakes without macrophytes. PMID:18576893

Viozzi, G P; Semenas, L G

2009-02-01

28

A new genus of Cystidicolid nematode from the stomach of Galaxias maculatus (Osmeriformes: Galaxiidae) in Patagonia (Argentina).  

PubMed

During a parasitological survey of Galaxias maculatus (Jenyns) from Patagonian Andean Lakes, specimens of a new species of nematode were collected from the stomach of fish and studied by light and scanning electron microscopy. This species is described as the only member of a newly proposed genus of Cystidicolidae by having oral opening dorsoventrally elongated, 2 lateral pseudolabia, 4 cephalic papillae, stoma (vestibule) elongated, esophagus divided into anterior muscular and posterior glandular sections, and caudal alae in males. Placonema n. gen. (Habronematoidea, Cystidicolidae) is characterized by the combination of the following features: oral opening dorsoventrally elongated demarcated by 4 sclerotized plates and 2 well-developed pseudolabia projected to the buccal cavity, each pseudolabium with conspicuous, conical, anterior protuberances. Four cephalic papillae and deirids simple. Male with caudal alae, area rugosa absent, 4 pairs of preanal papillae, unpaired papilla present on anterior cloacal lip, and 6 pairs of postanal papillae. Larvigerous eggs without filaments. Placonema pataguense n. gen. n. sp. infects the stomach of G. maculatus from Lake Patagua (Patagonia, Argentina) and is the first species of Cystidicolidae described from G. maculatus. PMID:18652524

Brugni, Norma L; Viozzi, Gustavo P; Fernández, María V; Vega, Rocío M

2009-02-01

29

Impact of a caged-trout farm on parasites of Galaxias maculatus in Lake Moreno, southern Argentina.  

PubMed

The present study was conducted to determine the impact of a caged-trout farm on the helminth parasites of the wild fish puyen chico (Galaxias maculatus) in Lake Moreno, southern Argentina. Samples of water, fish (G. maculatus), and snails (Heleobia hatcheri) were taken at 4 sampling stations in January 2001. Wild fish were parasitized by 8 helminth species, all of which are endemic in the region; therefore, the farm did not introduce any helminth parasite to G. maculatus. Fish captured near the farm were not infected by the digenean Steganoderma szidati, whereas the abundance of the digenean Acanthostomoides apophalliformis in these fish was significantly lower than that in fish captured away from the farm. This lower abundance may be explained by the absence in this area of the snail H. hatcheri, the parasite's first intermediate host, because of the effect of sediments and ammonium produced by the farm. To our knowledge, this is the first study in the Americas linking fish-farm pollution to helminth parasites in wild fish. PMID:16108574

Revenga, Jorge E; Torres, Patricio F; Baiz, Miguel

2005-06-01

30

Steganoderma szidati n. sp. (Trematoda: Zoogonidae) from Galaxias maculatus (Jenyns) and G. platei Steindachner in Patagonia, Argentina.  

PubMed

Steganoderma szidati n. sp. is described from the intestine of two freshwater fishes, Galaxias maculatus and G. platei (Galaxiidae), from Andean lakes in Patagonia, Argentina. This freshwater zoogonid species fits in the genus Steganoderma (sensu Bray, 1987) because of the length of the caeca and the position of the vitelline follicles. The new species is characterised by possessing 6-13 vitelline follicles situated between the anterior margin of the ventral sucker and the posterior margin of the testis. The gonads are in the anterior hindbody and the ovary is anterior to the right testis. The cirrus has two conspicuous spines at its distal end, and the seminal vesicle always exhibits a constriction. The excretory vesicle never reaches the level of the posterior margin of the testes. PMID:10845652

Viozzi, G; Flores, V; Ostrowski de Núñez, M

2000-07-01

31

Extended incubation affects larval morphology, hatching success and starvation resistance in a terrestrially spawning fish, Galaxias maculatus (Jenyns 1842).  

PubMed

The effect of extended incubation (delayed hatching) on larval morphology in the terrestrially spawning common galaxias Galaxias maculatus was investigated by inducing larvae to hatch 1 and 2 weeks after the normal 2 week incubation period. After 1 week of extended incubation, larvae were larger (longer in standard length, L(S), and greater in body depth) compared to controls (larvae that experienced normal incubation durations). After 2 weeks of extended incubation, larvae were smaller (shorter in L(S) and smaller in body depth) than larvae that experienced 1 week of extended incubation. Furthermore, eye area increased while yolk-sac size decreased monotonically with increasing incubation duration. These results suggest that larvae experiencing long periods of extended incubation are using somatic tissue to meet their metabolic demands. Larvae that experienced 2 weeks of extended incubation succumbed to starvation sooner than control larvae, but hatching success was not significantly different. Temperature mediated the effect of extended incubation on the morphology of larvae at hatching, most likely, through its effects on developmental rate and efficiency of yolk utilization. This study demonstrates some of the consequences of terrestrial spawning with extended incubation, which will assist in determining why this intriguing behaviour has evolved several times in a diverse range of taxa. PMID:21967585

Semmens, D; Swearer, S E

2011-10-01

32

Extreme intraspecific mitochondrial DNA sequence divergence in Galaxias maculatus (Osteichthys: Galaxiidae), one of the world's most widespread freshwater fish.  

PubMed

Biogeographic controversies surrounding the widespread freshwater fish, Galaxias maculatus, were addressed with DNA sequence data. Mitochondrial cytochrome b and 16S rRNA sequences were obtained from representatives of six populations of this species. Substantial levels of cytochrome b (maximum 14.6%) and 16S rRNA sequence divergence (maximum 6.0%) were detected between western Pacific (Tasmania-New Zealand) and South American (Chile-Falkland Islands) haplotypes. A considerable level of divergence was also detected between Tasmanian and New Zealand haplotypes (maximum 5.1%) and within and among Chilean and Falkland Island G. maculatus (maximum 3. 8%). The phylogenetic structure of haplotypes conflicts with the accepted pattern of continental fragmentation. Molecular clock calibrations suggest that haplotype divergences postdate the fragmentation of Gondwana. These findings point to marine dispersal rather than ancient vicariance as an explanation for the wide distribution. The phylogenetic structure of South American haplotypes was not consistent with their geographic distribution. We consider factors such as population divergence, population size, dispersal, secondary contact, and philopatry as potential causes of the high level of mtDNA nucleotide diversity in this species. PMID:10082606

Waters, J M; Burridge, C P

1999-02-01

33

Population dynamics of Philureter trigoniopsis (Monogenea: Ancyrocephalinae) from urinary organs of Galaxias maculatus (Osmeriformes: Galaxiidae) in a cold temperate Andean Patagonian lake (Argentina).  

PubMed

Philureter trigoniopsis parasitizes the ureters and urinary bladder of Galaxias maculatus in Patagonian Andean lakes. To investigate factors associated with variation in the prevalence and intensity of this monogenean, fish were sampled periodically over 2 yr in Lake Gutiérrez. Prevalence and mean intensity are higher in smaller fishes than in larger ones. A seasonal pattern was observed, with peak recruitment and peak mean intensity occurring in early spring (September), followed by lows in late summer (January-February). Galaxias maculatus length classes are spatially segregated due to seasonal migrations, so the annual infection cycle is characterized by higher prevalence and intensity from late winter to early summer in the smaller fish from the deep zone of the lake. PMID:16539018

Viozzi, Gustavo P; Semenas, Liliana G; Gutiérrez, Pablo

2005-12-01

34

Philureter trigoniopsis, a new genus and species (Dactylogyridae, Ancyrocephalinae) from the ureters and urinary bladder of Galaxias maculatus (Osmeriformes: Galaxiidae) in Patagonia (Argentina).  

PubMed

The monotypic Philureter n. gen. (Ancyrocephalinae; Dactylogyridae) is proposed to accommodate Philureter trigoniopsis n. sp. with the following features: presence of a cuplike ventral haptor armed with 14 hooks and 2 anchor/bar complexes; dorsal pair of anchors poorly defined and variable in shape, 1 frequently absent; tandem, intercecal gonads, testis bilaterally lobulated. Philureter trigoniopsis n. sp. is described from the ureters and urinary bladder of Galaxias maculatus (Jenyns, 1842) (Osmeriformes) in Patagonian Andean lakes, Argentina. PMID:11318570

Viozzi, G P; Gutiérrez, P A

2001-04-01

35

Infections by helminth parasites in "puyenes", Galaxias maculatus (Galaxiidae, Salmoniformes), from Southern Argentina with special reference to Tylodelphys barilochensis (Digenea, Platyhelminthes).  

PubMed

The occurrence of Tylodelphys barilochensis, Acanthostomoides apophalliformis, Contracaecum sp. and Camallanus corderoi infecting Galaxias maculatus ("puyenes") was quantified for the first time in Lake Nahuel Huapi, southern Argentina. T. barilochensis was recorded in this lake for the first time. The role of G. maculatus population in transmission of parasites to the salmonids is more important for Contracaecum sp. (prevalence 14-34%) and A. apophalliformis (prevalence 30-54%) than for C. corderoi (prevalence 6-8%). The absence of Diphyllobothrium spp. in samples shows that the G. maculatus population does not play any role in the life cycles of these important zoonotic parasites. The sex of the host had no effect on T. barilochensis abundance. Statistical differences in T. barilochensis abundance between "puyenes" of the same size class between sampling stations and positive correlation between prevalence of infected snails and T. barilochensis abundance in fish suggest that different stocks have been sampled. Factors influencing T. barilochensis abundance are discussed. PMID:10464401

Revenga, J; Scheinert, P

1999-01-01

36

Migration of galaxias maculatus (Jenyns) (galaxiidae, pisces) in Valdivia Estuary, Chile  

Microsoft Academic Search

A migratory pattern ofG. maculatus as a diadromic and marginally catadromic, is similar to that in New Zealand and Australia. Their migratory relationship with the sea suggests that their route of dispersal in the tertiary might have been transantartic (western Antartica) and not caused by the “West Wind Drift” as suggested by other authors.

Campos C. Hugo

1973-01-01

37

Two further new species of Galaxias (Teleostei: Galaxiidae) from the Taieri River, southern New Zealand  

Microsoft Academic Search

Two new species of Galaxias have overlapping distributions in the lower Taieri River catchment, Otago, although not as yet found in sympatry. Galaxias pullus n.sp. is known from several tributaries of the Waipori River up? and downstream of Lake Mahinerangi, and also from a tributary of the Waitahuna, part of the Clutha River catchment. Galaxias eldoni n.sp. comes from several

R. M. McDowall

1997-01-01

38

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

PubMed

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

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

2013-04-01

39

A new species of Galaxias (Teleostei: Galaxiidae) from the Mackenzie Basin, New Zealand  

Microsoft Academic Search

Galaxias macronasus n. sp. is described from three small upper tributaries of the Waitaki River System, Mackenzie Basin, central eastern South Island. It is distinctive in having a prominently rounded snout profile, with eyes well below profile, only 12–14 caudal fin rays, and 4–6, usually 5, pelvic fin rays. Morphologically, the new species most closely resembles G. paucispondylus and G.

R. M. McDowall; J. M. Waters

2003-01-01

40

Description and redescription of Galaxias species (Teleostei: Galaxiidae) from Otago and Southland  

Microsoft Academic Search

There are two distinct genotypes and morphotypes of fish belonging to Galaxias vulgaris Stokell (sensu lato) in narrow sympatry in Healy Stream, a tributary of the Kye Burn in the Taieri River system, northeastern Otago. Therefore the present taxonomy of the species misrepresents the diversity of these fish. Analysis of allozymes using gel electrophoresis indicates at least four groups of

R. M. McDowall; G. P. Wallis

1996-01-01

41

Emigrating larvae of koaro, Galaxias brevipinnis Günther (Teleostei: Galaxiidae), from the Otira River, New Zealand  

Microsoft Academic Search

Fish larvae were collected in stream benthic invertebrate drift nets from the Otira River, near Arthur's Pass, New Zealand during a study of benthic drift. They are identified as probably those of koaro (Galaxias brevipinnis Gunther) on the basis of estimates of myomere counts (indicating Galaxiidae or Retropinnidae); by a process of elimination of likely species on the basis of

R. M. McDowall; A. M. Suren

1995-01-01

42

Ailinella mirabilis gen. n., sp. n. (eucestoda: pseudophyllidea) from Galaxias maculatus (Pisces: Galaxiidae) in the Andean-Patagonian region of Argentina.  

PubMed

Ailinella gen. n. (Pseudophyllidea: Triaenophoridae) is proposed to accommodate Ailinella mirabilis sp. n. from Galaxias maculatus (Jenyns, 1842), a freshwater fish inhabiting the Andean lakes in Argentinean Patagonia. Ailinella belongs to the Triaenophoridae because it has a marginal genital pore, a follicular vitelline gland, and a ventral uterine pore. The new genus can be distinguished from other triaenophorids by the following combination of characters: a small body size, a low number of proglottides, which are longer than wide, a truncated pyramidal to globular scolex, a rectangular apical disc, presence of the neck, lack of internal longitudinal musculature separating the cortex from the medulla, testes distributed in one central field surrounding the ovary laterally and posteriorly, the vagina predominantly anterior to the cirrus sac, vitelline follicles circum-medullary, the genital pores post-equatorial, a saccate uterus, and operculate eggs. Blade-like spiniform microtriches were present on all tegument surfaces, and tumuli on all surfaces of the scolex and the anterior surface of the neck. Microtriches were characterized according to their size and density, and tumuli according to their size, inter-tumulus distance and density. Ailinella mirabilis is the first cestode described from G. maculatus and the second triaenophorid species recorded from a South American freshwater fish. PMID:17256203

de Pertierra, Alicia A Gil; Semenas, Liliana G

2006-12-01

43

Population studies of Galaxias maculatus (Jenyns) (Osteichthys: Galaxiidae) in Chile with reference to the number of vertebrae  

Microsoft Academic Search

G. maculatus presenta dos poblaciones que difieren en el número de sus vertebras, en el sistema lacustre fluvial de Valdivia, Chile. Una población con un bajo número de vertebras esta en alopatria en los lagos y la otra con un alto número de vertebras esta en semi?alopatria en el estuario. Ambas poblaciones estan en simpatria en el río. Diferencias entre

Hugo Campos

1974-01-01

44

Should I stay or should I go?: Physiological, metabolic and biochemical consequences of voluntary emersion upon aquatic hypoxia in the scaleless fish Galaxias maculatus.  

PubMed

Hypoxia represents a significant challenge to most fish, forcing the development of behavioural, physiological and biochemical adaptations to survive. It has been previously shown that inanga (Galaxias maculatus) display a complex behavioural repertoire to escape aquatic hypoxia, finishing with the fish voluntarily emerging from the water and aerially respiring. In the present study we evaluated the physiological, metabolic and biochemical consequences of both aquatic hypoxia and emersion in inanga. Inanga successfully tolerated up to 6 h of aquatic hypoxia or emersion. Initially, this involved enhancing blood oxygen-carrying capacity, followed by the induction of anaerobic metabolism. Only minor changes were noted between emersed fish and those maintained in aquatic hypoxia, with the latter group displaying a higher mean cell haemoglobin content and a reduced haematocrit after 6 h. Calculations suggest that inanga exposed to both aquatic hypoxia and air reduced oxygen uptake and also increased anaerobic contribution to meet energy demands, but the extent of these changes was small compared with hypoxia-tolerant fish species. Overall, these findings add to previous studies suggesting that inanga are relatively poorly adapted to survive aquatic hypoxia. PMID:22645056

Urbina, Mauricio A; Glover, Chris N

2012-12-01

45

Relationship between fish size and metabolic rate in the oxyconforming inanga Galaxias maculatus reveals size-dependent strategies to withstand hypoxia.  

PubMed

The relationship between metabolic rate and body size in animals is unlikely to be a constant but is instead shaped by a variety of intrinsic (i.e., physiological) and extrinsic (i.e., environmental) factors. This study examined the effect of environmental oxygen tension on oxygen consumption as a function of body mass in the galaxiid fish, inanga (Galaxias maculatus). As an oxyconformer, this fish lacks overt intrinsic regulation of oxygen consumption, eliminating this as a factor affecting the scaling relationship at different oxygen tensions. The relationship between oxygen consumption rate and body size was best described by a power function, with an exponent of 0.82, higher than the theoretical values of 0.66 or 0.75. The value of this exponent was significantly altered by environmental P(O2), first increasing as P(O2) decreased and then declining at the lowest P(O2) tested. These data suggest that the scaling exponent is species specific and regulated by extrinsic factors. Furthermore, the external P(O2) at which fish lost equilibrium was related to fish size, an effect explained by the scaling of anaerobic capacity with fish mass. Therefore, although bigger fish were forced to depress aerobic metabolism more rapidly than small fish when exposed to progressive hypoxia, they were better able to enact anaerobic metabolism, potentially extending their survival in hypoxia. PMID:24241070

Urbina, Mauricio A; Glover, Chris N

2013-01-01

46

Introgressive hybridization between Galaxias depressiceps and Galaxias sp D (Teleostei: Galaxiidae) in Otago, New Zealand: Secondary contact mediated by water races  

Microsoft Academic Search

Central Otago (New Zealand) was the focus of an intense period ofgold mining in the late 19th century. Mining relied on high waterpressure for sluicing, often requiring extensive systems of water raceslinking headwaters over large distances. On Rough Ridge, races connectedheadwaters of Otago's two major river systems, the Taieri and theClutha. We employed genetic analysis of freshwater fish(Galaxias) populations to

Y. B. Esa; J. M. Waters; G. P. Wallis

2000-01-01

47

Isozyme analysis of Galaxias species (Teleostei: Galaxiidae) from the Taieri River, South Island, New Zealand: a species complex revealed  

Microsoft Academic Search

We examined genetic differentiation among 23 samples of non-migratory river galaxias from 17 streams in the Taieri River system, South Island, New Zealand. Four major genetic types were found, two of which occur in narrow sympatry in one location. These were compared with topotypical material representingGalaxias anomalusfrom the Clutha system (Otago) andG. vulgarisfrom the Waimakariri system (Canterbury) in order to

RICHARD M. ALLIBONE; TODD A. CROWL; JEAN M. HOLMES; TANIA M. KING; ROBERT M. McDOWALL; COLIN R. TOWNSEND; GRAHAM P. WALLIS

1996-01-01

48

Galaxias fossils from Miocene lake deposits, Otago, New Zealand: The earliest records of the Southern Hemisphere family Galaxiidae (Teleostei)  

Microsoft Academic Search

Galaxiid fishes are commonly assumed to exhibit a Gondwanan distribution, but little fossil evidence has been available to support or refute this assumption until now. Here we report on three species of fossil Galaxias, represented by exquisitely preserved, almost entire skeletons, together with jaw and skull fragments, from several Miocene lacustrine deposits in Otago, South Island, New Zealand. These are

D. E. Lee; R. M. McDowall; J. K. Lindqvist

2007-01-01

49

Genetic and morphological evidence for reproductive isolation between sympatric populations of Galaxias (Teleostei: Galaxiidae) in South Island, New Zealand  

Microsoft Academic Search

New Zealand's South Island houses a flock of closely related stream-resident fish taxa (Galaxias vulgaris sensu lato), including a number of species recently described on the basis of subtle morphological differences. The taxonomic status of some members of the species complex remains uncertain. This study examines the degree of reproductive isolation between recently recognized morphotypes from Southland (G. «southern», flatheads

JONATHAN M. WATERS; YUZINE B. ESA; GRAHAM P. WALLIS

2001-01-01

50

Biology of the western minnow, Galaxias occidentalis Ogilby (Teleostei : Galaxiidae), in a south-western Australian river  

Microsoft Academic Search

Larval, juvenile and adult Galaxias occidentalis were collected with a plankton net and a fine-meshed beach seine from the southern branch of the Collie River in south-western Australia at approximately monthly intervals between January 1984 and December 1986. Seasonal changes in the density of G. occidentalis in the main river and its tributary creeks, and concomitant changes in gonadosomatic index

L. J. Pen; I. C. Potter

1991-01-01

51

Galaxias gollumoides (Teleostei: Galaxiidae), a new fish species from Stewart Island, with notes on other non?migratory freshwater fishes present on the island  

Microsoft Academic Search

Galaxias gollumoides is a new species described from the Island Hill wetlands in central Stewart Island (east of Mason Bay), and the Robertson River in southern Stewart Island It is the first endemic Galaxias from the island, although another non?diadromous species, G depressiceps, is present there, as well as four diadromous species of Galaxias G gollumoides appears to belong to

R. M. McDowall; W. L. Chadderton

1999-01-01

52

Species composition of whitebait (Galaxiidae) fisheries in 12 Bay of Plenty rivers, New Zealand: Evidence for river mouth selection by juvenile Galaxias brevipinnis (Günther)  

Microsoft Academic Search

Galaxias maculatus dominated the whitebait catch in 11 of the 12 Bay of Plenty rivers studied. In four rivers, this species accounted for 84–99% of the catch. However, in seven other rivers, G. maculatus accounted for only 52–70% of the catch, and major (>18%) contributions were made by either Galaxias brevipinnis or Galaxias fasciatus. hi the twelfth river, the Motu

D. K. Rowe; B. A. Saxton; A. G. Stancliff

1992-01-01

53

Infection patterns of Tylodelphys barilochensis and T. crubensis (Trematoda: Diplostomatidae) metacercariae in Galaxias maculatus (Osmeriformes: Galaxiidae) from two Patagonian lakes and observations on their geographical distribution in the southern Andean region, Argentina.  

PubMed

In the Patagonian Andean region, 2 species of diplostomatids parasitize the brains of Galaxias maculatus. The purpose of this study was to evaluate seasonal variation, spatial variation, and association with host age in the transmission of Tylodelphys barilochensis and T. crubensis in several oligotrophic lakes in Argentinian Patagonia. Fishes were captured monthly in Lake Gutiérrez and bimonthly in Lake Escondido. One summer or autumn sample was also taken in several other Patagonian lakes. Infection parameters were calculated and compared using nonparametric tests. The 2 species co-occurred in most of the sampled lakes, with high values of prevalence and mean intensity. In Lake Gutiérrez and Lake Escondido, the intensity of both diplostomatid species did not show significant differences between sexes and co-varied with host length. All age classes were infected; maximum prevalence values were reached before maximum mean intensity values in the 1-yr age class. A seasonal pattern of prevalence and mean intensity of the 2 parasite species with autumn mean intensity values differing significantly from those of the other seasons was evident only in Lake Gutiérrez. PMID:12537107

Flores, Verónica; Liliana, Semenas

2002-12-01

54

Cytotaxonomy of seven species of Galaxias (Pisces: Galaxiidae) in Tasmania  

Microsoft Academic Search

Karyotypes of 7 species of the genus Galaxias in Tasmania are compared and a phylogenetic interpretation of these data offered. Species fall into 3 distinct groups, viz. those with 2n=44 (G. brevipinnis, G. johnstoni and G. fontanus), those with 2n=32 (G. truttaceus, G. tanycephalus and G. auratus), and G. maculatus with 2n=22. Land-locking appears to have been a major evolutionary

C. R. Johnson; R. W. G. White; Y. A. E. Bick

1981-01-01

55

Dispersión de velocidades en cúmulos de galaxias  

NASA Astrophysics Data System (ADS)

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

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

56

Life history of Galaxias divergens (Salmonoidea: Galaxiidae)  

Microsoft Academic Search

Galaxias divergent Stokell is a small, bottom?dwelling fish inhabiting streams in the North Island and the northern part of the South Island. Its ecology is similar in many respects to that of G. vulgaris. The fry develop in the same environment as the adults, unlike the sea?going young of several other Galaxias spec'es. Spawning occurs in spring and summer, and

C. L. Hopkins

1971-01-01

57

Estudio de la galaxia peculiar NGC 1487  

NASA Astrophysics Data System (ADS)

La galaxia peculiar NGC 1487, cuya morfología sugiere un evento de ``merging" o interacción próxima, es estudiada en base a material observacional espectroscópico y fotométrico obtenido en el CASLEO. Mediante técnicas espectrofotométricas standards se determinan las principales características espectrales, los mecanismos de excitación actuantes, las condiciones físicas y las velocidades radiales de las estructuras conspicuas de la galaxia. Por otra parte, usando imágenes directas en las bandas B, V, R e I, se obtienen distribuciones detalladas de los colores B-V, V-R y R-I y detalles de su morfología.

Agüero, E. L.; Paolantonio, S.; Gunthardt, G.

58

Spawning of Galaxias fasciatus Gray (Salmoniformes: Galaxiidae)  

Microsoft Academic Search

For the first time Galaxias fasciatus Gray were observed spawning. The spawning sites were among flooded terrestrial vegetation along the margins of a stream during the peak of a flood. Spawning appeared to be a communal event and the fish were vulnerable to eel (Anguilla dieffenbachii) predation at the time. This spawning behaviour may have some effect on the survival

C. P. Mitchell; B. P. Penlington

1982-01-01

59

Reproduction in Galaxias fasciatus Gray (Salmoniformes : Galaxiidae)  

Microsoft Academic Search

A study of the reproductive cycle was made on Galaxias fasciatus Gray from streams on Banks Peninsula, South Island, New Zealand. There was no spawning migration; adults remained in the usual adult habitat to breed. The course of gonad maturation showed that spawning occurred in the autumn, from the end of April to mid?June. Most males matured at 2 years

C. L. Hopkins

1979-01-01

60

Barred Galaxias (Galaxias fuscus Mack, 1936). R.K. JOURNAL OF THE AUSTRALIA NEW GUINEA FISHES ASSOCIATIONincorporated Registration No. ACO27788J  

E-print Network

Barred Galaxias (Galaxias fuscus Mack, 1936). R.K. JOURNAL OF THE AUSTRALIA NEW GUINEA FISHES H Kuiter MOUNTAIN GALAXIAS ­ Tarmo Raadik Chilatherina axelrodi ­ Barry Crockford SACRED LOTUS ­ Nick Romanowski THE SPOTTED RAINBOW ­ Glenn Briggs 781 #12;785 ... When is a Mountain Galaxias

Canberra, University of

61

Diets of alpine galaxias (Galaxias paucispondylus Stokell) and longjawed galaxias (G. prognathus Stokell) in a South Island, New Zealand, high?country stream  

Microsoft Academic Search

Thedietsofthealpinegalaxias(Galaxias paucispondylus Stokell, 1938) and the longjawed galaxias (G. prognathus Stokell, 1940) were studied in Deep Creek, a high?country stream in the central South Island of New Zealand. Both species are small, slender fish with entirely freshwater life cycles. Their diets were very similar and consisted of aquatic invertebrates, dominated by the larvae of Deleatidium spp. (Ephemeroptera), Hydrobiosis spp. (Trichoptera),

M. L. Bonnett; P. M. Sagar; C. R. Docherty

1989-01-01

62

Possible competitive exclusion of common river galaxias (Galaxias vulgaris) by koaro (G. brevipinnis) following impoundment of the Waipori River, Otago, New Zealand  

Microsoft Academic Search

Common river galaxias (Galaxias vulgaris) are apparently absent from the Waipori River above Lake Mahinerangi, but widespread elsewhere in the Taieri River system including tributaries just below the dam. Koaro (G. brevipinnis) abound in tributaries of Lake Mahinerangi, but are rare in the Taieri River. We hypothesise that koaro have replaced common river galaxias in streams above the Mahinerangi Dam

R. M. McDowall; R. M. Allibone

1994-01-01

63

Terrestrial and benthic foods in the diet of the shortjawed kokopu, Galaxias postvectis Clarke (Teleostei: Galaxiidae)  

Microsoft Academic Search

Shortjawed kokopu from diverse localities feed extensively on several species of cased caddisflies from the stream benthos and on diverse terrestrial invertebrates from the surface. Small caddisflies often dominate the diet numerically and are selected for, whereas other often abundant benthic insects, such as Chironomidae and the mayfly Deleatidium, are avoided. We hypothesise that this selectivity indicates that caddisflies are

R. M. McDowall; M. R. Main; D. W. West; G. L. Lyon

1996-01-01

64

Indigenous vegetation type and the distribution of shortjawed kokopu, Galaxias postvectis (Teleostei: Galaxiidae), in New Zealand  

Microsoft Academic Search

The shortjawed kokopu is found almost exclusively in forested catchments throughout New Zealand. Forest composition appears to be important: the species is found particularly in podocarp\\/hard?wood forests, quite often in podocarp\\/hardwood\\/ beech associations, but only very rarely in pure beech forest. Sites where shortjawed kokopu are more abundant are always in podocarp\\/hardwood forest streams. Analysis of distribution in two representative

R. M. McDowall

1997-01-01

65

Movimientos peculiares de galaxias en el Universo cercano  

NASA Astrophysics Data System (ADS)

Se presenta un resumen de los resultados más importantes obtenidos en los últimos años sobre movimientos peculiares en el Universo Cercano. En el escenario de inestabilidad gravitacional, el campo de velocidades peculiares es una herramienta muy útil para estimar las fluctuaciones en la distribución de masa que generan los movimientos observados. Esta aproximación puede, además, ser utilizada para poner restricciones al espectro de potencia de la masa, a la relación entre las distribuciones de galaxias y de materia y al valor del parámetro de densidad cosmológico, ?, a grandes escalas. Son además presentados una reconstrucción preliminar de los campos de densidad de masa y velocidades peculiares en el universo cercano usando nuevas medidas de distancias obtenidas con la relación Dn - ?, para una muestra de galaxias elípticas y lenticulares. Dos subestructuras prominentes son encontradas en la región del Gran Atractor, que corresponden a los complejos de Centaurus y Pavo--Indus. Estos últimos, junto a los complejos de Perseus--Piscis y Cetus parecen ser importantes estructuras que determinan el flujo global. El patrón obtenido a través de una muestra de galaxias elípticas muestra variaciones con respecto al obtenido por galaxias espirales. Estos nuevos resultados muestran una coherencia menor en el flujo global, cuando son comparados con resultados obtenidos anteriormente.

Alonso, M. V.

66

Age?related growth characteristics of Galaxias fasciatus (Salmoniformes: Galaxiidae)  

Microsoft Academic Search

Galaxias fasciatus Gray is one of the diadromous galaxiids whose juveniles are known in New Zealand as whitebait. Its otoliths are shown to have a regular pattern of summer and winter zones that can be used for age determination. Age and annual growth were examined in specimens from the South Island and from the Owhiro Stream, Wellington. A form of

C. L. Hopkins

1979-01-01

67

Downstream movement of fry of galaxias fasciatus gray (note)  

Microsoft Academic Search

The fry of Galaxias fasciatus Gray were recorded for the first time, being carried downstream on a flood. Attempts to rear the fry in tanks in fresh and in salt water were unsuccessful, but those kept in salt water began to feed and survived for several weeks.

G. A. Eldon

1975-01-01

68

Morphological variation in diadromous and landlocked populations of the spotted galaxias, Galaxias truttaceus , in Tasmania, south-eastern Australia  

Microsoft Academic Search

A comparison of a suite of morphometric measurements and meristic counts of individuals of two landlocked lacustrine and two diadromous riverine populations of Galaxias truttaceus was carried out utilising both univariate and canonical variate analyses. Lacustrine fish had fewer dorsal and anal fin rays than did riverine fish. Differences were not as clear for gill rakers and vertebrae. Comparisons of

Paul Humphries

1990-01-01

69

The Canterbury mudfish, Galaxias burrowsius Phillipps, a vanishing species  

Microsoft Academic Search

Examination of available samples and of ecological knowledge of Galaxias burrowsius Phillipps (Galaxiidae) suggests that this species is confined to the Canterbury Plains and is now nearly extinct.Possible reasons for its decline are analysed and it is suggested that this decline may have started nearly 1,000 years ago with the changes in the climate?vegetation pattern. It has been hastened by

W. Skrzynski

1968-01-01

70

Size?related impacts of introduced brown trout on the distribution of native common river galaxias  

Microsoft Academic Search

The impact of small (fork length < 100 mm) and large (? 100 mm) brown trout (Salmo trutta L.) on the distribution of the common river galaxias (Galaxias vulgaris Stokell) was investigated in the Shag River (South Island, New Zealand). Riffle reaches were sampled by electrofishing and their macrohabitat was described in terms of substratum, flow, elevation, and vegetation characteristics.

Angus R. McIntosh; Todd A. Crowl; Colin R. Townsend

1994-01-01

71

Comparison of Day and Night Fyke Netting, Electrofishing and Snorkelling for Monitoring a Population of the Threatened Golden Galaxias ( Galaxias auratus )  

Microsoft Academic Search

The littoral zone of small off-stream water storage containing a translocated population of Galaxias auratus was sampled fortnightly at day and night with fyke nets, electrofishing and snorkelling over 3 months. Variation in population\\u000a data provided by each method, including relative abundance indices, size structure, and habitat preferences, were examined.\\u000a Aspects of behaviour and activity patterns were also investigated. Night sampling

Scott A. Hardie; Leon A. Barmuta; Robert W. G. White

2006-01-01

72

Prey selection by Galaxias vulgaris in the Hawkins River, New Zealand  

Microsoft Academic Search

To determine the extent of prey selection by the nocturnally active fish Galaxias vulgaris, samples of fish, drift, and benthos were collected over a 24?h period in summer in a stream draining the foothills of the Southern Alps in New Zealand. Feeding started after sunset, peaked by midnight, and virtually ceased by midday. Both drifting and benthic foods were consumed,

Gordon J. Glova; Paul M. Sagar

1989-01-01

73

Relationship between brain morphology and ecology in New Zealand Galaxiidae, particularly Galaxias vulgaris (Pisces: Salmoniformes)  

Microsoft Academic Search

Size?related changes in the relative proportions of the forebrain, optic lobes, and cerebellum occur in Galaxias vulgaris Stokell. The relative increase in size of the forebrain and reduction in size of the optic lobes are associated with a change from the free?swimming existence of recently hatched fish to the cryptic habits of adults. The relative increase in size of the

P. L. Cadwallader

1975-01-01

74

A new species of Galaxias (Pisces:Galaxiidae) from Chatham Island, New Zealand  

Microsoft Academic Search

A new species of galaxiid fish from a peat lake on Chatham Island is described. This small freshwater fish is sufficiently distinct to have no obvious close relatives from among the other species of Galaxias in New Zealand. It is readily identified by the presence of pronounced caudal flanges and a moderately forked caudal fin.

C. P. Mitchell

1995-01-01

75

Observations of surface feeding behaviour in pools by koaro, Galaxias brevipinnis  

Microsoft Academic Search

Large koaro (Galaxias brevipinnis) were observed drift?feeding in the water column and from the surface in a pool in Cave Brook, a tributary of Big River draining the Gouland Downs, Kahurangi National Park: an area free of introduced trout. This contrasts with the common perception of koaro habitat being cascades and fast, boulder riffles. It is suggested that sampling limitations

John W. Hayes

1996-01-01

76

Timing and habitat of koaro (Galaxias brevipinnis) spawning in streams draining MtTaranaki, New Zealand  

Microsoft Academic Search

A spawning site of Galaxias brevipinnis Giinther was located in a New Zealand stream for the first time. It was at the edge of a riffle and only partially submerged. The habitat used for spawning matched that described for G. brevipinnis in Australia. Spawning was estimated to have occurred between late April and early May and the eggs hatched in

Richard M. Allibone; Dean Caskey

2000-01-01

77

Notes on some Galaxias fossils from the pliocene of New Zealand  

Microsoft Academic Search

Three fossil Galaxias from diatomaceous shales in Fraser’s Gully, Kaikorai Valley near Dunedin were examined. They are shown to be G. brevipinnis Günther, an extant species, widespread in New Zealand. G. kaikorai Whitley, a name applied to one of the fossils, becomes a junior synonym. Two specimens from similar deposits in the Foulden Hills near Middlemarch are identified as G.

R. M. McDowall

1976-01-01

78

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

USGS Publications Warehouse

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

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

1999-01-01

79

La frontera a alto corrimiento al rojo historia de la formacion de las galaxias  

E-print Network

This review presents a brief discussion of the theory of Cold Dark Matter of structure formation in the universe, describing the main processes determining the power spectrum, the non-linear gravitational collapse, the formation of galaxies and the evolution of the intergalactic medium. Recent advances in the observations of high redshift galaxies, and their interpretation in the context of this theory, are then summarized. Este artí culo de revisión presenta una breve exposición de la teorí a de la Materia Invisible Frí a de la formación de estructura en el universo, describiendo los procesos más importantes que determinan el espectro de potencia, el colapso gravitatorio no lineal, la formación de galaxias y la evolución del medio intergaláctico. Resumimos también los avances recientes en las observaciones de galaxias a alto corrimiento al rojo, y la interpretación en el contexto de esa teorí a.

Miralda-Escudé, J

1999-01-01

80

Sensory deficits induced by cadmium in banded kokopu, Galaxias fasciatus, juveniles  

Microsoft Academic Search

The potential for cadmium to produce sensory deficits in the mechanosensory lateral line and olfactory systems was examined in migratory Galaxias fasciatus juveniles or ‘whitebait’. Using a two-choice chamber apparatus, three groups of whitebait were tested for a known attraction to adult pheromones and then exposed to either 0.1, 0.5 or 1?µg Cd+2 l-1 for 48?h and retested. The attraction

Cindy F. Baker; John C. Montgomery

2001-01-01

81

Why Do Female Callosobruchus maculatus Kick Their Mates?  

PubMed Central

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

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

2014-01-01

82

Evolution of Herbivory in a Carnivorous Clade of Minnows (Teleostei: Cyprinidae): Effects on Gut Size  

E-print Network

000 Evolution of Herbivory in a Carnivorous Clade of Minnows (Teleostei: Cyprinidae): Effects constructed a phylogeny for 10 minnow species (family Cyprinidae) previously revealed to be members of sister

Evans, David H.

83

Southwestern Association of Naturalists Distribution and Status of the Chihuahua Chub (Teleostei: Cyprinidae: Gila nigrescens), with  

E-print Network

: Cyprinidae: Gila nigrescens), with Notes on Its Ecology and Associated Species Author(s): David L. Propst OF THE CHIHUAHUA CHUB (TELEOSTEI: CYPRINIDAE: GILANIGRESCENS), WITH NOTES ON ITS ECOLOGY AND ASSOCIATED SPECIES

84

Insecticidal effect of some spices on Callosobruchus maculatus (Fabricius) in black gram seeds  

Microsoft Academic Search

The experiment was conducted to investigate the insecticidal potency of some spices eg. clove (Syzygium aromaticum), black pepper (Piper nigrum), ceylon cinnamon (Cinnamomum zeylanicum), black cardamom (Amomum subulatum), nutmeg (Myristica fragnans), black cumin (Nigella sativa), turmeric (Curcuma longa), red pepper (Capsicum frutescens), cumin (Cuminum cyminum), green cardamom (Elettaria cardamomum) and bay leaf (Cinnamomum tamala), against the pulse beetle, Callosobruchus maculatus

Shah Hussain Ahmad Mahdi

2008-01-01

85

La frontera a alto corrimiento al rojo: historia de la formacio'n de las galaxias  

E-print Network

This review presents a brief discussion of the theory of Cold Dark Matter of structure formation in the universe, describing the main processes determining the power spectrum, the non-linear gravitational collapse, the formation of galaxies and the evolution of the intergalactic medium. Recent advances in the observations of high redshift galaxies, and their interpretation in the context of this theory, are then summarized. Este art\\'\\i culo de revisi\\'on presenta una breve exposici\\'on de la teor\\'\\i a de la Materia Invisible Fr\\'\\i a de la formaci\\'on de estructura en el universo, describiendo los procesos m\\'as importantes que determinan el espectro de potencia, el colapso gravitatorio no lineal, la formaci\\'on de galaxias y la evoluci\\'on del medio intergal\\'actico. Resumimos tambi\\'en los avances recientes en las observaciones de galaxias a alto corrimiento al rojo, y la interpretaci\\'on en el contexto de esa teor\\'\\i a.

Jordi Miralda-Escude

1999-10-29

86

Effects of inhibitory neurotransmitters on the mudpuppy (Necturus maculatus) locomotor pattern in vitro  

Microsoft Academic Search

Effects of inhibitory neurotransmitters on the locomotor rhythm and pattern generation were investigated using an in vitro\\u000a preparation isolated from the mudpuppy (Necturus maculatus). The preparation consisted of the first five segments of the spinal cord and the right forelimb attached by the brachial\\u000a nerves. During N-methyl-d-aspartate (NMDA)-induced locomotion, the rhythmic motor output (EMG) was recorded unilaterally from elbow flexor

K. Jovanovi?; T. Petrov; R. B. Stein

1999-01-01

87

Repellent and fumigant toxicity of essential oil from Thymus persicus against Tribolium castaneum and Callosobruchus maculatus.  

PubMed

Repellent and insecticidal activity of the essential oil extracted from Thymus persicus (Roniger ex Reach. F.) Jalas was evaluated against two stored-product beetles Tribolium castaneum (Herbst) and Callosobruchus maculatus (F.). Dry flowering aerial parts of the plant were subjected to hydro distillation using a modified Clevenger-type apparatus. The repellent and fumigant toxicity were tested against 1-7 days old adult beetles at 27 +/- 1 degrees C and 65 +/- 5% RH in dark condition. The repellency on C. maculatus and T. castaneum at highest concentration (2 microL/mL acetone) was 82.40% and 70.40% respectively. Fumigation bioassays showed that C. maculatus adults were significantly more susceptible (LC50 = 2.39 microL/L air) to the essential oil than T. castaneum adults (LC50 = 234.42 microL/L air). It could be concluded that T. persicus may have potential for applications in management of stored-product pests because of its safety, strong repellency and fumigant toxicity. PMID:19226805

Moharramipour, S; Taghizadeh, A; Meshkatalsadat, M H; Talebi, A A; Fathipour, Y

2008-01-01

88

New cystidicolid species (Nematoda) from Galaxias platei (Osmeriformes: Galaxiidae) in Patagonian freshwater environments.  

PubMed

During a parasitological survey of Galaxias platei Steindachner, 1898, from Patagonian Andean Lakes, a new species of Cystidicolidae was found in the stomach of fish. The new species was described using light and scanning electron microscopy; the species has characteristics of Ascarophis and is distinguishable from other species by a combination of the following features: well-developed pseudolabia with T-shaped inner extensions, bifurcate deirids, small ratio GE:ME, small left spicule, small ratio LS:RS, and larvigerous eggs with thick and fine filaments in both poles. Intraspecific variation in the morphology of larvigerous eggs was studied. This is the first species of Ascarophis described from freshwater fishes. PMID:18576739

Brugni, Norma L; Viozzi, Gustavo P

2008-08-01

89

Variation in vertebral number and its morphological implication in Galaxias platei.  

PubMed

Variation in the vertebral number of the puyen grande Galaxias platei was examined for specimens from 22 localities that span the entire distribution range of the species (from 40° to 55° S). The mean vertebral number (NMW ) increases towards high latitudes, i.e. Jordan's rule is applicable to this species. Owing to the wide geographic variation of the species, not only in latitude but also in altitude, the most explicative variable for NMW was mean winter air temperature, showing negative dependence. Morphological data suggest that the increment in vertebral number lies in the pre-pelvic region of the trunk and in the caudal region, but not in the segment between pelvic-fin insertion and the origin of the anal fin. As these alterations in body shape have important consequences for hydrodynamics and swimming performance, vertebral number variation in G. platei also holds implications for both individual and population fitness. PMID:24124792

Barriga, J P; Milano, D; Cussac, V E

2013-11-01

90

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

NASA Astrophysics Data System (ADS)

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

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

91

Clasificando galaxias  

NSDL National Science Digital Library

This is a lesson about sorting and classification. In groups, learners will sort twenty images of galaxies into categories of their own devising. Then, the groups compare notes about their sorting criteria and learn more about what the different visual characteristics of galaxies imply. This is Actividad 8.5 as part of El Universo a Sus Pies, a Spanish-language curriculum available for purchase.

92

Mitochondrial and allozyme genetics of two Tasmanian galaxiids (Galaxias auratus and G. tanycephalus, Pisces: Galaxiidae) with restricted lacustrine distributions  

Microsoft Academic Search

Galaxias auratus and G. tanycephalus have a restricted distribution in Tasmanian highland lakes and were probably derived from a landlocked population of the diadromous G. truttaceus during the last 100,000 years. We have analysed the mitochondrial DNA and the allozyme products of 22 nuclear loci for each lake species. Four mitochondrial DNA haplotypes, defined by 40-42 six-base restriction sites, were

J R Ovenden; R W G White; M Adams

1993-01-01

93

Ontogenetic habitat shifts by Galaxias gracilis (Galaxiidae) between the littoral and limnetic zones of Lake Kanono, New Zealand  

Microsoft Academic Search

Diel and spatial differences in distribution were determined for the larvae, juveniles, and adults of Galaxias gracilis (Galaxiidae) in a New Zealand dune lake during summer months. Larvae (mostly 10–25 mm TL) and juveniles (25–40 mm TL) inhabited shallow (0–3 m) waters of the limnetic zone and fed predominantly on two limnetic zooplankton species; Bosmina meridionalis and a calanoid copepod.

David K. Rowe; Ben L. Chisnall

1996-01-01

94

The alternation of different morphotypes in the seasonal cycle of the toxic diatom Pseudo-nitzschia galaxiae  

Microsoft Academic Search

The marine diatom Pseudo-nitzschia galaxiae Lundholm et Moestrup has been recently described from Mexican and Australian plankton. In this paper, we illustrate the considerable morphological variability of the species in the Mediterranean Sea and present first evidence of its toxicity. In addition to lanceolate cells 25–41?m long, which fit the original description of the species, markedly larger (<82?m) and smaller

Federica Cerino; Luisa Orsini; Diana Sarno; Carmela Dell’Aversano; Luciana Tartaglione; Adriana Zingone

2005-01-01

95

Insecticidal activity and chemical composition of the Morinda lucida essential oil against pulse beetle Callosobruchus maculatus.  

PubMed

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

Owolabi, Moses S; Padilla-Camberos, Eduardo; Ogundajo, Akintayo L; Ogunwande, Isiaka A; Flamini, Guido; Yusuff, Olaniyi K; Allen, Kirk; Flores-Fernandez, Karen Isabel; Flores-Fernandez, Jose Miguel

2014-01-01

96

Mitochondrial and allozyme genetics of incipient speciation in a landlocked population of Galaxias truttaceus (Pisces: Galaxiidae).  

PubMed

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

Ovenden, J R; White, R W

1990-03-01

97

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

PubMed Central

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

Ovenden, J. R.; White, RWG.

1990-01-01

98

Megalampris keyesi, a giant moonfish (Teleostei, Lampridiformes) from the Late Oligocene of New Zealand  

Microsoft Academic Search

A new genus and species of fossil moonfish (Teleostei, Lampridiformes, Lamprididae) is reported on the basis of a large, partially articulated skeleton from North Otago, New Zealand. The source horizon is shelf sediments of basal Otekaike Limestone, upper Duntroonian stage, Upper Oligocene (~26 Ma). The deep-bodied proportions of the fossil, along with features of its caudal and pectoral skeleton, support

Michael D. Gottfried; R. Ewan Fordyce; Seabourne Rust

2006-01-01

99

Current insecticide susceptibility status of Malaysian Anopheles maculatus Theobald to malathion, permethrin, DDT and deltamethrin.  

PubMed

Chemical insecticides are still considered as important control agents for malaria vector control. However, prolonged use of these chemicals may select mosquito vectors for resistance. In this study, susceptibility status of adult Anopheles maculatus collected from 9 localities in peninsular Malaysia, viz., Jeli, Temerloh, Pos Banun, Senderut, Jeram Kedah, Segamat, Kota Tinggi, Kluang and Pos Lenjang were determined using the standard WHO bioassay method in which the adult mosquitoes were exposed to standard insecticide impregnated papers malathion, permethrin, DDT and deltamethrin--at pre-determined diagnostic dosage. Deltamethrin was most effective insecticide among the four insecticides tested, with the LT50 of 29.53 min, compared to malathion (31.67 min), DDT (47.76 min) and permethrin (48.01 min). The effect of all insecticides on the laboratory strain was greater (with all insecticides demonstrated LT50 < 1 hour) than the field strains (deltamethrin 32.7, malathion 53.0, permethrin 62.0, DDT 67.4 min). An. maculatus exhibited low degree of resistance to all test insecticides, indicating that these chemical insecticides are still effective in the control of malaria vector. PMID:24862056

Rohani, A; Aziz, I; Zurainee, M N; Rohana, S H; Zamree, I; Lee, H L

2014-03-01

100

Gene structure, purification and characterization of DNA polymerase beta from Xiphophorus maculatus.  

PubMed

Cloning of the Xiphophorus maculatus Polbeta gene and overexpression of the recombinant Polbeta protein has been performed. The organization of the XiphPolbeta introns and exons, including intron-exon boundaries, have been assigned and were found to be similar to that for human Polbeta with identical exon sizes except for exon XII coding for an additional two amino acid residues in Xiphophorus. The cDNA sequence encoding the 337-amino acid X. maculatus DNA polymerase beta (Polbeta) protein was subcloned into the Escherichia coli expression plasmid pET. Induction of transformed E. coli cells resulted in the high-level expression of soluble recombinant Polbeta, which catalyzed DNA synthesis on template-primer substrates. The steady-state Michaelis constants (Km) and catalytic efficiencies (kcat/Km) of the recombinant XiphPolbeta for nucleotide insertion opposite single-nucleotide gap DNA substrates were measured and compared with previously published values for recombinant human Polbeta. Steady-state in vitro Km and kcat/Km values for correct nucleotide insertion by XiphPolbeta and human Polbeta were similar, although the recombinant Xiphophorus protein exhibited 2.5-7-fold higher catalytic efficiencies for dGTP and dCTP insertion versus human Polbeta. In contrast, the recombinant XiphPolbeta displayed significantly lower fidelities than human Polbeta for dNTP insertion opposite a single-nucleotide gap at 37 degrees C. PMID:15533789

Oehlers, Leon P; Heater, Sheila J; Rains, J Douglas; Wells, Melissa C; David, Wendi M; Walter, Ronald B

2004-07-01

101

The sensory basis of olfactory search behavior in banded kokopu ( Galaxias fasciatus).  

PubMed

The sensory basis of olfactory search behavior was investigated in the banded kokopu, Galaxias fasciatus, using a flow tank. In the presence of a 2 cm s(-1) current flow, banded kokopu use both water current and chemical information to locate a food odor source. The superficial neuromasts of the lateral line system mediate the rheotactic component of the odor search. A physical block of one olfactory nostril did not affect the olfactory search strategy employed by banded kokopu in still water or in the presence of a current flow. Thus, there is no evidence that banded kokopu perform a bilateral comparison of the olfactory stimulus during their odor search. Previously, olfaction and gustation have been the only sensory systems shown to directly mediate orientation and movement towards odor sources in fish. The use of hydrodynamic cues by fish in location of an olfactory source has been previously proposed, but without direct experimental identification of the sensory systems employed. This study identifies the contributing roles of both olfactory and hydrodynamic sensory systems to the olfactory search repertoire of fish. PMID:12209343

Baker, Cindy F; Montgomery, John C; Dennis, Todd E

2002-08-01

102

Cloning of cDNAs and expression of putative insecticidal proteins from Albizzia procera active against cowpea bruchid (Callosobruchus maculatus)  

Microsoft Academic Search

Cowpea, Vigna unguiculata (L.) Walp, is an important crop in West Africa and in north-east South America where it is a major source of dietary protein. Upon storage, severe damage to the seeds often occurs due to the infestation by the larvae of the bruchid beetle, Callosobruchus maculatus (F.). As a result, these seeds can no longer be used for

Maria Teresa Dominguez Samson

2000-01-01

103

[In vitro effect of rainbow trout (Oncorhynchus mykiss) serum in Tylodelphys sp. (trematoda, Diplosromatidae) metacercariae].  

PubMed

Here, it has been described that normal fresh sera from rainbow trout (Oncorhynchus mykiss) were able to lyse Tylodelphys sp. metacercariae isolated from Galaxias maculatus (Jenyns, 1842) (Teleostei, Galaxiidae) brain. This effect was time dependent, and progressively increased since 1 h up to 18 h incubation. There were oscillations in the ability of different sera samples to lyse these parasites. Similar values were achieved with other salmonid sera, and also with normal human sera pool. The lytic activity was abolished by heat-inactivated sera, by zymosan treatment and by incubation in the presence of EDTA. However, the mean values obtained in the presence of EGTA-Mg++ did not significantly differ from those found with sera as a source of complement. The results of this study suggested the role of complement alternative pathway on Tylodephys sp. in vitro lysis, under our experimental conditions. PMID:11757418

Olabuenaga, S

2000-01-01

104

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

PubMed Central

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

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

2012-01-01

105

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

PubMed

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

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

2012-12-01

106

Molecular Phylogeny and Biogeography of Percocypris (Cyprinidae, Teleostei)  

PubMed Central

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

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

2013-01-01

107

Reduced abundance of banded kokopu (Galaxias fasciatus) and other native fish in turbid rivers of the North Island of New Zealand  

Microsoft Academic Search

Laboratory experiments demonstrated that migrant juvenile banded kokopu (Galaxias fasciatus Gray) were more sensitive to suspended sediment (SS) than other native fish species. If juvenile migrants avoid waters made turbid by SS and their recruitment to adult habitats up stream is reduced, then adult abundance may decline in turbid rivers. To test this, we compared the abundance of diadromous native

David Rowe; Murray Hicks; Jody Richardson

2000-01-01

108

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

Microsoft Academic Search

We employed DNA sequence variation at two mitochondrial (control region, COI) regions from 212 individuals of Galaxias platei (Pisces, Galaxiidae) collected throughout Patagonia (25 lakes\\/rivers) to examine how Andean orogeny and the climatic cycles throughout the Quaternary affected the genetic diversity and phylogeography of this species. Phylogenetic analyses revealed four deep genealogical lineages which likely represent the initial division of

TYLER S. ZEMLAK; EVELYN M. HABIT; SANDRA J. WALDE; MIGUEL A. BATTINI; EMILY D. M. ADAMS; DANIEL E. RUZZANTE

2008-01-01

109

Prey capture and accommodation in the sandlance, Limnichthyes fasciatus (Creediidae; Teleostei)  

Microsoft Academic Search

The eyes of the sandlance, Limnichthyes fasciatus (Creediidae, Teleostei) move independently and possess a refractive cornea, a convexiclivate fovea and a non-spherical lens\\u000a giving rise to a wide separation of the nodal point from the axis of rotation of the eye much like that of a chameleon. To\\u000a investigate this apparent convergence of the visual optics in these phylogenetically disparate

J. D. Pettigrew; S. P. Collin; K. Fritsches

2000-01-01

110

IMMUNOCYTOCHEMICAL INVESnGA TIONS OF MUSCLE DIFFERENTIATION IN THE ATLANTIC HERRING (CLUPEA HARENGUS: TELEOSTEI)  

Microsoft Academic Search

The myotomes in yolk-sac larvae of the Atlantic herring (Clupea harengus: Teleostei) contain a single layer of small-diameter superficial muscle fibres surrounding an inner mass of around 280 larger-diameter muscle fibres. The fraction of muscle fibre volume occupied by mitochondria is dependent on temperature, and in larvae reared at 8°C was 41% for the superficial fibres, and 25% for the

I. A. JOHNSTON; Z. HORNE

111

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

PubMed

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

Pinacho-Pinacho, Carlos Daniel; Sereno-Uribe, Ana L; García-Varela, Martín

2014-12-01

112

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

PubMed

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

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

2010-07-01

113

Control of stored grain pest, Callosobruchus maculatus (F.) (Coleoptera: Bruchidae) using the essential oil isolated from Plectranthus zeylanicus.  

PubMed

The bruchid, Callosobruchus maculatus (F.) causes major losses during the storage of cowpea seeds [Vigna unguiculata (L.)Walp.] in Sri Lanka. Essential oil isolated from Plectranthus zeylanicus plant was tested for potential insecticidal activity against C. maculatus. The gas chromatography studies of the essential oil of P. zeylanicus showed that ?-cymene (3.5%), ?-caryophyllene (0.2%), geranyl acetate (9.3%) and geraniol (7.2%) were the major constituents. The adults of C. maculatus were susceptible to both fumigant and contact toxicity of P. zeylanicus plant oil. LC(50) values of 0.927 and 0.010?g?L(-1) were obtained for fumigant toxicity and contact toxicity assays, respectively. Oviposition and F(1) adult emergence were significantly inhibited by P. zeylanicus plant oil at a concentration higher than 0.001?g?L(-1) in both fumigant and contact toxicities. The analysis of olfactometer and choice camber bioassays revealed the repellent effects of the oil of P. zeylanicus plant. PMID:22188569

Balachandra, B A H E; Pathirathna, P U; Paranagama, P A

2012-01-01

114

Transcriptome Analysis of Female and Male Xiphophorus maculatus Jp 163 A  

PubMed Central

Background Xiphophorus models are important for melanoma, sex determination and differentiation, ovoviviparity and evolution. To gain a global view of the molecular mechanism(s) whereby gene expression may influence sexual dimorphism in Xiphophorus and to develop a database for future studies, we performed a large-scale transcriptome study. Methodology/Principal Findings The 454-FLX massively parallel DNA sequencing platform was employed to obtain 742,771 and 721,543 reads from 2 normalized cDNA libraries generated from whole adult female and male X. maculatus Jp 163 A, respectively. The reads assembled into 45,538 contigs (here, a "contig" is a set of contiguous sequences), of which, 11,918 shared homology to existing protein sequences. These numbers estimate that the contigs may cover 53% of the total number of Xiphophorus transcriptome. Putative translations were obtained for 11,918 cDNA contigs, of which, 3,049 amino acid sequences contain Pfam domains and 11,064 contigs encode secretory proteins. A total of 3,898 contigs were associated with 2,781 InterPro (IPR) entries and 5,411 contigs with 132 KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways. There were 10,446 contigs annotated with 69,778 gene ontology (GO) terms and the three corresponding organizing principles. Fifty-four potential sex differentially expressed genes have been identified from these contigs. Eight and nine of these contigs were confirmed by real-time PCR as female and male predominantly expressed genes respectively. Based on annotation results, 34 contigs were predicted to be differentially expressed in male and female and 17 of them were also confirmed by real-time PCR. Conclusions/Significance This is the first report of an annotated overview of the transcriptome of X. maculatus and identification of sex differentially expressed genes. These data will be of interest to researchers using the Xiphophorus model. This work also provides an archive for future studies in molecular mechanisms of sexual dimorphism and evolution, and can be used in comparative studies of other fish. PMID:21483681

Zhang, Ziping; Wang, Yilei; Wang, Shuhong; Liu, Jingtao; Warren, Wesley; Mitreva, Makedonka; Walter, Ronald B.

2011-01-01

115

A new species of Unilatus (Platyhelminthes: Monogenoidea) from the gills of Leporacanthicus galaxias Isbrücker et Nijssen (Siluriformes: Loricariidae) from Brazil.  

PubMed

Unilatus irae sp. nov. (Dactylogyridae) is described from the gills of the armored catfish, Leporacanthicus galaxias Isbrücker et Nijssen (Loricariidae: Ancistrinae), from Guamá river, Pará State, Brazil. The new species can be differentiated from its cogeneners by the combination of the following features: anterior anchor with well-developed superficial root, inconspicuous deep root, shaft bent at midpoint, forming angle of approximately 60°, evenly short curved point; posterior anchor with inconspicuous roots, sclerotized cap of base with small protuberance for articulation to posterior bar; evenly curved shaft and short point; anterior bar broadly V-shaped, with small posteromedial projection; and posterior bar anteriorly expanded on it midportion, with expanded ends slightly curved in posterior direction. PMID:24570054

Branches, Bárbara; Domingues, Marcus V

2014-03-01

116

The Toxicity of a Lipid Transfer Protein (Cc-LTP1) from Coffea canephora Seeds on the Larval Development of Callosobruchus maculatus (Coleoptera: Bruchidae).  

PubMed

In this work, we analyzed the effects of coffee seed proteins, especially Cc-LTP1 on the larval development of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae), a bruchid pest of beans and the most important insect pest of Vigna unguiculata (L.) Walp. Artificial seed assay, which incorporated the F/0-90 fraction from Coffea canephora seeds, resulted in the reduction of oviposition and caused an inhibition of C. maculatus larval development in a dose-dependent manner. The F/0-90 fraction used at a 4 % concentration resulted in the survival of no larvae. The purified Cc-LTP1, at a concentration of 0.5 %, also demonstrated effective inhibition of larval development, reducing both females oviposition and the weight and number of larvae. Cc-LTP1 was also able to inhibit the C. maculatus gut ?-amylase activity, and immunolabeling by an anti-LTP serum was observed in the midgut tissues of the C. maculatus larvae. Cc-LTP1 has shown binding affinity towards microvillar cells, endoplasmic reticulum and mitochondria, as demonstrated by micrographic images taken by a transmission electron microscope. The results from this study indicate that Cc-LTP1 has insecticidal actions toward C. maculatus and exerts anti-nutritional effects with direct actions on intestinal tissues. PMID:25097041

Zottich, Umberto; Da Cunha, Maura; Dias, Germana B; Rabelo, Guilherme R; Oliveira, Antonia Elenir A; Carvalho, André O; Fernandes, Kátia Valevski S; do Nascimento, Viviane V; Gomes, Valdirene M

2014-10-01

117

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

PubMed

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

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

2013-01-01

118

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

PubMed Central

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

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

2013-01-01

119

Effects of cholinergic and noradrenergic agents on locomotion in the mudpuppy (Necturus maculatus).  

PubMed

Some neurotransmitters act consistently on the central pattern generator (CPG) for locomotion in a wide range of vertebrates. In contrast, acetylcholine (ACh) and noradrenaline (NA) have various effects on locomotion in different preparations. The roles of ACh and NA have not been studied in amphibian walking, so we examined their effects in an isolated spinal cord preparation of the mudpuppy ( Necturus maculatus). This preparation contains a CPG that produces locomotor activity when N-methyl- D-aspartic acid (NMDA), an excitatory amino acid agonist, is added to the bath. The addition of carbachol, a long acting ACh agonist, to the bath disrupted the walking rhythm induced by NMDA, while not changing the level of activity in flexor and extensor motoneurons. Adding clonidine, an alpha(2)-noradrenergic agonist, had no effect on the NMDA-induced walking rhythm. Physostigmine, an ACh-esterase inhibitor, disrupted the walking rhythm, presumably by potentiating the effects of endogenously released ACh. Atropine, an ACh antagonist that binds to muscarinic ACh receptors, blocked the effects of carbachol, indicating that the action is mediated, at least in part, by muscarinic receptors. In the absence of carbachol, atropine had no effect. Locomotion was not induced by carbachol, atropine or clonidine in a resting spinal cord preparation. Cholinergic actions do not seem to be essential to the CPG for walking in the mudpuppy, but ACh may convert a rhythmic walking state to a more tonic state with occasional bursts of EMG activity for postural adjustments. PMID:12172661

Fok, M; Stein, R B

2002-08-01

120

Oogenesis and lipids in gonad and liver of daubed shanny (Leptoclinus maculatus) females from Svalbard waters.  

PubMed

Oocyte and liver histomorphology of the daubed shanny (Leptoclinus maculatus) from Isfjorden and Kongsfjorden in Svalbard were investigated during three Arctic seasons: summer (July), autumn (October) and winter (April). Three oocyte developmental phases were observed: primary growth phase, secondary growth phase and maturation phase. We observed four different developmental stages: (1) perinucleolus stage with cortical alveolus formation, (2) lipid droplets formation, (3) vitellogenesis stage and (4) maturation. Late maturation stage of oocytes in the ovaries was from the autumn season. Females accumulated lipids in liver (up to 35.2 % dw) and deposited large amounts of lipids into gonads (up to 52.2 % dw) during maturation. Lipid classes in female gonads changed seasonally, with relative increase in cholesterol during summer and depletion of storage lipids (triacylglycerols and wax esters/cholesterol esters) during the winter. Lipid composition in liver changed during oocyte development and spawning, as neutral lipids were transferred to developing oocytes during summer to autumn. During winter, storage lipids were depleted during starvation. Based on the increase in gonadosomatic index (GSI) with length and observed maturation stages, females seem to mature at a length of about 125-130 mm. The GSI and hepatosomatic index of large females sampled in autumn (September-October) were significantly higher than for females in late winter (April) and spring (May). These results indicate that spawning takes place during winter in Isfjorden and that energy reserves stored in the liver are utilized by females during gonadal development and reproduction. PMID:22437369

Murzina, Svetlana A; Meyer Ottesen, Camilla A; Falk-Petersen, Stig; Hop, Haakon; Nemova, Nina N; Poluektova, Oksana G

2012-10-01

121

Intron-loss evolution of hatching enzyme genes in Teleostei  

PubMed Central

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

2010-01-01

122

Characterization of eight microsatellite markers in the white sea bream, Diplodus sargus (Teleostei, Sparidae).  

PubMed

The white sea bream, Diplodus sargus (Teleostei, Sparidae), is a species with a high commercial importance in Mediterranean aquaculture. There is currently little information available about the genetic characteristics of cultured populations. In this survey, we have developed eight polymorphic microsatellites for the white sea bream using an enriched genome library protocol. All of them were polymorphic in the 67 individuals tested, 32 of which were wild specimens, and 35 were individuals from a captive F(1) broodstock. These markers can potentially be useful tools for use in population genetic studies. PMID:21586024

Pérez, L; Infante, C; Ponce, M; Crespo, A; Zuasti, E; Funes, V; Catanese, G; Manchado, M

2008-11-01

123

Chemical Composition and Insecticidal Activity of Essential Oil from Coriandrum sativum Seeds against Tribolium confusum and Callosobruchus maculatus.  

PubMed

The biological activity of essential oil extracted from coriander, Coriandrum sativum L. (Apiaceae), seeds against adults of Tribolium confusum Duval (Coleoptera: Tenebrionidae) and Callosobruchus maculatus F. (Coleoptera: Bruchidae) was investigated in a series of laboratory experiments. Fumigant toxicity was assessed at 27 ± 1°C and 65 ± 5% R.H., in dark condition. Dry seeds of the plant were subject to hydrodistillation using a Clevenger-type apparatus. The composition of essential oil was analyzed by gas chromatography mass spectrometry. The predominant components in the oil were linalool (57.57%) and geranyl acetate (15.09%). The mortality of 1-7-day-old adults of the insect pests increased with concentration from 43 to 357??L/L air and with exposure time from 3 to 24?h. In the probit analysis, LC(50) values (lethal concentration for 50% mortality) showed that C. maculatus (LC(50) = 1.34??L/L air) was more susceptible than T. confusum (LC(50) = 318.02??L/L air) to seed essential oil of this plant. The essential oil of C. sativum can play an important role in stored grain protection and reduce the risks associated with the use of synthetic insecticides. PMID:23227365

Khani, Abbas; Rahdari, Tahere

2012-01-01

124

Effect of some pulverised plant materials on the developmental stages of fish beetle, Dermestes maculatus Degeer in smoked catfish ( Clarias gariepinus) during storage  

Microsoft Academic Search

The effectiveness of pulverised plant materials; Tithonium diversifolia, Afromomum melegueta, Nicotiana tabacum, Monodora myristica and Piper guineense as ovicidal, larvicidal and adult deterents of fish beetle (Dermestes maculatus) in smoked catfish (Clarias gariepinus) during storage were evaluated. Leaves of T. diversifolia, N. tabacum and seeds of A. melegueta, M. myristica and P. guineese were dried and pulverised into powder. Adults

E. A Fasakin; B. A Aberejo

2002-01-01

125

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

PubMed

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

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

2010-01-01

126

Ultrastructure and potential role of integumentary glandular cells in adult male and female Callosobruchus subinnotatus (Pic) and C. maculatus (Fabricius) (Coleoptera : Bruchidae)  

Microsoft Academic Search

Transmission and scanning electron microscopy methods were used to study the ultrastructure of integumentary glandular cells that may be involved in the production of sex pheromones and other semiochemicals in Callosobruchus subinnotatus and C. maculatus (Coleoptera : Bruchidae). Additionally, we measured electroantennogram (EAG) responses of male and female antennae to solvent extracts and glassadsorbed volatiles from both sexes of C.

Sonny B. Ramaswamy; Shengqiang Shu; William A. Monroe; George N. Mbata

1995-01-01

127

Galaxitaenia toloi n. gen., n. sp. (Eucestoda: Pseudophyllidea) from Galaxias platei (Pisces: Osmeriformes, Galaxiidae), in the Patagonian region of Argentina.  

PubMed

Galaxitaenia n. gen. (Eucestoda: Pseudophyllidea) is proposed to accommodate Galaxitaenia toloi n. gen., n. sp. from Galaxias platei, a freshwater fish inhabiting Andean lakes in Argentine Patagonia. Galaxitaenia belongs to the Triaenophoridae because it possesses a marginal genital pore, a ventral uterine pore, and a follicular vitelline gland. The new genus can be distinguished from other triaenophorids by the following combination of characters: a scolex with a prominent rectangular apical disc without hooks, grooves, or indentations; neck present; segments wider than long to quadrangular; testes in 2 lateral fields, often connected anteriorly; cirrus unarmed; an ovary situated posteriorly; a vagina posterior to the cirrus sac; vitelline follicles medullary, in 2 ventral fields forming 2 wings interrupted medially; a uterus saccate to branched; and eggs without operculum. The types, distribution, and density of microtriches were analyzed on the surface of the tegument of scolex, neck, and immature segments. The presence of tumuli were observed on the apical disc of the scolex. Galaxitaenia toloi n. sp. is the first triaenophorid species recorded in a South American freshwater fish and the fourth helminth parasitizing the intestine of G. platei. PMID:17089762

Gil de Pertierra, Alicia A; Semenas, Liliana G

2005-08-01

128

Aplicando modelos de granos de polvo con propiedades meteoriticas al continuo ionizante de algunos Nucleos Activos de Galaxias  

E-print Network

We construct extinction curves based on Mie's theory for spherical dust grain with size distributions between 50-2500 A and composed by elements found in meteorites. We explore the issue of whether the observed spectral energy distribution might be dust absorbed in the far and near-UV by this kind of dust grains. Using this approach, satisfactory fits to the 11 spectra can be obtained. ----- En este trabajo, presentamos las diversas curvas de extincion que hemos calculado con base a la teoria Mie para granos de polvo esfericos, con distribuciones de acuerdo a su tamano (entre 50-2500 A) y con diversos compuestos quimicos hallados en meteoritos. Bajo el posible paradigma que hemos desarrollado, estas curvas de extincion al ser aplicadas a un continuo ionizante teorico y comparadas con 11 espectros observados de quasares, hemos encontrado de manera exitosa reproducir tanto el quiebre UV asi como el problema de suavidad presentes en el continuo ionizante de algunos Nucleos Activos de Galaxias.

Haro-Corzo, Sinhue Amos Refugio

2008-01-01

129

Aplicando modelos de granos de polvo con propiedades meteoriticas al continuo ionizante de algunos Nucleos Activos de Galaxias  

E-print Network

We construct extinction curves based on Mie's theory for spherical dust grain with size distributions between 50-2500 A and composed by elements found in meteorites. We explore the issue of whether the observed spectral energy distribution might be dust absorbed in the far and near-UV by this kind of dust grains. Using this approach, satisfactory fits to the 11 spectra can be obtained. ----- En este trabajo, presentamos las diversas curvas de extincion que hemos calculado con base a la teoria Mie para granos de polvo esfericos, con distribuciones de acuerdo a su tamano (entre 50-2500 A) y con diversos compuestos quimicos hallados en meteoritos. Bajo el posible paradigma que hemos desarrollado, estas curvas de extincion al ser aplicadas a un continuo ionizante teorico y comparadas con 11 espectros observados de quasares, hemos encontrado de manera exitosa reproducir tanto el quiebre UV asi como el problema de suavidad presentes en el continuo ionizante de algunos Nucleos Activos de Galaxias.

Sinhue Amos Refugio Haro-Corzo; Luc Binette

2008-02-20

130

Nigeria Stored Products Research Institute P.M.B 12543 Lagos, NIGERIA Chenopodium ambroisoides (CHENOPODIACEAE) AS A GRAIN PROTECTANT FOR THE CONTROL OF THE COWPEA PEST Callosobruchus maculatus (COLEOPTERA BRUCHIDAE)  

Microsoft Academic Search

Chenopodium ambroisoides (Chenopodiaceae) was investigated for its insecticidal and ovipositional activity against Callosobruchus maculatus (Coleoptera). Ethanol extract of the plant was applied to a day-old eggs and topically, on adult C. maculatus. Adults that emerged from treated eggs and treated F1 adults decreased significantly in number when compared with the control. Application of C. ambroisoides (5.0% extract) caused 54% mortality

Kehinde A. Kemabonta; Francis Okogbue

131

Extreme positive selection on a new highly-expressed larval glycoprotein (LGP) gene in Galaxias fishes (Osmeriformes: Galaxiidae).  

PubMed

We describe the intron-exon structure and DNA/protein sequences of a new larval glycoprotein (LGP) gene from nine species of galaxiid fish. The gene has a distant similarity to Danio THP (Tamm-Horsfall urinary glycoprotein; uromodulin) and cichlid SPP120 (seminal plasma glycoprotein) due to conserved features of its zona pellucida (ZP) domain, including eight highly conserved cysteines and a consensus furin cleavage site. Using a combination of 454 sequencing of cDNA and exon-primed intron-spanning sequencing of genomic DNA, we obtained full sequences of the coding region (996 bp) and its intervening sequences (1,459 bp). LGP shows an exceptionally strong signal of positive selection over the entire coding region, as evidenced by d(N)/d(S) values >1. Across nine species of Galaxias, 87/332 (26%) amino acid residues are variable, compared with 9/386 (2%) for mitochondrial cytochrome b (cytb) in the same group of species. Across 36 interspecific pairwise comparisons, genetic distances are in all cases larger for coding region than for introns, by a factor of 2.4-fold on average. Reading frame, gene structure, splice sites, and many ZP motifs are conserved across all species. Together with the fact that the gene is expressed in all species, these results argue clearly against the possibility of a pseudogene. We show by 454 sequencing and quantitative polymerase chain reaction that the transcript is abundant (ca. 0.5%) in newly hatched larvae and appears to be almost absent from a range of adult tissues. We postulate that the strong Darwinian evolution exhibited by this protein may reflect some type of immunoprotection at this vulnerable larval stage. PMID:20696791

Wallis, Lise J; Wallis, Graham P

2011-01-01

132

Invasive salmonids and lake order interact in the decline of puye grande Galaxias platei in western Patagonia lakes.  

PubMed

Salmonid fishes, native to the northern hemisphere, have become naturalized in many austral countries and appear linked to the decline of native fishes, particularly galaxiids. However, a lack of baseline information and the potential for confounding anthropogenic stressors have led to uncertainty regarding the association between salmonid invasions and galaxiid declines, especially in lakes, as these have been much less studied than streams. We surveyed 25 lakes in the Aysén region of Chilean Patagonia, including both uninvaded and salmonid-invaded lakes. Abundance indices (AI) of Galaxias platei and salmonids (Salmo trutta and Oncorhynchus mykiss) were calculated using capture-per-unit-effort data from gillnets, minnow traps, and electrofishing. We also measured additional environmental variables, including deforestation, lake morphometrics, altitude, and hydrological position (i.e., lake order). An information-theoretic approach to explaining the AI of G. platei revealed that by far the strongest effect was a negative association with the AI of salmonids. Lake order was also important, and using structural equation modeling, we show that this is an indirect effect naturally constraining the salmonid invasion success in Patagonia. Supporting this conclusion, an analysis of an independent data set from 106 mountain lakes in western Canada showed that introduced salmonids are indeed less successful in low-order lakes. Reproductive failure due to insufficient spawning habitat and harsh environmental conditions could be the cause of these limits to salmonid success. The existence of this effect in Chilean Patagonia suggests that low-order lakes are likely to provide natural ecological refugia for G. platei. Finally, pristine, high-order lakes should be actively protected as these have become rare and irreplaceable unspoiled references of the most diverse, natural lake ecosystems in Patagonia. PMID:22645814

Correa, Cristian; Hendry, Andrew P

2012-04-01

133

Complete mitochondrial genome of the dotted gizzard shad Konosirus punctatus (Teleostei, Clupeidae).  

PubMed

The complete mitochondrial genome of the dotted gizzard shad Konosirus punctatus (Teleostei, Clupeidae) has been determined. The entire sequence is 16,706 bp in length, with a gene content (13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs and 1 control region) and organization similar to that observed in most other vertebrates. Overall base composition of the light strand was represented as 25.8% of A, 29.0% of C, 25.1% of T and 20.1% of G. With the exception of ND6 and eight tRNA genes, all other mitochondrial genes are encoded on the heavy strand. Tandem repeat sequences were observed in the control region, indicating a useful marker for population genetic studies. PMID:22471761

Li, Min; Shi, Sufen; Wang, Ming; Lun, Zhaorong; Yang, Tingbao

2012-08-01

134

Rhombichthys intoccabilis, gen. et sp. nov. (Ellimmichthyiformes, Clupeomorpha, Teleostei), from the Cenomanian (Upper Cretaceous) of Ein Yabrud, Middle East: anatomical description and phylogenetic implications  

Microsoft Academic Search

A new double-armored member of the Ellimmichthyiformes (Clupeomorpha, Teleostei) is described from the Cenomanian (Upper Cretaceous) of Ein Yabrud, near Ramallah, Middle East. The anatomical description of Rhombichthys intoccabilis, gen. et sp. nov., is based on 13 subcomplete or incomplete acid-prepared specimens. This taxon shows several remarkable characters such as an important dorsoventral elongation of the lateral wings of the

Bouziane Khalloufi; René Zaragüeta-Bagils; Hervé Lelièvre

2010-01-01

135

Biomarkers in croakers Micropogonias furnieri (Teleostei: Sciaenidae) from polluted and non-polluted areas from the Patos Lagoon estuary (Southern Brazil): Evidences of genotoxic and immunological effects  

Microsoft Academic Search

Biomarkers of exposure and effect of pollutants were analyzed in croakers Micropogonias furnieri (Teleostei: Sciaenidae) captured in winter and summer in a polluted and in a non-polluted site at the Patos Lagoon estuary (Southern Brazil). Catalase and glutathione S-transferase activities (exposure biomarkers) and lipid peroxidation (effect biomarker) were analyzed in liver samples. Other two effect biomarkers were also studied: blood

Lílian Lund Amado; Carlos Eduardo da Rosa; Alice Meirelles Leite; Loraine Moraes; Wagner Vaz Pires; Grasiela L. Leães Pinho; Camila Martinez Gaspar Martins; Ricardo Berteaux Robaldo; Luis Eduardo Maia Nery; José Maria Monserrat; Adalto Bianchini; Pablo Elias Martinez; Laura Alicia Geracitano

2006-01-01

136

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

PubMed

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

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

2007-01-24

137

Metazoan parasite communities of catfishes (Teleostei: Siluridae) in Benin (West Africa).  

PubMed

The need for more precise information on the effect of dry season on fish parasite communities in Benin lead us to undergo a focus during this season in one of the major sites of collection fry by fish farmers.Metazoan parasites were then inventoried in 166 specimens of catfishes which constituted of C larias gariepinus, Clarias ebriensis, Synodontis schall, Synodontis nigrita, and Chrysichthys nigrodigitatus (Teleostei: Siluridae). Those fishes were collected from fishermen of Agonlin-Lowé at the side of Oueme River in south Benin from November 2011 to March 2012. In total, 12 parasite species were listed comprising three Monogena (Gyrodactylus sp., Synodontella sp., and Protoancylodiscoides chrysichthes), three Cestoda (Stoeksia pujehuni, Lytocestus sp., and Cestode indeterminate), five Nematoda (Paracamallanus cyathopharynx, Procamallanus laevionchus, Cithariniella petterae, Synodontisia thelastomoides, and nematode indeterminate), and one indeterminated Copepod species. Total infestation rate varied between 83.87 and 100 % for the different fish species. This was high but independent of fish sex (? (2)?=?1.669, df?=?4, nonsignificant). The highest mean intensity and mean abundance were, respectively, 44 and 13.33. Monogenea and Nematoda have elevated frequency of dominance, and their presence in the host is significantly correlated (r?=?-0.999; p?

Tossavi, Nounagnon Darius; Gbankoto, Adam; Adité, Alphonse; Ibikounlé, Moudachirou; Grunau, Christoph; Sakiti, Gilbert Nestor

2014-11-01

138

Influence of a Toxic Microcystis aeruginosa Strain on Glutathione Synthesis and Glutathione-S-Transferase Activity in Common Carp Cyprinus carpio (Teleostei: Cyprinidae)  

Microsoft Academic Search

We evaluated the effects of aqueous extracts of the cyanobacterium-producing microcystin (MC), Microcystis aeruginosa (strain RST9501), on detoxification capacity and glutathione (GSH) synthesis in liver, brain, gill, and muscle—as well as\\u000a apoptotic protease (calpain) activity in liver and brain—in the common carp Cyprinus carpio (Teleostei: Cyprinidae). Experimental groups were defined as follows: (1) control (CTR); (2) carp treated with an

Lílian Lund Amado; Márcia Longaray Garcia; Patrícia Baptista Ramos; João Sarkis Yunes; José Maria Monserrat

2011-01-01

139

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

PubMed

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

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

2008-12-01

140

Fine structure of the retina and pigment epithelium in the creek chub, Semotilus atromaculatus (Cyprinidae, Teleostei).  

PubMed

The structure of the light- and dark-adapted retina, the pigment epithelium and the choroid of the creek chub, Semotilus atromaculatus (Cyprinidae, Teleostei) is examined by light and electron microscopy. An extensive network of vitreal blood vessels emanating from the hyaloid artery enters the eye with the optic nerve and overlies the inner limiting membrane. This membrane closely apposes the fine protrusions of the Müller cell processes which traverse the entire retina, dividing the inner retina into alternating fascicles of ganglion cells and optic axons. The inner nuclear layer consists of bipolar, amacrine, Müller cell soma and two layers of horizontal cells. The outer plexiform layer possesses both rod spherules and cone pedicles. Each rod spherule consists of a single synaptic ribbon in either a triad or quadrad junctional arrangement within the invaginating terminal endings of the bipolar and horizontal cell processes. In contrast, cone pedicles possess multiple synaptic ribbons within their junctional complexes and, in the light-adapted state, the horizontal cell processes show spinule formation. Four photoreceptor types are identified on morphological criteria; unequal double cones, large single cones, small single cones and rods. All but the small single cones are capable of retinomotor responses. The rod to cone ratio is approximately 5:1 and the rods form two ill-defined rows in the light-adapted condition. The retinal pigment epithelium possesses two types of osmiophilic granules. These are bound within slender microvilli and migrate vitread to surround the photoreceptors in response to light. Bruch's membrane is trilaminar and the vascularised choroid consists of up to three layers of melanocytes. The endothelial borders of the choroidal blood vessels abutting the outer lamina of Bruch's membrane are fenestrated. PMID:8720447

Collin, S P; Collin, H B; Ali, M A

1996-01-01

141

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

NASA Astrophysics Data System (ADS)

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

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

1993-02-01

142

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

PubMed

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

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

2014-05-01

143

Cytotype-specific ISSR profiles and karyotypes in the Neotropical genus Eigenmannia (Teleostei: Gymnotiformes).  

PubMed

The genus Eigenmannia (Teleostei: Gymnotiformes), a widely distributed fish genus from the Neotropical region, presents very complex morphological patterns and many taxonomic problems. It is suggested that this genus harbors a species complex that is hard to differentiate using only morphological characteristics. As a result, many species of Eigenmannia may be currently gathered under a common name. With the objective of providing new tools for species characterization in this group, an analysis of the polymorphism of DNA inter-simple sequence repeats (ISSR), obtained by single primer amplification reaction (SPAR), combined with karyotype identification, was carried out in specimens sampled from populations of the Upper Paraná, São Francisco and Amazon river basins (Brazil). Specific ISSR patterns generated by primers (AAGC)(4) and (GGAC)(4) were found to characterize the ten cytotypes analyzed, even though the cytotypes 2n = 38 and 2n = 38 XX:XY, from the Upper Paraná basin, share some ISSR amplification patterns. The geographical distribution of all Eigenmannia specimens sampled was inferred, showing the cytotype 2n = 31/2n = 32 as the most frequent and largely distributed in the Upper Paraná basin. The cytotype 2n = 34 was reported for the first time in the genus Eigenmania, restricted to the São Francisco basin. Polymorphic ISSR patterns were also detected for each cytotype. Considering our results and the data reported previously in the literature, it is suggested that many of the forms of Eigenmannia herein analyzed might be regarded as different species. This work reinforces the importance of employing diverse approaches, such as molecular and cytogenetic characterization, to address taxonomic and evolutionary issues. PMID:19779835

Moysés, Cinthia Bachir; Daniel-Silva, Maria de Fatima Zambelli; Lopes, Carlos Eduardo; de Almeida-Toledo, Lurdes Foresti

2010-02-01

144

Henneguya amazonica n.sp. (Myxozoa, Myxobolidae), parasitizing the gills of Crenicichla lepidota Heckel, 1840 (Teleostei, Cichlidae) from Amazon river.  

PubMed

The authors present light and electron microscopical data on a myxosporidian found in the gills of Crenicichla lepidota Heckel, 1840 (Teleostei, Cichlidae) from the Amazon river. Based on the spore morphology, it is concluded that this species belongs to the family Myxobolidae, genus Henneguya, and that it constitutes a new species: Henneguya amazonica n.sp. The fine structure of sporogenesis shows that the development follows, in general, the pattern of this and other genera. Nevertheless, some ultrastructural features are reported for the first time in the genus Henneguya: intercellular bridges between daughter generative cells as well as tubuli arranged in aggregates and dispersed within the capsular matrix. The structure of the trophozoite wall suggests that the species is not highly pathogenic, but, to ascertain the true pathogenicity of the species, further studies are needed. PMID:23195230

Rocha, E; Matos, E; Azevedo, C

1992-08-21

145

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

PubMed

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

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

2014-12-01

146

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

PubMed

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

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

2014-01-01

147

The attraction of virgin female hide beetles (Dermestes maculatus) to cadavers by a combination of decomposition odour and male sex pheromones  

PubMed Central

Introduction The hide beetle Dermestes maculatus (Coleoptera: Dermestidae) feeds as an adult and larva on decomposing animal remains and can also be found on human corpses. Therefore, forensic entomological questions with regard to when and how the first receptive females appear on carcasses are important, as the developmental stages of their larvae can be used to calculate the post-mortem interval. To date, we know that freshly emerged males respond to the cadaver odour of post-bloated carcasses (approximately 9 days after death at Tmean = 27°C), being attracted by benzyl butyrate. This component occurs at its highest concentration at this stage of decay. The aim of our study was to determine the principle of attraction of virgin females to the feeding and breeding substrate. For this purpose, we tested the response of these females to headspace samples of piglet cadavers and male sex pheromones [(Z9)-unsaturated fatty acid isopropyl esters] in a Y-olfactometer. Because we expected that such an odour combination is of importance for virgin female attraction, we tested the following two questions: 1) Are virgin female hide beetles attracted by a combination of cadaver odour and male sex pheromones? 2) During which decomposition stage do the first virgin females respond to cadaver odour when combined with male sex pheromones? Results We found that young virgin females were attracted to the cadaver by a combination of cadaver odour and male sex pheromones. Neither cadaver odour alone nor male sex pheromones alone was significantly more attractive than a solvent control. Our results also gave a weak indication that the first young virgin females respond as early as the post-bloating stage to its associated decomposition odour when combined with male sex pheromones. Conclusions Our results indicate that freshly emerged males possibly respond to cadaver odour and visit carcasses before virgin females. Being attracted to cadavers when male sex pheromone is perceived as well, virgin females can optimise their reproductive possibilities. PMID:22889339

2012-01-01

148

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

USGS Publications Warehouse

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

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

2003-01-01

149

Ultrastructure and organisation of the retina and pigment epithelium in the cutlips minnow, Exoglossum maxillingua (Cyprinidae, Teleostei).  

PubMed

The structure of the light- and dark-adapted retina, pigment epithelium and choriocapillaris of the cutlips minnow, Exoglossum maxillingua (Cyprinidae, Teleostei) is examined by light and electron microscopy. A pronounced vitreal vascularisation overlies the inner retina where the blood vessel walls, the inner limiting membrane and the Müller cell endfeet are all closely apposed. The thick Müller cell processes divide the inner plexiform layer and nerve fibre layer into discrete compartments. The ganglion cells do not form fascicles and lie within both the ganglion cell and inner plexiform layers. The inner nuclear layer consists of amacrine, bipolar, Müller cell somata and two rows of horizontal cells. The photoreceptor terminals comprise either multiple (3-5 in cone pedicles) or single (rod spherules) synaptic ribbons. These photoreceptor terminals form either a triad (rods and cones) or a quadrad (cones) arrangement of contact with the invaginating processes of the inner nuclear layer cells. The horizontal cell processes of the cone photoreceptor terminals reveal spinule formation in the light-adapted condition. Five photoreceptor types are classified using morphological criteria; triple cones, unequal double cones, large single cones, small single cones and rods. The ratio of rods to cones is approximately 7:1. All photoreceptor types show retinomotor responses. Only the cones possess accessory outer segments but both rods (8-11) and cones (15-19) possess calycal processes. The retinal pigment epithelium displays retinomotor responses where pigment granules within fine apical processes move vitread to mask the rods in the light. The cells of the retinal pigment epithelium are joined by various types of junctions and contain numerous phagosomes, mitochondria and polysomes. Bruch's membrane or the complexus basalis is trilaminate with two types of collagen fibrils comprising the central layer. The endothelia of the blood vessels of the choriocapillaris, facing Bruch's membrane, are fenestrated. Two to three layers of melanocytes interspersed between large thin-walled capillaries and several layers of collagen fibrils comprise the choriocapillaris. PMID:8720448

Collin, S P; Collin, H B; Ali, M A

1996-01-01

150

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

PubMed

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

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

2013-02-10

151

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

PubMed

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

Lavoué, Sébastien; Sullivan, John P

2004-10-01

152

Distribución de Masa en Galaxias Espirales  

NASA Astrophysics Data System (ADS)

We study the relationship between Kinematics and Surface Brightness in a sample of 22 spiral galaxies. We pay attention on the uncertainties that are involved in the velocity and brightness interpretation in terms of mass and luminosities. Finally, we analyze how the observational bias could affect the determination of the dark halo potential. FULL TEXT IN SPANISH

Agüero, M. P.; Díaz, R. J.

153

Galaxias enanas: las voces de la mayoría  

NASA Astrophysics Data System (ADS)

More than twenty years after photographic surveys of nearby clusters of galaxies revealed that low-luminosity, or ``dwarf'', galaxies (M_B ? -18 mag) are the numerically dominant population, research on these objects has been boosted by new instrumental and theoretical developments. Among several breakthroughs that have re-shaped our knowledge abut dwarf galaxies, we should point out: the detection of underlying spiral structure, disks/bars in dwarf ``elliptical'' galaxies; the possible evolutionary relation between (some?) dwarf ellipticals and spiral galaxies; the discoveries of ultra-compact and ultra-faint dwarfs; the universality of the color-luminosity relation extending along ˜ 10 mag. A brief review on these subjects is presented, with emphasis on early-type dwarfs and their possible evolutionary relations with other galaxy types. I will particularly address the controversy about which are the objects that extend the E sequence down to the lowest luminosities (if such objects really exist). FULL TEXT IN SPANISH

Cellone, S. A.

154

Las Galaxias Enanas y la Red Cósmica  

NASA Astrophysics Data System (ADS)

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

Benítez Llambay, A.; Abadi, M. G.

155

Descubren el origen de las "galaxias negras"  

E-print Network

A group of researchers from Zurich University think having discovered the origin of the "black galaxies", things not well known, with the size of a galaxy with few or no stars and formed by dark matter, dust and gas. (1/2 page)

2007-01-01

156

Climate-induced changes to the ancestral population size of two Patagonian galaxiids: the influence of glacial cycling.  

PubMed

Patagonia is one of the few areas in the Southern Hemisphere to have been directly influenced by Quaternary glaciers. In this study, we evaluate the influence that Quaternary glacial ice had on the genetic diversity of two congeneric fish species, the diadromous Galaxias maculatus and the nondiadromous Galaxias platei, using multilocus estimates of effective population size through time. Mid-Quaternary glaciations had far-reaching consequences for both species. Galaxias maculatus and G. platei each experienced severe genetic bottlenecks during the period when Patagonia ice sheet advance reached its maximum positions c. 1.1-0.6 Ma. Concordant drops in effective size during this time suggest that range sizes were under similar constraints. It is therefore unlikely that coastal (brackish/marine) environments served as a significant refuge for G. maculatus during glacial periods. An earlier onset of population declines for G. platei suggests that this species was vulnerable to modest glacial advances. Declines in effective sizes were continuous for both species and lasted into the late-Pleistocene. However, G. maculatus exhibited a strong population recovery during the late-Quaternary (c. 400,000 bp). Unusually long and warm interglacials associated with the late-Quaternary may have helped to facilitate a strong population rebound in this primarily coastal species. PMID:22077139

Zemlak, Tyler S; Walde, Sandra J; Habit, Evelyn M; Ruzzante, Daniel E

2011-12-01

157

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

PubMed

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

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

2010-12-01

158

Gyrodactylus salinae n. sp. (Platyhelminthes: Monogenea) infecting the south European toothcarp Aphanius fasciatus (Valenciennes) (Teleostei, Cyprinodontidae) from a hypersaline environment in Italy  

PubMed Central

Background Historically, non-native species of Gambusia (Poeciliidae) have been used to control larval stages of the Asian tiger mosquito, Stegomyia albopicta Reinert, Harbach et Kitching, 2004 throughout Italy. The potential utility of indigenous populations of Aphanius fasciatus (Valenciennes) (Teleostei: Cyprinodontidae) as an appropriate alternative biological control is currently being explored. A sub-sample of ten fish collected from Cervia Saline, Italy (salinity 65 ppt; 30°C) to assess their reproductive capability in captivity, harboured a moderate infection of Gyrodactylus von Nordmann, 1832 (Platyhelminthes, Monogenea). A subsequent morphological and molecular study identified this as being a new species. Results Gyrodactylus salinae n. sp. is described from the skin, fins and gills of A. fasciatus. Light and scanning electron microscopical (SEM) examination of the opisthaptoral armature and their comparison with all other recorded species suggested morphological similarities to Gyrodactylus rugiensoides Huyse et Volckaert, 2002 from Pomatoschistus minutus (Pallas). Features of the ventral bar, however, permit its discrimination from G. rugiensoides. Sequencing of the nuclear ribosomal DNA internal transcribed spacers 1 and 2 and the 5.8S rRNA gene and a comparison with all species listed in GenBank confirmed they are unique and represent a new species (most similar to Gyrodactylus anguillae Ergens, 1960, 8.3% pair-wise distance based on 5.8S+ITS2). This represents the first species of Gyrodactylus to be described from Aphanius and, to date, has the longest ITS1 (774 bp) sequenced from any Gyrodactylus. Additional sampling of Cervia Saline throughout the year, found G. salinae n. sp. to persist in conditions ranging from 35 ppt and 5°C in December to 65 ppt and 30°C in July, while in captivity a low level of infection was present, even in freshwater conditions (0 ppt). Conclusions The ability of G. salinae n. sp. to tolerate a wide range of salinities and temperatures shows its potential to readily adapt to several environmental conditions. These findings, together with the fact that A. fasciatus is a protected species and is considered as a biological control organism, necessitate further studies on the ecology and virulence of G. salinae n. sp. PMID:21658217

2011-01-01

159

Retinal and lenticular ultrastructure in the aestivating salamanderfish, Lepidogalaxias salamandroides (Galaxiidae, Teleostei) with special reference to a new type of photoreceptor mosaic.  

PubMed

The salamanderfish, Lepidogalaxias salamandroides (Galaxiidae, Teleostei) is endemic to southwestern Australia and inhabits shallow, freshwater pools which evaporate during the hot summer months. Burrowing into the substrate in response to falling water levels allows these fish to aestivate for extended periods of time while encapsulated in a mucous cocoon even when the pools contain no water. Only a few minutes after a major rainfall, these fish emerge into relatively clear water which subsequently becomes laden with tannin, turning the water black and reducing the pH to approximately 4.3. As part of a large study of the visual adaptations of this unique species, the retinal and lenticular morphology of the aestivating salamanderfish is examined at the level of the light and electron microscopes. The inner retina is highly vascularised by a complex system of vitreal blood vessels, while the outer retina receives a blood supply by diffusion from a choriocapillaris. This increased retinal blood supply may be an adaptation for reducing the oxygen tension during critical periods of aestivation. Large numbers of Müller cells traverse the thickness of the retina from the inner to the outer limiting membranes. The ganglion cells are arranged in two ill-defined layers, separated from a thick inner nuclear layer containing two layers of horizontal cells by a soma-free inner plexiform layer. The photoreceptors can be divided into three types typical of many early actinopterygian representatives; equal double cones, small single cones and large rods (2:1:1). These photoreceptors are arranged into a unique regular square mosaic comprising a large rod bordered by four equal double cones with a small single cone located at the corner of each repeating unit. The double cones may optimise perception of mobile prey which it tracks by flexion of its head and "neck" and the large rods may increase sensitivity in the dark tannin-rich waters in which it lives. Each single cone also possesses a dense collection of polysomes and glycogen (a paraboloid) beneath its ellipsoid, the first such finding in teleosts. The retinal pigment epithelium possesses melanosomes, phagocytes and a large number of mitochondria. The anatomy of the retina and the photoreceptor mosaic is discussed in relation to the primitive phylogeny of this species and its unique life history. PMID:9810500

Collin, S P; Collin, H B

1998-10-01

160

[Distribution of the infection by Camallanus corderoi (Nemata: Spiruroidea) in different autochthonous hosts and localities of the Valdivia river basin, Chile].  

PubMed

Six hundred and thirty nine autochthonous fish were examined in 1986-1987 in search for Camallanus corderoi infection on different biotopes from Valdivia River basin (between 39 degrees 30'-40 degrees 00'S, 73 degrees 30'-71 degrees 45'' W). Brachigalaxias bullocki, Galaxias maculatus, Galaxias platei, Aplochiton taeniatus, Cheirodon australe, Basilichthys australis and Cauque mauleanum are new hosts for C. corderoi. Infection by C. corderoi in fish is acquired by ingestion of infected copepods and prevalence and intensity of infection showed differences between host fish and biotopes. In general, infrapopulations of C. corderoi showed overdispersion in different hosts. PMID:2152359

Torres, P; Franjola, R; Cabezas, X; Neira, A; Covarrubias, C

1990-01-01

161

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

PubMed

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

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

2002-01-01

162

Variable survival across low pH gradients in freshwater fish species.  

PubMed

A series of 14 day experiments was conducted on five common New Zealand fish species (redfin bully Gobiomorphus huttoni, inanga Galaxias maculatus, brown trout Salmo trutta, longfin eel Anguilla dieffenbachii and koaro Galaxias brevipinnis) to assess the effect of pH on survival and changes in body mass. No species survived in water of pH <4 although there was 100% survival of all adults at pH 4·5, G. maculatus larvae were also tested and had high mortality at this pH. Results suggest that adults are tolerant of low-pH waters; however, successful remediation of anthropogenically acidified streams will require an understanding of the susceptibility to low pH on different life cycle stages. PMID:25230112

Jellyman, P G; Harding, J S

2014-11-01

163

Perfiles de densidad de galaxias 3-D y segregación por tipo espectral en grupos de galaxias  

NASA Astrophysics Data System (ADS)

We have analysed the distribution of galaxies in groups identified in the largest redshift surveys available: the final release of the 2dF Galaxy Our work comprises the study of the galaxy density profiles and the fraction of galaxies per spectral type as a function of the group-centric distance. We have calculated the projected galaxy density profiles of groups using composite samples in order to increase the statistical significance of the results and we infer the 3-D galaxy density profiles using a deprojection method similar to the developed by Allen & Fabian. Special cares have been taken in order to avoid possible biases in the group identification and the construction of the projected galaxy density profile estimator due to the irregular sky coverage of the 2dF Galaxy Redshift Survey. We have adopted a generalized King profile to fit the obtained projected density profiles and use them to construct mock clusters and obtain the 3-D density profiles per spectral type. From the 3-D galaxy density profile we have estimated the 3-D fraction of galaxies per spectral type. Comparing with the fraction of galaxies computed using the projected profiles we observe a similar behavior of the galaxy spectral type segregation as the obtained by Domínguez et al. for groups in the early data release of the 2dF Galaxy Redshift Survey. As expected, the trends obtained for the 3-D galaxy fractions show steeper slopes.

Díaz, E.; Zandivarez, A.; Merchán, M. E.; Muriel, H.

164

Evolución en Núcleos Activos de Galaxias y QSOs I. Relación Starbursts y AGNs en Galaxias Próximas  

NASA Astrophysics Data System (ADS)

We have started a new part of our program: ``Study of Evolution of AGNs & QSOs''. This new part is mainly a study of the relation between Starbursts and AGNs-QSOs in nearby galaxies (using our model of Evolutive, Composite & Explosive AGNs-QSOs). In particular, we have started spectrophotometric and imaging observations at CASLEO, Bosque Alegre, Gemini, Calar Alto, etc. This study also includes the analysis of Archive Data. Here we show our first results for NGC 1097. FULL TEXT IN SPANISH

Lípari, S.; Merlo, D.; Moyano, M.

165

Life-cycle stages of a Posthodiplostomum species (Digenea: Diplostomidae) from Patagonia, Argentina.  

PubMed

In Patagonia, populations of the galaxiid fish Galaxias maculatus are parasitized by metacercariae of a species of Posthodiplostomum (Digenea: Diplostomidae). The aim of this work was to describe larval and adult stages of this species in experimental and natural hosts from an Andean Patagonian lake. Specimens of G. maculatus and the pulmonate snail, Anisancylus obliquus, were collected in Patagua Lake. The snails were isolated in individual containers to observe emergence of cercariae, dissected, and examined under a stereoscopic microscope to record sporocysts and cercariae. Fish were examined to obtain metacercariae, and uninfected fish from Gutiérrez Lake were exposed to cercariae from A. obliquus to obtain experimental metacercariae. Chicks and mice were infected with metacercariae from naturally infected G. maculatus to obtain experimental adults. Specimens recovered belong to Posthodiplostomum sp. on the basis of morphological features. This is the first description of sporocysts, cercariae, metacercariae, and adults stages of a Posthodiplostomum species in Patagonia, including data about its natural intermediate hosts. PMID:23628085

Ritossa, Luciano; Flores, Verónica; Viozzi, Gustavo

2013-10-01

166

Biogeography of a southern hemisphere freshwater fish: how important is marine dispersal?  

PubMed

Galaxias maculatus is one of the world's most widely distributed freshwater fish. This species has a marine-tolerant juvenile phase, and a geographical range extending through much of the southern hemisphere. We conducted phylogeographic analyses of 163 control region haplotypes of G. maculatus, including samples from New Zealand (five locations), Tasmania (one location) and Chile (one location). A lack of genetic structure among New Zealand samples suggests that marine dispersal facilitates considerable gene flow on an intra-continental scale. The discovery of a Tasmanian-like haplotype in one of 144 New Zealand samples indicates that inter-continental marine dispersal occurs but is insufficient to prevent mitochondrial DNA differentiation among continents. The sister relationship of Tasmanian and New Zealand clades implies that marine dispersal is an important biogeographical mechanism for this species. However, a vicariant role in the divergence of eastern and western Pacific G. maculatus cannot be rejected. PMID:11091317

Waters, J M; Dijkstra, L H; Wallis, G P

2000-11-01

167

Ligophorus spp. (Monogenoidea: Dactylogyridae) parasitizing mullets (Teleostei: Mugiliformes: Mugilidae) occurring in the fresh and brackish waters of the Shatt Al-Arab River and Estuary in southern Iraq, with the description of Ligophorus sagmarius sp. n. from the greenback mullet Chelon subviridis (Valenciennes).  

PubMed

The gills of three of five species of mullets (Teleostei: Mugiliformes: Mugilidae) collected from the brackish and fresh waters of southern Iraq were infected with species of Ligophorus (Monogenoidea: Dactylogyridae) as follows: greenback mullet Chelon subviridis (Valenciennes) infected with Ligophorus lebedevi Dmitrieva, Gerasev, Gibson, Pronkina and Galli, 2012, Ligophorus bantingensis Soo and Lim, 2012, Ligophorus sagmarius n. sp., and Ligophorus fluviatilis (Bychowsky, 1949) Dmitrieva, Gerasev, Gibson, Pronkina, and Galli, 2012; Klunzinger’s mullet Liza klunzingeri (Day) with L. bantingensis, L. fluviatilis, and an apparently undescribed species of Ligophorus; and abu mullet Liza abu (Heckel) with L. bantingensis and L. fluviatilis. The keeled mullet Liza carinata (Valenciennes) and Speigler’s mullet Valamugil speigleri (Bleeker) were uninfected. L. sagmarius n. sp. is described, and L. lebedevi and L. bantingensis are redescribed. Available specimens of L. fluviatilis and the undescribed species of Ligophorus from Klunzinger’s mullet were insufficient for description. PMID:24022128

Kritsky, Delane C; Khamees, Najim R; Ali, Atheer H

2013-12-01

168

[Population genetic structure of the char species of the Northern Kuril Islands and the rank of the Dolly Varden Char in the system of the genus Salvelinus (Salmonidae: Teleostei)].  

PubMed

Analysis of the taxonomic position of most species and forms of the char (genus Salvelinus, Salmonidae: Teleostei) was made based on RAPD-PCR. The material was represented by samples from 29 populations from the Kuril Islands, coast of the Sea of Okhotsk, Kamchatka, Chukotka, Taymyr, Transbaikalia, the Kola Peninsula, Svalbard, Finland, and North America. It was shown that the genus Salvelinus splits into three well-justified clusters: (1) all the forms assigned to the Salvelinus alpinus--S. malma complex; (2) two samples of the White-Spotted Char from the Southern Kuril Islands and from Kamchatka; (3) two North American species, S. fontinalis and S. namaycush (samples of the North American species S. confluentis were absent from the collection). Analysis of the absolute values of genetic disctances of the S. alpinus--S. malma forms relative to S. leucomaenis, S. fontinalis, and S. namaycush revealed distances approaching the species rank between the following isolates: Frolikh Char, Mountain Char, Black Lake Char, Goggle-Eyed Char, and Neyva Char. Samples of Dolly Varden currently considered as "S. malma", do not constitute a separate cluster, falling within the group of the Arctic char S. alpinus. This conclusion is supported by the analysis of the results of three series of experiments by R. Phillips on ITS1 ribosome genes (Pleute et al., 1992; Phillips et al., 1995; Phillips et al., 1999). This indicates the infraspecific rank of malma within S. alpinus. Isolated populations of "Salvethymus svetovidovi" from the lake Elgygytgyn (Chukotka Peninsula) and of the char from the lake Chyornoye (Onekotan Island), recently described as S. gritzenkoi (Vasil'eva, Stygar, 2000), fell withing the S. alpinus--S. malma complex, the Onekotan char grouped together with another isolate from the same island. Comparison of genetic distances between the samples showed that the differences between the two isolated of Onekotan and migratory forms of the Kuril Islands are approximately equal, yet the homogeneity of the Chyornoye sample is higher than that of the other samples. The revealed 330-nucleotide diagnostic sequence of the Onekotan lake isolate showed identity of part of the fragment with a section of expressed DNA from the library of EST clones derived from the gills of Salmo salar, this possibly indicates the adaptive character of the evolution. PMID:17022488

Shubina, E A; Ponomareva, E V; Gritsenko, O F

2006-01-01

169

Análisis de la formación de galaxias en grupos  

NASA Astrophysics Data System (ADS)

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

Pérez, M. J.; Tissera, P.; García Lambas, D.

170

Dinámica de galaxias sin rotación: I. Modelos estacionarios  

Microsoft Academic Search

Several models, in the frame of Chandrasekhar theory of the dynamics of stellar systems, have been developed under the hypotheses of time independence, absence of macroscopic motions and equatorial and point axial symmetry. The obtained models have three first integrals in involution so that they determine integrable systems. These models can be applied to the study of the dynamics of

P. Cortés; F. Sala

1990-01-01

171

Estructuras circumnucleares en la galaxia Seyfert interactuante NGC 1241  

NASA Astrophysics Data System (ADS)

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

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

172

Superestructuras y las propiedades del clustering de galaxias brillantes  

NASA Astrophysics Data System (ADS)

This article is based on the results presented in Yaryura et al. (2012, MNRAS, 426, 708), where the clustering properties of galaxies is analyzed as a function of their large-scale environment. In order to characterize the environment on large scales, we use the catalogue of future virialized superstructures (FVS) by Luparello et al. (2011, MNRAS, 415, 964) and separate samples of luminous galaxies according to whether or not they belong to FVS. The correlations have similar amplitudes at scales r ? 1 h^{-1} Mpc. We have performed a similar analysis using a semi-analytic implementation in a ?CDM cosmological model, where we found that the cross-correlation functions depend on the large-scale structures in a similar way to the observations. FULL TEXT IN SPANISH

Yaryura, C. Y.; Lares, M.; Luparello, H. E.; Paz, D. J.; Lambas, D. G.; Padilla, N.; Sgró, M. A.

173

Cúmulos globulares y galaxias enanas en Pegasus I  

NASA Astrophysics Data System (ADS)

We present the first results of a photometric and spectroscopic study of the central region of the Pegasus I group. We have identified 1800 globular cluster candidates with g'_0<26 mag, and ˜ 60 possibles UCDs or young clusters, as well as the presence of at least two subpopulations of clusters in both dominant galaxies. We also present the brightness profiles and their Sérsic fits for two dwarf galaxies previously reported in the literature, as well as for a new dE,N candidate. We confirm that the two former galaxies are group members. FULL TEXT IN SPANISH

Faifer, F. R.; Escudero, C.; Smith Castelli, A. V.; González, N. M.; Forte, J. C.; Bassino, L. P.; Cellone, S. A.

174

Sistemas de galaxias luminosas rojas: Supercúmulos a partir de sobredensidades de galaxias en el catálogo fotométrico del SDSS.  

NASA Astrophysics Data System (ADS)

We identify luminous red galaxy (LRG) systems in the Sloan Survey, using a percolation algorithm. We find 737 systems with at least 4 members, on a total of 17977 LRGs in the range 0.30

Luparello, H.; Lares, M.; García Lambas, D.

175

Validating the use of embryonic fish otoliths as recorders of sublethal exposure to copper in estuarine sediments.  

PubMed

In this study we explore the use of fish otoliths ('earbones') as a tool for detecting exposure to heavy metals in sediments. Because otoliths are metabolically inert and incorporate chemical impurities during growth, they can potentially provide a more permanent record of pollutant exposure history in aquatic environments than soft tissues. To validate this technique we cultured embryos of a native Australian fish, the common Galaxias (Galaxias maculatus), in the laboratory on sediments spiked with copper in a concentration gradient. Our aims were to test whether exposure to copper contaminated sediments is recorded in the otoliths of embryos and determine over what range in concentrations we can detect differences in exposure. We found elevated copper levels in otoliths of embryos exposed to high copper concentrations in sediments, suggesting that otoliths can be used as a tool to track a history of exposure to elevated copper levels in the environment. PMID:23628888

Barbee, Nicole C; Greig, Alan; Swearer, Stephen E

2013-07-01

176

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

PubMed

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

Baker, C F

2014-02-01

177

Callosobruchus maculatus: A Seed Beetle with a Future in Schools.  

ERIC Educational Resources Information Center

Recommends the use of seed beetles for studying animal behavior and provides suggestions for practical and project assignments. Sources for obtaining the beetles and a list of the equipment needed for their study and maintenance are provided. Answers to common concerns are addressed. (DDR)

Dockery, Michael

1997-01-01

178

Component population study of Acanthocephalus tumescens (Acanthocephala) in fishes from Lake Moreno, Argentina.  

PubMed

Seasonal samples of all fish species from Lake Moreno were taken in order to determine the presence of paratenia, to evaluate the status of the hosts and to characterise the transmission of Acanthocephalus tumescens (von Linstow, 1896) at the component population level. Prevalence, mean abundance, mean intensity, numbers of gravid females, relative abundance of the different fish species, relative output of eggs and relative flow rates for each host species were computed. Acanthocephalus tumescens showed low host specificity, successfully parasitizing six out of eight fish species present in the lake. No paratenic infection was registered. If prevalence, mean abundance, and number of gravid females are considered, host species can be placed in a continuum from the most to least suitable as follows: Galaxias platei Steindachner, Diplomystes viedmensis (Mac Donagh), Oncorhynchus mykiss (Walbaum), Salvelinus fontinalis (Mitchill), Percichthys trucha (Cuvier et Valenciennes) and Galaxias maculatus (Jenyns). However, when parasite flow rates and egg output were calculated, including relative abundance of each fish species, the continuum was rearranged as follows: P. trucha, O. mykiss, G. platei / G. maculatus, S. fontinalis and D. viedmensis. The first four species would be the main contributors to the population of A. tumescens in this lake, P. trucha being the major one. Different regulatory and non-regulatory mechanisms are suggested. PMID:12735727

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

2003-03-01

179

Genomics and Mapping of Teleostei (Bony Fish)  

PubMed Central

Until recently, the Human Genome Project held centre stage in the press releases concerning sequencing programmes. However, in October 2001, it was announced that the Japanese puffer fish (Takifugu rubripes, Fugu) was the second vertebrate organism to be sequenced to draft quality. Briefly, the spotlight was on fish genomes. There are currently two other fish species undergoing intensive sequencing, the green spotted puffer fish (Tetraodon nigroviridis) and the zebrafish (Danio rerio). But this trio are, in many ways, atypical representations of the current state of fish genomic research. The aim of this brief review is to demonstrate the complexity of fish as a group of vertebrates and to publicize the ‘lesser-known’ species, all of which have something to offer. PMID:18629122

2003-01-01

180

The importance of cutaneous gas exchange during aerial and aquatic respiration in galaxiids.  

PubMed

The Canterbury mudfish Neochanna burrowsius was found to be a pseudo-aestivating galaxiid with a low metabolic rate and significant cutaneous oxygen uptake (c. 43%) in both air and water. Another galaxiid, inanga Galaxias maculatus, had a higher metabolic rate in both media but the proportion of oxygen uptake met by cutaneous respiration rose significantly from 38 to 63% when the fish were exposed to air. Besides its important role in oxygen uptake, the skin of both species also contributed significantly to excretion of carbon dioxide in air, indicating the critical role of the integument as a respiratory tissue. In air, G. maculatus may increase cutaneous gas exchange to meet metabolic demands owing to the reduced utility of the gills, but as emersed G. maculatus were only able to maintain metabolic rates at c. 67% of that measured in water, this strategy probably only permits short-term survival. By contrast, the low and unchanging metabolic rate in water and air in N. burrowsius is a feature that may facilitate tolerance of long periods of emersion in the desiccating environments they inhabit. PMID:24417441

Urbina, M A; Meredith, A S; Glover, C N; Forster, M E

2014-03-01

181

Estudio de Evolución de los Núcleos Activos de Galaxias y QSOs: II. Búsqueda de Supernovas en Galaxias Pr'oximas con AGNs y Starburst  

NASA Astrophysics Data System (ADS)

Several lines of observational evidences suggesting that supernovae and hypernovae events play a main role in evolution of galaxies, AGNs and QSOs. In order to search more detailed information, we have started a study and detection of supernovae and hypernovae in the nuclei of nearby active galaxies obtaining high-resolution spectra and images in the standard UBVRI filters mainly from CASLEO, Bosque Alegre and data from archive of HST, ESO and La Palma observatories. In this paper we present the first preliminary results obtained in this program. FULL TEXT IN SPANISH

Merlo, D.; Lípari, S.; Moyano, M.

182

Centro de Radioastronoma y Astrofsica Universidad Nacional Autnoma de Mxico  

E-print Network

Hubble Secuencia de Hubble Espectroscopía Galaxias Galaxias Galaxias Curso Imparte Taller Imparte Gustavo Bruzual Galaxias en el Valeria Buenrostro Sloan Sky Survey Martín Avalos 7a Escuela de Verano en

Islas, León

183

Estructura espacial de las órbitas caóticas en un modelo autoconsistente de galaxia elíptica  

NASA Astrophysics Data System (ADS)

Hemos logrado construir modelos autoconsistentes de sistemas estelares utilizando una aproximación cuadrupolar para el potencial. Esto nos permite determinar órbitas y exponentes de Lyapunov de objetos que tienen posiciones y velocidades equivalentes a las que se obtienen de la funcón de distribución del sistema. La distribución espacial de las órbitas caóticas exhibe considerable estructura y, lo que es más importante aún, los valores de los exponentes de Lyapunov calculados sobre intervalos finitos de tiempo, muestran una fuerte correlación con el comportamiento de la órbita en esos mismos intervalos, por lo que permiten reconocer distintos subsistemas con diferentes distribuciones espaciales.

Muzzio, J. C.

184

Propiedades estadísticas de galaxias en las futuras estructuras más grandes del universo  

NASA Astrophysics Data System (ADS)

Superclusters of galaxies are the largest isolated structures in the universe. We study statistical properties of clustering of galaxies within superclus- ters, using a catalogue calibrated to identify future bound superstructures. We use a volume limited sample (z < 0.1) of spectroscopic galaxies from SDSS-DR7 to select luminous galaxies as centers, and fainter galaxies as tracers, to compute the cross­correlation function of galaxies. We find that this function depends on the chosen centers: luminous galaxies in super- clusters show a higher cross­correlation with tracers. We define subsamples to obtain an unbiased estimation of the clustering, independent of luminos- ity and mass. The influence of large scale environment is seen for galaxies in SCG only for distances greater than ~ 1Mpc. FULL TEXT IN SPANISH

Lares, M.; Yaryura, Y.; García Lambas, D.

185

Relaciones fundamentales de la población de galaxias de tipo temprano del cúmulo de Antlia  

NASA Astrophysics Data System (ADS)

We present the results of a study of more than 100 early-type galaxies in Antlia Cluster, that span from giant ellipticals to dwarf ellipticals, covering a magnitude range of 11 magnitudes (M_{V_T} = -22 to -11). We perform surface photometry of these galaxies, and their total magnitudes, surface brightnesses and radii are determined on the basis of the Sérsic law fits. Finally, the fundamental relations between them are analyzed. FULL TEXT IN SPANISH

Calderón, J. P.; Bassino, L. P.; Cellone, S. A.; Smith Castelli, A. V.; Caso, J. P.

186

Interacciones de galaxias: sistemas co-rotantes y contra-rotantes  

NASA Astrophysics Data System (ADS)

In this paper we present a sample of interacting galaxy pairs with tidal tails. We perform a visual cassification according to the sense of rotation of the spiral arms of each member of the tidal system. We study general features of interacting galaxies such as mass content in stars (M^*), luminosity ratios and local environment through an analysis of the ?_5 parameter. FULL TEXT IN SPANISH

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

187

Diferenciación de Galaxias Activas de Líneas Delgadas a Partir de Diagramas BPT  

NASA Astrophysics Data System (ADS)

Classification of active galaxies is made through careful analysis of their spectra, either by measuring the width of the emission lines or comparing the flux ratios between these lines. One of the best known methods for this process is the use of BPT (Baldwin, Phillips, & Terlevich) diagrams which allow the distinction of different types of active galaxies. In this article we present the study of a sample of active galaxies with thin lines taken from the SDSS (Sloan Digital Sky Survey) whose flux ratios were measured and diagnostic diagrams were constructed, thus allowing the differentiation between starburst (or H II) galaxies and authentic type 2 active galactic nuclei (AGNs). We show that there are some objects with similar spectra that have been misclassified. FULL TEXT IN SPANISH

Torres, J.; Portilla, J. G.

188

Particle Swarm Optimization (PSO) en modelos semi-analíticos de formación de galaxias  

NASA Astrophysics Data System (ADS)

We present preliminary results of calibrations of a semi-analytic galaxy formation model performed using the Particle Swarm Optimization (PSO) technique. This method involves the exploration of the parameter space by random walks of a set of ``particles'' that share information between them. Thus, comparing the model results against a set of observables (e.g. luminosity functions, the relation between black hole mass and bulge mass, morphological fractions), the PSO method yields a set of best-fitting values for the free parameters of the model. FULL TEXT IN SPANISH

Ruiz, A. N.; Domínguez, M. J.; Padilla, N. D.; Cora, S. A.; García Lambas, D.; Tecce, T. E.; Gargiulo, I. D.; Muñoz Arancibia, A. M.

189

Galaxia: a code to generate a synthetic survey of the Milky Way  

E-print Network

We present here a fast code for creating a synthetic survey of the Milky Way. Given one or more color-magnitude bounds, a survey size and geometry, the code returns a catalog of stars in accordance with a given model of the Milky Way. The model can be specified by a set of density distributions or as an N-body realization. We provide fast and efficient algorithms for sampling both types of models. As compared to earlier sampling schemes which generate stars at specified locations along a line of sight, our scheme can generate a continuous and smooth distribution of stars over any given volume. The code is quite general and flexible and can accept input in the form of a star formation rate, age metallicity relation, age velocity dispersion relation and analytic density distribution functions. Theoretical isochrones are then used to generate a catalog of stars and support is available for a wide range of photometric bands. As a concrete example we implement the Besancon Milky Way model for the disc. For the ste...

Sharma, Sanjib; Johnston, Kathryn V; Binney, James

2011-01-01

190

Genetic variation, population structure and cryptic species within the black mudfish, Neochanna diversus, an endemic galaxiid from New Zealand.  

PubMed

To investigate the phylogenetic relationships and geographical structure among landlocked populations of the black mudfish, Neochanna diversus, mitochondrial DNA nucleotide sequence data were sampled from seven populations from the Waikato and Northland regions of New Zealand. The complete D-loop region was sequenced from 70 individuals, with 913 bp from the tRNA-pro end used in population and phylogenetic analysis. A tandem repeat array, which ranged in size up to 200 bp, was found in most populations at the 3' end of the D-loop that was not able to be aligned for analysis. Of the seven sites sampled, two from Northland exhibited significant sequence divergence from all other sites. There was also a clear distinction among remaining Northland sites and those from the Waikato. An additional 518 bp segment of the 16S region was sequenced from all sites and compared with the other New Zealand mudfish species, N. apoda, N. burrowsius and the Tasmanian mudfish Galaxias (Neochanna) cleaveri using Galaxias maculatus as an outgroup. Both D-loop and 16S sequence data provided strong evidence for a cryptic species of mudfish present in Northland. The significant genetic structure apparent in the black mudfish appears most probably to be attributed to geological conditions during the Pliocene, where peat wetlands became apparent in the Waikato while Northland consisted of disjunct 'islands'. Conservation and management of these populations must take into account the historical processes that have shaped these patterns of genetic diversity. PMID:9919697

Gleeson, D M; Howitt, R L; Ling, N

1999-01-01

191

A new hedrurid species (Nematoda) from galaxiid fishes in Patagonia (Argentina) and infection of amphipods as intermediate host.  

PubMed

During a parasite survey of galaxiid fishes (Galaxiidae) from Patagonian Andean lakes, a new species of nematode, Hedruris suttonae n. sp. was collected from the stomach of the native Galaxias maculatus (Jenyns) and G. platei (Steindachner). Specimens were examined by light and scanning electron microscopy, especially head morphology, female caudal prehensile structure, and distribution of spines. The new species is distinguished by body and tail size, morphology and size of spicules, the arrangement of caudal papillae in the male, the female caudal hook, and size of eggs. Hyalella patagonica (Ortmann), a Neotropical species of Amphipoda, is reported as its natural intermediate host. Data regarding prevalence and mean intensity in the intermediate and definitive hosts are included. The diet and habitat of the hosts, the percentage of gravid females, the high values of prevalence, and mean intensity in galaxiid fishes, as well as the wide distribution of H. suttonae , collectively indicate that, in these oligotrophic Andean lakes, G. maculatus and G. platei are true definitive hosts of this nematode. PMID:19737026

Brugni, Norma L; Viozzi, Gustavo P

2010-02-01

192

[Parasitism in fishes and human riverside communities of the Huillinco and Natri lakes (Great Island of Chiloé), Chile].  

PubMed

In April and December 1989, 35 fish from Lake Huillinco (42 degrees 48'S, 74 degrees 02'W) and 36 fish from Lake Natri (42 degrees 48'S, 73 degrees 50'W), in the Great Island of Chiloé (Chile) were examined. Coprological samples from 159 persons, 17 dogs, 19 pigs and 4 cats from around both lakes were examined for Diphyllobothrium spp. infection. In the Lake Huillinco the following helminths of fishes were determined: Contracaecum sp. and Hysterothylacium sp. in Salmo trutta, Cauque mauleanum and Eleginops maclovinus; Dichelyne (Cucullanellus) dichelyneformis in S. trutta and E. maclovinus and Scolex pleuronectis in S. trutta. One specimen of Mugil cephalus did not show helminth parasites. Prevalence of infection were greater for Contracaecum sp. in S. trutta (75.0%) and C. mauleanum (76.0%); and Hysterothylacium sp. in E. maclovinus (75.0%). Mean intensity was higher for D. (C.) dichelyneformis in E. maclovinus. Contracaecum sp. in S. trutta, Oncorhynchus mykiss, Oncorhynchus kisutch and Galaxias maculatus; Acanthocephalus sp. in S. trutta and G. maculatus, S. pleuronectis in O. mykiss and Cystidicoloides sp. in G. maculatus were determined at Lake Natri. Prevalence and intensity of infection were higher for Contracaecum sp. in S. trutta and O. kisutch. Infection by Diphyllobothrium sp. was determined in one domestic cat. Prevalence of infection by intestinal protozoan and helminths in human population only showed significative differences for Ascaris lumbricoides and Trichuris trichiura that were higher in the Lake Huillinco. Importance of natural infection by helminth parasites for fish in cultured condition and possible mechanisms of infections in relation to the diet of fishes are discussed. PMID:2152358

Torres, P; Ruíz, E; Rebolledo, C; Mira, A; Cubillos, V; Navarrete, N; Gesche, W; Montefusco, A; Valdés, L; Alberdi, A

1990-01-01

193

The relative importance of genetic and nongenetic inheritance in relation to trait plasticity in Callosobruchus maculatus  

E-print Network

The relative importance of genetic and nongenetic inheritance in relation to trait plasticity and nongenetic mechanisms of inheritance is predicted to be related to the degree of trait plasticity, with nongenetic inheritance playing a greater role in the cross-generational trans- mission of more plastic traits

Bonduriansky, Russell

194

Paternal Investment in the Seed Beetle Callosobruchus maculatus (Coleoptera: Bruchidae): Variation Among Populations  

E-print Network

recessive or partially recessive alleles if they are sex-linked rather than autosomal (Charlesworth et al the intrapopulation (parental) crosses, suggesting additive genetic autosomal inheritance. This result differs from. For example, recessive alleles are shielded from selection when heterozygous but are exposed to selection when

Savalli, Udo M.

195

O.41 - Efficacy of various non-chemical methods against pulse beetle, Callosobruchus maculatus Fab  

Microsoft Academic Search

Pulses (grain legumes) are excellent sources of proteins (20-40%), carbohydrates (50-60%) and are fairly good sources of thiamin, niacin, calcium and iron. In India, over 200 species of insects have been recorded infesting various pulses both in the field and storage. Among these, the pulse beetles Callosobruchus spp. are the major pests in storage. Generally, infestation starts in the field

S. Bhalla

2008-01-01

196

Effects of cholinergic and noradrenergic agents on locomotion in the mudpuppy ( Necturus maculatus )  

Microsoft Academic Search

Some neurotransmitters act consistently on the central pattern generator (CPG) for locomotion in a wide range of vertebrates.\\u000a In contrast, acetylcholine (ACh) and noradrenaline (NA) have various effects on locomotion in different preparations. The\\u000a roles of ACh and NA have not been studied in amphibian walking, so we examined their effects in an isolated spinal cord preparation\\u000a of the mudpuppy

M. Fok; R. B. Stein

2002-01-01

197

A possibility to achieve genetic transformation in the platyfish-swordtail system ( Platypoecilus maculatus — Xiphophorus helleri )  

Microsoft Academic Search

Summary In order to determine how informative homologous donor DNA might be made available to propigment cells of the recipientXiphophorus helleri for transformation, labelled heterologous DNA fromE. coli was injected into the neural crest region or the yolk sac of embryos of the recipient. On the basis of the degradation rate of the donor DNA and the incorporation rate of

M. Schwab; J. Vielkind; F. Anders

1976-01-01

198

Immunocytochemical localization of serotonin in the brain and pituitary gland of the platyfish, Xiphophorus maculatus  

Microsoft Academic Search

Immunoreactive serotonin (ir-5HT) containing cells were localized in the brain and pituitary gland of the platyfish by use of immunoperoxidase procedures. In the brain, ir-neurons were found lining the wall of the third ventricle and in its lateral and posterior recesses. More caudally, ir-perikarya were found in the valvular portion of the cerebellum and in the raphe region. Ir-5HT was

Henrietta Margolis-Kazan; Leslie R. Halpern-Sebold; Martin P. Schreibman

1985-01-01

199

Patterns of gonad structure in hermaphroditic gobies (Teleostei Gobiidae)  

Microsoft Academic Search

Hermaphroditism has been reported for a small number of gobiid fishes, but the extent of this sexual pattern within the family is not known. Gonad structure was examined in one or more species from twenty-one gobiid genera. No evidence of hermaphroditism was found in the species selected from 14 genera. Laboratory studies supported the conclusion of gonochorism for the examined

Kathleen S. Cole

1990-01-01

200

New microsatellites primers for plaice, Pleuronectes platessa L. (Teleostei: Pleuronectidae)  

Microsoft Academic Search

Seven microsatellite loci were developed for Pleuronectes platessa, a commercially impor- tant flatfish found throughout northern European waters. The number of alleles per locus ranged from 11 to 33 and heterozygosities from 0.74 to 0.96. Cross-reactivity was tested against six other flatfish species. Significant amplification was found in all species from one to all seven of the loci.

G. Hoarau; D. Cook; W. T. Stam; J. L. Olsen

2002-01-01

201

NEW MICROSATELLITE PRIMERS FOR PLAICE, Pleuronectes platessa L. (TELEOSTEI : PLEURONECTIDAE)  

Microsoft Academic Search

Seven microsatellite loci were developed for Pleuronectes platessa, a commercially important flatfish found throughout northern European waters. The number of alleles per locus ranged from 11-33 and heterozygosities from 0.74-0.96. Cross reactivity was tested against six other flatfish species. Significant amplification was found in all species from one to all seven of the loci.

202

Homologies of the caudal fin rays of Pleuronectiformes (Teleostei)  

Microsoft Academic Search

Descriptions of pleuronectiform caudal fin rays, which vary considerably in composition, have been based on phenotypes (branched,\\u000a segmented, and unsegmented). To provide a more precise background to the phylogeny, the homologies of the caudal fin rays\\u000a are considered. The distinction between “principal rays” and “procurrent rays,” determined from their correspondence with\\u000a those of generalized percomorphs, is adopted. Also, the composition

Koichi Hoshino

2001-01-01

203

Life-history patterns of Cuban poeciliid fishes (Teleostei: Cyprinodontiformes).  

PubMed

The following work provides basic information about the life history of 10 Cuban species of the family Poeciliidae. Adult fish stocks were captured in their natural habitat, and litters obtained from them were raised and maintained in captivity for 19 weeks. For each species, we present the mean value of newborn length (TLo ), age at sexual maturity (AM), total length at sexual maturity (TLM), as well as the patterns of postnatal growth in aquarium conditions, which were described using size-age curves and nonlinear regression equations (Richards model). There are differences in growth dynamics among species. In general, growth rates differ for both sexes in all poeciliids studied, males maturing earlier than females, who reach higher values of total length at the 19th week (TLf ). Sexual size dimorphism could be explained by the specific roles of each sex (fecundity in females and early maturity in males) while differences in growth among species could be related to their distribution patterns in the wild. The data summarized in this contribution can be useful for the conservation of these fish species. PMID:22610913

Ponce de León, José L; Rodríguez, Rodet; León, Gunnary

2013-01-01

204

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

Microsoft Academic Search

BACKGROUND: The teleost order Lophiiformes, commonly known as the anglerfishes, contains a diverse array of marine fishes, ranging from benthic shallow-water dwellers to highly modified deep-sea midwater species. They comprise 321 living species placed in 68 genera, 18 families and 5 suborders, but approximately half of the species diversity is occupied by deep-sea ceratioids distributed among 11 families. The evolutionary

Masaki Miya; Theodore W Pietsch; James W Orr; Rachel J Arnold; Takashi P Satoh; Andrew M Shedlock; Hsuan-Ching Ho; Mitsuomi Shimazaki; Mamoru Yabe; Mutsumi Nishida

2010-01-01

205

Untersuchungen über das Farbmuster der Zebrabarbe Brachydanio rerio (Cyprinidae, Teleostei)  

Microsoft Academic Search

1.The genetics of some colour breeds was investigated. One gene is responsible for the degree of pigmentation of the melanophores (normal pigmentation versus slight pigmentation); another one controls the arrangement of the pigment cells (longitudinal stripes-spot pattern respectively); and a third one regulates the destruction of all the xanthophores and some of the iridophores and melanophores.2.The melanophores of the longitudinal

Frank Kirschbaum

1975-01-01

206

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

PubMed

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

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

1984-05-01

207

Bagrichthys majusculus, a new catfish from Indochina (Teleostei, Bagridae)  

Microsoft Academic Search

A b st r a c t. Bagrichthys majusculus, a new species of bagrid catfish from Indochina, is very similar to B. macracanthus and B. vaillantii, and has been previously identified as the former species. It differs from congeners in having a unique combination of the following characters: relatively large and broad mouth, well-developed oral dentition with homodont teeth, 10-13

Heok Hee NG

208

Rhodeus albomarginatus, a new bitterling (Teleostei: Cyprinidae: Acheilognathinae) from China.  

PubMed

Rhodeus albomarginatus, new species, is described from the Lvjiang River, a tributary flowing into Poyang Lake of Yangtze River basin, in Anhui Province, China. It is distinguished from all congeneric species by unique combination of characters: branched dorsal-fin rays 10; branched anal-fin rays 10-11; longest simple rays of dorsal and anal fins strong and stiff, distally segmented; pelvic fin rays i 6; longitudinal scale series 34-36; transverse scale series 11; pored scales 4-7; vertebrae 33-34; colour pattern of adult males (iris black, belly reddish-orange, central part of caudal fin red, dorsal and anal fins of males edged with white margin). PMID:24869865

Li, Fan; Arai, Ryoichi

2014-01-01

209

Masculinization mechanism of hybrids in bitterlings (Teleostei: Cyprinidae)  

Microsoft Academic Search

The sex ratio of bitterling hybrids (subfamily: Acheilognathinae) is often likely to be biased toward males. Artificial hybridization was carried out in 10 species of bitterlings (three genera) in order to elucidate the masculinization mechanism of hybrids. Tanakia himantegus never produced viable F1 hybrids with other species, while hybrids of most other species were viable. In terms of sex ratio

K. Kawamura; K. Hosoya

2000-01-01

210

Masculinization mechanism of hybrids in bitterlings (Teleostei: Cyprinidae).  

PubMed

The sex ratio of bitterling hybrids (subfamily: Acheilognathinae) is often likely to be biased toward males. Artificial hybridization was carried out in 10 species of bitterlings (three genera) in order to elucidate the masculinization mechanism of hybrids. Tanakia himantegus never produced viable F1 hybrids with other species, while hybrids of most other species were viable. In terms of sex ratio and fertility, hybrids were clearly divided into two groups: congeneric Tanakia hybrids and others. Both male and female congeneric Tanakia hybrids were fertile. The sex ratio was nearly 1:1 in all groups of Tanakia hybrids. Except for the congeneric Tanakia hybrids, sterile males appeared predominantly in groups of hybrids in which females were very rare but remained fertile. Sterile intersexes were also observed in five hybrid groups: T. lanceolata (female) x Acheilognathus cyanostigma (male), Rhodeus uyekii (female) x T. lanceolata (male), A. rhombeus (female) x T. lanceolata (male), A. rhombeus (female) x T. limbata (male), and A. tabira tabira (female) x A. cyanostigma (male). In the development of male-predominant hybrids, although hybrid and control (parental species) hatching and survival rates do not differ, no females appeared in hybrids, contrary to the controls. Taking the female heterogametic sex-determining system (ZW) and the phylogenetic relationship of bitterlings into consideration, the masculinization mechanism of hybrids in bitterlings can be explained by the interaction of two sex chromosomes, derived from each parental species. The basic genetic sex in bitterlings is male (ZZ) and the derivative is female (ZW). When parental species are related, the sex phenotype of hybrids coincides with the genetic sex. However, when the parental species differ, the sex phenotype of the ZW genotype is reversed to become male by an abnormal interaction between the Z and W chromosomes. The rare appearance of females and intersexes in male-predominant hybrids might be due to complete or partial functional expression of the W chromosome. PMID:11218084

Kawamura, K; Hosoya, K

2000-01-01

211

Retinal organisation in goldeye and mooneye (Teleostei: hiodontidae).  

PubMed

This paper presents the results of a comparative investigation of the retinas of two Hiodontids, the goldeye (Hiodon alosoides) and the Mooneye (H. tergisus) employing light and electron microscopy, cell isolation techniques as well as microspectrophotometry. Contrary to the observations of previous workers these species possess a duplex retina. The photoreceptors are bundled in groups of 20 rods and 20 cones. They exhibit features which have hitherto not been observed in vertebrates. These are a) an ellipsoid divided in two parts by the myoid: b) tubules in cone outer segments and, c) large "lateral sacs" (accessory outer segments). Cones are immobile but the rods and epithelial pigment are capable of movement (retinomotor responses). The prominent reflecting layer consists of cuboid and rod-like crystals composed of uric acid. The inner layers are made up of three tiers of large horizontal cells, one of amacrine cells and scarce bipolar and ganglion cells. Bundle density is 1 700 per sq. mm. Roughly, one receptor bundle projects onto one bipolar and one ganglion cell suggesting that each bundle acts as a functional unit. The visual pigment of the mooneye absorbs maximally at 535 +/- 2 nm, and is based on vitamin A2 (porphyropsin). We suggest that all non deep-sea fishes with bundled receptors have duplex retinas and the adaptive mechanisms for vision in turbid waters are based on different morphological means as illustrated by the comparison with Stizostedion. PMID:704982

Wagner, H J; Ali, M A

1978-06-01

212

The mitogenome of Liobagrus marginatoides (Teleostei, Siluriformes:Amblycipitidae).  

PubMed

Liobagrus marginatoides is endemic to southwest China (Ding, 1994), according to morphological taxonomy, and it is very similar to Liobagrus nigricauda, but its population is much smaller. In this study, the complete mitochondrial genome sequence of L. Marginatoides has been obtained with polymerase chain reaction (PCR), which contains 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a non-coding control region with the total length of 16,498 bp. The gene arrangement and composition are similar to that of other vertebrates. Most of the genes are encoded on heavy strand, except for eight tRNA and ND6 genes. Just like most other vertebrates, the against bias of G has a universality in different statistics results. The complete mitochondrial genome sequence of L. Marginatoides would contribute to better understand population genetics and protect its genetic diversity. PMID:23521177

Jia, Xiang-Yang; Li, Ying-Wen; Wang, Deng-Qiang; Tian, Hui-Wu; Tu, Bin; Xiong, Xing; Li, Shu-Hua; Chen, Da-Qing

2013-12-01

213

Morphology of the ovotestis of Serranus atricauda (Teleostei, Serranidae)  

Microsoft Academic Search

.   Analysis of gonad organization and development revealed that Serranus atricauda is a functional simultaneous hermaphrodite. The ovary is classified as asynchronous. Oocyte growth is divided into five stages:\\u000a stage I (primary growth stage), stage II (yolk vesicle formation), stage III (vitellogenesis), stage IV (oocyte maturation)\\u000a and stage V (mature egg). The testis is of the unrestricted or lobular spermatogonial

María Mercedes García-Díaz; María José Lorente; José Antonio González; Víctor Manuel Tuset

2002-01-01

214

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

PubMed

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

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

2010-04-01

215

Life History of Roach, Rutilus rutilus (Cyprinidae, Teleostei)  

Microsoft Academic Search

The present study deals with aspects of the brain development in the roach, Rutilus rutilus, a common mid-European cyprinid fish. The morphogenesis of selected brain areas from hatching to early juveniles was examined on serial paraffin cross-sections. From early juveniles to large adults, brain growth was quantitatively analyzed by computer-aided planimetry. The hatchlings of roach show a cytologically distinct optic

Roland Brandstätter; Kurt Kotrschal

1989-01-01

216

La conexión rayos-X -- óptico en la NLR de la galaxia Mrk 573. Mecanismos de ionización.  

NASA Astrophysics Data System (ADS)

We analyze the ionizing mechanisms for the narrow-line region (NLR) of Mrk 573. The alignment of radio, optical and X-ray features suggest that some interaction may be taking place in this region. We investigate if the optical and X-ray emission are being generated in shock waves triggered by the interaction between the radio jet and the intergalactic medium. FULL TEXT IN SPANISH

Reynaldi, V.; Guainazzi, M.; Feinstein, C.; Combi, J. A.

217

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

PubMed

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

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

2012-01-01

218

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

PubMed Central

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

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

2012-01-01

219

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

PubMed

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

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

2014-01-01

220

Table 1: Examples of direct and indirect effects of parasites in biological invasions. Host(s)Parasite(s) system Direct effect of parasite on  

E-print Network

, Salmo trutta and native Galaxias fish. P: Native trematode parasites, e.g., Gobiomorphus breviceps Stokell and Galaxias anomalus Native Galaxias fish suffer increased exposure to trematode parasites Invasive tout displaces native Galaxias into low flow, higher temperature refuges, thereby increasing

Holt, Robert D.

221

Introduced brown trout alter native acanthocephalan infections in native fish  

E-print Network

galaxias (Galaxias anomalus) have been observed, suggesting that parasite dilution is occurring. 3. We used­parasite dynamics in native roundhead galaxias. 4. Field observations demonstrated higher infection intensity in introduced trout than in native galaxias, but only small, immature A. galaxii were present in trout

Poulin, Robert

222

Instrucciones para el uso del paquete ``La Expansi'on del Universo y la Ley de Hubble''  

E-print Network

: longitud de onda, efecto Doppler, espectroscop'ia, magnitud, galaxias. En la P'agina de CLEA hay un manual observando galaxias con un telescopio, para hacerles espectroscop'ia y determinar su corrimiento al rojo. 1 propia Galaxia, as'i como fuentes difusas y de formas no redondas que son las galaxias externas a la

Rodriguez, Luis F.

223

Club de Astronomia de Cimat Segunda Sesion  

E-print Network

Messier, 1764. 3. Galaxias M105: tipo: galaxia el´iptica; constelaci´on: Leo; magnitud 9.3; di- mensiones 5,4 � 4,8 ; distancia 26 millones AL; descubridor: Pierre Mechain, 1781. M81: tipo: galaxia espiral: Johan Bode, 1744. M82: tipo: galaxia irregular; constelaci´on: Osa Mayor; magnitud 8.4; dimensiones 11

Bor, Gil

224

VOLUME NINETEEN JANUARYMARCH 2005  

E-print Network

ASSOCIATIONincorporated Registration No. ACO27788J Galaxias form E. Never Never River, Dorrigo, NSW. Altitude 850 m. R research on the systematics of the mountain galaxias Galaxias olidus (Galaxiidae) species complex, including more new Galaxias species. The area of particular interest is located in the mid-north of New

Canberra, University of

225

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

PubMed Central

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

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

2012-01-01

226

Insecticidal and repellent activities of the essential oil of Callistemon citrinus (Myrtaceae) against Callosobruchus maculatus (F.) (Coleoptera: Bruchidae).  

PubMed

The essential oil of Callistemon citrinus (Curtis) leaves was extracted by hydro distillation and tested on female and male adults of Callosobruchus macullatus (F.) for insecticidal and repellent effects. GC-MS analysis was used to identify and quantify the volatile composition of the essential oil. Results showed that 1,8-cineole (34.2%) and ?-pinene (29.0%) were the major components of the oil. Callistemon citrinus oil was found to be toxic to adult insects when applied by fumigation. Responses varied according to the gender of the insect and exposure time. LC50 values were 12.88 and 84.4 ?L.?L(-1) for males and females, respectively. An increase in exposure time from 3 to 24 h caused an increase in mortality from 50% to 100% in males and from 15.5% to 85.2% in females, at the highest concentration (500 ?L.?L(-1)). The essential oil also had a repellent effect against C. macullatus in a filter paper arena test. After 2 and 4 h, 86% and 94%, respectively, repellent effects were demonstrated at the highest concentration of 0.4 ?L?.cm(-2). These observations suggest that C. citrinus essential oil may be usefully applied to control storage pests. PMID:23949717

Zandi-Sohani, N; Hojjati, M; Carbonell-Barrachina, Á A

2013-02-01

227

Is the habitation of acidic-water sanctuaries by galaxiid fish facilitated by natural organic matter modification of sodium metabolism?  

PubMed

Acidic waters of New Zealand's West Coast are hypothesized to be a refuge for native galaxiid fish, allowing them to escape predation from acid-sensitive invasive salmonid species. To determine the mechanisms by which galaxiids tolerate low pH, we investigated sodium metabolism in inanga Galaxias maculatus in response to water pH, short-term acclimation to acidic waters, the presence and source of natural organic matter (NOM), and fish life history. Contrary to expectation, inanga were physiologically sensitive to acid exposure, displaying inhibited sodium influx and exacerbated sodium efflux. Short-term (144 h) acclimation to acid did not modify this effect, and NOM did not exert a protective effect on sodium metabolism at low pH. Inanga sourced from naturally acidic West Coast waters did, however, display a sodium influx capacity (J(max)) that was significantly elevated when compared with that of fish collected from neutral waters. All inanga, independent of source, exhibited exceptionally high sodium uptake affinities (18-40 ?M) relative to previously studied freshwater teleosts. Although inanga displayed relatively poor physiological tolerance to acidic waters, their high sodium influx affinity coupled with their occupation of near-coastal waters with elevated sodium levels may permit habitation of low-pH freshwaters. PMID:22902374

Glover, Chris N; Donovan, Katherine A; Hill, Jonathan V

2012-01-01

228

New evidence on a cold case: trophic transmission, distribution and host-specificity in Hedruris spinigera (Nematoda: Hedruridae).  

PubMed

The life cycle of Hedruris spinigera Baylis, 1931 (Nematoda: Hedruridae) is determined here with the first formal identification of the parasite's intermediate host: the crustacean amphipod Paracorophium excavatum Thomson. Adult H. spinigera are redescribed from specimens collected from the stomach of fishes, Retropinna retropinna (Richardson) and Aldrichettaforsteri (Valenciennes), from Lake Waihola, New Zealand. Immature adults of the parasite collected from intermediate hosts (P. excavatum) are also described for the first time. The prevalence, abundance and intensity of infection of H. spinigera in several fish species are quantified along with the occurrence of P. excavatum, the parasite's intermediate host, in fish stomach contents. Although H. spinigera's transmission mode (trophic transmission) and fish diet potentially expose all fish species to infection, some level of host specificity must exist as parasite prevalence, abundance and intensity of infection vary greatly between potential definitive host species. We suggest here that the anatomy of the fish digestive tract and especially that of the stomach plays an important role in host suitability for H. spinigera. While P. excavatum is the only intermediate host in Lake Waihola, H. spinigera was found in six different fish species: Aldrichetta forsteri, Galaxias maculatus (Jenyns), Retropinna retropinna, Rhombosolea retiaria Hutton, Perca fluviatilis Linnaeus and Salmo trutta Linnaeus; although typical hedrurid attachment and mating positions were observed only in R. retropinna and A. forsteri. The limited distribution of H. spinigera is most likely due to that of its different host species (intermediate and definitive), all inhabitants of coastal fresh and brackish waters. PMID:20941914

Luque, José L; Vieira, Fabiano M; Herrmann, Kristin; King, Tania M; Poulin, Robert; Lagrue, Clément

2010-09-01

229

Microsatellite markers and mtDNA data indicate two distinct groups in dwarf galaxias, Galaxiella pusilla (Mack) (Pisces: Galaxiidae), a threatened freshwater fish from south-eastern Australia  

Microsoft Academic Search

Galaxiella pusilla is a small, non-migratory freshwater fish, endemic to south-eastern Australia and considered nationally threatened. To assist\\u000a in the conservation of the species, microsatellite markers were developed and used to characterize genetic variation in 20\\u000a geographically distinct populations across its range. Substantial genetic differentiation was found between an eastern (Victoria\\u000a east of the Otway Ranges and Tasmania) and western

R. A. Coleman; V. Pettigrove; T. A. Raadik; A. A. Hoffmann; A. D. Miller; M. E. Carew

2010-01-01

230

Estimación de la incerteza cinemática de los espectros obtenidos con REOSC (CAsLeo), Flamingos-2 y PHOENIX (Gemini) para observaciones de gas ionizado en galaxias  

NASA Astrophysics Data System (ADS)

The determination of the radial velocity curves of ionized gas in galaxies requires knowing the value of the internal kinematic uncertainly along the slit for the used spectrographs. We present preliminary results of the study of the variation of the measured radial velocity of both the telluric and comparison emission lines in the spatial direction. This was done for the spectrographs REOSC, Flamingos-2 (F2) and Phoenix. In particular we are interested in using this data to homogenize the rotation curves of nearby galaxies in large-scale ranges. These results will be also useful as references for those works that measure radial velocities of extended objects using only one emission line of ionized gas. FULL TEXT IN SPANISH

Gaspar, G.; Díaz, R. J.; Güunthardt, G.; Agüuero, M. P.; Camperi, J. A.; Gimeno, G.

231

Sistema de cúmulos globulares de la galaxia lenticular NGC 6861: en busca de indicios sobre la formación de las S0s.  

NASA Astrophysics Data System (ADS)

We present a preliminar photometric study of the globular cluster system (GCS), associated to the lenticular galaxy (S0) NGC 6861, which is located in a low density environment (d˜31.8 Mpc). It is based on GEMINI/GMOS images (GS-2010B-Q-2: PI Lilia P. Bassino) in the filters g', r', i' of three fields, one of them centered in the galaxy. We find a large number of GCs candidates and detect the presence of at least two sub-populations of GCs (``blue''/metal-poor and ``red''/metal-rich). The spatial distribution of ``red'' candidates presents a higher concentration toward the galaxy (associated to the bulge?), while the distribution of ``blue'' candidates is more homogeneus over the three fields (associated to the halo?). In the color-magnitud diagram, the ``blue'' GC candidates show a possible mass-luminosity relation, known as ``blue-tilt'', probably detected for the first time in a lenticular galaxy. FULL TEXT IN SPANISH

Escudero, C. G.; Faifer, F. R.; Bassino, L. P.; Calderón, J. P.; Caso, J. P.

232

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

PubMed

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

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

2013-04-01

233

Diet and food resource partitioning in koaro, Galaxias brevipinnis (Günther), and juvenile rainbow trout, Oncorhynchus mykiss (Richardson), in two Taupo streams, New Zealand  

Microsoft Academic Search

This study examined the diet of sympatric populations of migratory juvenile rainbow trout and landlocked koaro in the Waipehi and Omori Streams, Lake Taupo, New Zealand. In both species, diet was dominated, both numerically and by weight, by aquatic prey: Ephemeroptera, Trichoptera, and Diptera larvae were the most numerous prey items. Adult koaro and juvenile rainbow trout both fed on

Ian A. Kusabs; Stephen Swales

1991-01-01

234

Locomotor activity rhythms in cave fishes from Chapada Diamantina, northeastern Brazil (Teleostei: Siluriformes)  

Microsoft Academic Search

Previous studies on the locomotor activity of troglobitic (exclusively subterranean) species have shown that circadian rhythmicity may be reduced in populations evolving in the absence of zeitgebers such as daily cycles of light and temperature; therefore, circadian activity rhythms, although not infradian nor ultradian rhythms, seem to have been selected by external, ecological factors. We studied the locomotor activity of

E Trajano; L Duarte; L Menna-Barreto

2005-01-01

235

Drift ecology of western catostomid larvae with emphasis on Warner suckers, Catostomus warnerensis (Teleostei)  

Microsoft Academic Search

We studied drift ecology of Warner sucker, Catostomus warnerensis, larvae in streams of Warner Valley, Oregon in 1992 and 1993 in part to determine whether downstream transport of larvae limits juvenile recruitment. Variation in runoff for the two years was extreme, where peak discharge in 1992 was two orders of magnitude lower than peak discharge in 1993. We deployed drift

Tom B. Kennedy; Gary L. Vinyard

1997-01-01

236

Comparative studies of follicle cells in testes of Glyptocephalus stelleri and Pleuronectes pinnifasciatus (teleostei, pleuronectidae)  

Microsoft Academic Search

Accessory cells were studied in early spermatogenesis of flatfishes Glyptocephalus stelleri and Pleuronectes pinnifasciatus using transmission electron microscopy. The morphological organization of accessory cells in G. stelleri was similar to that of Sertoli cells. In P. pinnifasciatus, these cells had morphological organization, which had not been previously described.

S. Yu. Neznanova; V. N. Ivankov; A. A. Reunov

2005-01-01

237

Site selection of Acanthochondria cornuta (Copepoda: Chondracanthidae) in Platichthys flesus (Teleostei: Pleuronectidae).  

PubMed

Acanthochondria cornuta (Copepoda: Chondracanthidae) (N=4841; prevalence: 80·0%; mean±s.d. [range] intensity: 28·8±24·0 [1-110] parasites) infected the branchial chambers of the European flounder, Platichthys flesus (L.), (N=210) according to an established spatial pattern. This was independent of host size. Higher intensities resulted, most frequently, in higher numbers of infection sites, probably due to increased intraspecific competition. Preferential infection of the ocular side was supported by the recorded abundance data and reflected, probably, the fish's bottom-dwelling behaviour. As the parasite develops from one stage into another, it seems to migrate towards different sites: the copepodites and pre-adult females occurred, mainly, in the holobranchs; the adults preferred the internal wall (non-gravid/post-gravid females; adult males) or the pseudobranchs (gravid females). The ventilating water current along with the blood supply are suggested as 2 major factors in determining parasite spatial distribution within the chamber. Parasite crowding in a restricted and narrow space of the posterior region of the internal wall was recorded frequently and resembled that previously reported for the plaice. Differences to other host-parasite systems previously studied should relate with the anatomy of the respiratory apparatus. Bigamous females are reported for the first time. PMID:21733262

Cavaleiro, F I; Santos, M J

2011-07-01

238

EVIDENCE FOR INBREEDING IN JUVENILE PLAICE, Pleuronectes platessa L. (TELEOSTEI: PLEURONECTIDAE)  

Microsoft Academic Search

Heterozygote deficiencies have been consistently observed in plaice. To investigate possible causes of this result, we first ruled out the possibility of genotyping artefacts. We then compared temporal changes in FIS estimates by genotyping sequential cohorts of individuals collected on a biweekly basis from two genetically distinct nursery grounds in the Dutch Wadden Sea and in Iceland. Strongly positive and

239

Seasonality of metazoan ectoparasites in marine European flounder Platichthys flesus (Teleostei: Pleuronectidae).  

PubMed

Seasonal occurrence of metazoan ectoparasites is described for the first time in marine European flounder, Platichthys flesus (L.). The parasitofauna, in this study monitored during 1 year, was found to be similar to that previously recorded for flounder. Moreover, specimens of Caligus sp. Müller, 1785 and Lepeophtheirus pectoralis (Copepoda: Caligidae), Acanthochondria cornuta (Copepoda: Chondracanthidae), Holobomolochus confusus (Copepoda: Bomolochidae) and Nerocila orbignyi (Isopoda: Cymothoidae), and also, a praniza larva (Isopoda: Gnathiidae), were isolated. From these, L. pectoralis and A. cornuta were the dominant parasites in all samples of flounder, while Caligus sp., H. confusus, N. orbignyi and the gnathiid praniza seemed to infect the flounder only occasionally. As far as the seasonality of infections is concerned, it differed considerably from that described for estuarine environments. Indeed, both prevalence and abundance of L. pectoralis and A. cornuta reached significant peaks in the summer, whereas the literature identifies the autumn as the season of maximum infection on estuarine flounder. Thus, the former period seems more favourable for the occurrence of epizooties of L. pectoralis and A. cornuta in flounder culturing systems running on seawater and operated in the studied or similar environments. PMID:19470193

Cavaleiro, F I; Santos, M J

2009-07-01

240

[Comparative studies of follicle cells in testes of Glyptocephalus stelleri and Pleuronectes pinnifasciatus (Teleostei, Pleuronectidae)].  

PubMed

Accessory cells were studied in early spermatogenesis of flatfishes Glyptocephalus stelleri and Pleuronectes pinnifasciatus using transmission electron microscopy. The morphological organization of accessory cells in G. stelleri was similar to that of Sertoli cells. In P. pinnifasciatus, these cells had morphological organization, which had not been previously described. PMID:15807438

Neznanova, S Iu; Ivankov, V N; Reunov, A A

2005-01-01

241

Abdominal macroparasites of commercially important flatfishes (Teleostei: Scophthalmidae, Pleuronectidae, Soleidae) in northwest Spain (ICES IXa)  

Microsoft Academic Search

This study investigated the helminth fauna of the abdominal viscera and cavity of 484 flatfishes caught in three areas off northwest Spain: the inner third of the Muros Estuary (MI), offshore from the Muros Estuary (ME) and offshore from the Arousa Estuary (AE). The following helminths were found: (a) nematodes—Cucullanus heterochrous Rudolphi, 1802, C. minutus Rudolphi, 1819, Anisakis simplex (Rudolphi,

Francisca Álvarez; Raúl Iglesias; Ana Isabel Paramá; José Leiro; Manuel Sanmart??n

2002-01-01

242

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

E-print Network

Abstract Background The Leporinus genus, belonging to the Anostomidae family, is an interesting model for studies of sex chromosome evolution in fish, particularly because of the presence of heteromorphic sex chromosomes only in some species...

Parise-Maltempi, Patrícia P; da Silva, Edson L; Rens, Willem; Dearden, Frances; O’Brien, Patricia CM; Trifonov, Vladimir; Ferguson-Smith, Malcolm A

2013-07-03

243

DNA barcoding at riverscape scales: assessing biodiversity among fishes of the genus Cottus (Teleostei) in northern  

E-print Network

their distributions. Species-level diversity has long been the primary metric by which biodiversity is measured Introduction Projections of a rapidly changing climate and increasing human population in North America have

244

A basal Pachyrhizodontid fish (Actinopterygii, Teleostei) from the Lower Cretaceous of the Tlayúa Quarry, Central Mexico  

Microsoft Academic Search

Michin csernai gen. et sp. nov. from the Early Cretaceous (Albian) limestones of the Tlayúa Quarry, Puebla State, Central Mexico, is assigned to the Teleost clade Pachyrhizodontoidei as it possesses the enlarged inner premaxillary tooth, which is a unique synapomorphy of this clade. Additionally, the occurrence of relatively primitive characters (e.g., united parietals, angular and articular completely fused, caudal fin

Jesús Alvarado-Ortega; Diogo de Mayrinck; Paulo M. Brito

2008-01-01

245

Osteology of Eubiodectes libanicus (Pictet & Humbert, 1866) and some other ichthyodectiformes (Teleostei): phylogenetic implications  

Microsoft Academic Search

The osteology of the ichthyodectiform Eubiodectes libanicus (Pictet & Humbert, 1866) from the Cenomanian of Lebanon is described on the basis of acid-prepared specimens. For comparative purposes, the osteology of other putative ichthyodectiforms is described or discussed. We focus on the description of hitherto poorly described species such as Chiromystus mawsoni Cope, 1885, Ghrisichthys bardacki (Cavin, 1997a), ‘Saurodon’ intermedius (Newton,

Lionel Cavin; Peter L. Forey; Samuel Giersch

2012-01-01

246

Rhynchodercetis regio, sp. nov., a dercetid fish (Teleostei: Aulopiformes) from Vallecillo, Nuevo León State, Northeastern Mexico  

Microsoft Academic Search

Description of Rhynchodercetis regio, sp. nov., from Upper Cretaceous (Turonian) sediments of Vallecillo, State of Nuevo León, northeastern Mexico is based on three specimens. Rhynchodercetis regio differs from the other species of Rhynchodercetis in the exclusive combination of characters that includes the proportions of the head with its standard length, the length of the preorbital area, and the presence of

Alberto Blanco; Jesús Alvarado-Ortega

2006-01-01

247

Review of Vallecillichthys multivertebratum (Teleostei: Ichthyodectiformes), a Late Cretaceous (early Turonian) \\  

Microsoft Academic Search

A complete description of Vallecillichthys multivertebratum Blanco and Cavin, 2003, is provided. This ichthyodectiform fi sh was collected in the Vallecillo Member of the Agua Nueva Formation (Upper Cretaceous: lower Turonian) at Vallecillo, Nuevo León State, northeastern Mexico. On the basis of a comparative study, this monospecifi c genus is recognized as member of the suborder Ichthyodectoidei and placed with

Alberto Blanco-Piñón; Jesús Alvarado-Ortega

248

Twilight migrations and foraging activities of the copper sweeper Pempheris schomburgki (Teleostei: Pempheridae)  

Microsoft Academic Search

During 1976 and 1977, movements and foraging activities of Pempheris schomburgki were studied on the shallow coral reefs of northeastern St. Croix, U.S. Virgin Islands. P. schomburgki emerge from daytime refuges on the backreef at about local sunset. Fifteen to 20 min after sunset, local milling groups move beyond the confines of the reef and assemble into larger groups. Twenty-five

W. B. Gladfelter

1979-01-01

249

A new marine gobiid species of the genus Clariger Jordan & Snyder (Gobiidae, Teleostei) from Taiwan.  

PubMed

A new species of Clariger Jordan & Snyder, 1901 was collected from northern Taiwan. The genus was previously known only from Japanese waters. This discovery is the first formal and southernmost record of these marine gobies from the waters of subtropical Taiwan. The new species, Clariger taiwanensissp. n., is distinguished from its congeners by a unique combination of features: (1) fin rays: dorsal-fin rays III, I/8; anal-fin rays modally I/8; and pectoral-fin rays modally 19 (2+16+1); (2) longitudinal dermal ridge on head with 6 barbels; and (3) specific coloration pattern: head and trunk dark brown with scattered pale spots and blotches; cheek, ventral portion of head sometimes pale with deep brown spots; pectoral-fin base with a dark brown band; and caudal fin mostly dark brown proximally and with alternating and irregular dark brown and pale bands distally. A diagnostic key to all nominal species from Japan and Taiwan is provided. PMID:22711994

Jang-Liaw, Nian-Hong; Gong, You-Hai; Chen, I-Shiung

2012-01-01

250

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

PubMed Central

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

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

2012-01-01

251

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

Microsoft Academic Search

Phylogenetic relationships of rabbitfishes (the family Siganidae), ecologically important components as primary consumers in coral reef communities, were studied using mitochondrial cytochrome b gene and nuclear ITS1 (internal transcribed spacer 1) sequence analyses. The analyses of 19 out of 22 species known in the Western Pacific region revealed that siganids are genetically clustered into three major clades, which are characterized

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

2007-01-01

252

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

PubMed

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

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

2007-10-01

253

Filling the gap: a fossil frogfish, genus Antennarius (Teleostei, Lophiiformes, Antennariidae), from the Miocene of Algeria  

Microsoft Academic Search

A new species of frogfish, Antennarius monodi sp. nov., is described from the Upper Miocene (Messinian) of Raz-el-Ain, near Oran, north-east Algeria. The type and only specimen of this taxon is the first articulated skeleton belonging to the family Antennariidae ever recorded as a fossil. The morphological and meristic characters observed support the inclusion of this species in the Antennarius

G. Carnevale; T. W. Pietsch

2006-01-01

254

PCR-based identification of adriatic specimen of three scorpionfish species (Scorpaenidae, Teleostei).  

PubMed

The identification of three scorpionfish species, the black scorpionfish (Scorpaena porcus Linnaeus, 1758), the large-scaled scorpionfish (S. scrofa Linnaeus, 1758) and the small red scorpionfish (S. notata Rafinesque, 1810) is possible in adults by morphometry, but often problematic in juveniles due to their similar phenotypes. To develop a molecular species identification tool, first, we have analyzed the genetic similarity of the three species by a PCR-based 'blind method' that amplified bands from various locations of the genome. We found high levels of nucleotide similarity between S. porcus and S. scrofa, whereas S. notata showed a higher level of divergence from the other two species. Then, we have searched these patterns for differences between the genomes of Adriatic specimen of these three species and identified several species-specific products in two of them. For the third one a species-specific primer pair amplifying from the 16S ribosomal DNA was designed. One marker for each species was cloned, sequenced and converted into Sequence Characterized Amplified Region (SCAR) markers amplified by specific primer pairs. The SCAR markers amplified robust bands of limited variability from the target species, while no or only occasional weak products were obtained from the other two, proving that they can be used for molecular identification of these three species. These markers can help the conservation and future analysis of these three species as well as their possible selection programs for aquaculture purposes. PMID:24873907

Saju, J M; Németh, Sz; Sz?cs, Réka; Sukumaran, Rashmi; Lim, Z; Wong, L; Orbán, L; Bercsényi, M

2014-06-01

255

Three new species of Alburnoides (Teleostei: Cyprinidae) from Euphrates River, Eastern Anatolia, Turkey.  

PubMed

Three new species of Alburnoides, Alburnoides emineae sp. n., Alburnoides velioglui sp. n., Alburnoides recepi sp. n., are described from the Euphrates River drainages (Persian Gulf basin) in eastern Anatolia, Turkey. Alburnoides emineae, from Beyazsu Stream (south-eastern Euphrates River drainage), is distinguished from all species of Alburnoides in Turkey and adjacent regions by a combination of the following characters (none unique to the species): a well developed ventral keel between pelvic and anal fins, commonly scaleless or very rarely 1-2 scales covering the anterior portion of the keel; a deep body (depth at dorsal-fin origin 31-36% SL); 37-43 + 1-2 lateral-line scales, 13½-15½ branched anal-fin rays; number of total vertebrae 41-42, modally 41, comprising 20-21 abdominal and 20-21 caudal vertebrae. Alburnoides velioglui, from S?rl?, Karasu, Divri?i and Sultansuyu streams (northern and northeastern Euphrates River drainages), is distinguished by a poorly developed ventral keel, completely scaled; a moderately deep body (depth at dorsal-fin origin 24-29% SL); 45-53 + 1-2 lateral-line scales, 11½ -13½ branched anal-fin rays; number of total vertebrae 41-42, modally 42, comprising 20-22 abdominal and 20-21 caudal vertebrae. Alburnoides recepi, from Merzimen Stream (southern Euphrates River drainage), is distinguished by a well developed ventral keel, completely scaleless; a deep body (depth at dorsal-fin origin 29-34% SL); 47-56 + 2-3 lateral-line scales; 13½-16½ branched anal-fin rays; number of total vertebrae 38-40, comprising 19-21 abdominal and 18-20 caudal vertebrae. PMID:24869683

Turan, Davut; Kaya, Cüneyt; Ekmekçi, F Güler; Do?an, Esra

2014-01-01

256

Paraliparis adustus and Paraliparis bullacephalus: two new snailfish species (Teleostei: Liparidae) from Alaska  

E-print Network

­3 spinules at or near the tip, anus positioned forward near the pectoral symphysis, and color uniform brown of the head, snout, and opercular flap, mouth size, and eye position. Keywords Paraliparis adustus Á six Paraliparis species as occurring in Alaskan waters and included accounts of three additional

257

The Hybrid Sole Inopsetta ischyra (Teleostei: Pleuronectiformes: Pleuronectidae): Hybrid or Biological Species?  

Microsoft Academic Search

Since it was first described as a biological species by Jordan and Gilbert in 1880, Inopsetta ischyra has been a disputed taxonomic unit, generally regarded in recent decades as an intergeneric hybrid between English sole Parophrys vetulus and starry flounder Platichthys stellatus, both of which are common in coastal waters of the eastern North Pacific. Here, we investigate this suspected

Daniel L. Garrett; Theodore W. Pietsch; Fred M. Utter; Lorenz Hauser

2007-01-01

258

Quantitative histological studies of the optic tectum in six species of Notropis and Cyprinella (Cyprinidae, Teleostei).  

PubMed

Significant differences in stratification and size of the visual layers of the optic tectum were found between three clear-water minnows (Notropis amabilis, N. boops, Cyprinella venustas) and three turbid-water minnows (N. atherinoides, N. bairdi, and C. lutrensis). Correlations among a variety of neural structures suggested the importance of stratum marginale (SM), stratum opticum (SO), and stratum fibrosum et griseum superficiale (SFGS), stratum griseum centrale (SGC) and stratum periventriculare (SPV) in vision, of stratum album centrale (SAC) and SGC for olfaction, and of SPV for the processing of acoustico-lateral information. PMID:1779132

Huber, R; Rylander, M K

1991-01-01

259

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

PubMed

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

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

2012-07-01

260

Mitogenomic Evidence for an Indo-West Pacific Origin of the Clupeoidei (Teleostei: Clupeiformes)  

PubMed Central

The clupeoid fishes are distributed worldwide, with marine, freshwater and euryhaline species living in either tropical or temperate environments. Regional endemism is important at the species and genus levels, and the highest species diversity is found in the tropical marine Indo-West Pacific region. The clupeoid distribution follows two general pattern of species richness, the longitudinal and latitudinal gradients. To test historical hypotheses explaining the formation of these two gradients, we have examined the early biogeography of the Clupeoidei in reconstructing the evolution of their habitat preferences along with their ancestral range distributions on a time-calibrated mitogenomic phylogeny. The phylogenetic results support the distinction of nine main lineages within the Clupeoidei, five of them new. We infer several independent transitions from a marine to freshwater environment and from a tropical to temperate environment that occurred after the initial diversification period of the Clupeoidei. These results combined with our ancestral range reconstruction hypothesis suggest that the probable region of origin and diversification of the Clupeoidei during the Cretaceous period was the tropical marine precursor to the present Indo-West Pacific region. Thus, our study favors the hypotheses of “Region of origin” and “Tropical conservatism” to explain the origins of the longitudinal and latitudinal gradients of clupeoid species richness, respectively. Additional geological and paleontological evidence further define the tropical marine paleo-region of origin as the eastern Tethys Sea region. The Cretaceous fossil record of the Clupeoidei is partially incongruent with the results here as it contains taxa found outside this region. We discuss three possible causes of conflict between our biogeographical hypothesis and the distributions of the Cretaceous clupeoid fossils: regional extinction, incomplete taxonomic sampling and incorrect timescale estimation. PMID:23431379

Lavoue, Sebastien; Miya, Masaki; Musikasinthorn, Prachya; Chen, Wei-Jen; Nishida, Mutsumi

2013-01-01

261

Characterization of ?-amylase activity in five species of Mediterranean sparid fishes (Sparidae, Teleostei)  

Microsoft Academic Search

In the present study, amylase activity existing in the gut of different species of sparid fish was measured and characterized. The study was conducted on five species of Mediterranean sparids, (F. Sparidae), some of which coexist in the same coastal waters; Pagrus pagrus, Pagellus erytrhinus, P. bogaraveo, Boops boops and Diplodus annularis. Main differences were found in the optimal pH

I Fernández; F. J Moyano; M D??az; T Mart??nez

2001-01-01

262

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

PubMed

Pethia rutila, a new species is described from Karnaphuli drainage, Mizoram, Northeast India. It is distinguished from its congeners in having a complete lateral line with 21-22 scales, an inconspicuous black humeral spot on the scale row below the 3rd and 4th lateral-line scales, a black blotch on the caudal peduncle centered above the insertion of the last anal-fin ray, overlapping lateral-line scales 16-18 or 17-19 and ½4/1/3½ scales in transverse line from dorsal-fin origin to pelvic-fin origin. PMID:25081166

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

2014-01-01

263

Systematics and biogeography of Cyprinella venusta (Cyprinidae: Teleostei) inferred from analysis of mitochondrial DNA  

E-print Network

Mitochondrial (mt)DNA restriction-site analysis was used to study systematics and biogeography of the blacktail shiner, Cyprinella venusta. Taxonomically, C. venusta is comprised of three subspecies: C. v. venusta, C.v. cercostigma, and C. v...

Kristmundsdottir, Asrun Yr

2012-06-07

264

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

PubMed Central

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

Knytl, Martin; Kalous, Lukas; Rab, Petr

2013-01-01

265

Feeding Habits of Whitebone Porgy, Calamus leucosteus (Teleostei: Sparidae), Associated with Hard Bottom Reefs off  

E-print Network

and hook-and-line fisheries (Huntsman 1976; Waltz et a1. 1982). Whitebone porgy are found in depths of 11. Manuscript accepted April 1989. Fishery Bulletin. U.S. 87: 935--944. Waltz et a1. 1982. they are much more abundant in rocky reef habitats (Wenner et a1. 1980; Waltz et a1. 1982). These hard bottom

266

Phylogenetics of notothenioid fishes (Teleostei: Acanthomorpha): Inferences from mitochondrial and nuclear gene sequences  

Microsoft Academic Search

Notothenioids represent an adaptive radiation of teleost fishes in the frigid and ice-laden waters of the Southern Ocean surrounding Antarctica. Phylogenetic hypotheses for this clade have resulted primarily from analyses of mtDNA gene sequences, and studies utilizing nuclear gene DNA sequence data have focused on particular sub-clades of notothenioid fishes. In this study, we provide the first phylogenetic analysis of

C.-H. Christina Cheng

2008-01-01

267

Systematics of the subgenus Oligocephalus (Teleostei: Percidae: Etheostoma) with complete subgeneric sampling of the genus Etheostoma.  

PubMed

The genus Etheostoma is the most diverse clade of freshwater fishes in North America. While studies have been performed with complete sampling of a single subgenus, none have included representatives of all remaining subgenera. The subgenus Oligocephalus is the largest, consisting of 25-27 species in four species groups, and its monophyly has never been clearly demonstrated. The monophyly of this subgenus and its constituent groups was tested using parsimony and Bayesian analyses of ND2 (mtDNA) and the first intron of S7 (nDNA) with complete species sampling from Oligocephalus and complete subgeneric sampling from Etheostoma. Although the subgenus Oligocephalus was not recovered as a monophyletic group in any analyses, monophyletic E. whipplei, Southwestern Darter, and E. spectabile (in part) species groups were recovered in all analyses. All analyses agree that E. okaloosae and both subspecies of E. hopkinsi are not closely related to other members of the subgenus Oligocephalus. E. exile is, however, presenting the strongest evidence yet that recognition of the subgenus Boleichthys is unwarranted. PMID:17158072

Lang, Nicholas J; Mayden, Richard L

2007-05-01

268

Systematics of the subgenus Oligocephalus (Teleostei: Percidae: Etheostoma) with complete subgeneric sampling of the genus Etheostoma  

Microsoft Academic Search

The genus Etheostoma is the most diverse clade of freshwater fishes in North America. While studies have been performed with complete sampling of a single subgenus, none have included representatives of all remaining subgenera. The subgenus Oligocephalus is the largest, consisting of 25–27 species in four species groups, and its monophyly has never been clearly demonstrated. The monophyly of this

Nicholas J. Lang; Richard L. Mayden

2007-01-01

269

A new species of western Atlantic lizardfish (Teleostei: Synodontidae: Synodus) and  

E-print Network

. bondi, S. foetens (Linnaeus, 1766), and S. intermedius (Agassiz, 1829) Benjamin W. Frable (contact- medius (Agassiz, 1829) (Sand Diver) and S. foetens (Linnaeus, 1766) (In- shore Lizardfish). A new species foetens (Linnaeus, 1766) (Inshore Lizardfish) are estimated to be at fully exploited levels as bycatch

270

Changes induced by cadmium in the kidney of Black Sea bream, Mylio macrocephalus (teleostei)  

SciTech Connect

Cadmium is known to cause injury to most of the internal organs of higher vertebrates. Chronic exposure of cadmium produces histopathological changes in the kidney in man and experimental animals and leads to its preferential accumulation in the liver and kidney. The toxic effects of cadmium on man and experimental animals such as rats, mice and rabbits have been extensively investigated. However, less is known about injurious effects of cadmium on fish, in particular marine fish species. In the present study, the time course of cadmium-induced renal toxicity and histopathological changes of the kidneys of the Black Sea bream, one of the mot common maricultural fish species in Hong Kong, after administration of cadmium chloride are described.

Ooi, V.E.C.; Law, F.K. (Chinese Univ. of Hong Kong (China))

1989-11-01

271

Chalinochromis cyanophleps, a new species of cichlid fish (Teleostei: Cichlidae) from Lake Tanganyika.  

PubMed

Chalinochromis cyanophleps is described from nine specimens, the largest 129 mm SL, from Namansi. It differs from other species of Chalinochromis in plain trunk colouration, absence of black stripes on the head, relatively narrow lips, presence of tricuspid jaw teeth, and presence of five rather than four dentary lateralis foramina. The blue iridescent stripe below the eye is shared with other lamprologin cichlids, but is broader and more conspicuous in C. cyanophleps. Chalinochromis cyanophleps occurs at depths between 6 and 45 m in rocky habitats along the Tanzanian coast of Lake Tanganyika, from Mvuna Island south to Kalala Island, a stretch of about 90 km. Field observations were made of specimens up to 18 cm total length. The COI DNA barcode sequence differs by 1.8% from that of C. popelini. PMID:24869876

Kullander, Sven O; Karlsson, Mikael; Karlsson, Magnus; Norén, Michael

2014-01-01

272

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

PubMed Central

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

Datovo, Alessio; de Pinna, Mario C. C.; Johnson, G. David

2014-01-01

273

Sexual Ornaments, Body Morphology, and Swimming Performance in Naturally Hybridizing Swordtails (Teleostei: Xiphophorus)  

PubMed Central

Determining the costs of sexual ornaments is complicated by the fact that ornaments are often integrated with other, non-sexual traits, making it difficult to dissect the effect of ornaments independent of other aspects of the phenotype. Hybridization can produce reduced phenotypic integration, allowing one to evaluate performance across a broad range of multivariate trait values. Here we assess the relationship between morphology and performance in the swordtails Xiphophorus malinche and X. birchmanni, two naturally-hybridizing fish species that differ extensively in non-sexual as well as sexual traits. We took advantage of novel trait variation in hybrids to determine if sexual ornaments incur a cost in terms of locomotor ability. For both fast-start and endurance swimming, hybrids performed at least as well as the two parental species. The sexually-dimorphic sword did not impair swimming performance per se. Rather, the sword negatively affected performance only when paired with a sub-optimal body shape. Studies seeking to quantify the costs of ornaments should consider that covariance with non-sexual traits may create the spurious appearance of costs. PMID:25329558

Johnson, James B.; Macedo, Danielle C.; Passow, Courtney N.; Rosenthal, Gil G.

2014-01-01

274

Aberrant gene expression at the creatine kinase loci during Barbus hybrid development (Cypriniformes, Teleostei).  

PubMed

The tissue specificity and ontogeny of creatine kinase (CK, EC 2.7.3.2) are reported for tiger, rosy, ruby, cherry and gold barbs, and in interspecific hybrids where the tiger barb is the maternal parent. The spatial expression of CK isoenzymes in Barbus is consistent with the tissue patterns reported in other teleosts. In general, as the taxonomic (genetic) distance between the parental species increases, a corresponding delay in embryonic gene expression occurs; suggestive of species-specific effector molecule/sensor gene induction thresholds. PMID:4006440

Frankel, J S; Wilson, R V

1985-01-01

275

Ontogenetic patterns of enzyme locus expression in Barbus hybrids (Cypriniformes, Teleostei).  

PubMed

The tissue specific patterns and ontogeny of sorbitol dehydrogenase (SDH, EC 1.1.1.14). lactate dehydrogenase (LDH, EC 1.1.1.27) and isocitrate dehydrogenase (IDH, EC 1.1.1.42) are reported for Barbus tetrazona (tiger barb), B. conchonius (rosy barb), B. nigrofasciatus (black ruby barb), B. titteya (cherry barb), B. sachsi (gold barb), and in interspecific hybrids where B. tetrazona is the maternal parent. The spatial and temporal expression of SDH, LDH and IDH isozymes in Barbus is consistent with those reported for other teleosts. As the genetic distance between the parentals used in forming the hybrid increases, allelic expression proceeds from synchronous to asynchronous, with an increasing delay in embryonic gene expression. These observations are consistent with the hypothesis that parental sensor genes differ in their response to maternally controlled regulatory signals; indicative of species specific effector/activator RNA molecule concentrations and sensor/receptor gene induction thresholds. PMID:4085206

Frankel, J S

1985-01-01

276

Enteroendocrine cells in the digestive tract of Barbus conchonius (teleostei, cyprinidae)  

Microsoft Academic Search

Just as in other cyprinids, three zones can be distinguished in the digestive tract of Barbus conchonius. A fat absorptive zone (65–75%), including the intestinal bulb, is followed by a protein absorptive zone (25–35%) and a small ion and water absorptive zone (<5 %). The main characteristics of these zones are described.

J. H. W. M. Rombout

1977-01-01

277

Evolutionary Relationships of the Plagopterins (Teleostei: Cyprinidae) from Cytochrome b Sequences  

Microsoft Academic Search

Sequences of cytochrome b (cytb) were used to examine composition and phylo- genetic relationships of cyprinid fishes of the tribe Plagopterini, endemic to the Great Basin and Lower Colorado River in southwestern North America. The pla- gopterin genera, Lepidomeda, Meda, Plagopterus, and Snyderichthys, were most closely affiliated with the chubs Couesius and Margariscus of northern and eastern North America. As

Thomas E. Dowling; C. Alana Tibbets; W. L. Minckley; Gerald R. Smith; J. D. McEachran

2002-01-01

278

Systematics and biogeography of Cyprinella venusta (Cyprinidae: Teleostei) inferred from analysis of mitochondrial DNA.  

E-print Network

??Mitochondrial (mt)DNA restriction-site analysis was used to study systematics and biogeography of the blacktail shiner, Cyprinella venusta. Taxonomically, C. venusta is comprised of three subspecies:… (more)

Kristmundsdottir, Asrun Yr

2012-01-01

279

Proliferation and differentiation of intestinal epithelial cells during development of Barbus conchonius (Teleostei, Cyprinidae)  

Microsoft Academic Search

The processes of proliferation, cell division and differentiation of intestinal epithelial cells have been studied during development of the fish, Barbus conchonius. On the 3rd day, nearly all cells of the presumptive gut proliferate. Once the intestinal epithelium begins to differentiate, a decreasing percentage of proliferative cells can be found. On the 7th day, when intestinal folds start to develop,

J. H. W. M. Rombout; H. W. J. Stroband; J. J. Taverne-Thiele

1984-01-01

280

Brain morphology and turbidity preference in Notropis and related genera (Cyprinidae, Teleostei)  

Microsoft Academic Search

Synopsis The size of seven neural structures was compared in 51 species of Notropis, Pteronotropis, Cyprinella, Luxilus, Lythrurus, and Hybopsis, and related to the turbidity of the species& habitat. This last parameter was assessed for each species by personal communication with 42 ichthyologists. To control for size differences among species, all analyses were performed on the residuals from a regression

Robert Huber; Michael K. Rylander

1992-01-01

281

Monosaccharides as energy resources during motility of spermatozoa in Leuciscus cephalus (Cyprinidae, Teleostei)  

Microsoft Academic Search

Spermatozoa of Leuciscus cephalus have the enzymatic outfit for glycolysis but lack lipase, phospholipase and glucosidase activities. Therefore, they are not able to utilize lipids and polysaccharides as energy resources. During motility they use monosaccharides as energy reservoirs: the intracellular glucose, galactose and fructose levels decrease significantly while lactate levels increase.

F. Lahnsteiner; R. A. Patzner; T. Weismann

1992-01-01

282

Early development of the zebrafish ( Danio rerio ) pharyngeal dentition (Teleostei, Cyprinidae)  

Microsoft Academic Search

In order to build a reference system to assess ongoing in vitro and in situ hybridisation experiments on epithelial-mesenchymal interactions governing odontogenesis in the zebrafish, we describe here the generation of the pharyngeal dentition, and the histological development of teeth up to fourteen days post-fertilization, using serial semithin sections, handmade and computer-assisted reconstructions and transmission electron microscopy. The tooth pattern

A. Huysseune; C. Van der heyden; J.-Y. Sire

1998-01-01

283

Insight Into the Origin of Endemic Mediterranean Ichthyofauna: Phylogeography of Chondrostoma Genus (Teleostei, Cyprinidae)  

Microsoft Academic Search

The Chondrostoma genus is widespread in Europe, with numerous endemic species in northern Mediterranean rivers. We reconstructed the phylogenetic relationships of this genus, using the whole cytochrome b sequence and compared the two freshwater fish dispersion hypotheses: (1) dispersion around the Mediterranean Sea during the Lago Mare phase of the Messinian salinity crisis (Bianco's hypothesis) and (2) an older and

J.-D. Durand; P. G. BIANCO; J. LAROCHE; A. GILLES

2003-01-01

284

Metabolic responses to food deprivation and refeeding in juveniles of Rutilus rutilus (Teleostei: Cyprinidae)  

Microsoft Academic Search

Effect of food deprivation and refeeding on metabolic parameters were studied in juvenile Rutilus rutilus, weighing 280–460 mg. Tissue hydration increased with the length of the starvation period, reaching a new steady state after 4–5 weeks. Total protein concentration remained constant at about 60% of dry body mass. The concentration of glycogen decreased during food deprivation, a new steady state

Gabriela Méndez; Wolfgang Wieser

1993-01-01

285

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

PubMed Central

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

Benjamin, M; Sandhu, J S

1990-01-01

286

Elimination of the nucleus in preovulatory oocytes of the rainbow trout, Salmo gairdneri Richardson (Teleostei).  

PubMed

A process of elimination of the nucleus in oocytes of the rainbow trout displaying eight different stages is described. The phenomenon was observed only in stage III of sexual maturity. Initially, there is a slight shrinkage of the oocyte accompanied by the loss of yolk granules. This is followed by a cytoplasmatic protrusion into the ovarian lumen, which is covered by the follicular wall. Subsequently, the latter is ruptured and the nucleus migrates toward the opening. Finally, the nucleus leaves the follicle together with a portion of cytoplasm and the occasionally undergoes a breakdown into fragments in the ovarian lumen. The relevance of this mechanism in the process of preovulatory follicular atresia is discussed. PMID:6883465

Schulz, R; Blüm, V

1983-01-01

287

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

PubMed

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

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

2014-11-01

288

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

NASA Astrophysics Data System (ADS)

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

Scheffel, A.; Kramer, B.

289

First record of the black bullhead Ameiurus melas (Teleostei: Ictaluridae) in Poland.  

PubMed

The North American catfish, the black bullhead Ameiurus melas, is recorded for the first time in Poland. The origin of these fish is not clear, but their presence may be associated with unregulated introductions by anglers. PMID:20537032

Nowak, M; Kosco, J; Popek, W; Epler, P

2010-04-01

290

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

PubMed

Abstract The complete mitochondrial genome of the natural triploid loach Misgurnus anguillicaudatus is a circular molecule of 16,646 bp in size, containing 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and 2 main noncoding regions (the control region and the origin of the light strand replication). Most of the genes are encoded on the heavy strand, except for ND6 and 8 tRNAs. The control region is 918 bp in length and located between the tRNA(Pro) and tRNA(Phe) genes, some typical conserved elements (TAS, CSB1-3 and CSB D-F) were found in this region. All these features reflect a typical vertebrate mitochondrial gene arrangement of the triploid M. anguillicaudatus. PMID:23815325

Yu, Yong-Yao; Li, Yan-He; Li, Ru-Wei; Wang, Wei-Min; Zhou, Xiao-Yun

2014-10-01

291

Male gonadal differentiation and the paedomorphic evolution of the testis in Teleostei.  

PubMed

Testis differentiation from representatives of the Otophysi (Cyprinus carpio), Percomorpha (Amatitlania nigrofasciata), and Atherinomorpha (Poecilia reticulata) was comparatively described. In the undifferentiated gonad of C. carpio, the primordial germ cells (PGCs) are scattered throughout the gonads while in A. nigrofasciata and P. reticulata the PGCs are restricted to the ventral periphery. In the dorsal region of the developing gonads, with the exception of C. carpio, somatic cell rearrangements result in the differentiation of the sperm duct. Pre-Sertoli cells wrap around single spermatogonia forming cysts that proliferate forming acinar-clusters. In C. carpio and A. nigrofasciata, the cysts in each acinar-cluster move away from each other, creating a central lumen. In C. carpio, the acinar-clusters then fuse to each other forming tubules that become lined by the germinal epithelium. Subsequently, the tubules anastomose dorsally and create the sperm duct. In A. nigrofasciata, the acinar-clusters elongate, forming lobules that individually connect to the sperm duct. These are lined by the germinal epithelium. In P. reticulata, the spermatogonial cysts remain in the acinar-cluster organization. Subsequently, developing ducts connect each cluster to the sperm duct and lobules subsequently develop. In the differentiated testis of C. carpio and A. nigrofasciata, spermatogonia are distributed along the lengths of the anastomosing tubules or lobules, respectively. However, in P. reticulata, the spermatogonia remain restricted to the terminal end of the lobules. Considering testis ontogeny, the spermatogonial acinar-cluster is the adult characteristic of more derived taxa that approximate the early gonad developmental stages of the basal taxa. PMID:24740886

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

2014-06-01

292

Molecular systematics and population structure in the North American endemic fish genus Cycleptus (Teleostei: Catostomidae)  

Microsoft Academic Search

The overarching theme of this research was to investigate hierarchical levels of relatedness in natural populations of the cycleptid fishes (blue suckers), a widespread genus in North America that is of conservation concern throughout. Phylogenetic analysis of mitochondrial DNA sequences revealed that the two described Cycleptus species, C. elongatus and C. meridionalis are not reciprocally monophyletic, yet do not share

Michael Lee Bessert

2006-01-01

293

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

PubMed

We studied the morphology and shape variation of the palatal organ and chewing pad of sucker fishes, family Catostomidae. The palatal organ is a muscularized structure that forms a large mass on the roof of the posterior part of the buccopharyngeal cavity in cypriniform fishes. It functions in coordination with the branchial arches to separate food items from inorganic debris during feeding. The palatal organ exhibits considerable variability in morphology among catostomids. It is shorter, narrower, and thinner in species of the subfamily Cycleptinae (e.g., Cycleptus elongatus) than in other catostomid subfamilies. The thickest and widest palatal organ is seen in species of the subfamily Ictiobinae (e.g., Ictiobus cyprinellus). The shape and size of the palatal organ generally varies between these extremes in species of subfamily Catostominae (e.g., Catostomus and Moxostoma species). Principal components analysis and analysis of variance has differentiated means of various palatal organ measurements for each monophyletic subfamily and tribe of Catostomidae with statistical significance. These results corroborate previously established typological classification of catostomids based on pharyngeal tooth count, pharyngeal tooth morphology, and diet. A keratinized chewing pad forms on the posterior surface of the palatal organ in catostomids or on a skeletal process in cyprinids and serves as an occlusion surface for pharyngeal teeth. The chewing pad is lunate in catostomids and generally ovoid in cyprinids. It is absent from the species of loaches (e.g., botiids, cobitids, and nemacheilids) and gyrinocheilids examined. A synonymy of terms used in the past to describe the palatal organ and chewing pad of Cypriniformes is provided. PMID:21598291

Doosey, Michael H; Bart, Henry L

2011-09-01

294

Detection of interstitial telomeric sequences in the Arctic charr (Salvelinus alpinus) (Teleostei: Salmonidae).  

PubMed

Highly polymorphic Arctic charr ( Salvelinus alpinus Linnaeus, 1758) chromosomes were studied using conventional and molecular methods. The diploid chromosome number in the studied individuals was 2n = 81 or 2n = 82, with a fundamental arm number (NF) = 100. These differences are due to Robertsonian fusions. Interindividual variation in the number and size of DAPI and CMA(3) positively stained chromatin sites was observed in studied specimens. In the case of two individuals, the subtelomeric region of the long arm (q) of the largest acrocentric chromosome (chromosome number 10) was positively stained by CMA(3) fluorochrome. Both primed in situ labelling (PRINS) and fluorescence in situ hybridization (FISH) revealed that this CMA(3)-positive region was flanked by telomeric sequences. Previously, the subterminal position of interstitial telomeric sequences located in the vicinity of the CMA(3)-positive guanine-rich chromatin have been described in two other Salvelinus species, brook trout ( Salvelinus fontinalis ) and lake trout ( Salvelinus namaycush ). Moreover, multichromosomal location and variation in size of CMA(3) bands have been observed in various Salvelinus taxa, including fishes with internally located telomeric sequences. These results suggest that relocation of CMA(3)-positive chromatin segments in these species may be facilitated by flanking interstitial telomeric sequences (ITSs). PMID:22166084

Pomianowski, K; Jankun, M; Ocalewicz, K

2012-01-01

295

Insight into the origin of endemic Mediterranean ichthyofauna: phylogeography of Chondrostoma genus (Teleostei, Cyprinidae).  

PubMed

The Chondrostoma genus is widespread in Europe, with numerous endemic species in northern Mediterranean rivers. We reconstructed the phylogenetic relationships of this genus, using the whole cytochrome b sequence and compared the two freshwater fish dispersion hypotheses: (1) dispersion around the Mediterranean Sea during the Lago Mare phase of the Messinian salinity crisis (Bianco's hypothesis) and (2) an older and more gradual colonization of the Mediterranean rivers (Banarescu's hypothesis). All phylogenetic analyses identified two levels of divergences, implying two radiation events in the Chondrostoma genus. The first radiation mainly concerned Mediterranean species, whereas the second one includes Danubian and Mesopotamian species. This phylogeographic pattern was already observed for the genus Squalius, which exhibits a similar geographic range distribution in Europe and probably is shared with several other Mediterranean genera, such as Scardinius, Rutilus, and TELESTES: Furthermore, assuming a molecular clock of 1% per million years, the first radiation appears consistent with a Messinian dispersion during the Lago Mare, 5.3 million years ago, whereas the second one may correspond to a Mesopotamian dispersion through the Black Sea to the Danube system. According to our results, the Lago Mare theory is strengthened, and a more recent and pre-Pleistocene colonization of the Danube from Mesopotamian freshwater fishes is suggested. PMID:12920103

Durand, J-D; Bianco, P G; Laroche, J; Gilles, A

2003-01-01

296

Observations on the reproductive and larval biology of Blennius pavo (Pisces: Teleostei)  

NASA Astrophysics Data System (ADS)

Social behaviour and spawning of adult Blennius pavo kept in the laboratory are described. Eggs are deposited in batches on the walls of artificial spawning places (PVC pipes). One male guards and tends the eggs of different females in one spawning place. Larval hatching occurs in groups according to oviposition. Minimum incubation temperature is around 14 15°C. Larval survival in 1-1 rearing jars is not related to larval total length but to density of larval stock. An experimental population of laboratory reared juvenile and adolescent B. pavo displays a male to female ratio of 1:1.4. Factors possibly influencing the sex ratio of this littoral fish are discussed in view of the situation in its natural environment.

Westernhagen, H.

1983-09-01

297

Ein septum papillaris im auge von Pantodon buchholzi pet. (Teleostei, Osteoglossiformes)  

Microsoft Academic Search

A horizontal septum subdivides the eye of the surface feeding fish Pantodon buchholzi into an upper and lower part. The numbers and ratio of the receptor cells and succeeding neurons are different in both parts. The functional importance of these facts is discussed.

Erich Schwartz

1971-01-01

298

Morphology of the Neotropical swamp eel, Synbranchus marmoratus (Pisces: Teleostei), with emphasis on adaptive features  

E-print Network

with the orbits placed far anteriorly. Elongation and cylindrification of *he skull result mainly from modification of the frontal, para- sphenoid, and pterygoid bones, along with the lower jaw. The osteocranium is composed of two major divisions... the cranial vault. Lateral projections of the prefrontal and frontal bones form, respectively, the anterior and posterior walls of the orbits. At the be- ginning of the cranial vault, wing-like lateral processes of the sphenotic bones mark the widest point...

Conner, John Van

2012-06-07

299

Cryptic Diversity and Venom Glands in Western Atlantic Clingfishes of the Genus Acyrtus (Teleostei: Gobiesocidae)  

PubMed Central

Examination of genetic data (mitochondrial cytochrome c oxidase I) for western Atlantic clingfishes revealed two distinct lineages within a group of individuals originally identified as Acyrtus artius. Subsequent investigation of preserved voucher specimens was conducted to reconcile the genetic data and the existing classification, which is based on morphology. In addition to discovering that one of the genetic lineages is an undescribed species, which we describe as Acyrtus lanthanum, new species, we found that the nominal species Acyrtus artius has a putative venom gland associated with the subopercle that has been overlooked since the species was described nearly 60 years ago. The new species lacks the subopercular gland as does Acyrtus rubiginosus, but one is present in the related Arcos nudus. Venom glands have not been reported previously for the Gobiesocidae, and the venom gland described herein for Acyrtus and Arcos represents the first example in teleost fishes of a venom gland associated with the subopercle. PMID:24825326

Conway, Kevin W.; Baldwin, Carole; White, Macaulay D.

2014-01-01

300

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

PubMed

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

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

2014-08-01

301

Migration and reproductive biology of Mugil liza (Teleostei: Mugilidae) in south Brazil.  

PubMed

The mullet Mugil liza occurs along the Atlantic coast of South America from Venezuela to Argentina, but 95% of the commercial catch is collected from south Brazil between São Paulo and Argentina. Mugil liza is a single spawner with oocyte development occurring synchronously in two groups. Spawning happens in marine areas and occurs after migration. The reproductive migration occurs from Argentina (38° S) to the southern Brazilian states (24-26° S) from April to July, with peak spawning in June between northern Santa Catarina and Paraná. The presence of hyaline oocytes was associated with high salinity and sea surface temperatures of 19-21° C, and followed the seasonal northward displacement of these oceanographic conditions. The average size at first maturity (Lm ) for both sexes was 408·3 mm total length, LT . Males (Lm ?=?400·1) matured earlier than females (Lm ?=?421·9 mm). Fecundity ranged from 818,992 to 2,869,767 oocytes (mean = 1,624,551) in fish that were between 426 and 660 mm LT . PMID:25040915

Lemos, V M; Varela, A S; Schwingel, P R; Muelbert, J H; Vieira, J P

2014-09-01

302

Polyphyly of the mail-cheeked fishes (Teleostei: Scorpaeniformes): evidence from mitochondrial and nuclear sequence data  

Microsoft Academic Search

Mitochondrial and nuclear DNA sequence data for 105 acanthomorph taxa are analyzed to address questions of scorpaeniform monophyly and relationships. The combination of 3425 aligned base pairs from the mitochondrial small subunit rDNA (12S), large subunit rDNA (16S), and tRNA-Val and the nuclear large subunit rDNA (28S), histone H3, and TMO-4c4 loci are analyzed. Representatives of all scorpaeniform suborders and

Ward C. Wheelerc

303

The infrabranchial musculature and its bearing on the phylogeny of percomorph fishes (osteichthyes: teleostei).  

PubMed

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

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

2014-01-01

304

A Unique Symbiosis in the Gut of Tropical Herbivorous Surgeonfish (Acanthuridae: Teleostei) from the Red Sea  

Microsoft Academic Search

Herbivorous surgeonfish (Acanthurus species) in the Red Sea harbor gut symbionts that include bacteria, trichomonadid flagellates, and a peculiar putative protist that attains densities of 20,000 to 100,000 cells per milliliter of gut contents. The structure, mode of reproduction, and within-gut distribution of the latter are described. This may be the first report of an organism of this type and

Lev Fishelson; W. Linn Montgomery; Arthur A. Myrberg

1985-01-01

305

Licht- und elektronenmikroskopische Untersuchungen an den Eihüllen der Elritze ( Phoxinus phoxinus [L.]; Teleostei, Cyprinidae )  

Microsoft Academic Search

Summary The oocytes of the minnowPhoxinus phoxinus were examined by light and electron microscopy. In stage I they are only enveloped by the primary oocyte membrane which extends microvilli towards the follicle epithelium. The development of the actual egg envelope, the cortex radiatus, starts early in stage II. The cortex radiatus differentiates soon into the cortex radiatus externus and the

R. Riehl; E. Schulte

1977-01-01

306

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

PubMed Central

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

Voltolin, Tatiana Aparecida; Mendonca, Bruna Bueno; Ferreira, Daniela Cristina; Senhorini, Jose Augusto; Foresti, Fausto; Porto-Foresti, Fabio

2013-01-01

307

Goblet cell types in intestine of tiger barb and black tetra (Cyprinidae, Characidae: Teleostei).  

PubMed

Histochemical properties of goblet cells in intestine of a stomach-less teleost, tiger barb (Puntius tetrazona), and a stomach-containing teleost, black tetra (Gymnocorymbus ternetzi), are described and compared. The intestine goblet cells were mostly wide in both species, but in tiger barb, some of them were markedly thinner. In black tetra, all the intestine goblet cells displayed magenta colour after PAS, whereas in the tiger barb, only the thinner goblet cells displayed such affinity. The latter cell type was coloured strongly magenta when the tissue was treated with alcian blue (pH 2.5) followed by PAS, whereas the wide goblet cells in tiger barb and all goblet cells in black tetra displayed mainly a blue colour after such treatment. Further, the goblet cells in both species were coloured cleanly blue after high iron diamine followed by alcian blue (pH 2.5). The intestine goblet cells in both species displayed a moderate affinity to WGA and concanavalin A lectins and no affinity to DBA. Most of the goblet cells displayed no affinity to PNA, but some of them in the tiger barb displayed a moderate or strong affinity to this lectin. The affinity to WGA was somewhat strengthened after pre-treatment with neuraminidase. These results suggest that tiger barb contains two types or variants of intestinal goblet cells: high numbers of wide cells filled by acidic, non-sulphated mucin and some thinner cells filled by neutral mucin. The intestine goblet cells in black tetra were filled by variable amounts of neutral and acidic mucin, but the total number of such cells is much less than in tiger barb. The present lectin and neuraminidase results suggest that the intestinal mucins in both species contain significant amounts of N-acetylglucosamine, sialic acid and glucose/mannose, but seem to lack N-acetylgalactosamine. However, some of these cells in tiger barb contain moderate to large amounts of galactose. Together, these results suggest significant species-specific features of the intestine goblet cells and mucin types in tiger barb and black tetra. In conclusion, the present results suggest that the diet and feeding habits in stomach-less teleosts compared with stomach-containing teleosts, greatly influence the number of intestine goblet cells and type of mucin in these cells. PMID:23952769

Leknes, I L

2014-10-01

308

Ultrastructure of hepatocytes in golden ide ( Leuciscus idus melanotus L.; Cyprinidae: Teleostei) during thermal adaptation  

Microsoft Academic Search

The morphological alterations of hepatocytes of golden ide, Leuciscus idus melanotus, following adaptation to low and high temperatures (14 and 28°C) were investigated by means of light and electron microscopy. The temperature-dependent behaviour of peroxisomes was visualized cytochemically with the alkaline diaminobenzidine medium; the morphological studies were supplemented by the biochemical determination of catalase activity.

Thomas Braunbeck; Karin Gorgas; Volker Storch; Alfred Völkl

1987-01-01

309

Spermatozoon ultrastructure of Gyliauchen sp. (Digenea: Gyliauchenidae), an intestinal parasite of Siganus fuscescens (Pisces: Teleostei).  

PubMed

The ultrastructure of the mature spermatozoon of Gyliauchen sp., a parasite of the dusky rabbitfish Siganus fuscescens, was studied by transmission electron microscopy. The spermatozoon possesses two axonemes of the 9+"1" pattern of Trepaxonemata, four attachment zones, one mitochondrion, a nucleus, cortical microtubules, external ornamentation of the plasma membrane, and spine-like bodies. The main characteristics of this spermatozoon are the presence of one mitochondrion, spine-like bodies not associated with the external ornamentation, and a posterior extremity of type 3 that is characterized by the following sequence: posterior extremity of the nucleus then posterior extremity of the second axoneme. Numerous other ultrastructural features are also discussed and compared to the digenean spermatology literature. This is the first study of a member of the Gyliauchenidae and the fourth within the Lepocreadioidea. The results show that many ultrastructural characters are variable within this superfamily and could be useful for phylogeny. PMID:22042438

Quilichini, Y; Foata, J; Justine, J-L; Bray, R A; Marchand, B

2011-10-01

310

The cryopreservation of spermatozoa of the burbot, Lota lota (Gadidae, Teleostei)  

Microsoft Academic Search

The cryopreservation of spermatozoa of a teleost fish, the burbot, Lota lota (Gadidae) was investigated. Cryopreserved semen had the highest motility rate (46.6±8.0%, fresh semen control 86.5±8.2%) and fertility (78.1±2.7% embryo survival in hatching stage, fresh semen control 82.2±2.9%) when 10% methanol, 1.5% glucose and 7% hen egg yolk were used as cryoprotectants. Freezing was performed in 0.5-ml straws in

Franz Lahnsteiner; Nabil Mansour; Thomas Weismann

2002-01-01

311

Microsatellites from the burbot ( Lota lota ), a freshwater gadoid fish (Teleostei)  

Microsoft Academic Search

We developed 21 polymorphic dinucleotide microsatellite loci, (CA) n and (CT) n , for the Holarctic freshwater fish, Lota lota , using an enriched genomic library protocol. The species has an interesting life history because winter-spawning adults migrate over long distances to form spawning aggregations, a behaviour which should maintain genetic homogeneity across large spatial scales. Availability of the reported

MATTHIAS SANETRA; AXEL MEYER

312

Genetic admixture of burbot (Teleostei: Lota lota) in Lake Constance from two European glacial refugia.  

PubMed

The burbot, Lota lota, is the only freshwater species of the codfish family and has a Holarctic distribution. Pleistocene glaciations caused significant geographical differentiation in the past, but its life history characterized by winter spawning migrations over large distances is likely to homogenize populations by contemporary gene flow. We investigated the population genetic structure of 541 burbots from Lake Constance and adjacent Rhine and Danube tributaries in Europe using the entire mitochondrial DNA (mtDNA) control region and 11 microsatellites. Microsatellites revealed considerable population divergence (F(ST) = 0.26) and evidenced recent bottlenecks in two Central European rivers. In accordance to previous evidence two main phylogeographic lineages (Atlantic and Danubian) were found co-occurring at similar frequencies in Lake Constance, where they currently undergo random mating as indicated by microsatellites. The Danubian lineage contributed only a small proportion to the lake's mtDNA diversity, and probably expanded within the lake shortly after its formation approximately 10,000-15,000 BP. The larger Atlantic haplotype diversity suggested a population expansion older than the lake itself. Levels of admixture at microsatellite loci were less obvious due to their high variability, and coalescence methods were used to estimate past admixture proportions. Our results reinforce a model of a two-step colonization of Europe by burbot from an ancestral Danubian refuge, and confirm the persistence of a secondary Atlantic refuge, as proposed to exist for other freshwater fish. We conclude that the present-day burbot population in Lake Constance bears the genetic signature of both contemporary gene flow and historical separation events. PMID:17032259

Barluenga, Marta; Sanetra, Matthias; Meyer, Axel

2006-10-01

313

Genetic admixture of burbot (Teleostei: Lota lota ) in Lake Constance from two European glacial refugia  

Microsoft Academic Search

The burbot, Lota lota , is the only freshwater species of the codfish family and has a Holarctic distribution. Pleistocene glaciations caused significant geographical differentiation in the past, but its life history characterized by winter spawning migrations over large distances is likely to homogenize populations by contemporary gene flow. We investigated the popu- lation genetic structure of 541 burbots from

MARTA BARLUENGA; MATTHIAS SANETRA; AXEL MEYER

314

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

PubMed Central

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

Tobler, Michael; Schlupp, Ingo

2005-01-01

315

Fish production of a temperate artificial reef based on the density of embiotocids (Teleostei: Perciformes)  

Microsoft Academic Search

The abundance of two embiotocids (Embiotoca jacksoni and Rhacochilus vacca) was surveyed continually from 1974 to 1998 on the breakwaters comprising King Harbor in Redondo Beach, California, and a nearby natural rocky-reef as a reference. Embiotocids provide an interesting model for reef-fish production because they are viviparous and their entire ontogeny can be observed on the reefs. We deduce that

Daniel J. Pondella; John S. Stephens; Matthew T. Craig

2002-01-01

316

Isolation and Characterization of the Etheostoma tallapoosae (Teleostei: Percidae) CENP-A Gene.  

PubMed

Both centromeric alpha-satellite sequences as well as centromeric protein A (CENP-A) are highly variable in eukaryotes. CENP-A, a histone H3 variant, is thought to act as the epigenetic "mark" for assembly of centromeric proteins. While most of the histone fold domain (HFD) of the CENP-A is fairly well conserved, a portion of this HFD as well as the N-terminal tail show adaptive variation in both plants and animals. Such variation may establish reproductive barriers that may lead to speciation. The family Percidae contains over 200 species most of which are within the subfamily Etheostomatinae. This subfamily represents a species rich radiation of freshwater fishes in North America and these species exhibit both allopatric and sympatric distributions. In order to study the evolution of CENP-A in percid fish species, we have isolated and characterized the CENP-A gene from Etheostoma tallapoosae by PCR based gene walking. As a result of this study we have demonstrated that the Tallapoosa darter CENP-A gene HFD sequences can be isolated from genomic DNA by nested PCR in a manner that does not lead to the amplification of the highly sequence related histone H3 gene. We also demonstrated that PCR based walking can be subsequently used to isolate the rest of the CENP-A gene and adjacent gene sequences. These adjacent gene sequences provide us with a primer binding sites for PCR isolation of the CENP-A gene from other percid species of fishes. An initial comparison of three percid species shows that the N-terminal tail of the percid CENP-A gene shows adaptive evolution. PMID:24710294

Fountain, Dyanna M; Kral, Leos G

2011-01-01

317

Sound-producing mechanisms and recordings in Carapini species (Teleostei, Pisces)  

Microsoft Academic Search

Carapus boraborensis, C. homei and Encheliophis gracilis are three species of Carapidae that display the ability to penetrate and reside in the holothurian Bohadschia argus. This study describes both the particular morphology of the sound-producing structures and, for the first time, the sounds produced by each species. The study of the structures composing the sound-producing system seems to indicate that

E. Parmentier; P. Vandewalle; J. P. Lagardère

2003-01-01

318

Swimming ability and its rapid decrease at settlement in wrasse larvae (Teleostei: Labridae)  

Microsoft Academic Search

Wrasses are abundant reef fishes and the second most speciose marine fish family, yet little is known of their larval swimming\\u000a abilities. In August 2010 at Moorea, Society Islands, we measured swimming ability (critical speed, Ucrit) of 80 settlement-stage\\u000a larvae (11–17 mm) of 5 labrid species (Thalassoma quinquevittatum [n = 67], Novaculichthys taeniourus [n = 6], Coris aygula [n = 5], Halichoeres trimaculatus [n = 1] and H. hortulanus

Jeffrey M. Leis; Amanda C. Hay; Michelle R. Gaither

2011-01-01

319

Glugea vincentiae n. sp. (Microsporidia: Glugeidae) infecting the Australian marine fish Vincentia conspersa (Teleostei: Apogonidae).  

PubMed

A parasite of the marine fish Vincentia conspersa was examined by light microscopy and transmission electron microscopy. This parasite develops in the subcutaneous tissue of the body and fins, forming spherical xenomas about 1-2 mm in diameter surrounded by a layer of amorphous material. The observed characteristics of the new parasite are in line with those of the other Glugea species; merogony takes place in the outer zone of the cytoplasm of the host cell, sporogony takes place in sporophorous vesicles, and mature spores are located in the central part of the xenoma. Meronts were cylindrical uninucleate or occasionally triradiate multinucleate, with plasmodia in direct contact with the host cytoplasm. Sporogonic plasmodia divided by multiple cleavage to produce sporoblast mother cells, which after binary fission became sporoblasts. Two types of spores were recognized, both uninucleate, i.e., ovoid or slightly ovoid microspores with a mean size of 5.1 x 2.2 microm and much less frequent as elongated oval macrospores with a mean size of 8.9 x 3.1 microm. The polar tube has between 12 and 14 coils arranged in 1, 2, or 3 layers. Taken together, these characteristics suggest that this microsporidian infecting V. conspersa is a new species of Glugea, which we have named Glugea vincentiae. PMID:15856891

Vagelli, A; Paramá, A; Sanmartín, M L; Leiro, J

2005-02-01

320

Stone loaches of Choman River system, Kurdistan, Iran (Teleostei: Cypriniformes: Nemacheilidae).  

PubMed

For the first time, we present data on species composition and distributions of nemacheilid loaches in the Choman River basin of Kurdistan province, Iran. Two genera and four species are recorded from the area, of which three species are new for science: Oxynoemacheilus kurdistanicus, O. zagrosensis, O. chomanicus spp. nov., and Turcinoemacheilus kosswigi B?n. et Nalb. Detailed and illustrated morphological descriptions and univariate and multivariate analysis of morphometric and meristic features are for each of these species. Forty morphometric and eleven meristic characters were used in multivariate analysis to select characters that could discriminate between the four loach species. Discriminant Function Analysis revealed that sixteen morphometric measures and five meristic characters have the most variability between the loach species. The dendrograms based on cluster analysis of Mahalanobis distances of morphometrics and a combination of both characters confirmed two distinct groups: Oxynoemacheilus spp. and T. kosswigi. Within Oxynoemacheilus, O. zagrosensis and O. chomanicus are more similar to one other rather to either is to O. kurdistanicus. PMID:24869808

Kamangar, Barzan Bahrami; Prokofiev, Artem M; Ghaderi, Edris; Nalbant, Theodore T

2014-01-01

321

The first molecular phylogeny of Chilodontidae (Teleostei: Ostariophysi: Characiformes) reveals cryptic biodiversity and taxonomic uncertainty.  

PubMed

Chilodontidae is a small family of eight described characiform species popularly known as headstanders. These small to moderately sized fishes are well known to aquarists, who prize their striking spotted pigmentation and unusual behaviors, and to systematists, who have revised both chilodontid genera in recent memory and studied their phylogenetic relationships using a comprehensive morphological dataset. However, no molecular phylogeny for the family has ever been proposed. Here, we reconstruct phylogenetic relationships for all eight known chilodontid species using three mitochondrial and two nuclear loci. Results largely agree with the previous morphological hypothesis, and confirm the monophyly of the family as well as its included genera, Caenotropus and Chilodus. The molecular topology differs slightly from the morphological hypothesis by placing Caenotropus maculosus rather than C. mestomorgmatos as the sister to the remaining three congeners, and by reconstructing the Curimatidae as the closest outgroup family, rather than the Anostomidae. However, the topologies supported by the morphological data were only slightly less likely and could not be rejected via Shimodaira-Hasegawa tests. Within Chilodus, two described species with distinctive pigmentation (C. fritillus and C. zunevei) appear embedded within the broad distributed C. punctatus clade, suggesting the presence of cryptic taxa with polymorphic pigmentation within the present concept of C. punctatus. Future work should combine morphological and molecular data to revisit the taxonomy and systematics of Chilodus and determine species limits within the C. punctatus-group sensu lato. PMID:24120449

Melo, Bruno F; Sidlauskas, Brian L; Hoekzema, Kendra; Vari, Richard P; Oliveira, Claudio

2014-01-01

322

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

PubMed

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

Greenfield, David W; Tornabene, Luke

2014-01-01

323

Genetic Linkage Map of Fishes of the Genus Xiphophorus (Teleostei: Poeciliidae)  

PubMed Central

Analysis of genotypes of 76 polymorphic loci in more than 2600 backcross hybrid individuals derived from intra- and interspecific genetic crosses of fishes of the genus Xiphophorus (Poeciliidae) resulted in the identification of 17 multipoint linkage groups containing 55 protein-coding loci and one sex chromosome-linked pigment pattern gene. Multipoint linkage analyses identified highly probable gene orders for 10 linkage groups. The total genome length was estimated to be ~18 Morgans. Comparisons of the Xiphophorus linkage map with those of other fishes, amphibians and mammals suggested that fish gene maps are remarkably similar and probably retain many syntenic groups present in the ancestor of all vertebrates. PMID:2004711

Morizot, D. C.; Slaugenhaupt, S. A.; Kallman, K. D.; Chakravarti, A.

1991-01-01

324

Population structure in the Gulf Killifish Fundulus grandis (Teleostei : Cyprinodontidae) inferred from allozymes and mitochondrial DNA  

E-print Network

(per filter) of a solution containing 0. 54 SDS, 5x SSC, 5x Denhardt's solution, and 0. 5 mg/ml denatured salmon sperm DNA. Filters were hybridized to an mtDNA probe labelled with ( P) dCTP (New England Nuclear, sp. act. =3000 Ci/mM) by random... using the formula (Weir and Cockerham, 1984) and the computer programs described in Weir (1990). The effective number of female migrants per generation were calculated using Wright's (1943) island model modified for mtDNA. The GENERATE program...

Gricius, Eric Edward

2012-06-07

325

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

NASA Astrophysics Data System (ADS)

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

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

2014-08-01

326

Macropharyngodon pakoko, a new species of wrasse (Teleostei: Labridae) endemic to the Marquesas Islands, French Polynesia.  

PubMed

A new species of wrasse, Macropharyngodon pakoko, is described from the Marquesas Islands, bringing the total number of species of the genus Macropharyngodon to 12. Macropharyngodon pakoko was found at depths from 0-42 m and is endemic to the Marquesas Islands. Macropharyngodon pakoko is similar to M. meleagris, which is widely distributed from the central and western Pacific to Cocos-Keeling in the Indian Ocean, but differs genetically and in several coloration characters: males with irregularly curved black humeral blotch with incomplete iridescent blue border; inverted irregular "U"- shaped band on the cheek; a small black spot at the upper base of the pectoral fin; and background color of the body greenish with faint bluish black spots on each scale. Females lack black pigment on the chest posterior to the ventral attachment of the gill membranes; reddish black blotches on the body are widely spaced, particularly on the head where they are more reddish and half the size of those on body; caudal fin with small, bright yellow spots arranged in narrow vertical bands with pale interspaces; pelvic fins pale with three reddish yellow cross-bands; a small black spot at the upper base of the pectoral fin; and small reddish spots along the base of the anal fin. Juveniles have irregular black blotches on the body, a small black spot instead of an ocellus posteriorly on the dorsal fin and lack large black spots and ocellus on the anal fin.  PMID:25283116

Delrieu-Trottin, Erwan; Williams, Jeffrey T; Planes, Serge

2014-01-01

327

The spermatozoon of the Chinese bitterling, Rhodeus sericeus sinensis (Cyprinidae, Teleostei).  

PubMed

The bitterling spermatozoon has been examined by electron microscopy using sectioned material and freeze-fracture replicas. Its structure is characterized by a higher degree of order than is seen in spermatozoa of related teleosts. The intramembrane particles in the cell membrane are arranged in a large (around 1 micron in diameter) hexagonal grating pattern at a certain site of the sperm head. The flagellum protrudes from a site slightly posteriorly to this hexagonal grating and is surrounded by a cytoplasmic sleeve that contains regularly spaced filaments in a helical arrangement. The sperm midpiece contains a large mitochondrion enclosed in an elaborate system of membranous cisternae and narrow tubules. Fertilization in the bitterling takes place in the gill chamber of freshwater mussels--a unique brood chamber and site of fertilization for a vertebrate. PMID:1913580

Guan, T L; Afzelius, B A

1991-07-01

328

Transparent-Scaled Variant of the Rosy Bitterling, Rhodeus ocellatus ocellatus (Teleostei: Cyprinidae).  

PubMed

Transparent-scaled variant (TSV) of the rosy bitterling Rhodeus ocellatus ocellatus (Kner) was observed on both morphology and heredity. Compared with the normal-scaled type (NST), TSV is characterized by the blackish coloration in both eyes and peritoneum, and the luminescent one over the whole body. Histologically, the density of guanophores containing reflecting platelets was conspicuously low, especially in scale, iris, choroid and peritoneum, while the increase in the number of goblet cells (mucous cells) was recognized all over the dermal/epidermal regions. The heredity of TSV was recessive and supposed to be controlled by a single pair of genes unrelated to sex, judging from the result of crossbreeding experiments between NST and TSV. In growth and reproduction, no difference was seen between these two phenotypes. Transparent-scaled variant of the rosy bitterling can be competent for a genetic marker in experimental and developmental biology. PMID:18466008

Kawamura, K; Hosoya, K; Matsuda, M

1998-06-01

329

Molecular cytogenetic study of the European bitterling Rhodeus amarus (Teleostei: Cyprinidae: Acheilognathinae).  

PubMed

The European bitterlings (Rhodeus amarus) from the Eastern locations were cytogenetically examined by conventional and molecular techniques. All analyzed individuals presented invariably the same chromosomal constitution of 2n = 48, with 8 metacentrics + 20 submetacentrics + 20 subtelo-acrocentrics and C-banding positive heterochromatin at the pericentromeric regions in most of the chromosomes. Moreover, some of the chromosomes had short arms entirely built with heterochromatin. GC-rich Ag-NORs (nucleolus organizer regions) were located at the short arms of two submetacentric chromosomes, and the length polymorphism of these regions was found. Multiple location of 28S rDNA sequences with fluorescence in situ hybridization signals was observed on the long and/or short arms of three submetacentric chromosomes including NOR regions and short arms of three to five acrocentric chromosomes in the studied fish. 5S rDNA sites were found on the short arms of two subtelocentric chromosomes, and telomeric repeats were localized at the ends of all chromosomes. Provided results have expanded our knowledge concerning genetic characteristics of the European bitterlings that may be profitable in the conservation programs of this endangered species. PMID:24677088

Kirtiklis, Lech; Ocalewicz, Konrad; Wiechowska, Marzena; Boro?, Alicja; Hliwa, Piotr

2014-04-01

330

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

PubMed

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

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

2014-05-01

331

Ovipositor ultrastructure of the striped bitterling Acheilognathus yamatsutae (Teleostei: Acheilognathinae) during spawning season.  

PubMed

The ovipositor of striped bitterling Acheilognathus yamatsutae was subjected to ultrastructure and histochemical analysis during spawning season using light and electron microscopy. Although the ovipositor of A. yamatsutae is a long cylindrical tube with smooth external surface, it was possible to confirm the presence of well-developed fingerprint structure using scanning electron microscopy. Internal aspect analysis of ovipositor revealed formation of 5-8 longitudinal folds. Cross section analysis revealed that the ovipositor is composed of an outer epithelial layer, a mid connective tissue layer, and an inner epithelial layer. The outer epithelial layer contains 7-9 cell layers composed mainly of epithelial and mucous cells. Result of AB-PAS (pH 2.5) and AF-AB reaction showed that mucous cells contained mainly acidic carboxylated mucosubstances. The connective tissue layer was loose and made mainly of collagen fibers and some muscle fibers, along with blood vessels and a small number of chromatophores. The inner epithelial layer, which is a single layer, is composed of columnar epithelia. Observation under transmission electron microscope enabled distinction of the outer epithelial layer into superficial, intermediate and basal layers. Although the types of cells in the superficial tissue layer were diverse, they all shared the development of glycocalyx covered microridges. The majority of epithelial cells in the intermediate layer were cuboidal shaped, while those in the basal layer were columnar. Two types (A and B) of secretory cells were observed in the outer epithelial layer. The connective tissue layer had two types of chromatophores including xantophore and melanophore, in addition to a well-developed nerve fiber bundles. Columnar epithelial cells, mitochondria-rich cells and rodlet cells were observed in the inner epithelial layer. Microvilli were well developed on the free surface of columnar epithelial cells. PMID:19631358

Jin, Young Guk; Park, Jung Jun; An, Chul Min; Lee, Jung Sick

2009-12-01

332

Immunzytochemische Untersuchungen an den Rodletzellen bei Cyprinidae (Teleostei, Pisces) zur Aufklärung ihrer umstrittenen Abwehrfunktion.  

E-print Network

??Da Rodletzellen heutzutage eine Funktion im piscinen Abwehrsystem zugeschrieben wird, die allerdings nur teilweise untermauert ist, wurden die Chaperone des endoplasmatische Retikulum und das Zytoskelett… (more)

Lugmayr, Simone

2008-01-01

333

Uric Acid in the Tapetum Lucidum of Mooneyes Hiodon (Hiodontidae Teleostei)  

Microsoft Academic Search

Tapeta lucida (ocular reflectors) of mooneyes, Hiodon tergisus and H. alosoides, lie in the pigment epithelium, the processes of which are packed with reflecting particles and also contain melanin granules. The reflecting particles are tiny birefringent crystals. On the basis of chromatography, u.v. spectroscopy and enzymic degradation (with uricase), it is concluded that the reflecting material contains uric acid. Mooneye

E. S. Zyznar; F. B. Cross; J. A. C. Nicol

1978-01-01

334

Morphology-diet relationships in four killifishes (Teleostei, Cyprinodontidae, Orestias) from Lake Titicaca.  

PubMed

This study explores the relationship between morphology and diet in four Andean killifishes (Orestias) from Lake Titicaca that are known to differ in habitat use. Species that fed preferentially on amphipods (Orestias albus) or molluscs (Orestias luteus) separated in multivariate space from other species that feed on cladocera and algae (Orestias agassii and Orestias jussiei). Generally, specimens feeding on cladocera were characterized by a short, blunt nose with a small mouth; whereas, specimens feeding on amphipods exhibited a long snout with a large mouth. Specimens including molluscs in their diet tended to have a larger posterior part of the head and the larger opercles than others; while the occurrence of substratum in gut content was generally related to a short but deep head. The present analysis suggests that the littoral O. jussiei has an intermediate phenotype and diet between the pelagic (O. agassii) and benthic (O. albus and O. luteus) species. Results suggest that resource partitioning was occurring and that several morphological traits relate to characteristics of the diet, and it is inferred that the benthic, the pelagic and the littoral zones in the lake host different prey communities constituting distinct adaptive landscapes. PMID:20735575

Maldonado, E; Hubert, N; Sagnes, P; De Mérona, B

2009-02-01

335

A new Pseudophoxinus (Teleostei, Cyprinidae) species from Asi River Drainage (Turkey)  

PubMed Central

Abstract Pseudophoxinus turani sp. n. is described from the ?ncesu Spring (Hassa-Hatay) drainage of Asi River, Turkey. It is distinguished from other Eastern Mediterranean Region Pseudophoxinus species by a combination of characters: lateral line incomplete, with 12–25 (commonly 16–21) perforated scales and 38–46+2-3 scales in lateral series (commonly 41–44+2-3); 10–11 scale rows between the lateral line and dorsal-fin origin; 3–4 scale rows between the lateral line and the pelvic–fin origin; dorsal fin with 7½ branched rays; anal fin commonly with 7½ branched rays; 8-11gill rakers on the first branchial arch; dorsal profile markedly convex with marked hump at the nape, ventral profile less convex than dorsal profile; a small, irregular, black blotch on the base of the caudal fin; mouth terminal, with slightly distinct chin, its corner not reaching vertical through anterior margin of eye; snout somewhat long, with rounded tip; and its length greater than eye diameter. PMID:24899855

Kucuk, Fahrettin; Guclu, Salim Serkan

2014-01-01

336

The Dorsal Filament of the Weakly Electric Apteronotidae (Gymnotiformes; Teleostei) Is Specialized for Electroreception  

Microsoft Academic Search

The Apteronotidae, a family of weakly electric fish from South America (Gymnotiformes), possess a structure called the dorsal filament with an unknown function and evolutionary origin. This study compared the gross anatomy of the dorsal filament of 13 species of apteronotids and used light microscopy to examine the filaments of Adontosternarchus balaenops, Apteronotus albifrons, and Apteronotus leptorhynchus. The dorsal filament

Cheryl R. Franchina; Carl D. Hopkins

1996-01-01

337

The dorsal filament of the weakly electric Apteronotidae (Gymnotiformes; Teleostei) is specialized for electroreception.  

PubMed

The Apteronotidae, a family of weakly electric fish from South America (Gymnotiformes), possess a structure called the dorsal filament with an unknown function and evolutionary origin. This study compared the gross anatomy of the dorsal filament of 13 species of apteronotids and used light microscopy to examine the filaments of Adontosternarchus balaenops, Apteronotus albifrons, and Apteronotus leptorhynchus. The dorsal filament is an unscaled, thin, tapering structure attached to a mid-dorsal groove on the posterior half of the fish's back. The interior of the filament is a gelatinous mucopolysaccharide matrix (connective tissue) containing blood vessels and a bilateral nerve in which nearly all the afferents are large (8-10 mu m) and heavily myelinated. The location of the anterior origin of the filament varies from 0.48 to 0.66 of the body length, posterior to the snout, in 13 species. The filament is covered with hundreds of large-type tuberous electroreceptors and some ampullary receptors, at approximately the same density and ratio as those on the nearby back. The morphology of the large-type tuberous receptors and their afferents suggests that they are phase-coding T-units. A double layer of epithelial cells separates the ventral side of the filament from the groove in the trunk of the fish, except at the anterior origin where the interior of the filament is continuous with the body. This specialized double epithelium could provide a high resistance barrier to electrical current. This study was unable to distinguish between two hypotheses: that the dorsal filament is a modified adipose fin (as suggested previously), retained only in this family of Gymnotiformes; or that it is a uniquely derived character of the Apteronotidae. PMID:9156779

Franchina, C R; Hopkins, C D

1996-01-01

338

Schistura andrewi, a new species of loach (Teleostei: Nemacheilidae) from Mizoram, northeastern India.  

PubMed

Schistura andrewi, a new species of loach, is described from a tributary of Kaladan River in Mizoram, northeastern India. It is distinguished from its congeners in having the following combination of characters: long axillary pelvic lobe; complete lateral line with 82-95 pores; 2 unbranched dorsal and anal fin rays; 6-7 broad, wider than interspace, black bars on the body; 2 rows of black spots horizontally across the dorsal fin; a deeply emarginate caudal fin, with 2 vertical rows of black spots across the fin, and 9 + 8 branched caudal fin rays. PMID:25283204

Solo, Beihrosa; Lalramliana, Lalramliana; Lalronunga, Samuel; Lalnuntluanga, Lalnuntluanga

2014-01-01

339

Phylogenetics of the marine sculpins (Teleostei: Cottidae) of the North American Pacific Coast.  

PubMed

With 92 species along the North American Pacific Coast, marine sculpins represent the most species-rich radiation of fishes in this region. I used the mitochondrial cytochrome b gene and the nuclear ribosomal S7 intron for 99 species (76 North American, 19 Asian, and four North Atlantic) to produce the most complete phylogenetic hypothesis yet generated for this assemblage. Maximum likelihood and Bayesian analyses produced highly similar tree topologies. While many previously proposed groupings based on morphology are recovered, the molecular data suggest that a number of genera are para- or polyphyletic. However, this analysis supports the monophyly of one large clade that is found exclusively along the North American Pacific Coast (Chitonotous-Ruscarius-Artedius-Orthonopius-Clinocottus-Leiocottus-Oligocottus). Some sibling species have disjunct ranges, suggesting allopatric speciation. However, many other sibling species have largely overlapping ranges, and repeated habitat shifts appear to have facilitated diversification. PMID:23099148

Knope, Matthew L

2013-01-01

340

Extended Breeding Season in the Marbled Goby, Pomatoschistus Marmoratus (Teleostei: Gobiidae), in the Venetian Lagoon  

Microsoft Academic Search

Life cycle and reproductive biology of the marbled goby Pomatoschistus marmoratus was studied in the Venetian Lagoon. Lifespan was determined by reading otoliths. The maximum age recorded was 17 months juveniles occurred in samples from July to November. Nests were found in two different periods: from the middle of April to the middle of July and from the middle of

Carlotta Mazzoldi; Maria B. Rasotto

2001-01-01

341

A role for acidophilic granulocytes in the testis of the gilthead seabream (Sparus aurata L., Teleostei)  

Microsoft Academic Search

In mammals, a complex interaction between the immune and the reproductive systems has been described, in which testicular immune cells produce cytokines and growth factors which modulate gonad functions, while specific gonad cells influence the immune response in this organ. In this study we describe the presence of acidophilic granulocytes in the testis of the hermaphrodite teleost fish gilthead seabream

E Chaves-Pozo; P Pelegrín; V Mulero; J Meseguer; A García Ayala

2003-01-01

342

The biology of the panga, Pterogymnus laniarius (Teleostei: Sparidae), on the Agulhas Bank, South Africa  

Microsoft Academic Search

Aspects of the biology of the panga, Pterogymnus laniarius, a commercially important endemic southern African, demersal sparid fish species, are described from material collected monthly between February 1994 and July 1995 on the Agulhas Bank, South Africa. Growth studies based on sectioned sagittal otoliths revealed that the panga is relatively slow growing with ages of 16 years being recorded. Growth

Anthony J. Booth; Colin D. Buxton

1997-01-01

343

Modifications of the reproductive complex and implications for the reproductive biology of Gobiodon oculolineatus (Teleostei: Gobiidae)  

Microsoft Academic Search

The reproductive anatomy of gobiid fishes (Family Gobiidae) exhibits remarkable morphological diversity and complexity. However,\\u000a there has been little in the way of detailed anatomical descriptions of species-specific reproductive anatomy among gobiid\\u000a fishes that could be used to generate hypotheses of homology. Consequently, identifying valid reproductive synapomorphies\\u000a among extant gobiid lineages remains problematic. Gobiodon oculolineatus, an obligate coral-dwelling fish, exhibits

Kathleen S. Cole

2009-01-01

344

New Teleostei from the Agua Nueva Formation (Turonian), Vallecillo (NE Mexico)  

Microsoft Academic Search

A new genus and new species of an ichthyodectiform fish, a new species of the pachyrizodontid Goulmimichthys, as well as specimens of Araripichthys sp. are described from the Agua Nueva Formation (Turonian) of Vallecillo, State of Nuevo León, NE Mexico. The ichthyodectiform fish shows a combination of characters from different families, warranting the creation of a new genus and questioning

Alberto Blanco; Lionel Cavin

2003-01-01

345

Differentiated ZZ/ZW sex chromosomes in Apareiodon ibitiensis (Teleostei, Parodontidae): cytotaxonomy and biogeography.  

PubMed

Conventional and molecular chromosomal analyses were carried out on three populations of Apareiodon ibitiensis sampled from the hydrographic basins of the São Francisco River and Upper Paraná River (Brazil). The results reveal a conserved diploid number (2n = 54 chromosomes), a karyotype formula consisting of 50 m-sm + 4st and a ZZ/ZW sex chromosome system that has not been previously identified for the species. C-banding analysis with propidium iodide staining revealed centromeric and terminal bands located in the chromosomes of the specimens from the three populations and allowed the identification of heteromorphism of heterochromatin regions in the Z and W chromosomes. The number of 18S sites located through fluorescent in situ hybridization (FISH) varied between the populations of the São Francisco and Upper Paraná Rivers. The location of 5S rDNA sites proved comparable in one pair of metacentric chromosomes. Thus, the present study proposes a ZZ/ZW sex chromosome system for A. ibitiensis among the Parodontidae, and a hypothesis is presented regarding possible W chromosome differentiation stages in this species through DNA accumulation, showing geographical variations for this characteristic, possibly as a consequence of geographical reproductive isolation. PMID:20738689

Bellafronte, E; Vicari, M R; Artoni, R F; Margarido, V P; Moreira-Filho, O

2009-12-01

346

Osteology of Paedocypris, a miniature and highly developmentally truncated fish (Teleostei: Ostariophysi: Cyprinidae).  

PubMed

Species of the cyprinid genus Paedocypris are among the smallest and most developmentally truncated fishes and vertebrates. Our analysis of their skeletal structure reveals a puzzling combination of extreme developmental truncation and an increased morphological complexity in sexually dimorphic characters. The skeleton of Paedocypris is characterized by reduction and loss and resembles in many aspects that of a larval/early juvenile stage of its close relatives. We found 61 characters that have been affected by developmental truncation. A comparison with the skeletal development of a close relative, the zebrafish Danio rerio, demonstrates that the majority of the absent bones or skeletal structures in Paedocypris are those that appear late in the ossification trajectory of the zebrafish. Thus, their absence in Paedocypris seems to be due to the simple developmental truncation of terminal stages in the ossification sequence. Our study of the sexually dimorphic structures in Paedocypris demonstrates that predominantly the male exhibits the more complex state. In relation to the female, male Paedocypris uniquely possess a cleithrum with a pointed posterior process that covers the scapula laterally, and a more medially situated posterior flange that contacts the dorsal area of the coracoid; a massive and heavily ossified uppermost pectoral radial tightly bound to the scapula; thickened and enlarged three uppermost pectoral-fin rays; a large triangular, dorsolaterally directed process on the outer arm of the massive os suspensorium; and a enlarged and shovel-like anterodorsally directed basipterygium; and a hypertrophied first pelvic-fin ray with additional anterior flanges that support keratinized pads of skin. Female Paedocypris show only one structure that is better developed than in males: the first proximal-middle radial and the anteriormost fin ray of the dorsal fin are more massive and more heavily ossified. Although the function and biological role of these dimorphisms is still unknown, we hypothesize that they are related to a special reproductive behavior. Paedocypris is a prime example for the recent claim that miniaturization among cyprinids is associated with evolutionary novelty only in developmentally truncated miniatures and not in proportioned dwarfs. Paedocypris offers a strong challenge to Schindleria as the most extreme example of developmental truncation known among fishes. We highlight the difficulties that developmentally truncated taxa frequently pose to the resolution of their phylogenetic position and propose an approach to overcome this problem. Our phylogenetic comparison to determine the systematic position of Paedocypris among cyprinids reveals that it shares not only a number of unique absences, but also highly unusual progressive characters with Sundadanio and Danionella, two other Asian miniature cyprinids. We hypothesize that the three genera form a monophyletic group. We further found that Paedocypris and Danionella share a number of uniquely derived characters pointing to a sister group relationship of the two. PMID:19107939

Britz, R; Conway, K W

2009-04-01

347

Genetic population structure of sympatric and allopatric populations of Baltic ciscoes (Coregonus albula complex, Teleostei, Coregonidae)  

PubMed Central

Background Teleost fishes of the Coregonidae are good model systems for studying postglacial evolution, adaptive radiation and ecological speciation. Of particular interest is whether the repeated occurrence of sympatric species pairs results from in-situ divergence from a single lineage or from multiple invasions of one or more different lineages. Here, we analysed the genetic structure of Baltic ciscoes (Coregonus albula complex), examining 271 individuals from 8 lakes in northern Germany using 1244 polymorphic AFLP loci. Six lakes had only one population of C. albula while the remaining two lakes had C. albula as well as a sympatric species (C. lucinensis or C. fontanae). Results AFLP demonstrated a significant population structure (Bayesian ?B = 0.22). Lower differentiation between allopatric (?B = 0.028) than sympatric (0.063-0.083) populations contradicts the hypothesis of a sympatric origin of taxa, and there was little evidence for stocking or ongoing hybridization. Genome scans found only three loci that appeared to be under selection in both sympatric population pairs, suggesting a low probability of similar mechanisms of ecological segregation. However, removal of all non-neutral loci decreased the genetic distance between sympatric pairs, suggesting recent adaptive divergence at a few loci. Sympatric pairs in the two lakes were genetically distinct from the six other C. albula populations, suggesting introgression from another lineage may have influenced these two lakes. This was supported by an analysis of isolation-by-distance, where the drift-gene flow equilibrium observed among allopatric populations was disrupted when the sympatric pairs were included. Conclusions While the population genetic data alone can not unambiguously uncover the mode of speciation, our data indicate that multiple lineages may be responsible for the complex patterns typically observed in Coregonus. Relative differences within and among lakes raises the possibility that multiple lineages may be present in northern Germany, thus understanding the postglacial evolution and speciation in the C. albula complex requires a large-scale phylogenetic analysis of several potential founder lineages. PMID:20350300

2010-01-01

348

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

PubMed

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

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

2014-11-01

349

A study of the eastern Johnny Darter, Etheostoma olmstedi storer (teleostei, percidae)  

Microsoft Academic Search

The subgenusBoleosoma is herein restricted to include:Etheostoma olmstedi, E. nigrum, E. perlongum, E. longimanum, andE. podostemone. Members of the subgenus lack nuptial tubercles, the males darken during the breeding season and females have bilobed genital\\u000a papillae. The following three species are excluded from the subgenusBoleosoma: Etheostoma jessiae andE. stigmaeum, males having elongate genital papillae (considerably shortened in males ofBoleosoma) and

Charles F. Cole

1967-01-01

350

Mitogenomic circumscription of a novel percomorph fish clade mainly comprising "Syngnathoidei" (Teleostei).  

PubMed

Percomorpha, comprising about 60% of modern teleost fishes, has been described as the "(unresolved) bush at the top" of the tree, with its intrarelationships still being ambiguous owing to huge diversity (>15,000 species). Recent molecular phylogenetic studies based on extensive taxon and character sampling, however, have revealed a number of unexpected clades of Percomorpha, and one of which is composed of Syngnathoidei (seahorses, pipefishes, and their relatives) plus several groups distributed across three different orders. To circumscribe the clade more definitely, we sampled several candidate taxa with reference to the previous studies and newly determined whole mitochondrial genome (mitogenome) sequences for 16 percomorph species across syngnathoids, dactylopterids, and their putatively closely-related fishes (Mullidae, Callionymoidei, Malacanthidae). Unambiguously aligned sequences (13,872 bp) from those 16 species plus 78 percomorphs and two outgroups (total 96 species) were subjected to partitioned Bayesian and maximum likelihood analyses. The resulting trees revealed a highly supported clade comprising seven families in Syngnathoidei (Gasterosteiformes), Dactylopteridae (Scorpaeniformes), Mullidae in Percoidei and two families in Callionymoidei (Perciformes). We herein proposed to call this clade "Syngnathiformes" following the latest nuclear DNA studies with some revisions on the included families. PMID:24680775

Song, Ha Yeun; Mabuchi, Kohji; Satoh, Takashi P; Moore, Jon A; Yamanoue, Yusuke; Miya, Masaki; Nishida, Mutsumi

2014-06-01

351

FIG. S1.--Maximum parsimony phylogenetic relationships among New Zealand galaxiids based on partial cytochrome b and 16SrRNA mitochondrial DNA sequences  

E-print Network

for the sister-relationship between Galaxias `southern' from the Mararoa and conspecifics in the Oreti of the other Galaxias spp that appear next-most closely related (i.e. G. vulgaris, G. sp. D, G. `northern', G

Fletcher, David

352

Biological Journal of the Linnean Society, 2006, 87, 6982. With 6 figures 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 87, 6982 69  

E-print Network

@yahoo.com Latitudinal and ecological correlates of morphological variation in Galaxias platei (Pisces, Galaxiidae individual Galaxias platei (N = 380) col- lected from 20 postglacial lakes in the southern Andes. The lakes

Ruzzante, Daniel E.

353

Molecular Ecology (2008) 17, 22342244 doi: 10.1111/j.1365-294X.2008.03738.x 2008 The Authors  

E-print Network

years ago). The colder-water inhabitant, Galaxias platei, underwent a strong bottleneck during the LGM ecological traits and distributions led to distinctive responses. Keywords: Bayesian skyline plots, Galaxias

Ruzzante, Daniel E.

354

IAUColloquium194-CompactBinariesintheGalaxyandBeyond(Copyright2004:IA,UNAM) Editors:G.Tovmassian&E.Sion  

E-print Network

un resumen de las observaciones claves de fuentes de rayos X realizadas recientemente en galaxias de tipos tempranos. T´ipicamente, alrededor de la mitad de las binarias de rayos X en galaxias de tipos

Puzia, Thomas H.

355

Fragments of a Late Modernity: José Angel Valente and Samuel Beckett  

E-print Network

libro futuro. Barcelona: Galaxia Gutenberg, Círculo de Lectores, 2000. ———. La experiencia abisal. Barcelona: Galaxia Gutenberg, 2004. ———. Las palabras de la tribu. Madrid: Siglo XXI, 1971. ———. Material memoria (1979-1989). Madrid: Alianza, 1992...

Mayhew, Jonathan

2007-01-01

356

Thursday, March 15, 2007 MARS SURFACE PROCESS AND EVOLUTION  

E-print Network

.* Skinner L. A. Kargel J. S. Re-Assessment of Hydrovolcanism-based Resurfacing Within the Galaxias Fossae of the Galaxias Fossae region and speculate it evolved through debris intrusion into transient ice-rich mantles

Rathbun, Julie A.

357

Astrofsica Extragalctica y Cosmologa II Mayo-Julio 2007  

E-print Network

galaxias y estructura a gran escala 1.1 Cúmulos cercanos: Virgo y Coma 1.2 Criterios de selección 1 las galaxias en el cúmulo: relación morfología- densidad, función de luminosidad, evolución II. Materia oscura 2.1 Materia oscura en galaxias 2.2 Materia oscura en cúmulos de galaxias 2.3 Propiedades y

Aretxaga, Itziar

358

Astrofsica Extragalctica y Cosmologa. Problemas y preguntas clave I.  

E-print Network

relación liga al corrimiento al rojo con el factor de escala del universo. 7. Dadas 3 galaxias A factor 2 d. La galaxia Andrómeda está un factor 2 más alejada e. La galaxia Andrómeda está un factor distancia Vía Láctea ­ Andrómeda es constante a lo largo del tiempo h. Las distancias entre las galaxias en

Aretxaga, Itziar

359

Journal of Fish Biology (2002) 61, 138156 doi:10.1006/jfbi.2002.2027, available online at http://www.idealibrary.com on  

E-print Network

://www.idealibrary.com on Predator associated morphology in Galaxias platei in Patagonian lakes D. MILANO*§, V. E. CUSSAC*, P. J, Silkeborg, Denmark (Received 24 July 2001, Accepted 27 May 2002) Among 158 Galaxias platei individuals: morphological variation; piscivory; feeding; Galaxias platei; Andean lakes. INTRODUCTION Intraspecific

Ruzzante, Daniel E.

360

Copyright2009:InstitutodeAstronoma,UniversidadNacionalAutnomadeMxico Revista Mexicana de Astronomia y Astrofisica, 45, 261272 (2009)  

E-print Network

´on de 29 galaxias disponibles en la literatura, creando la primera base de datos del DIG (DI- GEDA ´unicamente cuando consideramos galaxias por separado. Finalmente, encontramos que las regiones clasificadas como DIG en galaxias Irr parecen tener un comportamiento m´as cercano al de las regiones H II que al

Morisset, Christophe

361

To appear in \\Galaxy Evolution: Theory and Observations (2002)" RevMexAA(SC) THE REDSHIFT DISTRIBUTION OF SUB-MM GALAXIES  

E-print Network

fotom#19;etricos de galaxias seleccionadas en bandas submilim#19;etricas (SCUBA) y milim#19;etricas corrimientos al rojo de galaxias seleccionadas en campos amplios podr#19;#16;a tener una larga cola. Se espera% de las galaxias tienen colores que son consistentes con z > 4. ABSTRACT Ground-based sub-mm (SCUBA

Aretxaga, Itziar

362

VOLUME SIXTEEN MAY-JUNE 2002  

E-print Network

GALAXIAS ­ T.A. Raadik & R.H. Kuiter AUSTRALIAN LUNGFISH ­ Jean Joss FLOATING-LEAF PONDWEED ­ Nick;830 Kosciuszko Galaxias: a story of confusion and imminent peril. Tarmo A. Raadik* & Rudie H. Kuiter** Confusion in March the same year, naming the species Galaxias findlayi, dedicating it to the collector

Canberra, University of

363

COMUNICADO DE PRENSA EL GENERADOR DE IMGENES DEL FONDO DEL UNIVERSO  

E-print Network

anterior a la existencia de las estrellas y las galaxias, muestran por primera vez las semillas a partir de las cuales se formaron los cúmulos de galaxias. Las observaciones se realizaron mediante el Generador y las galaxias. Las pequeñas fluctuaciones de densidad de esa época se desarrollaron bajo la

Readhead, Anthony

364

New Zealand Natural Sciences (2002) 27: 1-14 Estimating the abundance of banded kokopu  

E-print Network

New Zealand Natural Sciences (2002) 27: 1-14 Estimating the abundance of banded kokopu (Galaxias (Galaxias fasciatus Gray) in small streams has usually been determined by the labour intensive and invasive for visual counts of banded kokopu by spotlight in summer months. Keywords: banded kokopu - Galaxias

Waikato, University of

365

Copyright2009:InstitutodeAstronoma,UniversidadNacionalAutnomadeMxico Revista Mexicana de Astronomia y Astrofisica, 45, 127137 (2009)  

E-print Network

diferentes galaxias nos permite obtener importantes l´imites para los modelos de evoluci´on qu´imica en estos sistemas. Tenemos un programa a largo plazo para derivar abundancias en las galaxias del Grupo Local, en galaxia y otras del Grupo Local. Como resultado de nuestras observaciones, hemos obtenido una gran base de

Maciel, Walter Junqueira

366

Molecular Ecology (2008) 17, 50495061 doi: 10.1111/j.1365-294X.2008.03987.x 2008 The Authors  

E-print Network

by the phylogeographical signal of Galaxias platei in Patagonia TYLER S. ZEMLAK,* EVELYN M. HABIT, SANDRA J. WALDE,* MIGUEL at two mitochondrial (control region, COI) regions from 212 individuals of Galaxias platei (Pisces Patagonia. Keywords: drainage reversal, Galaxias platei, orogeny, phylogeography, Pleistocene glacial cycles

Ruzzante, Daniel E.

367

International Journal of PIXE, Vol. 15, Nos. 3 & 4 (2005) 9Fh01 World Scientitlc  

E-print Network

for the conservation of diadromous fish. The genus Galaxias (Galaxiidae: Osmeriformes) contains five diadromous species with a number of diadromous representatives are Galaxias (Osmeriformes: Galaxiidae) and ' Correspondenceto: Dr to scale vertical faces that are covered by a film of water,' and penetrate far Koaro (Galaxias brevipinnis

Waikato, University of

368

To appear in \\Galaxy Evolution: Theory and Observations (2002)" RevMexAA(SC) DEEP: NEW SURVEYS OF DISTANT FIELD GALAXIES  

E-print Network

dos fases (DEEP1, DEEP2) con el objectivo de caracterizar las propiedades de galaxias lejanas del la cinem#19;atica interna de galaxias, y imagenes HST. Con el DEEP, aspiramos caracterizar la formac#19;#16;on y evoluc#19;#16;on de galaxias, mapear las estructuras de larga escala lejanas, y imponer

369

En expansin acelerada: el Premio Nobel de Fsica 2011  

E-print Network

Hubble había acumulado observaciones de 24 galaxias que le permitieron cambiar nuestra concepción del Universo. Las galaxias son sistemas autogravitan- tes donde se forman y evolucionan las estrellas, en interacción con el gas interestelar. Nosotros somos parte de una galaxia constituida por 200,000 millo- nes de

Rodriguez, Luis F.

370

DOI 10.1007/s10211-006-0012-8 ORIGINAL ARTICLE  

E-print Network

complex (Teleostei, Cyprinidae): an example of interplay between female choice and ecological pressures. Keywords Cyprinidae . Female choice . Sexual selection . Reproductive behaviour . Courting displays

371

Mercury in the biotic compartments of Northwest Patagonia lakes, Argentina.  

PubMed

We report on total mercury (THg) concentrations in the principal components of food webs of selected Northern Patagonia Andean Range ultraoligotrophic lakes, Argentina. The THg contents were determined using Instrumental Neutron Activation Analysis in muscle and liver of four fish species occupying the higher trophic positions (the introduced Salmo trutta, Oncorhynchus mykiss and Salvelinus fontinalis, and the native Percichthys trucha) accounted for eight lakes belonging to Nahuel Huapi and Los Alerces National Parks. We studied the food web components of both the West and East branches of Lake Moreno, including benthic primary producers such as biofilm, mosses, and macrophytes, three plankton fractions, fish, riparian tree leaves, and benthic invertebrates, namely decapods, molluscs, insect larvae, leeches, oligochaetes, and amphipods. Mercury concentrations in fish muscle varied in a wide range, from less than 0.05 to 4 ?g g(-1) dry weight (DW), without a distribution pattern among species but showing higher values for P. trucha and S. fontinalis, particularly in Lake Moreno. The THg contents of the food web components of Lake Moreno varied within 4 orders of magnitude, with the lower values ranging from 0.01 to 0.5 ?g g(-1) DW in tree leaves, some macrophytes, juvenile salmonids or benthic macroinvertebrates, and reaching concentrations over 200 ?g g(-1) DW in the plankton. Juvenile Galaxias maculatus caught in the pelagic area presented the highest THg contents of all fish sampled, reaching 10 ?g g(-1) DW, contents that could be associated with the high THg concentrations in plankton since it is their main food source. Although Lake Moreno is a system without local point sources of contamination, situated in a protected area, some benthic organisms presented high THg contents when compared with those from polluted ecosystems. PMID:21421254

Rizzo, A; Arcagni, M; Arribére, M A; Bubach, D; Guevara, S Ribeiro

2011-06-01

372

Separating natural responses from experimental artefacts: habitat selection by a diadromous fish species using odours from conspecifics and natural stream water.  

PubMed

Animals use sensory stimuli to assess and select habitats, mates and food as well as to communicate with other individuals. One way they do this is to use olfaction, whereby they identify and respond to chemical cues. All organisms release odours, which mix with other chemical substances and ambient environmental conditions. The result is that animals are frequently immersed in a complex, highly dynamic sensory environment where they must identify and respond to only some of the potential stimuli they encounter in the face of significant levels of background noise. Understanding how organisms respond to different chemical cues is therefore dependent on knowing how these responses might be influenced by potential interactions with other stimuli. To test this, we examined whether the diadromous fish Galaxias maculatus was attracted to conspecific odours and whether this response differed when cues were offered in an artificial environment lacking other potential chemical stimuli (tap water) or a more natural background environment (stream water). We found that (1) fish responded to both natural stream water odours and those from conspecifics but the response to the latter was stronger; (2) the attraction to conspecific odours was stronger in tap water than in stream water, which indicates the importance of these odours may be overestimated when they are offered in artificial media. We also conducted a brief literature review, which confirmed that artificial media are commonly used in experiments and that the background environment is often not considered. Our results show that future research testing the responses of organisms to auditory, olfactory and visual cues should carefully consider the context in which cues are presented. Without doing so, such studies may inaccurately assess the importance of sensory cues in natural situations in the wild. PMID:19139923

Hale, Robin; Swearer, Stephen E; Downes, Barbara J

2009-03-01

373

The impacts of stress on sodium metabolism and copper accumulation in a freshwater fish.  

PubMed

In freshwater fish, stress can often result in significant modifications to Na(+) metabolism and may be an important aspect to consider in conservation efforts; as maintaining ion balance is critical to survival and ion transport is also a key determinant of metal toxicity. In order to better quantify the response of stress, Na(+) influx, Na(+) efflux, and copper accumulation were measured as a result of handling stress in inanga (Galaxias maculatus). This species is a culturally and economically important fish in New Zealand as one of the major species in the local 'whitebait' fishery. Na(+) influx rates in inanga were found to be 2-3 times greater after handling than in 'recovered' fish, and Na(+) efflux rates increased in the range of 5-6 times. Both influx and efflux rates quickly returned to resting levels within 24h. Increases in Na(+) efflux were strongly correlated with opercular beat frequency. This suggests an increas in ventilation, and subsequent enhanced diffusive loss of Na(+), as the mechanism of increased Na(+) efflux. Total body copper levels were also measured under similar treatments. Fish had significantly higher levels of copper directly after handling than following a 24h recovery; likely due to a shared Na(+)/copper uptake pathway. As accumulation is linked to toxicity, fish exposed to elevated copper levels in stressful environments will consequently be more at risk to metal toxicity. In a natural environment, stress can come from many different sources; among which, anthropogenic disturbances can often be a cause. Given that inanga must migrate through metal-contaminated coastal regions to reach breeding habitats, they will be exposed to toxicants under conditions where perfusion and ventilation of the gill is increased. As such, ion loss would be exacerbated, leading to an enhanced compensatory ion uptake and an increase in accumulation of ion-mimicking toxicants such as copper, exacerbating toxicity. This is a concern as conservation efforts in more disruptive environments may not be adequately protected. PMID:24374847

Harley, Rachel A; Glover, Chris N

2014-02-01

374

Synergistic interactions within disturbed habitats between temperature, relative humidity and UVB radiation on egg survival in a diadromous fish.  

PubMed

Anthropogenic impacts, including urbanization, deforestation, farming, and livestock grazing have altered riparian margins worldwide. One effect of changes to riparian vegetation is that the ground-level light, temperature, and humidity environment has also been altered. Galaxias maculatus, one of the most widely distributed fishes of the southern hemisphere, lays eggs almost exclusively beneath riparian vegetation in tidally influenced reaches of rivers. We hypothesized that the survival of these eggs is greatly affected by the micro-environment afforded by vegetation, particularly relating to temperature, humidity and UVB radiation. We experimentally reduced riparian vegetation height and altered shading characteristics, tracked egg survival, and used small ground-level temperature, humidity and UVB sensors to relate survival to ground-level effects around egg masses. The ground-level physical environment was markedly different from the surrounding ambient conditions. Tall dense riparian vegetation modified ambient conditions to produce a buffered temperature regime with constant high relative humidity, generally above 90%, and negligible UVB radiation at ground-level. Where vegetation height was reduced, frequent high temperatures, low humidity, and high UVB irradiances reduced egg survival by up to 95%. Temperature effects on egg survival were probably indirect, through reduced humidity, because developing eggs are known to survive in a wide range of temperatures. In this study, it was remarkable how such small variations in relatively small sites could have such a large effect on egg survival. It appears that modifications to riparian vegetation and the associated changes in the physical conditions of egg laying sites are major mechanisms affecting egg survival. The impacts associated with vegetational changes through human-induced disturbances are complex yet potentially devastating. These effects are particularly important because they affect a very small portion of habitat that is required to complete the life history of a species, despite the wide distribution of adults and juveniles across aquatic and marine environments. PMID:21931680

Hickford, Michael J H; Schiel, David R

2011-01-01

375

Synergistic Interactions within Disturbed Habitats between Temperature, Relative Humidity and UVB Radiation on Egg Survival in a Diadromous Fish  

PubMed Central

Anthropogenic impacts, including urbanization, deforestation, farming, and livestock grazing have altered riparian margins worldwide. One effect of changes to riparian vegetation is that the ground-level light, temperature, and humidity environment has also been altered. Galaxias maculatus, one of the most widely distributed fishes of the southern hemisphere, lays eggs almost exclusively beneath riparian vegetation in tidally influenced reaches of rivers. We hypothesized that the survival of these eggs is greatly affected by the micro-environment afforded by vegetation, particularly relating to temperature, humidity and UVB radiation. We experimentally reduced riparian vegetation height and altered shading characteristics, tracked egg survival, and used small ground-level temperature, humidity and UVB sensors to relate survival to ground-level effects around egg masses. The ground-level physical environment was markedly different from the surrounding ambient conditions. Tall dense riparian vegetation modified ambient conditions to produce a buffered temperature regime with constant high relative humidity, generally above 90%, and negligible UVB radiation at ground-level. Where vegetation height was reduced, frequent high temperatures, low humidity, and high UVB irradiances reduced egg survival by up to 95%. Temperature effects on egg survival were probably indirect, through reduced humidity, because developing eggs are known to survive in a wide range of temperatures. In this study, it was remarkable how such small variations in relatively small sites could have such a large effect on egg survival. It appears that modifications to riparian vegetation and the associated changes in the physical conditions of egg laying sites are major mechanisms affecting egg survival. The impacts associated with vegetational changes through human-induced disturbances are complex yet potentially devastating. These effects are particularly important because they affect a very small portion of habitat that is required to complete the life history of a species, despite the wide distribution of adults and juveniles across aquatic and marine environments. PMID:21931680

Hickford, Michael J. H.; Schiel, David R.

2011-01-01

376

Population sinks resulting from degraded habitats of an obligate life-history pathway.  

PubMed

Many species traverse multiple habitats across ecosystems to complete their life histories. Degradation of critical, life stage-specific habitats can therefore lead to population bottlenecks and demographic deficits in sub-populations. The riparian zone of waterways is one of the most impacted areas of the coastal zone because of urbanisation, deforestation, farming and livestock grazing. We hypothesised that sink populations can result from alterations of habitats critical to the early life stages of diadromous fish that use this zone, and tested this with field-based sampling and experiments. We found that for Galaxias maculatus, one of the most widely distributed fishes of the southern hemisphere, obligate riparian spawning habitat was very limited and highly vulnerable to disturbance across 14 rivers in New Zealand. Eggs were laid only during spring tides, in the highest tidally influenced vegetation of waterways. Egg survival increased to >90% when laid in three riparian plant species and where stem densities were great enough to prevent desiccation, compared to no survival where vegetation was comprised of other species or was less dense. Experimental exclusion of livestock, one of the major sources of riparian degradation in rural waterways, resulted in quick regeneration, a tenfold increase in egg laying by fish and a threefold increase in survival, compared to adjacent controls. Overall, there was an inverse relationship between river size and egg production. Some of the largest rivers had little or no spawning habitat and very little egg production, effectively becoming sink populations despite supporting large adult populations, whereas some of the smallest pristine streams produced millions of eggs. We demonstrate that even a wide-ranging species with many robust adult populations can be compromised if a stage-specific habitat required to complete a life history is degraded by localised or more diffuse impacts. PMID:21076966

Hickford, Michael J H; Schiel, David R

2011-05-01

377

Modeling prey consumption by native and non-native piscivorous fishes: implications for competition and impacts on shared prey in an ultraoligotrophic lake in Patagonia  

USGS Publications Warehouse

We examined trophic interactions of the nonnative salmonids Rainbow Trout Oncorhynchus mykiss, Brown Trout Salmo trutta, and Brook Trout Salvelinus fontinalisand the main native predator Creole Perch Percichthys trucha in Lake Nahuel Huapi (Patagonia, Argentina) to determine the relative impact of each predator on their forage base and to evaluate the potential vulnerability of each predator to competitive impacts by the others. Using bioenergetics simulations, we demonstrated the overall importance of galaxiids and decapods to the energy budgets of nonnative salmonids and Creole Perch. Introduced salmonids, especially Rainbow Trout, exerted considerably heavier predatory demands on shared resources than did the native Creole Perch on both a per capita basis and in terms of relative population impacts. Rainbow Trout consumed higher quantities and a wider size range of Small Puyen (also known as Inanga) Galaxias maculatus than the other predators, including early pelagic life stages of that prey; as such, this represents an additional source of mortality for the vulnerable early life stages of Small Puyen before and during their transition from pelagic to benthic habitats. All predators were generally feeding at high feeding rates (above 40% of their maximum physiological rates), suggesting that competition for prey does not currently limit either Creole Perch or the salmonids in this lake. This study highlights the importance of keystone prey for the coexistence of native species with nonnative top predators. It provides new quantitative and qualitative evidence of the high predation pressure exerted on Small Puyen, the keystone prey species, during the larval to juvenile transition from pelagic to littoral-benthic habitat in Patagonian lakes. This study also emphasizes the importance of monitoring salmonid and Creole Perch population dynamics in order to detect signs of potential impacts through competition and shows the need to carefully consider the rationale behind any additional trout stocking.

Juncos, Romina; Beauchamp, David A.; Viglianoc, Pablo H.

2013-01-01

378

Myxobolus groenlandicus n. sp. (Myxozoa) distorting skeletal structures and musculature of Greenland halibut Reinhardtius hippoglossoides (Teleostei: Pleuronectidae).  

PubMed

A specimen of Greenland halibut Reinhardtius hippoglossoides (Walbaum, 1792) caught on the west coast of Greenland (Qasigiannguit) was found to possess serious pathological changes in the body musculature. A series of cartilaginous cylindrical structures organized symmetrically at the position of the proximal pterygiophores had changed the musculature and produced irreversible distortions (cavities and holes) in the fillet of the processed fish, leaving it with no value for the industry. Histopathological investigation showed that these structures consisted of hypertrophic cartilage containing numerous myxospore-producing plasmodia. Morphometric and molecular analyses of the parasites showed that both spore morphology and rDNA sequences complied with characteristics of the genus Myxobolus, but no full affiliation with a known species could be found. The parasite is a previously undescribed species, and the name Myxobolus groenlandicus n. sp. is assigned to this new myxobolid. PMID:22436461

Buchmann, Kurt; Skovgaard, Alf; Kania, Per W

2012-03-20

379

[A comparative study of sperm postspawning destruction in flatfishes Hippoglossoides (Cleisthenes) herzensteini and Hippoglossoides dubius (Teleostei, Pleuronectidae)].  

PubMed

Ultrastructural aspects of sperm destruction patterns were offered as additional cytological parameters for evaluation of the genus affinity of flatfishes Hippoglossoides dubius and Cleisthenes herzensteini. At the beginning of spermatozoan destruction, cell membrane in both species was found swollen, besides, discontinuity of membranes was observed, and membraneous parts were seen separating from sparmatozoa. We observed the ability of separated membraneous parts to aggregate to twisting conglomerates that wind round the objects of destruction. In H. dubius the membraneous conglomerates wound round spermatozoa, and after that such spermatozoa were phagocyted by follicular cells. In C. herzensteini, the membraneous conglomerates grasped the particles of destructed spermatozoa: the formed residual bodies were collected in the gonad lumen but not phagocyted by follicular cells. The expressiveness of the differences found in the pattern of sperm destruction is so considerable that, in the authors' opinion, these data are to supplement a list of criteria making reasonable reconsideration of the taxonomic status of C. herzensteini: its belonging to the genus Hippoglossoides, and establishing of the genus Cleisthenes as an independent rank. PMID:15598016

Reunov, A A; Neznanova, S Iu; Ivankov, V N

2004-01-01

380

Parvicapsula bicornis n. sp. and P. limandae n. sp. (Myxozoa, Parvicapsulidae) in Pleuronectidae (Teleostei, Heterosomata) from Denmark.  

PubMed

Two species of Parvicapsula were found in the kidney tubules and the urinary bladder of 2 pleuronectid fish from the northern Oresund, Denmark. The coelozoic, spherical, disporic trophozoites of both species are 10 to 12 pm in diameter. The myxospores of both species are elongate, asymmetrical and slightly curved, and have spherical polar capsules. Parvicapsula bicornis n. sp. (6-8 x 5-6 microm, polar capsule 2.5 microm in diameter) occurs in Pleuronectes platessa. The polar capsules of P. bicornis are arranged symmetrically on either side of the longitudinal axis and its spores differ from other species of Parvicapsula in having two 2-3 microm long posterior processes of different length. Parvicapsula limandae n. sp. (8-11 x 4-5 pm, polar capsule 1.6 microm in diameter) is found in Limanda limanda. The polar capsules are arranged along the longitudinal axis. It differs from Parvicapsula unicornis Kabata, 1962, recorded from L. limanda, in the arrangement of the polar capsules and in the absence of a posterior horn-like projection. The phylogenetic relationship between P. bicornis n. sp., P. limandae n. sp. and other Parvicapsula spp. was examined with their partial small subunit rDNA (SSU rDNA) sequences. P. limandae n. sp. and P. asymmetrica appear to be closely related, while P. bicornis n. sp. and P. minibicornis are the most divergent members of the genus. PMID:17760385

Køie, Marianne; Karlsbakk, Egil; Nylund, Are

2007-06-29

381

Trilosporoides platessae gen. et sp. n. (Myxozoa: Multivalvulida) in the plaice Pleuronectes platessa (Teleostei: Pleuronectidae) from Denmark.  

PubMed

A new myxosporean species, Trilosporoides platessae gen. et sp. n. (Multivalvulida), is described from the gallbladder of the plaice Pleuronectes platessa L. (Pleuronectidae) from Denmark. The myxospore of T. platessae is conical in side view, with a 24 microm long, pointed posterior projection. In apical view, the myxospore (diameter 9.4 microm) is round, trilobed and with three spherical polar capsules arranged peripherally, equidistant and opening peripherally through protruding tips. The polar capsules are of different sizes, one often larger than the others (diameter 3.3 microm vs. 2.5 microm). Apart from the long posterior projection, the myxospore of T. platessae differs from those of the three known species of Trilospora Noble, 1959 and from all genera within the order Multivalvulida Shulman, 1959 in the arrangement of the polar capsules. Trilosporoides platessae may temporarily be placed in the vicinity of the Trilosporidae. PMID:16405293

Køie, Marianne

2005-11-01

382

Cytochrome b ( Cyt-b ) gene sequence analysis in six flatfish species (Teleostei, Pleuronectidae), with phylogenetic and taxonomic insights  

Microsoft Academic Search

Mitochondrial DNA (mtDNA) at Cyt-b gene region was sequenced for six flatfish species (in total nine sequences of at least 1,117 bp) from the Far East of Russia\\u000a and compared with other sequences of Pleuronectiformes comprising altogether 34 species and 3 outgroup species (Perciformes).\\u000a Analysis of the protein-coding Cyt-b gene revealed a statistically substantiated bias in (T + C):(A + G) content, supporting earlier findings.

Y. P. Kartavtsev; T.-J. Park; K. A. Vinnikov; V. N. Ivankov; S. N. Sharina; J.-S. Lee

2007-01-01

383

Ultrastructural Study of Relationships between Germinal Bodies and Mitochondria in Apostichopus japonicus (Echinodermata: Holothuroidea) and Pleuronectes asper (Teleostei: Pleuronectidae)  

Microsoft Academic Search

The relationships between germinal bodies and mitochondria were studied in the holothurian Apostichopus japonicus and the flounder Pleuronectes asper using TEM. In the gonial cells of both species the mitochondria are arranged around germinal bodies and are in contact with the latter. A gradual disappearance of the outer membrane is found in the mitochondria that interact with the germinal substance.

A. A. Reunov; S. Yu. Neznanova; Ya. N. Aleksandrova; V. V. Isaeva

2004-01-01

384

Resolving Taxonomy and Historic Distribution for Conservation of Rare Great Plains Fishes: Hybognathus (Teleostei: Cyprinidae) in Eastern Colorado Basins  

Microsoft Academic Search

(brassy minnow) and Hybognathus placitus (plains minnow) have made determination of their historic distributions and conservation status unclear in eastern Colorado basins. We developed logistic regression models from morphometric measurements to predict species identity of Hybognathus collections from Colorado and adjacent counties (n 5 1154 specimens in 134 lots). A model based on orbit diameter, stan- dard length, and eye

Julie A. Scheurer; Kevin R. Bestgen; Kurt D. Fausch; S. A. Schaefer

2003-01-01

385

Triplomystus applegatei, sp. nov. (Teleostei: Ellimmichthyiformes), a rare “triple armored herring” from El Espinal Quarry (Early Cretaceous), Chiapas, southeastern Mexico  

Microsoft Academic Search

Triplomystus applegatei, sp. nov., is described as a new clupeomorph fish belonging to the order Ellimmichthyiformes, based on a single specimen collected from the Early Cretaceous (Albian) limestones of El Espinal quarry, near Ocozocuautla de Espinosa, Chiapas, southeastern Mexico. T. applegatei is differentiated from the other two species of the genus on the basis of body proportions and meristic data,

Jesús Alvarado-Ortega; Ernesto Ovalles-Damián

2008-01-01

386

Composition and structure of the parasite faunas of cod, Gadus morhua L. (Teleostei: Gadidae), in the North East Atlantic  

PubMed Central

Background Although numerous studies on parasites of the Atlantic cod, Gadus morhua L. have been conducted in the North Atlantic, comparative analyses on local cod parasite faunas are virtually lacking. The present study is based on examination of large samples of cod from six geographical areas of the North East Atlantic which yielded abundant baseline data on parasite distribution and abundance. Materials and Methods A total of 826 fish was sampled in the Baltic, Celtic, Irish and North seas, Icelandic waters and Trondheimsfjord (Norway) in 2002 (spring and autumn) and 2003 (spring). The gills and internal organs (oesophagus, stomach, intestine, pyloric caeca, liver, heart, spleen, gall bladder and gonads) were examined for macroparasites following a standardised protocol. The taxonomic consistency of the identification was ensured thorough the entire study. Results We discuss some problems in parasite identification, outline the composition of the parasite faunas in cod in the six North East Atlantic regions, provide novel data on parasite prevalence and abundance and a comparative assessment of the structure of the regional parasite faunas with respect to the higher-level taxonomic groupings, host specificity and zoogeographical distribution of the parasites. Altogether 57 different parasite forms were found including seven new host records (Diclidophora merlangi, Rhipidocotyle sp., Fellodistomum sp., Steringotrema sp., Cucullanus sp., Spinitectus sp., and Chondracanthus ornatus). The predominant groups of cod parasites were trematodes (19 species) and nematodes (13 species) including larval anisakids which comprised 58.2% of the total number of individuals. Conclusion Our study reveals relatively rich regional parasite faunas in cod from the North East Atlantic which are dominated by generalist parasites with Arcto-Boreal distribution. Further, it provides more detailed data on the distribution in the North East Atlantic of the majority of cod parasites which may serve as baselines for future studies on the effect of climate change. Based on the faunal comparisons, predictions can be made in relation to the structure and diversity of the parasite communities in the North East Atlantic regions studied. PMID:18638387

Perdiguero-Alonso, Diana; Montero, Francisco E; Raga, Juan Antonio; Kostadinova, Aneta

2008-01-01

387

Four new species of coral gobies (Teleostei: Gobiidae: Gobiodon), with comments on their relationships within the genus  

PubMed Central

Four new species of the coral-associated gobiid genus Gobiodon were discovered in the Red Sea. Although several of these species are common not only in the Red Sea but also in the Indian and western Pacific Ocean, they have not been described before. Detailed descriptions of the four species are based on morphological and molecular genetic (mitochondrial 12s and 16s rRNA) investigations. The new species, like most species of the genus, lack scales and have species-specific life colouration. Gobiodon bilineatus sp. nov. is the closest relative to G. quinquestrigatus (Valenciennes) and of G. sp. D (Munday et al.), and has five distinct, blue lines on the head as juveniles and subadults, which disappear in adults, and which are often uniformly orange-red with two distinct, vertical blue lines through each eye. Gobiodon irregularis sp. nov. has been confused with the former new species in the past, and is closely related to G. oculolineatus Wu, but is unmistakable in live colouration. Juveniles are characterised by a transparent body, red bars on the head with bluish to greyish interspaces, and irregular red lines and dots on the nape and dorsally on the body. Adults are usually uniformly brown or green-brown, with only remnants of the bars through the eye and below the orbit. Gobiodon ater sp. nov. is a small, entirely black species and can be easily confused with other black species, although it is genetically clearly distinct from G. ceramensis Bleeker and its black relatives. Gobiodon fuscoruber sp. nov. is likely to be the closest relative of G. ater sp. nov., but is uniformly reddish-brown or brown, has bright median fin margins (at least in the Red Sea), and grows considerably larger than G. ater. It has been genetically determined that G. fuscoruber sp. nov. is identical with an Indian Ocean/western Pacific species that has been called G. unicolor Castelnau by several authors. However, examination of the holotype of G. unicolor, including the original description, revealed that the type species and original description are clearly different from the species frequently called G. unicolor. The holotype resembles G. histrio (Valenciennes) and the name G. unicolor must therefore be considered a junior synonym of G. histrio. As a consequence, a new name for this species is provided. PMID:24511221

Bogorodsky, Sergey V.; Suzuki, Toshiyuki

2013-01-01

388

A fossil southern grayling, genus Prototroctes, from the Pleistocene of north?eastern New Zealand (Teleostei: Retropinnidae)  

Microsoft Academic Search

This paper reports two fossil fishes, most probably of the genus Prototroctes, from a mid?Pleistocene lake deposit in north?eastern New Zealand. These are the first known fossils of this genus, which is found only in south?eastern Australia and New Zealand.

R. M. McDowall; E. M. Kennedy; B. V. Alloway

2006-01-01

389

Review of the fossil pufferfish genus Archaeotetraodon (Teleostei, Tetraodontidae), with description of three new taxa from the Miocene of Italy  

Microsoft Academic Search

Three new species of the extinct pufferfish genus Archaeotetraodon are described from the Middle to Upper Miocene of Italy (A. bannikovi nov. sp., A. dicarloi nov. sp. and A. zafaranai nov. sp.), and compared in detail with the three previously described taxa of the genus [A. jamestyleri (Bannikov), A. winterbottomi Tyler and Bannikov and A. cerrinaferoni Carnevale and Santini], which are known, respectively, from the Miocene

Giorgio Carnevale; James C. Tyler

2010-01-01

390

Crevice spawning behavior in Dionda dichroma , with comments on the evolution of spawning modes in North American shiners (Teleostei: Cyprinidae)  

Microsoft Academic Search

The crevice spawning behavior of Diondadichroma is described for the first time, andcompared to spawning behavior in the genusCyprinella. The evolution of crevice spawningwith respect to other spawning behaviors ofNorth American shiners is examined usingexplicitly phylogenetic hypotheses for thisgroup. We present evidence that broadcastspawning is plesiomorphic and all otherspawning behaviors are independently derived. There is evidence that crevice spawning hasevolved

Richard L. Mayden; Andrew M. Simons

2002-01-01

391

Metazoan parasites of the jack mackerel Trachurus murphyi (Teleostei, Carangidae) in a latitudinal gradient from South America (Chile and Peru).  

PubMed

The metazoa parasite fauna of the jack mackerel Trachurus murphyi Nichols 1920, obtained from seven ports from a latitudinal gradient of more than 30 degrees (From Paita Peru: 05 degrees 10' S to Talcahuano, Chile 36 degrees 40' S) was quantitatively described. 21 species of metazoan parasites were recorded (Monogenea 4, Digenea 3, Cestoda 5, Acanthocephala 2, Nematoda 4, Copepoda 2, Isopoda 1). Only four parasites (Lernanthropus trachuri, Ceratothoa gaudichaudii, Corynosoma australis, Anisakis simplex) were common to the seven ports. Only twelve species reach prevalence over 5% in at least one port. Main characteristic of the parasite fauna is the sparse of adult helminthes, specifically digenean and the dominance of larval forms, at both qualitative and quantitative levels. There are not evidence of changes in the parasite community along a latitudinal gradient, but at least Anisakis simplex (larvae) shows a trend in both, prevalence and mean intensity, increasing from north to south. PMID:10511970

Oliva, M E

1999-09-01

392

Crystallaria cincotta, a new species of darter (Teleostei: Percidae) from the Elk River of the Ohio River drainage, West Virginia  

USGS Publications Warehouse

A new species of percid, Crystallaria cincotta, is described from the Cumberland, Elk, Green, and Muskingum river drainages of the Ohio River basin, USA. It differs from populations of Crystallaria asprella of the Gulf Coast, lower Mississippi River, middle Mississippi River, upper Mississippi River, and Wabash River drainages by having a reduced number of cheek scale rows restricted to the post-orbital region, a falcate margin on the pelvic fins, a preorbital blotch distinctly separate from the anterior orbital rim, and a wide mouth gape. The Elk River population is also divergent genetically from populations of the Gulf Coast, lower Mississippi River, and upper Mississippi River drainages. Crystallaria cincotta, discovered in the Elk River of the Ohio River drainage in 1980, is a rare species with the only extant population represented by 12 individuals collected from 1980-2005 from the lower 36 km section of the Elk River, West Virginia. Copyright ?? 2008 Magnolia Press.

Welsh, S. A.; Wood, R. M.

2008-01-01

393

Karyotypic diversity and evolutionary trends in the Neotropical catfish genus Hypostomus Lac?p?de, 1803 (Teleostei, Siluriformes, Loricariidae)  

PubMed Central

Abstract The family Loricariidae with 813 nominal species is one of the largest fish families of the world. Hypostominae, its more complex subfamily, was recently divided into five tribes. The tribe Hypostomini is composed of a single genus, Hypostomus Lacépède, 1803, which exhibits the largest karyotypic diversity in the family Loricariidae. With the main objective of contributing to a better understanding of the relationship and the patterns of evolution among the karyotypes of Hypostomus species, cytogenetic studies were conducted in six species of the genus from Brazil and Venezuela. The results show a great chromosome variety with diploid numbers ranging from 2n=68 to 2n=76, with a clear predominance of acrocentric chromosomes. The Ag-NORs are located in terminal position in all species analyzed. Three species have single Ag-NORs (Hypostomus albopunctatus (Regan, 1908), Hypostomus prope plecostomus (Linnaeus, 1758), and Hypostomus prope paulinus (Ihering, 1905)) and three have multiple Ag-NORs (Hypostomus ancistroides (Ihering, 1911), Hypostomus prope iheringi (Regan, 1908), and Hypostomus strigaticeps (Regan, 1908)). In the process of karyotype evolution of the group, the main type of chromosome rearrangements was possibly centric fissions, which may have been facilitated by the putative tetraploid origin of Hypostomus species. The relationship between the karyotype changes and the evolution in the genus is discussed. PMID:24260683

Alves, Anderson Luis; de Borba, Rafael Splendore; Oliveira, Claudio; Mauro Nirchio; Granado, Angel; Foresti, Fausto

2012-01-01

394

Three sympatric karyomorphs in the fish Astyanax fasciatus (Teleostei, Characidae) do not seem to hybridize in natural populations  

PubMed Central

Abstract Ninety individuals of the characid fish Astyanax fasciatus (Cuvier, 1819) were collected at Água da Madalena stream (Botucatu, São Paulo, Brazil) and analyzed for diploid chromosome number 2n and karyotype composition as well as for the chromosomal location of the 5S and 18S ribosomal DNA (rDNA). Whereas no chromosome differences were associated with sex, three different karyomorphs with diploid chromosome numbers 2n=46, 2n=48 and 2n=50 were found. No intermediate 2n numbers were discovered. The 2n=50 karyomorph showed some differences in 18S rDNA location compared to the two other karyomorphs. Finally, all specimens with the 2n=46 karyomorph showed the presence of a partly heterochromatic macro supernumerary chromosome, which was absent in all individuals with the two other karyomorphs. All these results suggest that indviduals of the three different karyomorphs are not likely to hybridize in the examined populations. Our findings strongly suggest the presence of three separate species (sensu biological species concept) easily diagnosed on the basis of differences in the diploid chromosome numbers and other chromosomal markers. PMID:24260650

Ferreira-Neto, Maressa; Artoni, Roberto Ferreira; Vicari, Marcelo Ricardo; Moreira-Filho, Orlando; Camacho, Juan Pedro Martinez; Bakkali, Mohammed; de Oliveira, Claudio; Foresti, Fausto

2012-01-01

395

Apistogramma ortegai (Teleostei: Cichlidae), a new species of cichlid fish from the Ampyiacu River in the Peruvian Amazon basin.  

PubMed

Apistogramma ortegai, new species, is described from small streams tributaries of the Ampiyacu River near Pebas, in eastern Peru. It belongs to the Apistogramma regani species group and is distinguished from all other species of Apistogramma by the combination of contiguous caudal spot to bar 7, presence of abdominal stripes, short dorsal-fin lappets in both sexes, absence of vertical stripes on the caudal fin, and reduced number of predorsal and prepelvic scales. PMID:25283927

Britzke, Ricardo; Oliveira, Claudio; Kullander, Sven O

2014-01-01

396

Evolutionary history of the Lake Tanganyika cichlid tribe Lamprologini (Teleostei: Perciformes) derived from mitochondrial and nuclear DNA data.  

PubMed

Lake Tanganyika comprises a cichlid species flock with substrate-breeding and mouthbrooding lineages. While sexual selection via mate choice on male mating color is thought to boost speciation rates in mouthbrooding cichlids, this is not the case in substrate-breeding lamprologines, which mostly form stable pairs and lack sexual dichromatism. We present a comprehensive reconstruction of the evolution of the cichlid tribe Lamprologini, based upon mtDNA sequences and multilocus nuclear DNA (AFLP) markers. Twelve mtDNA clades were identified, seven of which were corroborated by the AFLP tree. The radiation is likely to have started about 5.3 MYA, contemporarily with that of the mouthbrooding C-lineage, and probably triggered by the onset of deep-water conditions in Lake Tanganyika. Neither the Congo- nor the Malagarazi River species form the most ancestral branch. Several conflicts in the mtDNA phylogeny with taxonomic assignments based upon color, eco-morphology and behavior could be resolved and complemented by the AFLP analysis. Introgressive hybridization upon secondary contact seems to be the most likely cause for paraphyly of taxa due to mtDNA capture in species involving brood-care helpers, while accidental hybridization best explains the para- or polyphyly of several gastropod shell breeders. Taxonomic error or paraphyly due to the survival of ancestral lineages appear responsible for inconsistencies in the genera Lamprologus and Neolamprologus. PMID:20601006

Sturmbauer, Christian; Salzburger, Walter; Duftner, Nina; Schelly, Robert; Koblmüller, Stephan

2010-10-01

397

Ancyrocephalidae (Monogenea) of Lake Tanganyika: II: description of the first Cichlidogyrus spp. parasites from Tropheini fish hosts (Teleostei, Cichlidae).  

PubMed

Although Lake Tanganyika hosts the most diverse endemic cichlid fish assemblage, its monogenean parasite fauna has hardly been documented. The cichlid tribe Tropheini has generated great interest because of its systematic position within the Haplochromini s.l. and its diversity in trophic morphology, reproductive behaviour and population structure. It has the potential to host a diverse Monogenea fauna. Here, we describe the first Cichlidogyrus spp.: Cichlidogyrus steenbergei sp. n., Cichlidogyrus irenae sp. n. and Cichlidogyrus gistelincki sp. n. The three host species, Limnotilapia dardennii, Ctenochromis horei and Gnathochromis pfefferi, are all infected by a single unique Cichlidogyrus sp. The genital and haptoral structure of the new species suggests a close relationship, which might mirror the close affinities between the hosts within the Tropheini. Based on haptoral configuration, the new species belong to a morphological group within the genus containing parasites both of West African cichlids and of Haplochromini, and hence, do not represent a new organisation of the attachment organ (as has recently been described of congeners infecting the ectodine cichlid Ophthalmotilapia). PMID:21710349

Gillardin, Céline; Vanhove, Maarten P M; Pariselle, Antoine; Huyse, Tine; Volckaert, Filip A M

2012-01-01

398

Genetic and Morphological Evidence Implies Existence of Two Sympatric Species in Cyathopharynx furcifer (Teleostei: Cichlidae) from Lake Tanganyika.  

PubMed

Although the cichlid fishes from Lake Tanganyika are treated as a textbook example of adaptive radiation, many taxonomic problems remain unresolved. Cyathopharynx furcifer, which belongs to the currently monospecific genus Cyathopharynx, contains two colour morphs at the southern end of the lake: one has a yellow anal fin, and the other has a black anal fin. Some books for hobbyists of ornamental fish treat these morphs as different species, but taxonomic studies have neither mentioned the existence nor addressed the status of these colour morphs. In the present paper, we analysed these two colour morphs using mitochondrial, microsatellite, morphometric, and meristic data sets. Both molecular and morphological data allowed clear discrimination between these morphs, suggesting the existence of two distinct sympatric species. Three taxonomic species have been described in this genus, and only C. furcifer is currently considered valid. Observations of type specimens of these three nominal species will be needed to determine the scientific names of these colour morphs. PMID:22675655

Takahashi, Tetsumi; Hori, Michio

2012-01-01

399

Geophagus crocatus, a new species of geophagine cichlid from the Berbice River, Guyana, South America (Teleostei: Cichlidae).  

PubMed

We describe a new Geophagus from the Berbice River of Guyana, bringing the total number of described species in the genus to 19, and of Guianese species to six.. Geophagus crocatus, new species, is distinguished from all species of Geophagus outside of the G. surinamensis group by the presence of an incomplete suborbital stripe (vs. complete), and the presence of six lateral bars, with bars 2 and 3 slightly sloping toward each other and fusing dorsally at the base of the dorsal fin. Geophagus crocatus is the only Geophagus species known from the Berbice River, and it is present above and below the Itabru Falls. PMID:25277570

Hauser, Frances E; López-Fernández, Hernán

2013-01-01

400

New insights into the complex structure and ontogeny of the occipito-vertebral gap in barbeled dragonfishes (Stomiidae, Teleostei).  

PubMed

In all stomiid genera there is an occipito-vertebral gap between the skull and the first vertebra bridged only by the flexible notochord. Morphological studies from the early 20th century suggested that some stomiid genera have 1-10 of the anteriormost centra reduced or entire vertebrae missing in this region. Our study reviews this previous hypothesis. Using a new approach, we show that only in Chauliodus, Eustomias and Leptostomias gladiator vertebral centra are actually lost, with their respective neural arches and parapophyses persisting. We present results from a comparative analysis of the number and insertion sites of the anteriormost myosepta in 26 of the 28 stomiid genera. Generally in teleosts the first three myosepta are associated with the occiput, and the fourth is the first vertebral myoseptum. The insertion site of the fourth myoseptum plays an important role in this analysis, because it provides a landmark for the first vertebra. Lack of association of the fourth myoseptum with a vertebra is thus evidence that the first vertebra is reduced or absent. By counting the occipital and vertebral myosepta the number of reduced vertebrae in Chauliodus, Eustomias and Leptostomias gladiator can be inferred. Proper identification of the spino-occipital nerves provides an additional source of information about vertebral reduction. In all other stomiid genera the extensive occipito- vertebral gap is not a consequence of the reduction of vertebrae, but of an elongation of the notochord. The complex structure and ontogeny of the anterior part of the vertebral column of stomiids are discussed comparatively. PMID:20623652

Schnell, Nalani K; Britz, Ralf; Johnson, G David

2010-08-01

401

Some aspects of the biology and ecology of Knipowitschia caucasica (Teleostei: Gobiidae) in the Evros Delta (North Aegean Sea)  

NASA Astrophysics Data System (ADS)

Some aspects of the biology and ecology of the goby Knipowitschia caucasica were studied over a period of 13 months in a poly-to euhaline area in the Evros Delta (North Aegean Sea). This fish grows rapidly in the summer and autumn after hatching, matures after its first winter, breeds from the end of April to the end of July, and grows rapidly again in July September. The older males perish after their second February, whereas some females have a second breeding season at the end of April/beginning of May, shortly before their death. The fish grows to about 40 mm in total length. There is a positive correlation between the total length (TL) and the standard length (SL) or the cleaned body weight (CW). SL increases slower than TL, whereas CW increases slower than TL in immature individuals and faster in males and females. There is no difference between immature individuals, males and females, in the growth rate of SL, TL and CW, TL. The mean monthly values of the condition factor varies from 0.289 to 0.576 in females and from 0.313 to 0.548 in males. The overall sex ratio of females to males is 1: 1.46. Fecundity ranges from 60 to 217 eggs with a mean value of 109.8 and depends upon size, whereas relative fecundity varies between 968 and 2170 with a mean of 1558. The fish feeds predominantly on benthic amphipods and polychaetes.

Kevrekidis, T.; Kokkinakis, A. K.; Koukouras, A.

1990-06-01

402

Intergeneric Spawning Between Captive Female Sacramento Perch (Archoplites interruptus) and Male Rock Bass (Ambloplites rupestrus), Teleostei: Centrarchidae  

Microsoft Academic Search

The North American freshwater fish family Centrarchidae is well known for extensive natural hybridization, but there are no reports of voluntary spawning between genera. We document courtship and spawning in an aquarium between two separate pairs of a male Rock Bass (Ambloplites rupestris) and a female Sacramento Perch (Archoplites interruptus). One trial resulted in a low frequency of fertilized eggs,

Daniel I. Bolnick; Chris E. Miller

2006-01-01

403

Mapping the potential distribution of the invasive Red Shiner, Cyprinella lutrensis (Teleostei: Cyprinidae) across waterways of the conterminous United States  

USGS Publications Warehouse

Predicting the future spread of non-native aquatic species continues to be a high priority for natural resource managers striving to maintain biodiversity and ecosystem function. Modeling the potential distributions of alien aquatic species through spatially explicit mapping is an increasingly important tool for risk assessment and prediction. Habitat modeling also facilitates the identification of key environmental variables influencing species distributions. We modeled the potential distribution of an aggressive invasive minnow, the red shiner (Cyprinella lutrensis), in waterways of the conterminous United States using maximum entropy (Maxent). We used inventory records from the USGS Nonindigenous Aquatic Species Database, native records for C. lutrensis from museum collections, and a geographic information system of 20 raster climatic and environmental variables to produce a map of potential red shiner habitat. Summer climatic variables were the most important environmental predictors of C. lutrensis distribution, which was consistent with the high temperature tolerance of this species. Results from this study provide insights into the locations and environmental conditions in the US that are susceptible to red shiner invasion.

Poulos, Helen M.; Chernoff, Barry; Fuller, Pam L.; Butman, David

2012-01-01

404

Molecular Systematics of Xenocyprinae (Teleostei: Cyprinidae): Taxonomy, Biogeography, and Coevolution of a Special Group Restricted in East Asia  

Microsoft Academic Search

We surveyed mitochondrial DNA (mtDNA) sequence variation in the subfamily Xenocyprinae from China and used these data to estimate intraspecific, interspecific, and intergeneric phylogeny and assess biogeographic scenarios underlying the geographic structure of lineages. We sequenced 1140 bp of cytochrome b from 30 individuals of Xenocyprinae and one putative outgroup (Myxocypris asiaticus) and also sequenced 297 bp of ND4L, 1380

Wuhan Xiao; Yaping Zhang; Huanzhang Liu

2001-01-01

405

Nested Clade and Phylogeographic Analyses of the Chub, Leuciscus cephalus (Teleostei, Cyprinidae), in Greece: Implications for Balkan Peninsula Biogeography  

Microsoft Academic Search

Phylogenetic relationships among Greek populations of the chub, Leuciscus cephalus, were investigated using 600 bp of the cytochrome b gene. The aim of this study was to test the assumption that the main difference in ichthyological composition between both sides of the Balkan Peninsula is directly linked to differences in the dispersion mechanisms used by fish in order to extend

Jean Dominique Durand; Alan R. Templeton; Bruno Guinand; Anastasia Imsiridou; Yvette Bouvet

1999-01-01

406

Neoplecostomus doceensis: a new loricariid species (Teleostei, Siluriformes) from the rio Doce basin and comments about its putative origin  

PubMed Central

Abstract A new species of Neoplecostomus is described from the rio Doce basin representing the first species of this genus in the basin. The new species is distinguished from its congeners by having enlarged, fleshy folds between dentaries, two or three series of developed papillae anterior to premaxillary teeth and a adipose-fin membrane present, and by lacking enlarged odontodes along snout lateral margins in mature males, a well-developed dorsal-fin spinelet wider than dorsal-fin spine base, lower number of lateral-line figs and developed membrane on the dorsal portion of the first, second and third pelvic-fin branched rays. Additionally, we present a brief discussion of biogeographic scenarios that may explain the distribution of the new species in the rio Doce basin. We suggested that the ancestral lineage of the new species reached the rio Doce from the upper portions of rio Paraná drainages about 3.5 Mya (95% HPD: 1.6–5.5) indicating a colonization route of the N. doceensis ancestral lineage from the south end of Serra do Espinhaço, probably as a result of headwater capture processes between the upper rio Paraná and rio Doce basins.

Roxo, Fabio F.; Silva, Gabriel S. C.; Zawadzki, Claudio H.; Oliveira, Claudio

2014-01-01

407

Male mate choice and sperm allocation in a sexual/asexual mating complex of Poecilia (Poeciliidae, Teleostei)  

PubMed Central

Male mate choice is critical for understanding the evolution and maintenance of sexual/asexual mating complexes involving sperm-dependent, gynogenetic species. Amazon mollies (Poecilia formosa) require sperm to trigger embryogenesis, but the males (e.g. Poecilia mexicana) do not contribute genes. Males benefit from mating with Amazon mollies, because such matings make males more attractive to conspecific females, but they might control the cost of such matings by providing less sperm to Amazon mollies. We examined this at the behavioural and sperm levels. P. mexicana males preferred to mate with, and transferred more sperm to conspecific females. However, if males mated with P. formosa, sperm was readily transferred. This underscores the importance of male choice in this system. PMID:17148157

Schlupp, I; Plath, M

2005-01-01

408

Substance P-like-immunoreactive neurons in the photosensory pineal organ of the rainbow trout, Salmo gairdneri Richardson (Teleostei).  

PubMed

Restricted numbers of substance P-like-immunoreactive (SPL-IR) neurons were demonstrated in the photosensory pineal organ of the rainbow trout. The small parapineal organ of this teleost species receives a distinct SPL-IR innervation via the habenular nuclei, but displays no intrinsic SPL-IR neurons. Intrapineal SPL-IR neurons were located in the rostral portion of the pineal end-vesicle. Neuronal somata were found in a lateral position with smooth axonal processes extending mediad. Immunoreactive somata and axonal processes were observed intraparenchymally as well as in the pineal lumen. The pattern of immunoreactivity was not changed in excised pineal organs that had been incubated in tissue culture medium in the dark for 18 h. The possibility that the intrapineal SPL-IR neurons are not part of the neural circuitry involved in the transduction of photic information, but may have other functions, is discussed. PMID:2430718

Ekström, P; Korf, H W

1986-01-01

409

Reprinted fromJ. Zool., Lond. (1981) 193, 517-530 Terrestrial feeding in the Mudskipper Periophthalmus (pisces: Teleostei)  

E-print Network

(Euphausia), goldfish (Carassius auratus), squid (Loligo), and earthworms (Lumbricus) as food. X in the centre of a 40 I plexiglass box containing 10 I of water. Both earthworms filled with a mixture of barium

Lauder, George V.

410

Ontogeny and homology of the skeletal elements that form the sucking disc of remoras (Teleostei, Echeneoidei, Echeneidae).  

PubMed

The sucking disc of the sharksuckers of the family Echeneidae is one of the most remarkable and most highly modified skeletal structures among vertebrates. We studied the development of the sucking disc based on a series of larval, juvenile, and adult echeneids ranging from 9.3 mm to 175 mm standard length. We revisited the question of the homology of the different skeletal parts that form the disc using an ontogenetic approach. We compared the initial stages of development of the disc with early developmental stages of the spinous dorsal fin in a representative of the morphologically basal percomorph Morone. We demonstrate that the "interneural rays" of echeneids are homologous with the proximal-middle radials of Morone and other teleosts and that the "intercalary bones" of sharksuckers are homologous with the distal radials of Morone and other teleosts. The "intercalary bones" or distal radials develop a pair of large wing-like lateral extensions in echeneids, not present in this form in any other teleost. Finally the "pectinated lamellae" are homologous with the fin spines of Morone and other acanthomorphs. The main part of each pectinated lamella is formed by bilateral extensions of the base of the fin spine just above its proximal tip, each of which develops a row of spinous projections, or spinules, along its posterior margin. The number of rows and the number of spinules increase with size, and they become autogenous from the body of the lamellae. We also provide a historical review of previous studies on the homology of the echeneid sucking disc and demonstrate that the most recent hypotheses, published in 2002, 2005 and 2006, are erroneous. PMID:22833478

Britz, Ralf; Johnson, G David

2012-12-01

411

Composition and structure of the parasite faunas of cod, Gadus morhua L. (Teleostei: Gadidae), in the North East Atlantic  

Microsoft Academic Search

BACKGROUND: Although numerous studies on parasites of the Atlantic cod, Gadus morhua L. have been conducted in the North Atlantic, comparative analyses on local cod parasite faunas are virtually lacking. The present study is based on examination of large samples of cod from six geographical areas of the North East Atlantic which yielded abundant baseline data on parasite distribution and

Diana Perdiguero-Alonso; Francisco E Montero; Juan Antonio Raga; Aneta Kostadinova

2008-01-01

412

Postglacial recolonization of eastern Blacknose Dace,Rhinichthys atratulus(Teleostei: Cyprinidae), through the gateway of New England  

PubMed Central

During the last ice age, much of North America far south as 40°N was covered by glaciers (Hewitt 2000). About 20,000 years ago, as the glaciers retreated, the hydrologic landscape changed dramatically creating waterways for fish dispersal. The number of populations responsible for recolonization and the regions from which they recolonized are unknown for many freshwater fishes living in New England and southeastern Canada. The Blacknose Dace,Rhinichthys atratulus, is one of the freshwater fish species that recolonized this region. We hypothesize that the earliest deglaciated region, modern-day Connecticut, was recolonized byR. atratulusvia a single founding event by a single population. In this paper, we test this hypothesis phylogenetically with regard to the major drainage basins within Connecticut. The mitochondrial DNA exhibits low nucleotide diversity, high haplotype diversity, and a dominant haplotype found across the state. A small percentage of individuals in the Housatonic drainage basin, however, share a haplotype with populations in New York drainage basins, a haplotype not found elsewhere in Connecticut's drainage basins. We calculated a range for the rate of divergence for NADH dehydrogenase subunit 2 (nd2) and control region (ctr) of 4.43–6.76% and 3.84–8.48% per million years (my), respectively. While this range is higher than the commonly accepted rate of 2% for mitochondrial DNA, these results join a growing list of publications finding high rates of divergence for various taxa (Peterson and Masel 2009). The data support the conclusion that Connecticut as a whole was recolonized initially by a single founding event that came from a single refugium. Subsequently, the Housatonic basin alone experienced a secondary recolonization event. PMID:22393505

Tipton, Michelle L; Gignoux-Wolfsohn, Sarah; Stonebraker, Phoebe; Chernoff, Barry

2011-01-01

413

Laboratory food choice by the mosshead sculpin, Clinocottus globiceps (Girard) (Teleostei; Cottidae), a predator of sea anemones  

Microsoft Academic Search

Mosshead sculpins, Clinocottus globiceps (Girard), are unique among rocky intertidal fishes of the North American Pacific coast in preying heavily upon sea anemones. We examined food choice by C. globiceps for various food types offered simultaneously in laboratory trials. Both large and small C. globiceps attacked anemones (Anthopleura elegantissima (Brandt) and Epiactis prolifera (Verrill)) more frequently than shrimp or algae,

Ronald M. Yoshiyama; W. David Wallace; Jacqueline L. Burns; Ann L. Knowlton; Jill R. Welter

1996-01-01

414

Evolutionary history of Otophysi (Teleostei), a major clade of the modern freshwater fishes: Pangaean origin and Mesozoic radiation  

Microsoft Academic Search

Background  Freshwater harbors approximately 12,000 fish species accounting for 43% of the diversity of all modern fish. A single ancestral\\u000a lineage evolved into about two-thirds of this enormous biodiversity (? 7900 spp.) and is currently distributed throughout\\u000a the world's continents except Antarctica. Despite such remarkable species diversity and ubiquity, the evolutionary history\\u000a of this major freshwater fish clade, Otophysi, remains largely

Masanori Nakatani; Masaki Miya; Kohji Mabuchi; Kenji Saitoh; Mutsumi Nishida

2011-01-01

415

Further Evidence for the Invasion and Establishment of Pterois volitans (Teleostei: Scorpaenidae) Along the Atlantic Coast of the United States  

Microsoft Academic Search

Abstract - We document the continued population expansion of red lionfish, Pieroia voUiiins. the first documcnied,successful,introduction of an invasive marine,fish species from the western Paeific to Atlantic coastal waters of the United States. Red lionfish are indigenous,to the Indo-Pacific and have apparently established one or more,breeding,populations,on reefs off the southeastern,United States. Fifty-nine specimens, most presumably adult red lionfish. were documented

H. Scott Meister; David M. Wyanski; Joshua K. Loefer; Steve W. Ross; Andrea M. Quattrini; Kenneth J. Sulak

2005-01-01

416

Experimentally induced pigment changes in small African 'Barbus' (Teleostei: Cyprinidae): Synonymy of 'Barbus' amphigramma and 'Barbus' taitensis with 'Barbus' paludinosus  

USGS Publications Warehouse

Pigmentation in fishes is known to be variable both among individuals of a species and within individuals over time. Use of pigment characters for taxonomic diagnoses must, therefore, be carefully considered. I present experimental evidence showing that pigment characters previously considered diagnostic for three small African 'Barbus' species may differ between living and preserved specimens and that lasting changes in these characters can be induced experimentally by placing fishes in a different, less turbid environment. Lateral line pigmentation and presence of a spot on the caudal peduncle showed significant changes that resulted in different species identifications before and after the experiment. These pigment patterns are thereby shown to be labile, nontrenchant characters having little or no diagnostic utility. 'Barbus' amphigramma Boulenger, 1903, and 'Barbus' taitensis Gu??nther, 1894, are thus shown to be junior synonyms of 'Barbus' paludinosus Peters, 1852.

Farm, B.P.

2001-01-01

417

Phylogenetic relationships within the speciose family Characidae (Teleostei: Ostariophysi: Characiformes) based on multilocus analysis and extensive ingroup sampling  

PubMed Central

Background With nearly 1,100 species, the fish family Characidae represents more than half of the species of Characiformes, and is a key component of Neotropical freshwater ecosystems. The composition, phylogeny, and classification of Characidae is currently uncertain, despite significant efforts based on analysis of morphological and molecular data. No consensus about the monophyly of this group or its position within the order Characiformes has been reached, challenged by the fact that many key studies to date have non-overlapping taxonomic representation and focus only on subsets of this diversity. Results In the present study we propose a new definition of the family Characidae and a hypothesis of relationships for the Characiformes based on phylogenetic analysis of DNA sequences of two mitochondrial and three nuclear genes (4,680 base pairs). The sequences were obtained from 211 samples representing 166 genera distributed among all 18 recognized families in the order Characiformes, all 14 recognized subfamilies in the Characidae, plus 56 of the genera so far considered incertae sedis in the Characidae. The phylogeny obtained is robust, with most lineages significantly supported by posterior probabilities in Bayesian analysis, and high bootstrap values from maximum likelihood and parsimony analyses. Conclusion A monophyletic assemblage strongly supported in all our phylogenetic analysis is herein defined as the Characidae and includes the characiform species lacking a supraorbital bone and with a derived position of the emergence of the hyoid artery from the anterior ceratohyal. To recognize this and several other monophyletic groups within characiforms we propose changes in the limits of several families to facilitate future studies in the Characiformes and particularly the Characidae. This work presents a new phylogenetic framework for a speciose and morphologically diverse group of freshwater fishes of significant ecological and evolutionary importance across the Neotropics and portions of Africa. PMID:21943181

2011-01-01

418

Anatomia funcional e morfometria dos intestinos e dos cecos pilóricos do teleostei (pisces) de água doce Brycon orbignyanus (Valenciennes, 1849)  

Microsoft Academic Search

The objective of the present work was to study the functional anatomy and the comparative morphometry in the medium and posterior intestines and in the piracanjuba (Brycon orbignyanus Valenciennes, 1849) (Characiformes, Characidae, Bryconinae) piloric cecum. Anatomofunctional and morphometric studies were carried out in the medium and posterior intestines and in the piloric cecum of this specie with omnivore feeding behavior.

José Teixeira de Seixas Filho; José de Moura Brás; Andréa Tassis de Mendonça Gomide; Maria Goreti de Almeida Oliveira; Juarez Lopes Donzele; Eliane Menin

2000-01-01

419

Opsin-immunoreactive outer segments and acetylcholinesterase-positive neurons in the pineal complex of Phoxinus phoxinus (Teleostei, Cyprinidae)  

Microsoft Academic Search

Summary  The pineal complex of the teleost, Phoxinus phoxinus L., was studied light-microscopically by the use of the indirect immunocytochemical antiopsin reaction and the histochemical acetylcholinersterase (AChE) method.Opsin-immunoreactive outer segments of photoreceptor cells were demonstrated in large numbers in all divisions of the pineal end-vesicle and in the pineal stalk. Moreover, they were found in the roof of the third ventricle,

I. Vigh-Teichmann; H.-W. Korf; A. Oksche; B. Vigh

1982-01-01

420

Apareiodon Eigenmann, 1916 (Teleostei, Characiformes), from the Tocantins-Araguaia Basin, with Description of Three New Species  

Microsoft Academic Search

Apareiodon species from the Rio Tocantins-Araguaia basin, Brazil, were investigat- ed to determine the recognizable species in that basin. Apareiodon machrisi Travas- sos, 1957, the only previously described species reported for the Rio Tocantins- Araguaia basin, is recognized as valid, and three new species inhabiting primarily headwater streams are described (Apareiodon argenteus, Apareiodon cavalcante, and Apareiodon tigrinus). The species are

Carla Simone Pavanelli; Heraldo Antonio Britski; S. A. Schaefer

2003-01-01

421

A new record of a flathead fish (Teleostei: Platycephalidae) from China based on morphological characters and DNA barcoding  

NASA Astrophysics Data System (ADS)

A new record of Platycephalus sp.1 (sensu Nakabo, 2002) was documented based on morphological characters and DNA barcoding. We collected 174 specimens of the genus Platycephalus from Chinese coastal waters of Dongying, Qingdao, Zhoushan, and Beihai. Samples were identified as Platycephalus sp.1 morphologically. The coloration, meristic traits, and morphometric measurements are consistent with previously published records. In brief, it is an orange-brown flathead fish with dark brown spots scattered on head and body, lateral line scales 83 to 99 with one or two spine-bearing anteriormost pored scale, no yellow blotch on the caudal fin. Cytochrome oxidase I subunit (COI) gene fragments were sequenced for phylogenetic analysis. The mean evolutionary distance within the species Platycephalus sp.1 was 0.1%. Net evolutionary distances between Platycephalus sp.1 and other species of Platycephalus ranged from 10.8% to 19.7%, which is much greater than the threshold for species delimitation. The COI sequence analysis strongly supports the validity of Platyceohalus sp.1 at genetic level.

Qin, Yan; Song, Na; Zou, Jianwei; Zhang, Zhaohui; Cheng, Guangping; Gao, Tianxiang; Zhang, Xiumei

2013-05-01

422

Phylogenetic relationships and biogeographical patterns in Circum-Mediterranean subfamily Leuciscinae (Teleostei, Cyprinidae) inferred from both mitochondrial and nuclear data  

PubMed Central

Background Leuciscinae is a subfamily belonging to the Cyprinidae fish family that is widely distributed in Circum-Mediterranean region. Many efforts have been carried out to deciphering the evolutionary history of this group. Thus, different biogeographical scenarios have tried to explain the colonization of Europe and Mediterranean area by cyprinids, such as the "north dispersal" or the "Lago Mare dispersal" models. Most recently, Pleistocene glaciations influenced the distribution of leuciscins, especially in North and Central Europe. Weighing up these biogeographical scenarios, this paper constitutes not only the first attempt at deciphering the mitochondrial and nuclear relationships of Mediterranean leuciscins but also a test of biogeographical hypotheses that could have determined the current distribution of Circum-Mediterranean leuciscins. Results A total of 4439 characters (mitochondrial + nuclear) from 321 individuals of 176 leuciscine species rendered a well-supported phylogeny, showing fourteen main lineages. Analyses of independent mitochondrial and nuclear markers supported the same main lineages, but basal relationships were not concordant. Moreover, some incongruence was found among independent mitochondrial and nuclear phylogenies. The monophyly of some poorly known genera such as Pseudophoxinus and Petroleuciscus was rejected. Representatives of both genera belong to different evolutionary lineages. Timing of cladogenetic events among the main leuciscine lineages was gained using mitochondrial and all genes data set. Conclusions Adaptations to a predatory lifestyle or miniaturization have superimposed the morphology of some species. These species have been separated into different genera, which are not supported by a phylogenetic framework. Such is the case of the genera Pseudophoxinus and Petroleuciscus, which real taxonomy is not well known. The diversification of leuciscine lineages has been determined by intense vicariant events following the paleoclimatological and hydrogeological history of Mediterranean region. We propose different colonization models of Mediterranean region during the early Oligocene. Later vicariance events promoted Leuciscinae diversification during Oligocene and Miocene periods. Our data corroborate the presence of leuciscins in North Africa before the Messinian salinity crisis. Indeed, Messinian period appears as a stage of gradually Leuciscinae diversification. The rise of humidity at the beginning of the Pliocene promoted the colonization and posterior isolation of newly established freshwater populations. Finally, Pleistocene glaciations determined the current European distribution of some leuciscine species. PMID:20807419

2010-01-01

423

Ancyrocephalidae (Monogenea) of Lake Tanganyika: II: description of the first Cichlidogyrus spp. parasites from Tropheini fish hosts (Teleostei, Cichlidae)  

Microsoft Academic Search

Although Lake Tanganyika hosts the most diverse endemic cichlid fish assemblage, its monogenean parasite fauna has hardly\\u000a been documented. The cichlid tribe Tropheini has generated great interest because of its systematic position within the Haplochromini\\u000a s.l. and its diversity in trophic morphology, reproductive behaviour and population structure. It has the potential to host\\u000a a diverse Monogenea fauna. Here, we describe

Céline Gillardin; Maarten P. M. Vanhove; Antoine Pariselle; Tine Huyse; Filip A. M. Volckaert

424

Histologische Untersuchungen bei Carassius carassius auratus L. (Pisces, Teleostei) nach starkem Befall durch Trichodina domerguei Wallengreen, 1897 (Protozoa, Euciliata)  

Microsoft Academic Search

Zusammenfassung Es wird über einen Befall mit dem peritrichen Ciliaten Trichodina (Cyclochaeta) domerguei bei Goldfischen (Carassius carassius auratus L.) berichtet, an dem die Tiere eingingen. Auf Grund des histologischen Befundes konnte festgestellt werden, daß die Parasiten auch in der Lage sind, in das Gewebe einzudringen, wodurch Löcher, Gänge und Höhlen in den Kiemen entstehen, die zum Tod der Wirte führen.

Werner Frank

1962-01-01

425

Review of the crevalle jacks, Caranx hippos complex (Teleostei: Carangidae), with a description of a new species from West Africa  

USGS Publications Warehouse

The Caranx hippos species complex comprises three extant species: crevalle jack (Caranx hippos) (Linnaeus, 1766) from both the western and eastern Atlantic oceans; Pacific crevalle jack (Caranx caninus) Gu??nther, 1868 from the eastern Pacific Ocean; and longfin crevalle jack (Caranx fischeri) new species, from the eastern Atlantic, including the Mediterranean Sea and Ascension Island. Adults of all three species are superficially similar with a black blotch on the lower half of the pectoral fin, a black spot on the upper margin of opercle, one or two pairs of enlarged symphyseal canines on the lower jaw, and a similar pattern of breast squamation. Each species has a different pattern of hyperostotic bone development and anal-fin color. The two sympatric eastern Atlantic species also differ from each other in number of dorsal- and anal-fin rays, and in large adults of C. fischeri the lobes of these fins are longer and the body is deeper. Caranx hippos from opposite sides of the Atlantic are virtually indistinguishable externally but differ consistently in the expression of hyperostosis of the first dorsal-fin pterygiophore. The fossil species Caranx carangopsis Steindachner 1859 appears to have been based on composite material of Trachurus sp. and a fourth species of the Caranx hippos complex. Patterns of hyperostotic bone development are compared in the nine (of 15 total) species of Caranx sensu stricto that exhibit hyperostosis.

Smith-Vaniz, W.F.; Carpenter, K.E.

2007-01-01

426

Early development of the postcranial skeleton of the pikeperch Sander lucioperca (Teleostei: Percidae) relating to developmental stages and growth.  

PubMed

The early development of the postcranial skeleton (pectoral girdle, pelvic girdle, vertebral column and fins) in pikeperch (Sander lucioperca (L.)) was studied from hatching to days 47 and 43 post fertilization (dpf) at two different rearing temperatures, 15.5 and 18.0°C. Four embryonic and six larval stages were described, ranging from 3.4 ± 0.3 mm to 21.8 ± 2.1 mm in total length. The crucial point in larval development is swimbladder inflation, which enables larvae to swim energy efficiently. Until this time point, only the most essential skeletal elements to enable swimming movements have developed. As the larvae become neutrally buoyant, they grow and differentiate postcranial elements rapidly. Concurrently, swimming performance and foraging success seems to improve. A specific size is correlated with a distinct developmental stage defined by a set of traits that includes the skeletal elements. The developmental sequence of skeletal structures is temperature independent, although growth is slower and the individual developmental stages are reached later at 15.5°C than at 18.0°C. PMID:22505228

Ott, Alice; Löffler, Jasmin; Ahnelt, Harald; Keckeis, Hubert

2012-08-01

427

Karyotype and genome size of Iberochondrostoma almacai (Teleostei, Cyprinidae) and comparison with the sister-species I.lusitanicum  

PubMed Central

This study aimed to define the karyotype of the recently described Iberian endemic Iberochondrostoma almacai, to revisit the previously documented chromosome polymorphisms of its sister species I.lusitanicum using C-, Ag-/CMA3 and RE-banding, and to compare the two species genome sizes. A 2n = 50 karyotype (with the exception of a triploid I.lusitanicum specimen) and a corresponding haploid chromosome formula of 7M:15SM:3A (FN = 94) were found. Multiple NORs were observed in both species (in two submetacentric chromosome pairs, one of them clearly homologous) and a higher intra and interpopulational variability was evidenced in I.lusitanicum. Flow cytometry measurements of nuclear DNA content showed some significant differences in genome size both between and within species: the genome of I. almacai was smaller than that of I.lusitanicum (mean values 2.61 and 2.93 pg, respectively), which presented a clear interpopulational variability (mean values ranging from 2.72 to 3.00 pg). These data allowed the distinction of both taxa and confirmed the existence of two well differentiated groups within I. lusitanicum: one that includes the populations from the right bank of the Tejo and Samarra drainages, and another that reunites the southern populations. The peculiar differences between the two species, presently listed as “Critically Endangered”, reinforced the importance of this study for future conservation plans. PMID:21637679

2009-01-01

428

Loss of genetic diversity at an MHC locus in the endangered Tokyo bitterling Tanakia tanago (Teleostei: Cyprinidae).  

PubMed

Genetic diversity at a major histocompatibility complex (MHC) class II B gene was examined for two wild and three captive populations of the endangered Tokyo bitterling Tanakia tanago. A specific primer set was first developed to amplify the MHC II B exon 2 locus. Using single strand conformation polymorphism (SSCP) and sequencing analysis, 16 DAB3 alleles were detected with 56 nucleotide substitutions in the 276-bp region. In the putative antigen-binding sites of exon 2, the rate of nonsynonymous substitutions was significantly higher than that of synonymous substitutions (dN/dS = 2.79), indicating positive selection on the retention of polymorphism. The population from the Handa Natural Habitat Conservation Area and that from the Tone River system exhibited low variation (one and three alleles, respectively), whereas the captive population that originated from a mix of three distinct populations had the highest amounts of variation (14 alleles). The levels of heterozygosity at the MHC varied considerably among populations and showed significant correlations with those at putative neutral microsatellite markers, suggesting that genetic drift following a bottleneck has affected MHC variability in some populations. Comparisons between endangered and non-endangered fish species in previous reports and the present results indicate that the number of MHC alleles per population is on average 70% lower in endangered species than non-endangered species. Considering the functional consequence of this locus, attention should be paid to captive and wild endangered fish populations in terms of further loss of MHC alleles. PMID:24320188

Kubota, Hitoshi; Watanabe, Katsutoshi

2013-12-01

429

Phylogenetic relationships and timing of diversification in gonorynchiform fishes inferred using nuclear gene DNA sequences (Teleostei: Ostariophysi).  

PubMed

The Gonorynchiformes are the sister lineage of the species-rich Otophysi and provide important insights into the diversification of ostariophysan fishes. Phylogenies of gonorynchiforms inferred using morphological characters and mtDNA gene sequences provide differing resolutions with regard to the sister lineage of all other gonorynchiforms (Chanos vs. Gonorynchus) and support for monophyly of the two miniaturized lineages Cromeria and Grasseichthys. In this study the phylogeny and divergence times of gonorynchiforms are investigated with DNA sequences sampled from nine nuclear genes and a published morphological character matrix. Bayesian phylogenetic analyses reveal substantial congruence among individual gene trees with inferences from eight genes placing Gonorynchus as the sister lineage to all other gonorynchiforms. Seven gene trees resolve Cromeria and Grasseichthys as a clade, supporting previous inferences using morphological characters. Phylogenies resulting from either concatenating the nuclear genes, performing a multispecies coalescent species tree analysis, or combining the morphological and nuclear gene DNA sequences resolve Gonorynchus as the living sister lineage of all other gonorynchiforms, strongly support the monophyly of Cromeria and Grasseichthys, and resolve a clade containing Parakneria, Cromeria, and Grasseichthys. The morphological dataset, which includes 13 gonorynchiform fossil taxa that range in age from Early Cretaceous to Eocene, was analyzed in combination with DNA sequences from the nine nuclear genes and a relaxed molecular clock to estimate times of evolutionary divergence. This "tip dating" strategy accommodates uncertainty in the phylogenetic resolution of fossil taxa that provide calibration information in the relaxed molecular clock analysis. The estimated age of the most recent common ancestor (MRCA) of living gonorynchiforms is slightly older than estimates from previous node dating efforts, but the molecular tip dating estimated ages of Kneriinae (Kneria, Parakneria, Cromeria, and Grasseichthys) and the two paedomorphic lineages, Cromeria and Grasseichthys, are considerably younger. PMID:25087656

Near, Thomas J; Dornburg, Alex; Friedman, Matt

2014-11-01

430

Phylogenetic patterns in populations of Chilean species of the genus Orestias (Teleostei: Cyprinodontidae): results of mitochondrial DNA analysis.  

PubMed

Patterns of molecular genetic differentiation among taxa of the "agassii species complex" (Parenti, 1984) were analysed based on partial mtDNA control region sequences. Special attention has been paid to Chilean populations of Orestias agassii and species from isolated lakes of northern Chile, e.g., O. agassii, Orestias chungarensis, Orestias parinacotensis, Orestias laucaensis, and Orestias ascotanensis. Orestias tschudii, Orestias luteus, and Orestias ispi were analysed comparatively. Our findings support the utility of mtDNA control region sequences for phylogenetic studies within the "agassii species complex" and confirmed the monophyly of this particular lineage, excluding O. luteus. However, the monophyly of further morphologically defined lineages within the "agassii complex" appears doubtful. No support was found for the utility of these data sets for inferring phylogenetic relationships between more distantly related taxa originating from Lake Titicaca. PMID:12967616

Lüssen, Arne; Falk, Thomas M; Villwock, Wolfgang

2003-10-01

431

A new Pseudophoxinus (Teleostei, Cyprinidae) species from Southwestern Anatolia, with remarks on the distribution of the genus in western Anatolia  

PubMed Central

Abstract Pseudophoxinus burduricus sp. n. is described from drainages of Salda and Burdur lakes, southwestern Turkey. It is distinguished from other Anatolian Pseudophoxinus by a combination of characters: lateral line incomplete, with 21–39 (commonly 26–37) perforated scales and 47–57+1-2 scales in lateral series; 10½–12½ scale rows between lateral line and dorsal fin origin, 3–4(5) scale rows between lateral line and the pelvic fin origin; dorsal fin commonly with 7½ branched rays; anal fin commonly with 6½ branched rays; 7–8(9) gill rakers on the first branchial arch; a faint and diffuse epidermal black stripe from eye to caudal fin base in alive and preserved individuals; mouth slightly subterminal, tip of mouth cleft on about level of lower margin of eye; snout rounded, its length greater than eye diameter. Comparison is given with all Pseudophoxinus species from western Anatolia. PMID:23950681

Kucuk, Fahrettin; Gulle, Iskender; Guclu, S. Serkan; Ciftci, Y?lmaz; Erdogan, Omer

2013-01-01

432

A systematic revision of the large-scaled Marcusenius with description of a new species from Cameroon (Teleostei; Osteoglossomorpha;  

E-print Network

-Central and Central Africa. A detailed morphometric analysis could not distinguish differences between M. moorii, M is given. KEYWORDS:Systematics, morphometrics, Mormyridae, Marcusenius, Central Africa. Introduction

Hopkins, Carl D.

433

New Species of Aphanius (Teleostei, Cyprinodontidae) from Isfahan Province of Iran and a Reanalysis of Other Iranian Species  

E-print Network

/Miocene boundary (Smith et al., 1995). The distribution includes coastal areas of the Mediterranean region and the Gir Peninsula of northwestern India to northeastern Somalia, including the Red Sea and the Persian Gulf. Inland distribution is restricted primarily to the Mediterranean and the Near East orogenic belt

Hrbek, Tomas - Department of Biology, Universidad de Puerto Rico

434

The Development of Lateral-Line Receptors in Eigenmannia (Teleostei, Gymnotiformes). II. The Electroreceptive Lateral-Line System  

Microsoft Academic Search

Weakly electric fish of the genus Eigenmannia were induced to spawn in conditions simulating the tropical rainy season. The skin of embryos of different ages was prepared for histological examination, and whole animals were examined by various histological methods and scanning electron microscopy. It was found that the electrosensory system develops after the first mechanoreceptive lines have formed. The tuberous

Heinrich A. Vischer

1989-01-01

435

Transient ontogenetic expression of hermaphroditic gonad morphology within the Gobiosoma group of the Neotropical seven-spined gobies (Teleostei: Gobiidae)  

Microsoft Academic Search

The Neotropical seven-spined gobies (tribe Gobiosomatini), including the Gobiosoma and Microgobius groups, constitute a speciose,\\u000a monophyletic gobiid taxon. In particular, member species of the Gobiosoma group exhibit a combination of behavioral diversification\\u000a and microhabitat specialization that may have played a major role in their collective rapid evolution and high rate of speciation.\\u000a Functional hermaphroditism, which is common among gobiids, can

Kathleen S. Cole

2008-01-01

436

Electron microscopical studies of gonads in primary and secondary males of protogynous hermaphroditic fish Coris julis L. (Labridae, Teleostei)  

Microsoft Academic Search

Summary Electron microscopical examinations ofCoris julis (L.) showed that Leydig cells are definitely present in the gonads of primary, as well as of secondary males. During sex change the Leydig cells develop from the remnants of the overy in the newly organized testes.

B. J. Duchac; A. M. Nemella; E. M. Bühler

1983-01-01

437

Three sympatric karyomorphs in the fish Astyanax fasciatus (Teleostei, Characidae) do not seem to hybridize in natural populations.  

PubMed

Ninety individuals of the characid fish Astyanax fasciatus (Cuvier, 1819) were collected at Água da Madalena stream (Botucatu, São Paulo, Brazil) and analyzed for diploid chromosome number 2n and karyotype composition as well as for the chromosomal location of the 5S and 18S ribosomal DNA (rDNA). Whereas no chromosome differences were associated with sex, three different karyomorphs with diploid chromosome numbers 2n=46, 2n=48 and 2n=50 were found. No intermediate 2n numbers were discovered. The 2n=50 karyomorph showed some differences in 18S rDNA location compared to the two other karyomorphs. Finally, all specimens with the 2n=46 karyomorph showed the presence of a partly heterochromatic macro supernumerary chromosome, which was absent in all individuals with the two other karyomorphs. All these results suggest that indviduals of the three different karyomorphs are not likely to hybridize in the examined populations. Our findings strongly suggest the presence of three separate species (sensu biological species concept) easily diagnosed on the basis of differences in the diploid chromosome numbers and other chromosomal markers. PMID:24260650

Ferreira-Neto, Maressa; Artoni, Roberto Ferreira; Vicari, Marcelo Ricardo; Moreira-Filho, Orlando; Camacho, Juan Pedro Martínez; Bakkali, Mohammed; de Oliveira, Claudio; Foresti, Fausto

2012-01-01

438

Light and ultrastructural description of Meglitschia mylei n. sp. (myxozoa) from Myleus rubripinnis (Teleostei: Serrasalmidae) in the Amazon River system.  

PubMed

Meglitschia mylei n. sp. found in the gall bladder of the teleostean fish Myleus rubripinnis (Serrasalmidae) from the middle Amazonian region of Brazil is described using light and transmission electron microscopy. The spores observed in the bile averaged 24.6±0.8 ?m long, 8.7±0.4 ?m wide and 5.1±0.3 ?m thick and were strongly furcate and arcuate ?-shaped composed of two symmetric equal-sized valves, up to ?70 nm thick. Each valve possessed one opposed tapering appendage, 20.1±0.7 ?m long, oriented parallel towards the basal tip of the appendages and joined along a right suture line forming a thick strand. The strand goes around the central part of the spore, which in turn surrounds two equal and symmetric spherical polar capsules (PC), 2.1±0.3 ?m in diameter, located at the same level. Each capsule contains a polar filament with five (rarely six) coils. The binucleate sporoplasm was irregular in shape, contained several sporoplasmosomes, ?175 nm in diameter and filled all the space of the two caudal appendages. Based on the arc shape of the spore with two tapering caudal appendages oriented to the basis of spores, on the number and position of the PC and of the polar filament coils and arrangements, and on the host specificity, we propose the name M. mylei n. sp. for this new myxozoan. Accordingly, this is the second described species of this genus. PMID:21895844

Azevedo, Carlos; Ribeiro, Mariana; Clemente, Sérgio C S; Casal, Graça; Lopes, Leila; Matos, Patrícia; Al-Quraishy, Saleh A; Matos, Edilson

2011-01-01

439

Ovarian follicular atresia is mediated by heterophagy, autophagy, and apoptosis in Prochilodus argenteus and Leporinus taeniatus (Teleostei: Characiformes).  

PubMed

We investigated apoptosis, cell proliferation antigen (PCNA), and heat shock protein (HSP70) during ovarian follicular atresia in two freshwater teleost species from the São Francisco River basin, Brazil: curimatã-pacu, Prochilodus argenteus and piau-jejo, Leporinus taeniatus. Fishes were maintained in captivity after the reproductive period and ovarian regression was assessed by gonadosomatic index for three stages: early, advanced, and late regression. Follicular atresia was analysed by light and transmission electron microscopy, as well as by TUNEL and immunohistochemistry for HSP70 and PCNA. During early regression, atretic follicles exhibited zona pellucida breakdown, yolk degeneration, and hypertrophied follicular cells (e.g., granulosa in mammals). Intense heterophagy to engulf the yolk, and autophagy were detected in the follicular cells during advanced and late atresia. The TUNEL assay detected DNA fragmentation, mainly in late follicular atresia. The apoptosis rate of the follicular cells increased up to 10% during follicular atresia in both species and was negatively correlated with follicular area. Immunohistochemistry reaction for HSP70 stained the follicular cells strongly during advanced atresia, when they are intensively involved in yolk engulfment, whereas the reaction for PCNA labelled theca cells. We inferred that heterophagy, autophagy, and apoptosis contributed to follicular atresia in teleost ovaries, thereby achieving a more efficient removal of the degenerating oocyte and dying follicular cells. Additionally, HSP70 may protect the follicular cells before apoptosis when they are involved in yolk engulfment, and cell proliferation in the theca contributed to ovarian remodelling. PMID:18701155

Santos, H B; Thomé, R G; Arantes, F P; Sato, Y; Bazzoli, N; Rizzo, E

2008-12-01

440

The role of continental shelf width in determining freshwater phylogeographic patterns in south-eastern Australian pygmy perches (Teleostei: Percichthyidae).  

PubMed

Biogeographic patterns displayed by obligate freshwater organisms are intimately related to the nature and extent of connectivity between suitable habitats. Two of the more significant barriers to freshwater connections are seawater and major drainage divides. South-eastern Australia provides a contrast between these barriers as it has discrete areas that are likely influenced to a greater or lesser extent by each barrier type. We use continental shelf width as a proxy for the potential degree of river coalescence during low sea levels. Our specific hypothesis is that the degree of phylogeographic divergence between coastal river basins should correspond to the continental shelf width of each region. This predicts that genetic divergences between river basins should be lowest in regions with a wider continental shelf and that regions with similar continental shelf width should have similar genetic divergences. Pygmy perches (Nannoperca australis and Nannoperca 'flindersi') in south-eastern Australia provide an ideal opportunity to test these biogeographic hypotheses. Phylogeographic patterns were examined based on range-wide sampling of 82 populations for cytochrome b and 23 polymorphic allozyme loci. Our results recovered only limited support for our continental shelf width hypothesis, although patterns within Bass clade were largely congruent with reconstructed low sea-level drainage patterns. In addition, we identified several instances of drainage divide crossings, typically associated with low elevational differences. Our results demonstrate high levels of genetic heterogeneity with important conservation implications, especially for declining populations in the Murray-Darling Basin and a highly restricted disjunct population in Ansons River, Tasmania. PMID:23398527

Unmack, Peter J; Hammer, Michael P; Adams, Mark; Johnson, Jerald B; Dowling, Thomas E

2013-03-01

441

Taxonomic validity and phylogenetic relationships of a newly-described tooth-carp, Aphanius mesopotamicus Coad, 2009 (Teleostei: Cyprinodontidae).  

PubMed

Variation among complete cytb sequences (1140 bp) of Aphanius mesopotamicus Coad, 2009 was compared with closely related species, to investigate the validity of this taxon as a newly-described tooth-carp based on morphological characteristics. Maximum likelihood and Bayesian likelihood trees supported the monophyly of A. mesopotamicus and its sister group relationship to A. sophiae. Some 10-16 differences were found when compared to four different population samples of A. sophiae, whereas, intraspecific differences were only up to 6 bp. These distances suggest divergence from a common ancestor with A. sophiae at roughly 1 million years ago. These results are congruent with morphology-based hypotheses, indicating a recent speciation event. PMID:24871855

Alavi-Yeganeh, Mohammad Sadegh; Keivany, Yazdan; Seyfabadi, Jafar; Kazemi, Bahram; Wallis, Graham P

2014-01-01

442

Growth of striated muscle fibres in the M. lateralis of the European eel Anguilla anguilla (L.) (Pisces, Teleostei).  

PubMed Central

Diameters of red and white muscle fibres were measured in the M. lateralis of eels cultured under laboratory circumstances over a period of 2 years, starting from the glass eel stage. The red fibres of eels less than 10 cm are unique in that their growth involves increase in diameter only. Growth of the red fibres in eels greater than 10 cm, and of the white fibres in eels at all lengths considered, is characterized by an increase in number as well as diameter, the relative importance of these two methods of growth being related to factors other than the length of the animal. Satellite cells may play an important part in the addition of new, small muscle fibres. Images Fig. 8 PMID:640952

Willemse, J J; van den Berg, P G

1978-01-01

443

On?shore entrainment of circatidal rhythmicity in Lipophrys pholis (teleostei) by natural zeitgeber and the inhibitory effect of cageing  

Microsoft Academic Search

The rocky shore fish, Lipophrys pholis, possesses an endogenous circatidal activity rhythm that eventually declines under constant conditions. Such arhythmic fish can be entrained by exposure to multiple zeitgeber for one tidal cycle on the shore. Increasing the number of tidal cycles four?fold did not significantly increase entrainment or rhythmicity nor was entrainment enhanced by exposure to spring tides compared

S. J. Northcott; R. N. Gibson; E. Morgan

1991-01-01

444

Astrofsica Extragalctica y Cosmologa. Problemas y preguntas clave I.  

E-print Network

relación liga al corrimiento al rojo con el factor de escala del universo. 7. Dadas 3 galaxias A=1, en promedio, su altura se habría incrementado un factor 2 d. La galaxia Andrómeda está un factor 2 más alejada e. La galaxia Andrómeda está un factor ½ menos alejada f. La distancia Vía Láctea

Aretxaga, Itziar

445

La Gaceta de la RSME, Vol. 16 (2013), Nm. 4, Pgs. 761775 761 Mirando hacia el futuro  

E-print Network

está en continua expansión. En algún lugar de este universo hay una galaxia que se llama Matemáticas. Pero cuando se trata de un viaje a otra estrella, por no decir a otra galaxia, son muy perezosos y siempre encuentran excusas para no ir. Sin embargo, en la galaxia de Matemáticas también hay varios

Jaikin Zapirain, Andrés

446

GENERADOR DE IMGENES DE MICROONDAS ESTUDIA LA "PRIMERA LUZ" DEL UNIVERSO  

E-print Network

energía que posteriormente evolucionarían para formar cúmulos de cientos de galaxias. Las mediciones científicos". "Por primera vez hemos observado las semillas que dieron lugar a los cúmulos de galaxias, lo que ha permitido dar una base firme a las teorías de formación de las galaxias" indicó Anthony Readhead

Readhead, Anthony

447

Astrofsica Extragalctica y Cosmologa. Problemas y preguntas clave I.  

E-print Network

criterios de Abell para definir un cúmulo de galaxias? 2. ¿Cuál es la diferencia principal entre cúmulos ricos y pobres? 3. En un cúmulo rico de galaxias ¿Cuál es la componente dominante de materia? ¿Las galaxias? ¿El gas intracúmulo? ¿O alguna otra forma de materia? 4. ¿Qué dispersión de velocidades se puede

Aretxaga, Itziar

448

Introduced brown trout alter native acanthocephalan infections in native fish.  

PubMed

1. Native parasite acquisition provides introduced species with the potential to modify native host-parasite dynamics by acting as parasite reservoirs (with the 'spillback' of infection increasing the parasite burdens of native hosts) or sinks (with the 'dilution' of infection decreasing the parasite burdens of native hosts) of infection. 2. In New Zealand, negative correlations between the presence of introduced brown trout (Salmo trutta) and native parasite burdens of the native roundhead galaxias (Galaxias anomalus) have been observed, suggesting that parasite dilution is occurring. 3. We used a multiple-scale approach combining field observations, experimental infections and dynamic population modelling to investigate whether native Acanthocephalus galaxii acquisition by brown trout alters host-parasite dynamics in native roundhead galaxias. 4. Field observations demonstrated higher infection intensity in introduced trout than in native galaxias, but only small, immature A. galaxii were present in trout. Experimental infections also demonstrated that A. galaxii does not mature in trout, although parasite establishment and initial growth were similar in the two hosts. Taken together, these results support the hypothesis that trout may serve as an infection sink for the native parasite. 5. However, dynamic population modelling predicts that A. galaxii infections in native galaxias should at most only be slightly reduced by dilution in the presence of trout. Rather, model exploration indicates parasite densities in galaxias are highly sensitive to galaxias predation on infected amphipods, and to relative abundances of galaxias and trout. Hence, trout presence may instead reduce parasite burdens in galaxias by either reducing galaxias density or by altering galaxias foraging behaviour. PMID:21426342

Paterson, Rachel A; Townsend, Colin R; Poulin, Robert; Tompkins, Daniel M

2011-09-01

449

2011:InstitutodeAstronoma,UNAM-XIIILatinAmericanRegionalIAUMeeting Ed.W.J.Henney&S.Torres-Peimbert  

E-print Network

´amicas con el fin de estudiar la distribuci´on de masa en SL2S J02140-0535. Este grupo de galaxias a z = 0´on de lentes a escala de grupos de galaxias. Nuestro an´alisis de lente fuerte est´a basado en im

Paris-Sud XI, Université de

450

SciencewiththeGTC10-mTelescope(Granada,Espaa,5-8febrero2002) Editors:JosMiguelRodrguezEspinosa,FranciscoGarznLpez&VernicaMeloMartn  

E-print Network

´on estelar G29.96-0.02 del interior de la galaxia. Las im´agenes son del telescopio de 8 metros de Gemini´on muestra que los n´cleos calientes de la parte interior de la galaxia ya se pueden observar en la regi

De Buizer, James Michael

451

ESTUDIAR ASTRONOMA EN Muchos estudiantes se preguntan el cmo pueden estudiar Astronoma  

E-print Network

interestelar, galaxias y materia intergaláctica. Estamos también involucrados en el proyecto Cosmovisión" en el Evolución de Galaxias" y "Cosmología Observacional". En 1998 el DA junto con el Instituto de Física de la UG

Rodriguez, Luis F.

452

avance y PERSPECTIVA QU LE FALTA AL UNIVERSO?  

E-print Network

que nuestra galaxia no agota las dimensiones de éste. Sabemos que el Universo tuvo un origen, el big planetas del sistema solar, incluyendo el movimiento del Sol y el de la galaxia como un todo (gravitación

Rosas-Ortiz, Jose Oscar

453

PELLCULES ***** obra mestra  

E-print Network

perros (1983) I * La guerra de las galaxias (1977) IIII **** ET (1982) IIII *** Evasión o victoria (1981) I ** Cita a ciegas (1987) I * La loca guerra de las galaxias (1987) II * El corazón del ángel (1987

Márquez-Carreras, David

454

Problemas de Procesos Radiativos 3 Entregar el martes 20 de abril del 2004  

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mediciones hechas en 1994 de la emisi´on de ondas de radio de una fuente dentro de nuestra galaxia. El galaxia. 2 #12; ¡ ¡ ¢¡¢¢¡¢ ££¤¤ O R v v A 2 1 1 2 Figure 2: Si los dos objetos tienen la misma rapidez

Rodriguez, Luis F.

455

Haldane's rule in the 21st century M Schilthuizen1,2  

E-print Network

and crickets), Teleostei (bony fish) and certain Amphibia (amphibians), and with female heterogamety is applied, HR is generally adhered to: at least seven phylogenetically independent origins are known. Given

Dean, Matthew D.

456

484 Fishery Bulletin 106(4) Fishery Bulletin Index  

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(Jordan and Evermann, 1898) (Teleostei: Scorpaeniformes), by James W. Orr and Sharon Hawkins 135 coelestis), by Michael J. Kingsford, Heather M. Patterson, and Matthew J. Flood 143 Seasonal, diel, by Kyle W. Shertzer, Michael H. Prager

457

Transactions of the American Fisheries Society 134:641652, 2005 [Article]Copyright by the American Fisheries Society 2005  

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nigro- maculatus, bluegill Lepomis macrochirus, golden shiner Notemigonus crysoleucas, green sunfish L. cyanellus, largemouth bass Micropterus salmoides, pumpkinseed L. gibbosus, rainbow trout O. mykiss, warmouth

Bonar, Scott A.

458

Morphology, ultrastructure, genetics, and morphometrics of Diplostomum sp. (Digenea: Diplostomidae) metacercariae infecting the European flounder, Platichthys flesus (L.) (Teleostei: Pleuronectidae), off the northwest coast of Portugal  

Microsoft Academic Search

The morphology, ultrastructure, genetics, and morphometrics of a species of Diplostomum von Nordmann 1832 (Digenea: Diplostomidae), isolated from the European flounder (Platichthys flesus (L.)) caught off the northwest coast of Portugal, are characterized. The metacercarial stage was found unencysted in the\\u000a lens capsule of the eye. Light microscopical observations revealed the existence of some variability in specimen shape and\\u000a size,

Francisca I. Cavaleiro; Susana Pina; Fernanda Russell-Pinto; Pedro Rodrigues; Nuno E. Formigo; David I. Gibson; Maria J. Santos

459

Morphology, ultrastructure, genetics, and morphometrics of Diplostomum sp. (Digenea: Diplostomidae) metacercariae infecting the European flounder, Platichthys flesus (L.) (Teleostei: Pleuronectidae), off the northwest coast of Portugal.  

PubMed

The morphology, ultrastructure, genetics, and morphometrics of a species of Diplostomum von Nordmann 1832 (Digenea: Diplostomidae), isolated from the European flounder (Platichthys flesus (L.)) caught off the northwest coast of Portugal, are characterized. The metacercarial stage was found unencysted in the lens capsule of the eye. Light microscopical observations revealed the existence of some variability in specimen shape and size, with two morphotypes, referred to as "round" and "long", being apparent. Scanning electron microscopy revealed a smooth, unarmed tegument, with the lappet region being the most irregular and porose. Both the oral and ventral suckers were provided with a series of papillae, which presented very distinctive ultrastructural features and were particularly conspicuous in the case of the ventral sucker. The two morphotypes detected were found to have 100% genetic correspondence in the 18S?+?ITS1?+?5.8S region of the rDNA. Since the genetic data for this metacercaria differed from those of the species of Diplostomum available in GenBank, a description of a new genotype (accession number GQ370809) is provided. The molecular phylogenetic analyses, in conjunction with principal components and cluster analyses based on morphometric data, revealed the existence of consistent differences between the Diplostomum sp. metacercariae from flounder compared with Diplostomum spathaceum, Diplostomum mergi, Diplostomum pseudospathaceum, and Diplostomum paracaudum. The latter of these species was found to be the most similar to the present material. Our results do not support an evolutionary separation of the European and North American species of Diplostomum. PMID:21626424

Cavaleiro, Francisca I; Pina, Susana; Russell-Pinto, Fernanda; Rodrigues, Pedro; Formigo, Nuno E; Gibson, David I; Santos, Maria J

2012-01-01