Population Dynamics and Diet of the Madamango Sea Catfish Cathorops spixii (Agassiz, 1829) (Siluriformes: Ariidae) in a Tropical Bight in Southeastern Brazil

PubMed Central

Denadai, Márcia; Pombo, Maíra; Santos, Flávia Borges; Bessa, Eduardo; Ferreira, Adriana; Turra, Alexander

2013-01-01

The madamango sea catfish, Cathorops spixii (Siluriformes: Ariidae), is often among the most abundant fishes on the South American Atlantic coast. In the present study, conducted in shallow, non-estuarine coastal areas of Caraguatatuba Bight in southeastern Brazil, collections of this species, the most abundant member of the ichthyofauna, included primarily medium-sized individuals, indicating that the area may play a specific role in their development. Although studies of the local ichthyofauna have been much neglected, the area is economically important and its ecological significance is undervalued. This study primarily treats habitat use by C. spixii, assessing certain population parameters and the dietary composition. Monthly samples were taken from August 2003 through October 2004, with three trawls in two areas, corresponding to depths of about 1 to 4 m. The catfish showed two main peaks of abundance in the area, in April/May and July 2004. A mode around 9 cm SL persisted through time, and the entrance of younger recruits peaked from January to April. The low estimate for body-growth parameters (K = 0.16) corroborates some K-strategist characteristics of the species. The asymptotic length was 27.3 cm SL and total mortality (Z) was 1.01 yr−1. Cathorops spixii showed an omnivorous feeding habit, preying mainly upon polychaetes, copepods and bivalves, with considerable seasonality in its diet. PMID:24282575

Genetic and Morphological Analyses Demonstrate That Schizolecis guntheri (Siluriformes: Loricariidae) Is Likely to Be a Species Complex

PubMed Central

Souza, Camila S.; Costa-Silva, Guilherme J.; Roxo, Fábio F.; Foresti, Fausto; Oliveira, Claudio

2018-01-01

Schizolecis is a monotypic genus of Siluriformes widely distributed throughout isolated coastal drainages of southeastern Brazil. Previous studies have shown that fish groups found in isolated river basins tend to differentiate over time in the absence of gene flow, resulting in allopatric speciation. In this study, we used partial sequences of the mitochondrial gene COI with the analysis of the General Mixed Yule Coalescent model (GMYC) and the Automatic Barcode Gap Discovery (ABGD) for single locus species delimitation, and a Principal Component Analysis (PCA) of external morphology to test the hypothesis that Schizolecis guntheri is a complex of species. We analyzed 94 samples of S. guntheri for GMYC and ABGD, and 82 samples for PCA from 22 coastal rivers draining to the Atlantic in southeastern Brazil from the Paraná State to the north of the Rio de Janeiro State. As a result, the GMYC model and the ABGD delimited five operational taxonomy units (OTUs – a nomenclature referred to in the present study of the possible new species delimited for the genetic analysis), a much higher number compared to the traditional alfa taxonomy that only recognizes S. guntheri across the isolated coastal rivers of Brazil. Furthermore, the PCA analysis suggests that S. guntheri is highly variable in aspects of external body proportions, including dorsal-fin spine length, pectoral-fin spine length, pelvic-fin spine length, lower caudal-fin spine length, caudal peduncle depth, anal width and mandibular ramus length. However, no exclusive character was found among the isolated populations that could be used to describe a new species of Schizolecis. Therefore, we can conclude, based on our results of PCA contrasting with the results of GMYC and ABGD, that S. guntheri represents a complex of species. PMID:29552028

Genetic and Morphological Analyses Demonstrate That Schizolecis guntheri (Siluriformes: Loricariidae) Is Likely to Be a Species Complex.

PubMed

Souza, Camila S; Costa-Silva, Guilherme J; Roxo, Fábio F; Foresti, Fausto; Oliveira, Claudio

2018-01-01

Schizolecis is a monotypic genus of Siluriformes widely distributed throughout isolated coastal drainages of southeastern Brazil. Previous studies have shown that fish groups found in isolated river basins tend to differentiate over time in the absence of gene flow, resulting in allopatric speciation. In this study, we used partial sequences of the mitochondrial gene COI with the analysis of the General Mixed Yule Coalescent model (GMYC) and the Automatic Barcode Gap Discovery (ABGD) for single locus species delimitation, and a Principal Component Analysis (PCA) of external morphology to test the hypothesis that Schizolecis guntheri is a complex of species. We analyzed 94 samples of S. guntheri for GMYC and ABGD, and 82 samples for PCA from 22 coastal rivers draining to the Atlantic in southeastern Brazil from the Paraná State to the north of the Rio de Janeiro State. As a result, the GMYC model and the ABGD delimited five operational taxonomy units (OTUs - a nomenclature referred to in the present study of the possible new species delimited for the genetic analysis), a much higher number compared to the traditional alfa taxonomy that only recognizes S. guntheri across the isolated coastal rivers of Brazil. Furthermore, the PCA analysis suggests that S. guntheri is highly variable in aspects of external body proportions, including dorsal-fin spine length, pectoral-fin spine length, pelvic-fin spine length, lower caudal-fin spine length, caudal peduncle depth, anal width and mandibular ramus length. However, no exclusive character was found among the isolated populations that could be used to describe a new species of Schizolecis . Therefore, we can conclude, based on our results of PCA contrasting with the results of GMYC and ABGD, that S. guntheri represents a complex of species.

Blood flukes (Digenea: Aporocotylidae) of walking catfishes (Siluriformes: Clariidae): new genus and species from the Mekong River (Vietnam) with comments on related catfish aporocotylids.

PubMed

Truong, Triet Nhat; Bullard, Stephen A

2013-07-01

Nomasanguinicola canthoensis gen. et sp. n. infects the branchial vessels of bighead catfish, Clarias macrocephalus Günther (Siluriformes: Clariidae), in the Mekong River near Can Tho, southern Vietnam. Nomasanguinicola differs from all other genera of fish blood flukes (Digenea: Aporocotylidae) by the combination of lacking body spines and by having an anterior sucker with two flanking columns of large denticles, an intestine comprising several short papilla-like caeca, an inverse U-shaped uterus, and an ootype located near the separate genital pores. The new species has an ootype that is posterior to the level of the female genital pore. That feature most easily differentiates it from the only other putative aporocotylid species having an anterior sucker with two flanking columns of large denticles, Plehniella dentata Paperna, 1964 and Sanguinicola clarias Imam, Marzouk, Hassan et Itman, 1984, which have an ootype that is lateral (P. dentata) or anterior (S. clarias) to the level of the female genital pore. These two species apparently lack extant type materials, infect North African catfish, Clarias gariepinus (Burchell), and herein are considered incertae sedis, but likely comprise species of Nomasanguinicola. An updated list of hosts, sites of infection and geographic localities for the six species and three genera of blood flukes that mature in catfishes is provided. The new species is the first fish blood fluke recorded from Vietnam and only the third reported from a walking catfish (Clariidae).

A morphological and molecular study of two species of Raphidascaroides Yamaguti, 1941 (Nematoda: Anisakidae), parasites of doradid catfish (Siluriformes) in South America, with a description of R. moraveci n. sp.

PubMed

Pereira, Felipe B; Tavares, Luiz E R; Scholz, Tomáš; Luque, José L

2015-05-01

Nematodes of the genus Raphidascaroides Yamaguti, 1941 parasitising doradid catfishes (Siluriformes: Doradidae) in Brazil were studied based on morphological and molecular evaluation of newly collected material. A new species, Raphidascaroides moraveci n. sp., is described from the intestine of Platydoras armatulus (Valenciennes) from River Miranda, River Paraguay basin, Pantanal, Mato Grosso do Sul. The new species differs from all of the congeners in having short spicules (163-217 μm in length) representing less than 1% of the total body length and in the posterior region of cloacal opening covered by small rudimentary spines. In addition, it differs from the other congeneric species in the number and arrangement of the caudal papillae and the structure of lips and tail. Raphidascaroides moraveci n. sp. is the third species described from freshwater fishes and the second one in the Neotropical Region. New morphological data on R. brasiliensis Moravec & Thatcher, 1997 from Megalodoras uranoscopus (Eigenmann & Eigenmann) and Platydoras costatus (Linnaeus) (both new host records) from River Xingu, River Amazon basin, Pará, are provided including scanning electron micrographs of taxonomically important structures. The differentiation of the new species is supported by molecular data (partial sequences of the small and large subunits of the rRNA gene).

A new genus and species of marine catfishes (Siluriformes; Ariidae) from the upper Eocene Birket Qarun Formation, Wadi El-Hitan, Egypt.

PubMed

El-Sayed, Sanaa E; Kora, Mahmoud A; Sallam, Hesham M; Claeson, Kerin M; Seiffert, Erik R; Antar, Mohammed S

2017-01-01

Wadi El-Hitan, the UNESCO World Heritage Site, of the Fayum Depression in the northeast part of the Western Desert of Egypt, has produced a remarkable collection of Eocene vertebrates, in particular the fossil whales from which it derives its name. Here we describe a new genus and species of marine catfishes (Siluriformes; Ariidae), Qarmoutus hitanensis, from the base of the upper Eocene Birket Qarun Formation, based on a partial neurocranium including the complete left side, partial right dentary, left suspensorium, two opercles, left pectoral girdle and spine, nuchal plates, first and second dorsal spines, Weberian apparatus and a disassociated series of abdominal vertebrae. All of the elements belong to the same individual and some of them were found articulated. Qarmoutus gen. nov. is the oldest and the most complete of the Paleogene marine catfishes unearthed from the Birket Qarun Formation. The new genus exhibits distinctive features not seen in other African Paleogene taxa, such as different sculpturing on the opercle and pectoral girdle with respect to that on the neurocranium and nuchal plates, denticulate ornamentation on the skull bones arranged in longitudinal rows and forming a radiating pattern on the sphenotic, pterotic, extrascapular and the parieto-supraoccipital, indentations or pitted ornamentation on the nuchal plates as well as the parieto-supraoccipital process, strut-like radiating pattern of ornamentation on the opercle from the proximal articulation to margins, longitudinal, curved, reticulate ridges and tubercular ornamentations on the cleithrum, sinuous articulation between the parieto-supraoccipital process and the anterior nuchal plate, long, narrow, and arrowhead shaped nuchal shield, very small otic capsules restricted to the prootic. Multiple parsimony and Bayesian morphological phylogenetic analyses of Ariidae, run with and without "molecular scaffolds", yield contradictory results for the placement of Qarmoutus; the genus is either

Diel variation of larval fish abundance in the Amazon and Rio Negro.

PubMed

Araujo-Lima, C A; da Silva, V V; Petry, P; Oliveira, E C; Moura, S M

2001-08-01

Many streams and large rivers present higher ichthyoplankton densities at night. However, in some rivers this does not occur and larvae are equally abundant during the day. Larval drift diel variation is an important information for planning sampling programs for evaluating larval distribution and production. The aim of this study was to test whether the abundance of larval fish was different at either period. We tested it by comparing day and night densities of characiform, clupeiform and siluriform larvae during five years in the Amazon and one year in Rio Negro. We found that larvae of three species of characiform and larvae of siluriform were equally abundant during day and night in the Amazon. Conversely, the catch of Pellona spp. larvae was significantly higher during the day. In Rio Negro, however, larval abundance was higher during the night. These results imply that day samplings estimate adequately the abundance of these characiform and siluriform larvae in the Amazon, but not Pellona larvae. Evaluations of larved densities of Rio Negro will have to consider night sampling.

A new genus and species of marine catfishes (Siluriformes; Ariidae) from the upper Eocene Birket Qarun Formation, Wadi El-Hitan, Egypt

PubMed Central

2017-01-01

Wadi El-Hitan, the UNESCO World Heritage Site, of the Fayum Depression in the northeast part of the Western Desert of Egypt, has produced a remarkable collection of Eocene vertebrates, in particular the fossil whales from which it derives its name. Here we describe a new genus and species of marine catfishes (Siluriformes; Ariidae), Qarmoutus hitanensis, from the base of the upper Eocene Birket Qarun Formation, based on a partial neurocranium including the complete left side, partial right dentary, left suspensorium, two opercles, left pectoral girdle and spine, nuchal plates, first and second dorsal spines, Weberian apparatus and a disassociated series of abdominal vertebrae. All of the elements belong to the same individual and some of them were found articulated. Qarmoutus gen. nov. is the oldest and the most complete of the Paleogene marine catfishes unearthed from the Birket Qarun Formation. The new genus exhibits distinctive features not seen in other African Paleogene taxa, such as different sculpturing on the opercle and pectoral girdle with respect to that on the neurocranium and nuchal plates, denticulate ornamentation on the skull bones arranged in longitudinal rows and forming a radiating pattern on the sphenotic, pterotic, extrascapular and the parieto-supraoccipital, indentations or pitted ornamentation on the nuchal plates as well as the parieto-supraoccipital process, strut-like radiating pattern of ornamentation on the opercle from the proximal articulation to margins, longitudinal, curved, reticulate ridges and tubercular ornamentations on the cleithrum, sinuous articulation between the parieto-supraoccipital process and the anterior nuchal plate, long, narrow, and arrowhead shaped nuchal shield, very small otic capsules restricted to the prootic. Multiple parsimony and Bayesian morphological phylogenetic analyses of Ariidae, run with and without “molecular scaffolds”, yield contradictory results for the placement of Qarmoutus; the genus is

Assessing fish assemblages similarity above and below a dam in a neotropical reservoir with partial blockage.

PubMed

Araújo, F G; Santos, A B I; Albieri, R J

2013-11-01

Damming rivers disrupts the water flow and changes the ichthyofauna organisation. We investigated an impoundment with permanent connection and homogeneous environmental conditions between the zones above and below the dam. Temperature was comparatively higher during wet season irrespective of zone, and both zones had higher dissolved oxygen, conductivity and transparency in the dry season. A total of 1687 individuals comprising 27 species were collected in the downriver zone, while the reservoir had 879 individuals and 23 species. Each zone had different fish assemblage composition and structure, but assemblages were not explained by the examined environmental variables (r2 = 0.08; p = 0.307). Migratory species such as Pimelodus maculatus, Pimelodus fur, Leporinus copelandii and Prochilodus lineatus were the most affected, and probably are prevented to perform upriver migrations. On the other hand, lentic adapted species such as G. brasiliensis, Hoplias malabaricus and Hoplosternum littorale successfully colonised the reservoir. Therefore we conclude that the presence of the lateral hydrological connectivity alone does not guarantee the ecological connectivity since fish assemblage similarity differed between the two zones. Fish passage facilities should be monitored and managed to evaluate and improve their functionality.

Department of Agriculture, Food Safety and Inspection Service

MedlinePlus

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New data on species of Demidospermus (Dactylogyridae: Monogenea) parasitizing fishes from the reservoir of the Itaipu Hydroelectric Power Station, Paraná State, Brazil, with new synonymies.

PubMed

Cohen, Simone C; Kohn, Anna

2008-01-01

Eight known species of Demidospermus (Dactylogyridae, Monogenea) were collected from siluriform fishes from reservoir of the Itaipu Hydroelectric Power Station, Paraná, Brazil. Four of them are recorded for the first time in Brazil, enlarging their geographical distribution: Demidospermus armostus, Demidospermus anus, Demidospermus bidiverticulatum and Demidospermus valenciennesi. Demidospermus labrosi is synonymized with Demidospermus cornicinus and Demidospermus mandi with Demidospermus leptosynophallus and reported from two new hosts. Demidospermus paravalenciennesi and Demidospermus uncusvalidus were also collected.

Structural features of cytochrome P450 1A associated with the absence of EROD activity in liver of the of the loricariid catfish Pterygoplichthys sp

PubMed Central

Parente, T.E.M.; Rebelo, M.F.; da-Silva, M.L.; Woodin, B.R.; Goldstone, J. V.; Bisch, P.M.; Paumgartten, F.J.R.; Stegeman, J.J.

2011-01-01

The Amazon catfish genus Pterygoplichthys (Loricariidae, Siluriformes) is closely related to the loricariid genus Hypostomus, in which at least two species lack detectable ethoxyresorufin-O-deethylase (EROD) activity, typically catalyzed by cytochrome P450 1 (CYP1) enzymes. Pterygoplichthys sp. liver microsomes also lacked EROD, as well as activity with other substituted resorufins, but aryl hydrocarbon receptor agonists induced hepatic CYP1A mRNA and protein suggesting structural/functional differences in Pterygoplichthys CYP1s from those in other vertebrates. Comparing the sequences of CYP1As of Pterygoplichthys sp. and of two phylogenetically-related siluriform species that do catalyze EROD (Ancistrus sp., Loricariidae and Corydoras sp., Callichthyidae) showed that these three proteins share amino acids at 17 positions that are not shared by any fish in a set of 24 other species. Pterygoplichthys and Ancistrus (the loricariids) have an additional 22 amino acid substitutions in common that are not shared by Corydoras or by other fish species. Pterygoplichthys has six exclusive amino acid substitutions. Molecular docking and dynamics simulations indicate that Pterygoplichthys CYP1A has a weak affinity for ER, which binds infrequently in a productive orientation, and in a less stable conformation than in CYP1As of species that catalyze EROD. ER also binds with the carbonyl moiety proximal to the heme iron. Pterygoplichthys CYP1A has amino acids substitutions that reduce the frequency of correctly oriented ER in the AS preventing the detection of EROD activity. The results indicate that loricariid CYP1As may have a peculiar substrate selectivity that differs from CYP1As of most vertebrates. PMID:21840383

Structural features of cytochrome P450 1A associated with the absence of EROD activity in liver of the loricariid catfish Pterygoplichthys sp.

PubMed

Parente, Thiago E M; Rebelo, Mauro F; da-Silva, Manuela L; Woodin, Bruce R; Goldstone, Jared V; Bisch, Paulo M; Paumgartten, Francisco J R; Stegeman, John J

2011-12-10

The Amazon catfish genus Pterygoplichthys (Loricariidae, Siluriformes) is closely related to the loricariid genus Hypostomus, in which at least two species lack detectable ethoxyresorufin-O-deethylase (EROD) activity, typically catalyzed by cytochrome P450 1 (CYP1) enzymes. Pterygoplichthys sp. liver microsomes also lacked EROD, as well as activity with other substituted resorufins, but aryl hydrocarbon receptor agonists induced hepatic CYP1A mRNA and protein suggesting structural/functional differences in Pterygoplichthys CYP1s from those in other vertebrates. Comparing the sequences of CYP1As of Pterygoplichthys sp. and of two phylogenetically related siluriform species that do catalyze EROD (Ancistrus sp., Loricariidae and Corydoras sp., Callichthyidae) showed that these three proteins share amino acids at 17 positions that are not shared by any fish in a set of 24 other species. Pterygoplichthys and Ancistrus (the loricariids) have an additional 22 amino acid substitutions in common that are not shared by Corydoras or by other fish species. Pterygoplichthys has six exclusive amino acid substitutions. Molecular docking and dynamics simulations indicate that Pterygoplichthys CYP1A has a weak affinity for ER, which binds infrequently in a productive orientation, and in a less stable conformation than in CYP1As of species that catalyze EROD. ER also binds with the carbonyl moiety proximal to the heme iron. Pterygoplichthys CYP1A has amino acid substitutions that reduce the frequency of correctly oriented ER in the AS preventing the detection of EROD activity. The results indicate that loricariid CYP1As may have a peculiar substrate selectivity that differs from CYP1As of most vertebrate. Copyright © 2011 Elsevier B.V. All rights reserved.

Rhabdochona longleyi sp. n. (Nematoda: Rhabdochonidae) from blind catfishes, Trogloglanis pattersoni and Satan eurystomus (Ictaluridae) from the subterranean waters of Texas.

PubMed

Moravec, F; Huffman, D G

1988-01-01

A new nematode species, Rhabdochona longleyi sp. n. is described from the intestine of two species of blind catfishes, Trogloglanis pattersoni Eigenmann (type host) and Satan eurystomus Hubbs et Bailey (both fam. Ictaluridae, Siluriformes) from the subterranean waters (artesian wells penetrating San Antonio pool of Edwards Aquifer) of Texas, USA. It is characterized largely by the presence of only six anterior teeth in the prostom, simple deirids, by the shape and length of spicules (0.42 to 0.50 mm and 0.093-0.102 mm), shape of the tail tip (rounded), and by filamented eggs. R. longleyi probably adapted to the environment of the aquifer by utilizing available troglobitic crustaceans instead of aquatic insects as an intermediate host.

The species of Hemiancistrus (Siluriformes: Loricariidae) from Ecuador.

PubMed

Provenzano R, Francisco; Barriga S, Ramiro

2017-05-29

At the Fish Collection of the Instituto de Ciencias Biológicas, Escuela Politécnica Nacional, Quito, three species traditionally grouped in the genus Hemiancistrus were identified: H. annectens (Regan 1904), H. landoni Eigenmann 1916, and a new specie described here. The new species inhabits exclusively in the Esmeraldas River Basin, Pacific slope, northwestern Ecuador. It is easily recognized by the completely naked abdomen, with rounded, dark spots, and a different color pattern on the dorsal and caudal fins. A comparative analysis of bones related to the opercular mobility, shows important differences between H. annectens, H. landoni, and the new species, suggesting that H. annectens does not belong to the genus Hemiancistrus or the Ancistrini group. According to the characteristics observed in these bones, H. annectens shows greater similarity to those reported in species of the Hypostomini group, supporting its inclusion in this group, but placing it in the genus Hypostomus requires further analysis. On the other hand, the conditions observed on the bones of Hemiancistrus landoni and the new species suggest that both are inside of the Ancistrini group. The new species is placed in the genus Hemiancistrus tentatively, pending future analysis.

Cytogenetic analysis of five Hypostomus species (Siluriformes, Loricariidae)

PubMed Central

Martinez, Emanuel Ricardo Monteiro; Zawadzki, Claudio Henrique; Foresti, Fausto; Oliveira, Claudio

2011-01-01

In this work, we analyzed the karyotypes of five Hypostomus species. Hypostomus cf. heraldoi, from the Mogi-Guaçu River, had 2n = 72 chromosomes, with a nucleolar organizer region (NOR) in one chromosomal pair. Hypostomus regani, from the Mogi-Guaçu River had 2n = 72 chromosomes with NORs in two chromosomal pairs. Hypostomus sp., from the Mogi-Guaçu River basin, had 2n = 68 chromosomes, with NORs in two chromosomal pairs. Hypostomus aff. agna, from Cavalo Stream, had 2n = 74 chromosomes with NORs in two chromosomal pairs. Hypostomus cf. topavae, from Carrapato Stream, had 2n = 80 chromosomes, with NORs in two chromosomal pairs. Hypostomus species showed marked diversity in the karyotypic formula, which suggested the occurrence of several Robertsonian rearrangements and pericentric inversions during the evolutionary history of this genus. This hypothesis was supported by the occurrence of a large number of uniarmed chromosomes and multiple NORs in a terminal position in most species and may be a derived condition in the Loricariidae. PMID:22215958

Factors influencing movement of two migratory fishes within the tailrace of a large neotropical dam and their implications for hydropower impacts

USGS Publications Warehouse

Suzuki, F. M.; Dunham, Jason B.; Silva, L. G. M.; Alves, C. B. M.; Pompeu, P.S.

2017-01-01

Fish attempting to move upstream through hydroelectric dams can be trapped and killed in turbines. Understanding fish movement patterns can provide useful insights for how to manage dam operations to minimize fish kill in turbines. We evaluated the movements of two migratory fish (Curimba-Prochilodus argenteus and Mandi-Pimelodus maculatus) using acoustic telemetry in the tailrace of Três Marias Dam (São Francisco River, Brazil) from 31 October 2011 to 16 February 2012. The majority of tagged fish left the tailrace in less than one week; however, some individuals returned, performing several visits to the tailrace. Mandi remained longer in the tailrace than Curimba. The number of visits was influenced by diel period, turbine and spillway discharge. Although the diel period was the only important contributor to the visits performed by Curimba, the movements of Mandi were significantly influenced by three factors. We found that whereas Curimba was predominantly diurnal, Mandi showed nocturnal habits. Additionally, visits of Mandi were significantly greater during higher turbine and spillway discharge. We discuss the implications of these results for understanding fish movements in the Três Marias Dam tailrace and their potential implications for adapting hydroelectric operations to minimize fish kills.

Evolutionary history of Otophysi (Teleostei), a major clade of the modern freshwater fishes: Pangaean origin and Mesozoic radiation

PubMed Central

2011-01-01

Background Freshwater harbors approximately 12,000 fish species accounting for 43% of the diversity of all modern fish. A single ancestral lineage evolved into about two-thirds of this enormous biodiversity (≈ 7900 spp.) and is currently distributed throughout the world's continents except Antarctica. Despite such remarkable species diversity and ubiquity, the evolutionary history of this major freshwater fish clade, Otophysi, remains largely unexplored. To gain insight into the history of otophysan diversification, we constructed a timetree based on whole mitogenome sequences across 110 species representing 55 of the 64 families. Results Partitioned maximum likelihood analysis based on unambiguously aligned sequences (9923 bp) confidently recovered the monophyly of Otophysi and the two constituent subgroups (Cypriniformes and Characiphysi). The latter clade comprised three orders (Gymnotiformes, Characiformes, Siluriformes), and Gymnotiformes was sister to the latter two groups. One of the two suborders in Characiformes (Characoidei) was more closely related to Siluriformes than to its own suborder (Citharinoidei), rendering the characiforms paraphyletic. Although this novel relationship did not receive strong statistical support, it was supported by analyzing independent nuclear markers. A relaxed molecular clock Bayesian analysis of the divergence times and reconstruction of ancestral habitats on the timetree suggest a Pangaean origin and Mesozoic radiation of otophysans. Conclusions The present timetree demonstrates that survival of the ancestral lineages through the two consecutive mass extinctions on Pangaea, and subsequent radiations during the Jurassic through early Cretaceous shaped the modern familial diversity of otophysans. This evolutionary scenario is consistent with recent arguments based on biogeographic inferences and molecular divergence time estimates. No fossil otophysan, however, has been recorded before the Albian, the early Cretaceous 100

Evolutionary history of Otophysi (Teleostei), a major clade of the modern freshwater fishes: Pangaean origin and Mesozoic radiation.

PubMed

Nakatani, Masanori; Miya, Masaki; Mabuchi, Kohji; Saitoh, Kenji; Nishida, Mutsumi

2011-06-22

Freshwater harbors approximately 12,000 fish species accounting for 43% of the diversity of all modern fish. A single ancestral lineage evolved into about two-thirds of this enormous biodiversity (≈ 7900 spp.) and is currently distributed throughout the world's continents except Antarctica. Despite such remarkable species diversity and ubiquity, the evolutionary history of this major freshwater fish clade, Otophysi, remains largely unexplored. To gain insight into the history of otophysan diversification, we constructed a timetree based on whole mitogenome sequences across 110 species representing 55 of the 64 families. Partitioned maximum likelihood analysis based on unambiguously aligned sequences (9923 bp) confidently recovered the monophyly of Otophysi and the two constituent subgroups (Cypriniformes and Characiphysi). The latter clade comprised three orders (Gymnotiformes, Characiformes, Siluriformes), and Gymnotiformes was sister to the latter two groups. One of the two suborders in Characiformes (Characoidei) was more closely related to Siluriformes than to its own suborder (Citharinoidei), rendering the characiforms paraphyletic. Although this novel relationship did not receive strong statistical support, it was supported by analyzing independent nuclear markers. A relaxed molecular clock Bayesian analysis of the divergence times and reconstruction of ancestral habitats on the timetree suggest a Pangaean origin and Mesozoic radiation of otophysans. The present timetree demonstrates that survival of the ancestral lineages through the two consecutive mass extinctions on Pangaea, and subsequent radiations during the Jurassic through early Cretaceous shaped the modern familial diversity of otophysans. This evolutionary scenario is consistent with recent arguments based on biogeographic inferences and molecular divergence time estimates. No fossil otophysan, however, has been recorded before the Albian, the early Cretaceous 100-112 Ma, creating an over 100

Molecular phylogeny of the armored catfish family Callichthyidae (Ostariophysi, Siluriformes).

PubMed

Shimabukuro-Dias, Cristiane Kioko; Oliveira, Claudio; Reis, Roberto E; Foresti, Fausto

2004-07-01

The family Callichthyidae comprises eight genera of fishes widely distributed across the Neotropical region. In the present study, sequences of the mitochondrial genes 12S rRNA, 16S rRNA, ND4, tRNAHis, and tRNASer were obtained from 28 callichthyid specimens. The sample included 12 species of Corydoras, three species of Aspidoras, two species of Brochis, Dianema, Lepthoplosternum, and Megalechis, and two local populations of Callichthys and Hoplosternum. Sequences of Nematogenys inermis (Nematogenyidae), Trichomycterus areolatus, and Henonemus punctatus (Trichomycteridae), Astroblepus sp. (Astroblepidae), and Neoplecostomus paranensis, Delturus parahybae, and Hemipsilichthys nimius (Loricariidae) were included as the outgroup. Phylogenetic analyses were performed by using the methods of maximum parsimony and maximum likelihood. The results of almost all analyses were very similar. The family Callichthyidae is monophyletic and comprises two natural groups: the subfamilies Corydoradinae (Aspidoras, Brochis, and Corydoras) and Callichthyinae (Callichthys, Dianema, Hoplosternum, Lepthoplosternum, and Megalechis), as previously demonstrated by morphological studies. The relationships observed within these subfamilies are in several ways different from those previously proposed on the basis of morphological data. Molecular results were compared with the morphologic and cytogenetic data available on the family. Copyright 2003 Elsevier Inc.

Histochemical differences along the intestine of Corydoras paleatus (Siluriformes: Callichthyidae).

PubMed

Plaul, Silvia E; Barbeito, Claudio G; Díaz, Alcira O

2016-03-01

The Neotropical catfish Corydoras paleatus is a facultative air-breather and the caudal half of the intestine is involved in gas exchange. In South America, air-breathing fishes are found in tropical or sub-tropical freshwaters where the probability of hypoxia is high. The aim of this study was to characterize by traditional histochemical and lectinhistochemical methods the pattern of carbohydrate in the intestinal mucosa. Intestine samples were taken from 25 healthy adult specimens collected in Buenos Aires (Argentina). Samples were fixed by immersion in 10 % buffered formalin and routinely processed and embedded in paraffin wax. Subsequently, these sections were incubated in the biotinylated lectins battery. Labeled Streptavidin-Biotin (LSAB) system was used for detection, diaminobenzidine as chromogen and haematoxylin as a contrast. To locate and distinguish glycoconjugates (GCs) of the globet cells, we used the following histochemical methods: PAS; PAS*S; KOH/ PA*S; PA/Bh/KOH/PAS; KOH/PA*/Bh/PAS; Alcian Blue and Toluidine Blue at different pHs. Microscopically, the general structure of vertebrate intestine was observed and showed all the cell types characteristic of the intestinal epithelium. The cranial sector of catfish intestine is a site of digestion and absorption and its structure is similar to other fish groups. In contrast, enterocytes of the caudal portion are low cuboidal cells; and between these, globet cells and capillaries are observed, these latter may reach the mucosal lumen. Underlying the epithelium, observed a well-developed lamina propria-submucosa made of connective tissue; this layer was highly vascularized and did not exhibit glands. According to histochemistry, the diverse GCs elaborated and secreted in the intestine are associated with specific functions in relation to their physiological significance, with special reference to their role in lubrication, buffering effect and prevention of proteolytic damage to the epithelium together with other biological processes, such as osmoregulation and ion exchange. The lectinhistochemical analysis of the intestinal mucosa reveals the presence of terminal residues of glucose, mannose and galactose. In conclusion, this study has shown that GCs synthesized in the intestine of C. paleatus exhibit a high level of histochemical complexity and that the lectin binding pattern of the intestinal mucosa is characteristic of each species and the variations are related with the multiple functions performed by the mucus in the digestive tract. The information generated here may be a relevant biological tool for comparing and analyzing the possible glycosidic changes in the intestinal mucus under different conditions, such as changes in diet or different pathological stages.

Ontogeny of the cranial musculature in Corydoras aeneus Callichthyidae, Siluriformes.

PubMed

Huysentruyt, F; Brunain, M; Adriaens, D

2009-11-01

A complete study of the early ontogeny of the cranial muscles of Corydoras aeneus (Callichthyidae) was undertaken and results were compared with those for the loricariid Ancistrus cf. triradiatus. This comparison reveals a high degree of similarity in the ontogeny of both species' cranial muscles. Both species lack a musculus protractor hyoidei, and the musculus intermandibularis posterior is divided into two different parts that have partly obtained a novel function (serving the lower lip) in A. cf. triradiatus. A similar increase in muscular complexity in this species is found in the dorsal constrictor of the hyoid muscle plate. This constrictor gives rise to the same muscles in both C. aeneus and A. cf. triradiatus, but in A. cf. triradiatus the musculus levator operculi later hypertrophies. In C. aeneus the musculus extensor tentaculi forms a single muscle diverging posteriorly, whereas in A. cf. triradiatus the musculus extensor tentaculi differentiates into two separate bundles. Also, a loricariid neoformation is present called the musculus levator tentaculi.

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

PubMed

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

2014-04-01

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

Evolutionary and biogeographic history of the subfamily Neoplecostominae (Siluriformes: Loricariidae)

PubMed Central

Roxo, Fábio F; Zawadzki, Cláudio H; Alexandrou, Markos A; Costa Silva, Guilherme J; Chiachio, Marcio C; Foresti, Fausto; Oliveira, Claudio

2012-01-01

Freshwater fish evolution has been shaped by changes in the earth's surface involving changes in the courses of rivers and fluctuations in sea level. The main objective of this study is to improve our knowledge of the evolution of loricariids, a numerous and adaptive group of freshwater catfish species, and the role of geological changes in their evolution. We use a number of different phylogenetic methods to test the relationships among 52 representative taxa within the Neoplecostominae using 4676 bps of mitochondrial and nuclear DNA. Our analysis revealed that the subfamily Neoplecostominae is monophyletic, including Pseudotocinclus, with three lineages recognized. The first lineage is composed of part of Pareiorhina rudolphi, P. cf. rudolphi, and Pseudotocinclus; the second is composed of Isbrueckerichthys, Pareiorhaphis, Kronichthys, and the species Neoplecostomus ribeirensis; and the third is composed of Pareiorhina carrancas, P. cf. carrancas, Pareiorhina sp. 1, a new genus, and all the species of the genus Neoplecostomus, except N. ribeirensis. The relaxed molecular clock calibration provides a temporal framework for the evolution of the group, which we use for a likelihood-based historical biogeographic analysis to test relevant hypotheses on the formation of southeast Brazil. We hypothesize that headwater capture events and marine regressions have shaped the patterns of distribution within the subfamily Neoplecostominae throughout the distinct basins of southeast Brazil. PMID:23145330

Influence of seasonal, diel, lunar, and other environmental factors on upstream fish passage in the igarapava fish ladder, Brazil

USGS Publications Warehouse

Bizzotto, P.M.; Godinho, Alexandre L.; Vono, V.; Kynard, B.; Godinho, Hugo P.

2009-01-01

Upstream fish passage was evaluated during 12 months in the vertical-slot Igarapava Fish Ladder constructed around Igarapava Dam, in the heavily dammed Grande River, Southeast Brazil. A video monitoring system was used to observe 61,621 fish that passed the ladder, of which 93.5% were identified to 15 taxa. Among the migratory species, the most abundant were Pimelodus maculatus (33.6% of all fish), Leporinus octofasciatus (31.4%), Leporinus friderici (4.5%), and Prochilodus lineatus (3.1%). Seven taxa were classified as nonmigratory, and of these taxa, the small Bryconamericus stramineus was the most abundant (12.7%) of all fishes. Passage of the 'nonmigratory' taxa upstream in the ladder shows they are migratory in this system and have a strong behavioural drive to move to upstream habitat. Passage of most taxa had a strong seasonal pattern. While some species passed primarily during the day, others showed a distinct nocturnal pattern. Lunar phase and water temperature also strongly affected passage of some taxa. Rainfall and dam discharge had a small or null influence on most taxa; perhaps due to the fairly small catchment area of the reservoir and the highly regulated discharge at Igarapava Dam. ?? 2009 John Wiley & Sons A/S.

Electric Organ Discharges of Mormyrid Fish as a Possible Cue for Predatory Catfish

NASA Astrophysics Data System (ADS)

Hanika, S.; Kramer, B.

During reproductive migration the electroreceptive African sharptooth catfish, Clarias gariepinus (Siluriformes), preys mainly on a weakly electric fish, the bulldog Marcusenius macrolepidotus (Mormyridae; Merron 1993). This is puzzling because the electric organ discharges of known Marcusenius species are pulses of a duration (<1ms) too short for being detected by the catfishes' low-frequency electroreceptive system (optimum sensitivity, 10-30Hz Peters and Bretschneider 1981). On the recent discovery that M. macrolepidotus males emit discharges lasting approximately ten times longer than those of females (Kramer 1997a) we determined behavioral thresholds for discharges of both sexes, using synthetic playbacks of field-recorded discharges. C. gariepinus detected M. macrolepidotus male discharges down to a field gradient of 103μVpeak-peak/cm and up to a distance of 1.5m at natural field conditions. In contrast, thresholds for female discharges were not reached with our setup, and we presume the bulldogs eaten by catfish are predominantly male.

Observations on cucullanid nematodes from freshwater fishes in Mexico, including Dichelyne mexicanus sp. n.

PubMed

Caspeta-Mandujano, J M; Moravec, F; Salgado-Maldonado, G

1999-01-01

A new cucullanid nematode, Dichelyne mexicanus sp. n., is described from the intestine of three species of fishes, Agonostomus monticola (Bancroft) (Mugilidae, Perciformes) (type host), Ictalurus balsanus (Jordan et Snyder) (Ictaluridae, Siluriformes) and Cichlasoma beani (Jordan) (Cichlidae, Perciformes), from three rivers (La Maquina River, Veracruz; Chontalcoatlán River, Guerrero and Santiago River, Nayarit) in central Mexico. This species is characterised by the absence of a ventral sucker in the male (subgenus Dichelyne) and it differs from its congeners mainly in possessing very unequal and dissimilar spicules (left 0.465-0.768 mm and right 293-548 mm long), an asymmetrical gubernaculum, and two intestinal caeca. Another cucullanid nematode, Cucullanus caballeroi Petter, 1977, is reported from Dormitator maculatus (Bloch) (Eleotridae, Perciformes) from the La Palma and La Maquina Rivers and Balzapote stream, Veracruz, being briefly described and illustrated; this represents a new host record. Findings of D. mexicanus and C. caballeroi represent a new record of cucullanid nematodes from fishes in Mexican fresh waters.

Convergence among cave catfishes: long-branch attraction and a Bayesian relative rates test.

PubMed

Wilcox, T P; García de León, F J; Hendrickson, D A; Hillis, D M

2004-06-01

Convergence has long been of interest to evolutionary biologists. Cave organisms appear to be ideal candidates for studying convergence in morphological, physiological, and developmental traits. Here we report apparent convergence in two cave-catfishes that were described on morphological grounds as congeners: Prietella phreatophila and Prietella lundbergi. We collected mitochondrial DNA sequence data from 10 species of catfishes, representing five of the seven genera in Ictaluridae, as well as seven species from a broad range of siluriform outgroups. Analysis of the sequence data under parsimony supports a monophyletic Prietella. However, both maximum-likelihood and Bayesian analyses support polyphyly of the genus, with P. lundbergi sister to Ictalurus and P. phreatophila sister to Ameiurus. The topological difference between parsimony and the other methods appears to result from long-branch attraction between the Prietella species. Similarly, the sequence data do not support several other relationships within Ictaluridae supported by morphology. We develop a new Bayesian method for examining variation in molecular rates of evolution across a phylogeny.

DNA barcoding Indian freshwater fishes.

PubMed

Lakra, Wazir Singh; Singh, M; Goswami, Mukunda; Gopalakrishnan, A; Lal, K K; Mohindra, V; Sarkar, U K; Punia, P P; Singh, K V; Bhatt, J P; Ayyappan, S

2016-11-01

DNA barcoding is a promising technique for species identification using a short mitochondrial DNA sequence of cytochrome c oxidase I (COI) gene. In the present study, DNA barcodes were generated from 72 species of freshwater fish covering the Orders Cypriniformes, Siluriformes, Perciformes, Synbranchiformes, and Osteoglossiformes representing 50 genera and 19 families. All the samples were collected from diverse sites except the species endemic to a particular location. Species were represented by multiple specimens in the great majority of the barcoded species. A total of 284 COI sequences were generated. After amplification and sequencing of 700 base pair fragment of COI, primers were trimmed which invariably generated a 655 base pair barcode sequence. The average Kimura two-parameter (K2P) distances within-species, genera, families, and orders were 0.40%, 9.60%, 13.10%, and 17.16%, respectively. DNA barcode discriminated congeneric species without any confusion. The study strongly validated the efficiency of COI as an ideal marker for DNA barcoding of Indian freshwater fishes.

Complete mitochondrial genome of the Freshwater Catfish Rita rita (Siluriformes, Bagridae).

PubMed

Lashari, Punhal; Laghari, Muhammad Younis; Xu, Peng; Zhao, Zixia; Jiang, Li; Narejo, Naeem Tariq; Deng, Yulin; Sun, Xiaowen; Zhang, Yan

2015-01-01

The complete mitochondrial genome of Catfish, Rita rita, was isolated by LA PCR (TakaRa LAtaq, Dalian, China); and sequenced by Sanger's method to obtain the complete mitochondrial genome, which is listed Critically Endangered and Red Listed species. The complete mitogenome was 16,449 bp in length and contains 13 typical vertebrate protein-coding genes, 2 rRNA and 22 tRNA genes. The whole genome base composition was estimated to be 33.40% A, 27.43% C, 14.26% G and 24.89% T. The complete mitochondrial genome of catfish, Rita rita provides the basis for genetic breeding and conservation studies.

Genetic Variation of the Endangered Neotropical Catfish Steindachneridion scriptum (Siluriformes: Pimelodidae)

PubMed Central

Paixão, Rômulo V.; Ribolli, Josiane; Zaniboni-Filho, Evoy

2018-01-01

Steindachneridion scriptum is an important species as a resource for fisheries and aquaculture; it is currently threatened and has a reduced occurrence in South America. The damming of rivers, overfishing, and contamination of freshwater environments are the main impacts on the maintenance of this species. We accessed the genetic diversity and structure of S. scriptum using the DNA barcode and control region (D-loop) sequences of 43 individuals from the Upper Uruguay River Basin (UUR) and 10 sequences from the Upper Paraná River Basin (UPR), which were obtained from GenBank. S. scriptum from the UUR and the UPR were assigned in two distinct molecular operational taxonomic units (MOTUs) with higher inter-specific K2P distance than the optimum threshold (OT = 0.0079). The COI Intra-MOTU distances of S. scriptum specimens from the UUR ranged from 0.0000 to 0.0100. The control region indicated a high number of haplotypes and low nucleotide diversity, compatible with a new population in recent expansion process. Genetic structure was observed, with high differentiation between UUR and UPR basins, identified by BAPS, haplotype network, AMOVA (FST = 0.78, p < 0.05) and Mantel test. S. scriptum from the UUR showed a slight differentiation (FST = 0.068, p < 0.05), but not isolation-by-distance. Negative values of Tajima’s D and Fu’s Fs suggest recent demographic oscillations. The Bayesian skyline plot analysis indicated possible population expansion from beginning 2,500 years ago and a recent reduction in the population size. Low nucleotide diversity, spatial population structure, and the reduction of effective population size should be considered for the planning of strategies aimed at the conservation and rehabilitation of this important fisheries resource. PMID:29520295

[Skin histology and morphometry of the fish Eremophilus mutisii (Trychomecteridae, Siluriformes)].

PubMed

Bonilla Lizarazo, Rocío Johanna; Quintero Virguez, Marllury; Ramírez, Edwin Gómez; Rodríguez Caicedo, Daniel; Hurtado Giraldo, Hermán

2008-06-01

The tropical freshwater fish Eremophylus mutisii is endemic to the Cundinamarca highland in Colombia. Skin samples (0.5x0.5 cm2) were taken from 11 specimens at six body parts (mandible, dorsal head, dorsal trunk, caudal trunk, medial trunk and abdominal area), fixed in 4% formaldehyde, dehydrated in 95% ethanol and 99% isopropanol, embedded in paraffin and sectioned at 5 sm. The skin is made of two mayor cutaneous layers (epidermis and dermis) and a subcutaneous layer (hypodermis). The epidermis presents three layers with secretory cells, epithelial cells and a few taste buds; the dermis is separated from the epidermis by a basal membrane. We observed fibroblasts, two layers of melanophors and some blood vessels; the hypodermis has vascularized adipose tissue. Skin thickness changes with body area; the dermis is thicker than the epidermis; skin has more club cells than mucous cells. The medial trunk area has the largest number of club and mucous cells. The skin of E. mutissi seems to mainly have a protective function.

First description of a Pliocene ichthyofauna from Central Africa (site KL2, Kolle area, Eastern Djurab, Chad): What do we learn?

NASA Astrophysics Data System (ADS)

Otero, Olga; Pinton, Aurélie; Mackaye, Hassan Taisso; Likius, Andossa; Vignaud, Patrick; Brunet, Michel

2009-06-01

This is the first extensive study of a freshwater fish fauna from a Pliocene site in Central Africa, based on fossils collected at the KL2 site in the fossiliferous area of Kolle (Lower Pliocene, Chad). A relatively high fish diversity is revealed, confirming the presence of 19 taxa: Polypteriformes, Polypteridae ( Polypterus sp.); Osteoglossiformes, Osteoglossidae ( Heterotis sp.), Mormyriformes, Gymnarchidae ( Gymnarchus sp. cf. niloticus); Cypriniformes, Cyprinidae ( Labeo sp.); Characiformes, Alestidae ( Hydrocynus; Alestinae type Alestes/ Brycinus; Sindacharax sp. cf. deserti, Sindacharax sp.), Distichodontidae ( Distichodus sp.); Siluriformes, Ariidae (cf. Calarius), ?Bagridae (cf. Bagrus), Claroteidae (cf. Clarotes), Mochokidae ( Synodontis sp.), Clariidae ( Clarias sp. or Heterobranchus sp.); Perciformes family indet. ( Semlikiichthys sp. cf. darsao), Latidae ( Lates sp. cf. niloticus), Cichlidae indet., and Perciformes indet.; Tetraodontiformes Tetraodontidae ( Tetraodon sp.). The aquatic environment corresponding to the fossil fish assemblage might be a floodplain crossed by well-oxygenated open waters. Compared with a contemporaneous East African region, the mid-Pliocene Chadian fish diversity reveals a certain endemicity, while connections between the Niger and the Chadian basin are suspected because of the presence of a freshwater ariid fish in Kolle.

The fish fauna in tropical rivers: the case of the Sorocaba River basin, São Paulo, Brazil.

PubMed

Smith, Welber Senteio; Petrere Júnior, Miguel; Barrella, Walter

2003-01-01

A survey was carried out on the fish species in the Sorocaba River basin, the main tributary of the left margin of the Tietê River, located in the State of São Paulo, Brazil. The species were collected with gill nets. After identification of the specimens, their relative abundance, weight and standard length were determined. Up to the present moment there are not any studies that focus this subject in this hydrographic basin. Fifty-three species, distributed in eighteen families and six orders were collected. Characiformes were represented by twenty-eight species, Siluriformes by seventeen species, the Gymnotiformes by three species, Perciformes and Cyprinodontiformes by two species, and the Synbranchiformes by one species. Among the collected species there were two exotic. The most abundant species were Astyanax fasciatus and Hypostomus ancistroides. In relation to total weight the most representative species were Hoplias malabaricus and Hypostomus ancistroides. Cyprinus carpio, Prochilodus lineatus, Schizodon nasutus and Hoplias malabaricus were the most representative species in relation to average weight. Largest standard length were recorded for Sternopygus macrurus, Steindachnerina insculpta, Eigenmannia aff. virescens and Cyprinus carpio.

Occurrence of two novel actinospore types (Cnidaria: Myxozoa) in fish farms in Mato Grosso do Sul state, Brazil.

PubMed

Milanin, Tiago; Atkinson, Stephen D; Silva, Márcia R M; Alves, Roberto G; Tavares, Luiz Eduardo R; Ribeiro, Amanda M; Maia, Antonio A M

2018-06-01

We investigated the involvement of oligochaetes in the life cycles of fresh water myxozoan parasites in Brazil. In a fish farm in the State of Mato Grosso do Sul, we examined 192 oligochaetes and found that two (1%) released Aurantiactinomyxon type actinospores. We identified infected oligochaetes by morphology: both were Pristina synclites, from family Naididae. This is the first report of the involvement of this species in the life cycle of myxozoans. Small-subunit ribosomal DNA sequences of Aurantiactinomyxon type 1 (1882 nt) and Aurantiactinomyxon type 2 (1900 nt) did not match any previously sequenced myxozoan in the NCBI database, with the highest BLAST search similarities of 83% with Myxobolus batalhensis MF361090 and 93% with Henneguya maculosus KF296344, respectively, and the two aurantiactinomyxons were only 75% similar to each other (over ~ 1900 bases). Phylogenetic analyses showed that Aurantiactinomyxon type 1 had closest affinities with myxozoans from fish hosts in Order Characiformes, and Aurantiactinomyxon type 2 had affinities with myxozoans from fish of Order Siluriformes.

Revision of Tympanopleura Eigenmann (Siluriformes: Auchenipteridae) with description of two new species

USGS Publications Warehouse

Walsh, Stephen J.; Ribeiro, Frank R.V.; Rapp Py-Daniel, Lúcia H.

2015-01-01

The Neotropical catfish genus Tympanopleura, previously synonymized within Ageneiosus, is revalidated and included species are reviewed. Six species are recognized, two of which are described as new. Tympanopleura is distinguished from Ageneiosus by having an enlarged gas bladder not strongly encapsulated in bone; a prominent pseudotympanum consisting of an area on the side of the body devoid of epaxial musculature where the gas bladder contacts the internal coelomic wall; short, blunt head without greatly elongated jaws; and smaller adult body size. Species of Tympanopleura are distinguished from each other on the basis of unique meristic, morphometric, and pigmentation differences. Ageneiosus melanopogon and Tympanopleura nigricollis are junior synonyms ofTympanopleura atronasus. Tympanopleura alta is a junior synonym of Tympanopleura brevis. A lectotype is designated for T. brevis. Ageneiosus madeirensis is a junior synonym of Tympanopleura rondoni. Tympanopleura atronasus, T. brevis, T. longipinna, and T. rondoni are relatively widespread in the middle and upper Amazon River basin. Tympanopleura cryptica is described from relatively few specimens collected in the upper portion of the Amazon River basin in Peru and the middle portion of that basin in Brazil. Tympanopleura piperata is distributed in the upper and middle Amazon River basin, as well as in the Essequibo River drainage of Guyana.

The complete mitochondrial genome of the armored catfish, Hypostomus plecostomus (Siluriformes: Loricariidae).

PubMed

Liu, Shikai; Zhang, Jiaren; Yao, Jun; Liu, Zhanjiang

2016-05-01

The complete mitochondrial genome of the armored catfish, Hypostomus plecostomus, was determined by next generation sequencing of genomic DNA without prior sample processing or primer design. Bioinformatics analysis resulted in the entire mitochondrial genome sequence with length of 16,523 bp. The H. plecostomus mitochondrial genome is consisted of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 1 control region, showing typical circular molecule structure of mitochondrial genome as in other vertebrates. The whole genome base composition was estimated to be 31.8% A, 27.0% T, 14.6% G, and 26.6% C, with A/T bias of 58.8%. This work provided the H. plecostomus mitochondrial genome sequence which should be valuable for species identification, phylogenetic analysis and conservation genetics studies in catfishes.

Cytogenetics of two sympatric Corydoras species (pisces, siluriformes, challichtyidae) of Southern Brazil.

PubMed

Artoni, R F; Terêncio, M L; Vicari, M R; Matiello, M C A; Cestari, M M; Bertollo, L A C

2006-02-01

Karyotypic data are presented for two sympatric Corydoras species of the Lagoa Dourada, namely, C. ehrhadti and C. paleatus, which are found in the upper Tibagi river basin (Ponta Grossa, State of Paraná, Brazil). The same diploid number and karyotypic formula were observed in both species/populations. A great similarity in the constitutive heterochromatin distribution and in the activity of nucleolar organizer regions was also found. The use of in situ hybridization with a fluorescent 18S rDNA probe allowed for the identification of the species/populations through the location of ribosomal sites.

The ichthyofauna of limnic systems in Quaternary deposits of extreme southern Brazil

PubMed Central

Assumpção, Cindy M.; Quintela, Fernando M.; Corrêa, Fabiano; Loebmann, Daniel

2016-01-01

Abstract The Quaternary in the state of Rio Grande do Sul (RS), southern Brazil, is geologically represented by the coastal plain and was originated by successive events of Pleistocene-Holocene marine transgressions and the occurrence of alluvial deposits. This paper aimed to characterize the fish assemblage occurring in a swampy Quaternary area adjacent to Lagoa Pequena, a lacustrine system connected to the west margin of the Laguna dos Patos estuary. A checklist is also provided of the ichthyofauna so far recorded in limnic systems of Quaternary deposits in the state of Rio Grande do Sul. A total of 42 species was recorded, distributed in nine orders, 18 families and 31 genera. Characidae and Cichlidae were the most representative families, comprising 15 and 4 species respectively. A bibliographic revision associated to our sample data revealed the occurrence of 156 species in limnic systems inserted in RS Quaternary deposits (114 limnic, 15 marine/estuarine/limnic, ten marine/estuarine, nine estuarine/limnic and eight marine). Characiformes and Siluriformes are the most diverse orders, corroborating the Neotropical pattern. Seven species can be considered endemic to RS Quaternary deposits. PMID:28174498

[Species composition and geographical distribution of threatened fishes in Yunnan Province of Southwest China].

PubMed

Zhang, Qian; Zhong, Jin-Xin

2013-05-01

Based on the related published papers, and by using Geographic Information System (ArcGIS 9.3), this paper analyzed the species composition and geographical distribution of threatened fishes in Yunnan Province of Southwest China. There were 83 threatened species living in the Province, belonging to 5 orders, 13 families, and 47 genera. Cypriniformes was absolutely dominant, with 64 species, followed by Siluriformes, with 16 species. Cyprinidae fishes had 51 species, accounting for 79.7% of Cypriniformes. The most species of Cyprinid fishes were of Barbinae (14 species), Cyprininae (10 species), and Cultrinae (10 species). The threatened fishes could be divided into two zoogeographical regions, i. e., Tibetan Plateau region and Oriental region, and their species composition and geographical distribution were resulted from the historical evolution adapted to the related environments. Whatever in rivers and in lakes, the Cyprinid fishes were both absolutely dominant, occupying 36.1% and 31.3% of the total, respectively. The Cyprinid fishes in rivers were mostly of endangered species, while those in lakes were mostly of vulnerable species. The factors affecting the threatened fishes in the Province were discussed from the two aspects of geodynamic evolution and present situation.

Description of a new genus and three new species of Otothyrinae (Siluriformes, Loricariidae)

PubMed Central

Roxo, Fábio F.; Silva, Gabriel S. C.; Ochoa, Luz E.; Oliveira, Claudio

2015-01-01

Abstract The genus Hisonotus was resurrected as a member of the tribe Otothyrini (actually subfamily Otothyrinae). However, phylogenetic studies based on morphological and molecular data showed that Hisonotus is not monophyletic and independent lineages can be identified, such as the group composed of the species Hisonotus insperatus, Hisonotus luteofrenatus, Hisonotus oliveirai, Hisonotus paresi and Hisonotus piracanjuba, a lineage unrelated to that containing the type species of the genus Hisonotus (Hisonotus notatus). Herein, based in molecular and morphological data, a new genus is described to accommodate the lineage mentioned above, into which are also added three new species. This new genus can be distinguished from other genera of Otothyrinae by the following combination of characters: (1) a pair of rostral plates at the tip of the snout; (2) two large pre-nasal plates just posterior to the rostral plates; (3) a supra-opercular plate that receives the laterosensory canal from the compound pterotic before the preopercle; (4) a well developed membrane at anal opening in females; and (5) a V-shaped spinelet. A key to species of Curculionichthys is provided. PMID:26668550

Revision of Notoglanidium and related genera (Siluriformes: Claroteidae) based on morphology and osteology.

PubMed

Geerinckx, Tom; Vreven, Emmanuel; Dierick, Manuel; Van Hoorebeke, Luc; Adriaens, Dominique

2013-01-01

Apart from the well-demarcated genera Auchenoglanis and Parauchenoglanis, Auchenoglanidinae, one of the two sub-families of the African catfish family Claroteidae, suffers from poor resolution at the generic level. For the remaining genera, Notoglanidium, Liauchenoglanis, Platyglanis and Anaspidoglanis, generic discriminations are rudimentary. In addition, several included species are poorly defined and barely represented in scientific collections. Until now, no study has included morphological data for all currently known species, and for many species osteological data were non-existent. Molecular data for most species are lacking as well. Here, a comprehensive account of the morphology and osteology is given of all species included in these four genera. Using computed tomography (CT scanning) as well as clearing and staining, osteological characters were combined with biometric, meristic and other morphological data to revise the status of these genera and included species. Morphological and osteological data, submitted to a phylogenetic analysis, agree with metric and meristic data that all Liauchenoglanis, Platyglanis and Anaspidoglanis cannot be discerned from Notoglanidium; their genus and type species descriptions fail to be distinguished from Notoglanidium. Here their synonymy is proposed, resulting in a single valid genus, including nine species of which the validity is confirmed. A key to the genus and included species, as well as a diagnosis and description for each of them, are provided.

Tapeworms (Cestoda: Caryophyllidea), parasites of Clarias batrachus (Pisces: Siluriformes) in the Indomalayan region.

PubMed

Ash, Anirban; Scholz, Tomáš; Oros, Mikuláš; Kar, Pradip Kumar

2011-06-01

Revision of monozoic cestodes (Caryophyllidea) parasitic in commercially important walking catfish Clarias batrachus (L.) in tropical Asia (Indomalayan zoogeographical region) was carried out, based on the evaluation of newly collected material from India, Indonesia, and Thailand, as well as a study of type specimens. Instead of the 59 nominal taxa of 15 genera from 3 caryophyllidean families previously described, only 8 species of the Lytocestidae are considered to be valid: Bovienia indica (Niyogi, Gupta and Agarwal, 1982) n. comb.; Bovienia raipurensis (Satpute and Agarwal, 1980) Mackiewicz, 1994; Bovienia serialis (Bovien, 1926) Fuhrmann, 1931; Djombangia penetrans Bovien, 1926; Lucknowia microcephala (Bovien, 1926) n. comb.; Lytocestus indicus (Moghe, 1925) Woodland 1926; Pseudocaryophyllaeus ritai Gupta and Singh, 1983; and Pseudocaryophyllaeus tenuicollis (Bovien, 1926) n. comb. All valid species are redescribed and SEM photomicrographs of their scolices and photomicrographs of their eggs are provided for the first time. Crescentovitus Murhar, 1963, Heeradevina Srivastav and Khare, 2005, Pseudobatrachus Pathak and Srivastav, 2005, Pseudobilobulata Srivastav and Lohia, 2002, Pseudoclariasis Pathak, 2002, and Pseudoinverta Pathak, 2002 are invalidated and 50 nominal species are newly synonymized, including 4 species described from other fish hosts. Taxonomic status of the remaining caryophyllidean taxa reported from C. batrachus (at least 6 taxa) could not be clarified because of the unavailability of their original descriptions. A key to identification of caryophyllidean tapeworms parasitic in C. batrachus is provided. To avoid current inflation of descriptions of invalid taxa, researchers are strongly encouraged to work only with well-fixed material; damaged, decomposed, or strongly flattened specimens should not be used for taxonomic studies, and type specimens must always be deposited in internationally recognized collections.

On the type locality of Sorubim trigonocephalus Miranda-Ribeiro, 1920 (Siluriformes: Pimelodidae).

PubMed

Ohara, Willian Massaharu; Neuhaus, Emanuel Bruno

2016-07-11

Sorubim trigonocephalus was described in 1920 by Alípio de Miranda Ribeiro, based on a single specimen collected in a locality identified as "Porto Velho", during the "Comissão das Linhas Telegráficas Estratégicas de Mato Grosso ao Amazonas" (more commonly known as Rondon Commission). Given that the type locality is Porto Velho, the species has been referred to the Madeira River basin (Lundberg & Littmann, 2003; Littmann, 2007; Eschmeyer et al., 2016). Nevertheless, after its description, no additional specimens were collected in the Madeira basin despite several ichthyological expeditions undertaken to the area (Santos, 1996; Camargo & Giarrizzo, 2007; Rapp Py-Daniel et al., 2007; Perin et al., 2007; Pedroza et al., 2012; Casatti et al., 2013; Queiroz et al., 2013a), some of them including region of Porto Velho (Fowler, 1913; Araújo et al., 2009; Torrente-Vilara et al., 2011; Queiroz et al., 2013b).

Aspidoras mephisto, new species: The first troglobitic Callichthyidae (Teleostei: Siluriformes) from South America

PubMed Central

Bichuette, Maria Elina

2017-01-01

Aspidoras mephisto n. sp. is described from the Anésio-Russão cave system, upper Tocantins River basin, Goiás, Brazil. The species can be readily distinguished from its congeners by troglomorphic features and also by presenting the following combination of features: infraorbital 1 generally with well-developed ventral laminar; or moderately developed; poorly-developed serrations on posterior margin of pectoral spine; nuchal plate not externally visible; dorsal fin, even in conspicuously colored specimens, with only dark brown or black chromatophores concentrated on rays, forming spots in some specimens; membranes hyaline; or sparse dark brown or black chromatophores on membranes, not forming any conspicuous pattern; and inner laminar expansion of infraorbital 1 moderately developed. Information about its habitat, ecology, behaviour and conservation status are provided and also a brief description of the juvenile stage. PMID:28248959

Geographical genetics of Pseudoplatystoma punctifer (Castelnau, 1855) (Siluriformes, Pimelodidae) in the Amazon Basin.

PubMed

Telles, M P C; Collevatti, R G; Braga, R S; Guedes, L B S; Castro, T G; Costa, M C; Silva-Júnior, N J; Barthem, R B; Diniz-Filho, J A F

2014-05-09

Geographical genetics allows the evaluation of evolutionary processes underlying genetic variation within and among local populations and forms the basis for establishing more effective strategies for biodiversity conservation at the population level. In this study, we used explicit spatial analyses to investigate molecular genetic variation (estimated using 7 microsatellite markers) of Pseudoplatystoma punctifer, by using samples obtained from 15 localities along the Madeira River and Solimões, Amazon Basin. A high genetic diversity was observed associated with a relatively low FST (0.057; P < 0.001), but pairwise FST values ranged from zero up to 0.21 when some pairs of populations were compared. These FST values have a relatively low correlation with geographic distances (r = 0.343; P = 0.074 by Mantel test), but a Mantel correlogram revealed that close populations (up to 80 km) tended to be more similar than expected by chance (r = 0.360; P = 0.015). The correlogram also showed a exponential-like decrease of genetic similarity with distance, with a patch-size of around 200 km, compatible with isolation-by-distance and analogous processes related to local constraints of dispersal and spatially structured levels of gene flow. The pattern revealed herein has important implications for establishing strategies to maintain genetic diversity in the species, especially considering the threats due to human impacts caused by building large dams in this river system.

The genera Isorineloricaria and Aphanotorulus (Siluriformes: Loricariidae)
with description of a new species.

PubMed

Ray, C Keith; Armbruster, Jonathan W

2016-02-04

We review the complex history of those species included in the Hypostomus emarginatus species complex and recognize them in Isorineloricaria and Aphanotorulus. Isorineloricaria consists of four valid species: I. acuarius n. sp., I. spinosissima, I. tenuicauda, and I. villarsi. Aphanotorulus consists of six valid species: A. ammophilus, A, emarginatus, A. gomesi, A. horridus, A. phrixosoma, and A. unicolor. Plecostomus annae and Hypostoma squalinum are placed in the synonymy of A. emarginatus; Plecostomus biseriatus, P. scopularius, and P. virescens are placed in the synonymy of A. horridus; Plecostomus winzi is placed in the synonymy of I. tenuicauda, and one new species, I. acuarius is described from the Apure River basin of Venezuela. Aphanotoroulus can be distinguished from Isorineloricaria by having caudal peduncles that do not become greatly lengthed with size and that are oval in cross section (vs. caudal peduncle proportions that get proportionately longer with size and that become round in cross-section), and by having small dark spots (less than half plate diameter) on a light tan background (vs. spots almost as large as lateral plates on a nearly white background.

A New Species of Tiger Pleco Panaqolus (Siluriformes: Loricariidae) from the Xingu Basin, Brazil

PubMed Central

Melo de Sousa, Leandro

2016-01-01

Panaqolus tankei is described from the Xingu River, Brazil. The new species is diagnosed from P. albomaculatus, P. dentex, P. nix, P. nocturnus, and P. koko by its color pattern consisting of dark and light diagonal bars on the body and bands on the fins (vs. body and fins without bars or bands); from P. albivermis, P. maccus, and P. purusiensis by the width of the dark bars being more or less the same of the light bars (vs. dark bars at least two or three times wider than light bars) and from P. changae by the absence of vermiculation on the head (vs. vermiculation present on head). The new species differs from P. gnomus by the orientation of the bars from posterodorsal to anteroventral direction (vs. anterodorsal to posteroventral direction), and from P. claustellifer by the orientation of the bands in the dorsal fin that are not parallel to the margin (vs. parallel to the margin). The barcoding region (COI) was sequenced for the new species, sequences were deposited in GenBank and were compared with congeners from other drainages. With regard to the current construction of a hydroelectric power plant (a so-called mega dam) in the Xingu River, herewith we increase knowledge of the river Xingu’s ichthyofauna and, thus improve the assessment of the impacts of that construction on the river. PMID:27828981

A New Species of Tiger Pleco Panaqolus (Siluriformes: Loricariidae) from the Xingu Basin, Brazil.

PubMed

Cramer, Christian Andreas; Melo de Sousa, Leandro

2016-01-01

Panaqolus tankei is described from the Xingu River, Brazil. The new species is diagnosed from P. albomaculatus, P. dentex, P. nix, P. nocturnus, and P. koko by its color pattern consisting of dark and light diagonal bars on the body and bands on the fins (vs. body and fins without bars or bands); from P. albivermis, P. maccus, and P. purusiensis by the width of the dark bars being more or less the same of the light bars (vs. dark bars at least two or three times wider than light bars) and from P. changae by the absence of vermiculation on the head (vs. vermiculation present on head). The new species differs from P. gnomus by the orientation of the bars from posterodorsal to anteroventral direction (vs. anterodorsal to posteroventral direction), and from P. claustellifer by the orientation of the bands in the dorsal fin that are not parallel to the margin (vs. parallel to the margin). The barcoding region (COI) was sequenced for the new species, sequences were deposited in GenBank and were compared with congeners from other drainages. With regard to the current construction of a hydroelectric power plant (a so-called mega dam) in the Xingu River, herewith we increase knowledge of the river Xingu's ichthyofauna and, thus improve the assessment of the impacts of that construction on the river.

Phenoscape: Identifying Candidate Genes for Evolutionary Phenotypes

PubMed Central

Edmunds, Richard C.; Su, Baofeng; Balhoff, James P.; Eames, B. Frank; Dahdul, Wasila M.; Lapp, Hilmar; Lundberg, John G.; Vision, Todd J.; Dunham, Rex A.; Mabee, Paula M.; Westerfield, Monte

2016-01-01

Phenotypes resulting from mutations in genetic model organisms can help reveal candidate genes for evolutionarily important phenotypic changes in related taxa. Although testing candidate gene hypotheses experimentally in nonmodel organisms is typically difficult, ontology-driven information systems can help generate testable hypotheses about developmental processes in experimentally tractable organisms. Here, we tested candidate gene hypotheses suggested by expert use of the Phenoscape Knowledgebase, specifically looking for genes that are candidates responsible for evolutionarily interesting phenotypes in the ostariophysan fishes that bear resemblance to mutant phenotypes in zebrafish. For this, we searched ZFIN for genetic perturbations that result in either loss of basihyal element or loss of scales phenotypes, because these are the ancestral phenotypes observed in catfishes (Siluriformes). We tested the identified candidate genes by examining their endogenous expression patterns in the channel catfish, Ictalurus punctatus. The experimental results were consistent with the hypotheses that these features evolved through disruption in developmental pathways at, or upstream of, brpf1 and eda/edar for the ancestral losses of basihyal element and scales, respectively. These results demonstrate that ontological annotations of the phenotypic effects of genetic alterations in model organisms, when aggregated within a knowledgebase, can be used effectively to generate testable, and useful, hypotheses about evolutionary changes in morphology. PMID:26500251

Evolution of Venomous Cartilaginous and Ray-Finned Fishes.

PubMed

Smith, W Leo; Stern, Jennifer H; Girard, Matthew G; Davis, Matthew P

2016-11-01

Venom and its associated delivery systems have evolved in numerous animal groups ranging from jellyfishes to spiders, lizards, shrews, and the male platypus. Building off new data and previously published anatomical and molecular studies, we explore the evolution of and variation within venomous fishes. We show the results of the first multi-locus, ordinal-level phylogenetic analysis of cartilaginous (Chondrichthyes) and ray-finned (Actinopterygii) fishes that hypothesizes 18 independent evolutions of this specialization. Ancestral-states reconstruction indicates that among the 2386-2962 extant venomous fishes, envenomed structures have evolved four times in cartilaginous fishes, once in eels (Anguilliformes), once in catfishes (Siluriformes), and 12 times in spiny-rayed fishes (Acanthomorpha). From our anatomical studies and phylogenetic reconstruction, we show that dorsal spines are the most common envenomed structures (∼95% of venomous fish species and 15 independent evolutions). In addition to envenomed spines, fishes have also evolved venomous fangs (2% of venomous fish species, two independent evolutions), cleithral spines (2% of venomous fish species, one independent evolution), and opercular or subopercular spines (1% of venomous fish species, three independent evolutions). © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Spawning and nursery habitats of neotropical fish species in the tributaries of a regulated river

USGS Publications Warehouse

Makrakis, Maristela Cavicchioli; da Silva, Patrícia S.; Makrakis, Sergio; de Lima, Ariane F.; de Assumpção, Lucileine; de Paula, Salete; Miranda, Leandro E.; Dias, João Henrique Pinheiro

2012-01-01

This chapter provides information on ontogenetic patterns of neotropical fish species distribution in tributaries (Verde, Pardo, Anhanduí, and Aguapeí rivers) of the Porto Primavera Reservoir, in the heavily dammed Paraná River, Brazil, identifying key spawning and nursery habitats. Samplings were conducted monthly in the main channel of rivers and in marginal lagoons from October through March during three consecutive spawning seasons in 2007-2010. Most species spawn in December especially in Verde River. Main river channels are spawning habitats and marginal lagoons are nursery areas for most fish, mainly for migratory species. The tributaries have high diversity of larvae species: a total of 56 taxa representing 21 families, dominated by Characidae. Sedentary species without parental care are more abundant (45.7%), and many long-distance migratory fish species are present (17.4%). Migrators included Prochilodus lineatus, Rhaphiodon vulpinus, Hemisorubim platyrhynchos, Pimelodus maculatus, Pseudoplatystoma corruscans, Sorubim lima, two threatened migratory species: Salminus brasiliensis and Zungaro jahu, and one endangered migratory species: Brycon orbignyanus. Most of these migratory species are vital to commercial and recreational fishing, and their stocks have decreased drastically in the last decades, attributed to habitat alteration, especially impoundments. The fish ladder at Porto Primavera Dam appears to be playing an important role in re-establishing longitudinal connectivity among critical habitats, allowing ascent to migratory fish species, and thus access to upstream reaches and tributaries. Establishment of Permanent Conservation Units in tributaries can help preserve habitats identified as essential spawning and nursery areas, and can be key to the maintenance and conservation of the fish species in the Paraná River basin.

Cetopsis varii, a new species of whale catfish (Siluriformes: Cetopsidae) from the Meta Basin, Colombia.

PubMed

Abrahão, V P; de Pinna, M C C

2018-06-01

Cetopsis varii sp. nov. Cetopsidae (Cetopsinae) is described from the Río Meta basin in eastern Colombia, at middle portions of the Río Orinoco basin. The new species differs from some congeners by a combination of some features: the absence of a humeral spot, presence of eye, conical teeth on vomer and dentary and rounded posterior nares. Various details of body, dorsal and caudal-fin pigmentation along with morphological features distinguish the new species from remaining congeners. The osteology of the new species is investigated through high-resolution X-ray computed tomography. Data thus obtained are used to code the new species for character states utilized in a previous phylogenetic analysis of Cetopsidae. Analysis of the expanded matrix shows that C. varii is the sister group to C. orinoco. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Karyotype Diversity and Evolutionary Trends in Armored Catfish Species of the Genus Harttia (Siluriformes: Loricariidae).

PubMed

Blanco, Daniel Rodrigues; Vicari, Marcelo Ricardo; Lui, Roberto Laridondo; Traldi, Josiane Baccarin; Bueno, Vanessa; Martinez, Juliana de Fátima; Brandão, Heleno; Oyakawa, Osvaldo Takeshi; Moreira Filho, Orlando

2017-04-01

Most species of the genus Harttia inhabits the headwaters of small tributaries, but some species are restricted to the main channel of some rivers. This feature, combined with limited dispersal ability, leads to the formation of small isolated populations with reduced gene flow. Currently, there are 23 taxonomically defined and recognized species, and 17 of these are found in Brazil, distributed in several hydrographic basins. Despite this diversity, few chromosomal data for the species belonging to this genus are found in the literature. Thus, this study analyzed, by classical and molecular cytogenetics methodologies, the chromosomal diversity of this genus, to discuss the processes that are involved in the evolution and karyotype differentiation of the species of the group. Seven species of Harttia were analyzed: H. kronei, H. longipinna, H. gracilis, H. punctata, H. loricariformis, H. torrenticola, and H. carvalhoi. The chromosomal diversity found in these species includes different diploid and fundamental numbers, distinct distribution of several repetitive sequences, the presence of supernumerary chromosomes in H. longipinna and multiple sex chromosome systems of the type XX/XY 1 Y 2 in H. carvalhoi and X 1 X 1 X 2 X 2 /X 1 X 2 Y in H. punctata. Lastly, our data highlight the genus Harttia as an excellent model for evolutionary studies.

Morphology and Small-Subunit Ribosomal DNA Sequence of Henneguya Adiposa (Myxosporea) From Ictalurus punctatus (Siluriformes)

USDA-ARS?s Scientific Manuscript database

The original description of Henneguya adiposa, a myxozoan parasitizing channel catfish Ictalurus punctatus, is supplemented with new data on spore morphology, including photomicrographs and line drawings, as well as 18S small-subunit (SSU) ribosomal DNA (rDNA) sequence. Elongate, translucent, linear...

Molecular systematic and historical biogeography of the armored Neotropical catfishes Hypoptopomatinae and Neoplecostominae (Siluriformes: Loricariidae).

PubMed

Chiachio, Márcio Cesar; Oliveira, Claudio; Montoya-Burgos, Juan I

2008-11-01

The Neotropics possess the greatest freshwater fish diversity of the world, rendering the study of their evolutionary history extremely challenging. Loricariidae catfishes are one of the most diverse components of the Neotropical ichthyofauna and despite a long history of classification, major issues still need elucidation. Based on a nuclear gene, we present a robust phylogeny of two former loricariid subfamilies: Hypoptopomatinae and Neoplecostominae. Our results show that Neoplecostominae is nested within Hypoptopomatinae, and is the sister group to the former Otothyrini tribe. According to our results, supplemented by morphological observations, we erect two new subfamilies, the Otothyrinae and a new Hypoptopomatinae, and modify the Neoplecostominae by including the genus Pseudotocinclus. The uncovered evolutionary relationships allow a detailed analysis of their historical biogeography. We tested two Dispersal-Extinction-Cladogenesis models for inferring the distribution range evolution of the new subfamilies, and show that the model having no constrains performs better than a model constraining long-range dispersal. The Maximum Likelihood reconstructions of ancestral ranges showed a marked division between the Amazonian origin of the Hypoptopomatinae and the eastern coastal Brazil+Upper Paraná origin of the Neoplecostominae and Otothyrinae. Markedly few instances of dispersal across the border separating the Amazon basin and the Paraná-Paraguay+eastern coastal Brazil+Uruguay were reconstructed. This result is in clear contrast with the historical biogeography of many Neotropical fishes, including other Loricariidae. Part of the dispersal limitation may be explained by divergent ecological specialization: lowland rivers versus mountain streams habitats. Moreover, because most species of the new subfamilies are small, we hypothesize that body size-related effects might limit their dispersal, like predation and energetic cost to migration. Finally, morphological and anatomical features are presented that limit or, to the contrary, enhance dispersal capability in these small and fascinating catfishes.

Molecular phylogeny of Banjo catfishes (Ostaryophisi: Siluriformes: Aspredinidae): A continental radiation in South American freshwaters.

PubMed

Carvalho, Tiago P; Arce H, Mariangeles; Reis, Roberto E; Sabaj, Mark H

2018-04-30

The family Aspredinidae is a moderately diverse and broadly distributed group of freshwater fishes endemic to South America. Commonly known as Banjo Catfishes, Aspredinidae currently includes 44 valid species divided among 13 genera. The first species-comprehensive hypothesis on phylogenetic relationships among aspredinids is presented. The phylogeny is based on DNA sequence data for five gene fragments (mitochondrial 16S and COI; nuclear RAG1, MYH6 and SH3PX3) from 114 individuals representing 31 species in 12 aspredinid genera. Analyses of molecular data support the monophyly of most genera (Bunocephalus excepted) and several higher-level relationships previously proposed by morphological studies. Based on the molecular phylogeny, a new suprageneric classification for Aspredinidae is proposed with the new monotypic subfamily Pseudobunocephalinae as the sister taxon to all other aspredinids. Copyright © 2018 Elsevier Inc. All rights reserved.

A new species of Amaralia Fowler (Siluriformes: Aspredinidae) from the Paraná-Paraguay River Basin.

PubMed

Friel, John P; Carvalho, Tiago P

2016-03-11

A new species of the banjo catfish genus Amaralia is described from the Paraná-Paraguay River Basin in central-western Brazil, Paraguay and northern Argentina. Amaralia oviraptor is distinguished from its single and allopatric congener, Amaralia hypsiura, by the greater number of dorsal-fin rays (3 vs. 2); by the absence of lateral contact between middle and posterior nuchal plates (vs. middle and posterior nuchal plates contacting each other laterally); and by a longer cleithral process (17.4-19.5 % of SL, mean 18.2 % vs. 14.0-17.2 % of SL, mean=15.5 %). Comments on the peculiar oophagic diet of Amaralia and an extended diagnosis of the genus are provided.

Past connection and isolation of catchments: The sea-level changes affect the distribution and genetic variability of coastal freshwater fishes

NASA Astrophysics Data System (ADS)

Tschá, Marcel K.; Bachmann, Lutz; Abilhoa, Vinícius; Boeger, Walter A.

2017-05-01

The Atlantic coast of South America is characterized by a great diversity and endemism of fishes. Past eustatic changes that promoted cycles of isolation, expansion, and connection of coastal catchments are considered putative drivers of genetic differentiation and phylogenetic diversity. It is hypothesized that recent eustatic movements have left signs of impact on the demographic history and local distribution patterns of freshwater fishes. This study addressed the phylogeography and demographic history of two siluriform (Scleromystax barbatus, Rineloricaria sp.) and one characiform (Mimagoniates microlepis) fish species from the coastal plain of the state of Paraná, Paranaguá Bay, Brazil. Nucleotide sequence data of the mitochondrial cytochrome b gene support the hypothesis that the populations of the three species are genetically differentiated at all sampled catchments. Haplotype networks of these populations indicate different histories and include scenarios of secondary contact, population expansion, and isolation. Neutrality tests and the reconstructed patterns of demographic history in mismatch distributions were also consistent with population expansion in the western basins and, in general, secondary contact in the northern basins. Our results are consistent with the reconstructed paleodrainage in the region and with the hypothesis that recurrent reconnections and isolation of streams associated with eustatic changes have strongly influenced the current pattern of diversity, and reflect the distribution of freshwater fishes in this coastal hydrographic system.

A Fish Assemblage from the Middle Eocene from Libya (Dur At-Talah) and the Earliest Record of Modern African Fish Genera

PubMed Central

Otero, Olga; Pinton, Aurélie; Cappetta, Henri; Adnet, Sylvain; Valentin, Xavier; Salem, Mustapha; Jaeger, Jean-Jacques

2015-01-01

In the early nineteen sixties, Arambourg and Magnier found some freshwater fish (i.e., Polypterus sp., Siluriformes indet. and Lates sp.) mixed with marine members in an Eocene vertebrate assemblage at Gebel Coquin, in the southern Libyan Desert. This locality, aged ca 37–39Ma and now known under the name of Dur At-Talah, has been recently excavated. A new fish assemblage, mostly composed of teeth, was collected by the Mission Paléontologique Franco-Libyenne. In this paper, we describe freshwater fish members including a dipnoan (Protopterus sp.), and several actinopterygians: bichir (Polypterus sp.), aba fish (Gymnarchus sp.), several catfishes (Chrysichthys sp. and a mochokid indet.), several characiforms (including the tiger fish Hydrocynus sp., and one or two alestin-like fish), and perciforms (including the snake-head fish Parachanna sp. and at least one cichlid). Together with the fossiliferous outcrops at Birket Qarun in Egypt, the Libyan site at Dur At-Talah reduces a 10-Ma chronological gap in the fossil record of African freshwater fish. Their fish assemblages overlap in their composition and thus constitute a rather homogenous, original and significant amount of new elements regarding the Paleogene African ichthyofauna. This supports the establishment of the modern African freshwater fish fauna during this time period because these sites mostly contain the earliest members known in modern genera. PMID:26674637

A Fish Assemblage from the Middle Eocene from Libya (Dur At-Talah) and the Earliest Record of Modern African Fish Genera.

PubMed

Otero, Olga; Pinton, Aurélie; Cappetta, Henri; Adnet, Sylvain; Valentin, Xavier; Salem, Mustapha; Jaeger, Jean-Jacques

2015-01-01

In the early nineteen sixties, Arambourg and Magnier found some freshwater fish (i.e., Polypterus sp., Siluriformes indet. and Lates sp.) mixed with marine members in an Eocene vertebrate assemblage at Gebel Coquin, in the southern Libyan Desert. This locality, aged ca 37-39Ma and now known under the name of Dur At-Talah, has been recently excavated. A new fish assemblage, mostly composed of teeth, was collected by the Mission Paléontologique Franco-Libyenne. In this paper, we describe freshwater fish members including a dipnoan (Protopterus sp.), and several actinopterygians: bichir (Polypterus sp.), aba fish (Gymnarchus sp.), several catfishes (Chrysichthys sp. and a mochokid indet.), several characiforms (including the tiger fish Hydrocynus sp., and one or two alestin-like fish), and perciforms (including the snake-head fish Parachanna sp. and at least one cichlid). Together with the fossiliferous outcrops at Birket Qarun in Egypt, the Libyan site at Dur At-Talah reduces a 10-Ma chronological gap in the fossil record of African freshwater fish. Their fish assemblages overlap in their composition and thus constitute a rather homogenous, original and significant amount of new elements regarding the Paleogene African ichthyofauna. This supports the establishment of the modern African freshwater fish fauna during this time period because these sites mostly contain the earliest members known in modern genera.

Morphology and small subunit rDNA-based phylogeny of a new Henneguya species, infecting the ornamental fish Corydoras leucomelas from the Peruvian Amazon.

PubMed

Mathews, Patrick D; Naldoni, Juliana; Adriano, Edson A

2017-12-01

A new species of Myxosporea, Henneguya loreotoensis n. sp. is described parasitizing the gill filaments from 17 of 35 specimens (48.5%) of Corydoras leucomelas (Siluriformes: Callichthyidae) caught in the Nanay River, near village Ninarumi, in the Loreto state, Peru. Mature spores were ellipsoidal in shape from the frontal view, measuring 36.2±0.1μm (36.1-36.3) in total length, 14.3±0.1μm (14.2-14.4) in body length, 5.1±0.1μm (4.9-5.3) in width and 21.9±0.1μm (21.8-22.0) in the caudal process. The two polar capsules were symmetrical and elongated, measuring 5.1±0.1μm (4.9-5.3) in length and 2.4±0.2μm (2.1-2.7) in width, containing a polar filament with five coils arranged obliquely to the longitudinal axis. The sporoplasm was binucleate. Partial sequencing of the ssu-rDNA of H. loretoensis n. sp. resulted in a total of 1676 nucleotides, and this sequence did not match any of the myxozoan available in the GenBank. The phylogenetic analysis shows H. loretoensis n. sp. as a sister species of Henneguya paraensis, another amazonian myxozoan parasite of Cichla temensis (Perciformes: Cichlidae). Copyright © 2017 Elsevier B.V. All rights reserved.

Morphology of the Epidermis of the Neotropical Catfish Pimelodella lateristriga (Lichtenstein, 1823) with Emphasis in Club Cells

PubMed Central

Damasceno, Eduardo Medeiros; Monteiro, Juliana Castro; Duboc, Luiz Fernando; Dolder, Heidi; Mancini, Karina

2012-01-01

The epidermis of Ostariophysi fish is composed of 4 main cell types: epidermal cells (or filament containing cells), mucous cells, granular cells and club cells. The morphological analysis of the epidermis of the catfish Pimelodella lateristriga revealed the presence of only two types of cells: epidermal and club cells. The latter were evident in the middle layer of the epidermis, being the largest cells within the epithelium. Few organelles were located in the perinuclear region, while the rest of the cytoplasm was filled with a non-vesicular fibrillar substance. Club cells contained two irregular nuclei with evident nucleoli and high compacted peripheral chromatin. Histochemical analysis detected prevalence of protein within the cytoplasm other than carbohydrates, which were absent. These characteristics are similar to those described to most Ostariophysi studied so far. On the other hand, the epidermal cells differ from what is found in the literature. The present study described three distinct types, as follows: superficial, abundant and dense cells. Differences among them were restricted to their cytoplasm and nucleus morphology. Mucous cells were found in all Ostariophysi studied so far, although they were absent in P. lateristriga, along with granular cells, also typical of other catfish epidermis. The preset study corroborates the observations on club cells' morphology in Siluriformes specimens, and shows important differences in epidermis composition and cell structure of P. lateristriga regarding the literature data. PMID:23226253

Seed dispersal by fishes in tropical and temperate fresh waters: The growing evidence

NASA Astrophysics Data System (ADS)

Horn, Michael H.; Correa, Sandra Bibiana; Parolin, Pia; Pollux, B. J. A.; Anderson, Jill T.; Lucas, Christine; Widmann, Peter; Tjiu, Albertus; Galetti, Mauro; Goulding, Michael

2011-11-01

Fruit-eating by fishes represents an ancient (perhaps Paleozoic) interaction increasingly regarded as important for seed dispersal (ichthyochory) in tropical and temperate ecosystems. Most of the more than 275 known frugivorous species belong to the mainly Neotropical Characiformes (pacus, piranhas) and Siluriformes (catfishes), but cypriniforms (carps, minnows) are more important in the Holarctic and Indomalayan regions. Frugivores are among the most abundant fishes in Neotropical floodplains where they eat the fruits of a wide variety of trees and shrubs. By consuming fruits, fishes gain access to rich sources of carbohydrates, lipids and proteins and act as either seed predators or seed dispersers. With their often high mobility, large size, and great longevity, fruit-eating fishes can play important roles as seed dispersers and exert strong influences on local plant-recruitment dynamics and regional biodiversity. Recent feeding experiments focused on seed traits after gut passage support the idea that fishes are major seed dispersers in floodplain and riparian forests. Overfishing, damming, deforestation and logging potentially diminish ichthyochory and require immediate attention to ameliorate their effects. Much exciting work remains in terms of fish and plant adaptations to ichthyochory, dispersal regimes involving fishes in different ecosystems, and increased use of nondestructive methods such as stomach lavage, stable isotopes, genetic analyses and radio transmitters to determine fish diets and movements.

Body size–trophic position relationships among fishes of the lower Mekong basin

PubMed Central

Montaña, Carmen G.; Winemiller, Kirk O.

2017-01-01

Body size is frequently claimed to be a major determinant of animal trophic interactions, yet few studies have explored relationships between body size and trophic interactions in rivers, especially within the tropics. We examined relationships between body size and trophic position (TP) within fish assemblages in four lowland rivers of the Lower Mekong Basin in Cambodia. Stable isotope analysis (based on δ15N) was used to estimate TP of common fish species in each river, and species were classified according to occupation of benthic versus pelagic habitats and major feeding guilds. Regression analysis yielded strong correlations between body size and TP among fishes from the Sesan and Sreprok rivers, but not those from the Mekong and Sekong rivers. The Mekong fish assemblage had higher average TP compared with those of other rivers. The relationship between body size and TP was positive and significantly correlated for piscivores and omnivores, but not for detritivores and insectivores. The body size–TP relationship did not differ between pelagic and benthic fishes. Body size significantly predicted TP within the orders Siluriformes and Perciformes, but not for Cypriniformes, the most species-rich and ecologically diverse order in the Lower Mekong River. We conclude that for species-rich, tropical fish assemblages with many detritivores and invertivores, body size would not be an appropriate surrogate for TP in food web models and other ecological applications. PMID:28280563

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

PubMed

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

2013-08-01

The biogeography of the mega-diverse, freshwater, and globally distributed Otophysi has received considerable attention. This attraction largely stems from assumptions as to their ancient origin, the clade being almost exclusively freshwater, and their suitability as to explanations of trans-oceanic distributions. Despite multiple hypotheses explaining present-day distributions, problems remain, precluding more parsimonious explanations. Underlying previous hypotheses are alternative phylogenies for Otophysi, uncertainties as to temporal diversification and assumptions integral to various explanations. We reexamine the origin and early diversification of this clade based on a comprehensive time-calibrated, molecular-based phylogenetic analysis and event-based approaches for ancestral range inference of lineages. Our results do not corroborate current phylogenetic classifications of otophysans. We demonstrate Siluriformes are never sister to Gymnotiformes and Characiformes are most likely nonmonophyletic. Divergence time estimates specify a split between Cypriniformes and Characiphysi with the fragmentation of Pangea. The early diversification of characiphysans either predated, or was contemporary with, the separation of Africa and South America, and involved a combination of within- and between-continental divergence events for these lineages. The intercontinental diversification of siluroids and characoids postdated major intercontinental tectonic fragmentations (<90 Mya). Post-tectonic drift dispersal events are hypothesized to account for their current distribution patterns. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

Body size-trophic position relationships among fishes of the lower Mekong basin.

PubMed

Ou, Chouly; Montaña, Carmen G; Winemiller, Kirk O

2017-01-01

Body size is frequently claimed to be a major determinant of animal trophic interactions, yet few studies have explored relationships between body size and trophic interactions in rivers, especially within the tropics. We examined relationships between body size and trophic position (TP) within fish assemblages in four lowland rivers of the Lower Mekong Basin in Cambodia. Stable isotope analysis (based on δ 15 N) was used to estimate TP of common fish species in each river, and species were classified according to occupation of benthic versus pelagic habitats and major feeding guilds. Regression analysis yielded strong correlations between body size and TP among fishes from the Sesan and Sreprok rivers, but not those from the Mekong and Sekong rivers. The Mekong fish assemblage had higher average TP compared with those of other rivers. The relationship between body size and TP was positive and significantly correlated for piscivores and omnivores, but not for detritivores and insectivores. The body size-TP relationship did not differ between pelagic and benthic fishes. Body size significantly predicted TP within the orders Siluriformes and Perciformes, but not for Cypriniformes, the most species-rich and ecologically diverse order in the Lower Mekong River. We conclude that for species-rich, tropical fish assemblages with many detritivores and invertivores, body size would not be an appropriate surrogate for TP in food web models and other ecological applications.

Gene structure and functional characterization of growth hormone in dogfish, Squalus acanthias.

PubMed

Moriyama, Shunsuke; Oda, Mayumi; Yamazaki, Tomohide; Yamaguchi, Kiyoko; Amiya, Noriko; Takahashi, Akiyoshi; Amano, Masafumi; Goto, Tomoaki; Nozaki, Masumi; Meguro, Hiroshi; Kawauchi, Hiroshi

2008-06-01

Dogfish (Squalus acanthias) growth hormone (GH) was identified by cDNA cloning and protein purification from the pituitary gland. Dogfish GH cDNA encoded a prehormone of 210 amino acids (aa). Sequence analysis of purified GH revealed that the prehormone is composed of a signal peptide of 27 aa and a mature protein of 183 aa. Dogfish GH showed 94% sequence identity with blue shark GH, and also showed 37-66%, 26%, and 48-67% sequence identity with GH from osteichtyes, an agnathan, and tetrapods. The site of production was identified through immunocytochemistry to be cells of the proximal pars distalis of the pituitary gland. Dogfish GH stimulates both insulin-like growth factor-I and II mRNA levels in dogfish liver in vitro. The dogfish GH gene consisted of five exons and four introns, the same as in lamprey, teleosts such as cypriniforms and siluriforms, and tetrapods. The 5'-flanking region within 1082 bp of the transcription start site contained consensus sequences for the TATA box, Pit-1/GHF-1, CRE, TRE, and ERE. These results show that the endocrine mechanism for growth stimulation by the GH-IGF axis was established at an early stage of vertebrate evolution, and that the 5-exon-type gene organization might reflect the structure of the ancestral gene for the GH gene family.

Organochlorines and metals induce changes in the mitochondria-rich cells of fish gills: an integrative field study involving chemical, biochemical and morphological analyses.

PubMed

Fernandes, M N; Paulino, M G; Sakuragui, M M; Ramos, C A; Pereira, C D S; Sadauskas-Henrique, H

2013-01-15

Through integrating chemical, biochemical and morphological analyses, this study investigated the effects of multiple pollutants on the gill mitochondria-rich cells (MRCs) in two fish species, Astyanax fasciatus and Pimelodus maculatus, collected from five sites (FU10, FU20, FU30, FU40 and FU50) in the Furnas Hydroelectric Power Station reservoir. Water analyses revealed aluminum, iron and zinc as well as organochlorine (aldrin/dieldrin, endosulfan, heptachlor/heptachlor epoxide and metolachlor) contamination at all of the sites, with the exception of FU10. Copper, chrome, iron and zinc were detected in the gills of both species, and aldrin/dieldrin, endosulfan and heptachlor/heptachlor epoxide were detected in the gills of fish from all of the sites, with the exception of FU10. Fish collected at FU20, FU30 and FU50 exhibited numerous alterations in the surface architecture of their pavement cells and MRCs. The surface MRC density and MRC fractional area were lower in fish from FU20, FU30, FU40 and FU50 than in those from the reference site (FU10) in the winter, and some variability between the sites was observed in the summer. The organochlorine contamination at FU20 and FU50 was associated with variable changes in the MRCs and inhibition of Na(+)/K(+)-ATPase (NKA) activity, especially in P. maculatus. At FU30, the alterations in the MRCs were associated with the contaminants present, especially metals. A multivariate analysis demonstrated a positive association between the biological responses of both species and environmental contamination, indicating that under realistic conditions, a mixture of organochlorines and metals affected the MRCs by inhibiting NKA activity and inducing morphological changes, which may cause an ionic imbalance. Copyright © 2012 Elsevier B.V. All rights reserved.

The impact of organochlorines and metals on wild fish living in a tropical hydroelectric reservoir: bioaccumulation and histopathological biomarkers.

PubMed

Paulino, Marcelo Gustavo; Benze, Tayrine Paschoaletti; Sadauskas-Henrique, Helen; Sakuragui, Marise Margareth; Fernandes, João Batista; Fernandes, Marisa Narciso

2014-11-01

This study evaluates the contaminants in water and their bioaccumulation in the gills and liver of two ecologically distinct fish species, Astyanax fasciatus and Pimelodus maculatus, living in the reservoir of the Furnas hydroelectric power station located in Minas Gerais in the southeastern Brazil. The histological alterations in these organs are also examined. Water and fish were collected in June and December from five sites (site 1: FU10, site 2: FU20, site 3: FU30, site 4: FU40 and site 5: FU50) in the reservoir, and agrochemicals and metals selected based on their use in the field crops surrounding the reservoir were analyzed in the water and in the fish gills and livers. The concentrations of the organochlorines aldrin/dieldrin, endosulfan and heptachlor/heptachlor epoxide as well as the metals copper, chromium, iron and zinc in the gills and livers of both fish species were higher in June than in December; the liver accumulated higher concentrations of contaminants than the gills. The organochlorine metolachlor was detected only in the liver. The histological pattern of changes was similar in both species with regard to contaminant accumulation in the gills and liver. Fish from FU10, the least contaminated site, exhibited normal gill structure and moderate to heavy liver damage. Fish collected at FU20 to FU50, which were contaminated with organochlorines and metals, showed slight to moderate gill damage in June and irreparable liver damage in the livers in June and December. The histological changes in the gills and liver were suitable to distinguishing contaminated field sites and are therefore useful biomarkers for environmental contamination representing a biological end-point of exposure. Copyright © 2014 Elsevier B.V. All rights reserved.

Morphology-based phylogeny of the suckermouth armored catfishes, with emphasis on the Neoplecostominae (Teleostei: Siluriformes: Loricariidae).

PubMed

Pereira, Edson H L; Reis, Roberto E

2017-05-11

A phylogenetic study of the Loricariidae with emphasis on the Neoplecostominae is presented based on a maximum parsimony analysis of 268 phenotypic characters encompassing osteology, arthrology, and external morphology. Results support previous hypotheses of the monophyly of the Neoplecostominae and each of the included genera: Hirtella, Isbrueckerichthys, Kronichthys, Neoplecostomus, Pareiorhaphis, and Pareiorhina. In addition, previously undiscovered diversity was revealed within the subfamily as an additional genus-level taxon, herein described as Euryochus. Relationships among neoplecostomine genera are: (Kronichthys (Euryochus ((Hirtella + Pareiorhaphis) (Pareiorhina (Isbrueckerichthys + Neoplecostomus))))). Additional undescribed diversity was also detected among most neoplecostomine genera and the Hypoptopomatinae. In addition, recently discovered genera Nannoplecostomus and Microplecostomus were included in the analysis, and were identified as sequential sister-taxa to Neoplecostominae + Hypoptopomatinae, which are currently not included in any subfamily and regarded as incertae sedis in Loricariidae. The three species of Lithogenes were included in an encompassing phylogenetic analysis for the first time, and were identified as a monophyletic unit and sister group to all remaining loricariids. The other loricariid subfamilies were also corroborated as monophyletic, and presented the following interrelationships (Lithogeninae (Delturinae (Loricariinae (Hypostominae (Nannoplecostomus (Microplecostomus (Hypoptopomatinae + Neoplecostominae). The Neoplecostominae and its genera are phylogenetically diagnosed, and hypothesized relationships are compared to those of previous morphological and molecular phylogenetic studies.

Multilocus molecular phylogeny of the suckermouth armored catfishes (Siluriformes: Loricariidae) with a focus on subfamily Hypostominae.

PubMed

Lujan, Nathan K; Armbruster, Jonathan W; Lovejoy, Nathan R; López-Fernández, Hernán

2015-01-01

The Neotropical catfish family Loricariidae is the fifth most species-rich vertebrate family on Earth, with over 800 valid species. The Hypostominae is its most species-rich, geographically widespread, and ecomorphologically diverse subfamily. Here, we provide a comprehensive molecular phylogenetic reappraisal of genus-level relationships in the Hypostominae based on our sequencing and analysis of two mitochondrial and three nuclear loci (4293bp total). Our most striking large-scale systematic discovery was that the tribe Hypostomini, which has traditionally been recognized as sister to tribe Ancistrini based on morphological data, was nested within Ancistrini. This required recognition of seven additional tribe-level clades: the Chaetostoma Clade, the Pseudancistrus Clade, the Lithoxus Clade, the 'Pseudancistrus' Clade, the Acanthicus Clade, the Hemiancistrus Clade, and the Peckoltia Clade. Results of our analysis, which included type- and non-type species for every valid genus in Hypostominae, support the reevaluation and restriction of several historically problematic genera, including Baryancistrus, Cordylancistrus, Hemiancistrus, and Peckoltia. Much of the deep lineage diversity in Hypostominae is restricted to Guiana Shield and northern Andean drainages, with three tribe-level clades still largely restricted to the Guiana Shield. Of the six geographically widespread clades, a paraphyletic assemblage of three contain lineages restricted to drainages west of the Andes Mountains, suggesting that early diversification of the Hypostominae predated the late Miocene surge in Andean uplift. Our results also highlight examples of trophic ecological diversification and convergence in the Loricariidae, including support for three independent origins of highly similar and globally unique morphological specializations for eating wood. Copyright © 2014 Elsevier Inc. All rights reserved.

Molecular phylogeny of the highly diversified catfish subfamily Loricariinae (Siluriformes, Loricariidae) reveals incongruences with morphological classification.

PubMed

Covain, Raphaël; Fisch-Muller, Sonia; Oliveira, Claudio; Mol, Jan H; Montoya-Burgos, Juan I; Dray, Stéphane

2016-01-01

The Loricariinae belong to the Neotropical mailed catfish family Loricariidae, the most species-rich catfish family. Among loricariids, members of the Loricariinae are united by a long and flattened caudal peduncle and the absence of an adipose fin. Despite numerous studies of the Loricariidae, there is no comprehensive phylogeny of this morphologically highly diversified subfamily. To fill this gap, we present a molecular phylogeny of this group, including 350 representatives, based on the analysis of mitochondrial and nuclear genes (8426 positions). The resulting phylogeny indicates that Loricariinae are distributed into two sister tribes: Harttiini and Loricariini. The Harttiini tribe, as classically defined, constitutes a paraphyletic assemblage and is here restricted to the three genera Harttia, Cteniloricaria, and Harttiella. Two subtribes are distinguished within Loricariini: Farlowellina and Loricariina. Within Farlowellina, the nominal genus formed a paraphyletic group, as did Sturisoma and Sturisomatichthys. Within Loricariina, Loricaria, Crossoloricaria, and Apistoloricaria are also paraphyletic. To solve these issues, and given the lack of clear morphological diagnostic features, we propose here to synonymize several genera (Quiritixys with Harttia; East Andean members of Crossoloricaria, and Apistoloricaria with Rhadinoloricaria; Ixinandria, Hemiloricaria, Fonchiiichthys, and Leliella with Rineloricaria), to restrict others (Crossoloricaria, and Sturisomatichthys to the West Andean members, and Sturisoma to the East Andean species), and to revalidate the genus Proloricaria. Copyright © 2015 Elsevier Inc. All rights reserved.

The non-monotypic status of the neotropical fish genus Hemiodontichthys (Siluriformes, Loricariidae) evidenced by genetic approaches.

PubMed

Carvalho, Margarida Lima; Costa Silva, Guilherme José da; Melo, Silvana; Ashikaga, Fernando Yuldi; Shimabukuro-Dias, Cristiane Kioko; Scacchetti, Priscilla Cardim; Devidé, Renato; Foresti, Fausto; Oliveira, Claudio

2018-01-31

The combination of cytogenetic and molecular data with those traditionally obtained in areas like systematics and taxonomy created interesting perspectives for the analysis of natural populations under different aspects. In this context, this study aimed to evaluate the genetic differentiation among populations of the genus Hemiodontichthys Bleeker, 1862, through combined genetic techniques and included the analysis of populations sampled in the Araguaia River, Guamá River, Madeira River and two populations from the Purus River. Hemiodontichthys samples from the two localities in Purus River were also karyotyped in order to address the degree of chromosomal variation between populations. Through GMYC analysis of the COI tree, the patterns of genetic variation among local populations revealed to be higher than the ones found among distinct species from other genera of the subfamily Loricariinae, suggesting the existence of probable four cryptic species in this genus. The possible existence of a species complex in the genus is corroborated by the different cytogenetic patterns between Hemiodontichthys sp. 1 and sp. 2, revealing the necessity of a deep taxonomic review of the group.

A new distinctively banded-species of Panaqolus (Siluriformes: Loricariidae) from the western Amazon Basin in Peru.

PubMed

Lujan, Nathan K; Steele, Sarah; Velasquez, Miquel

2013-01-01

Panaqolus albivermis is described as a new species based on four specimens from the San Alejandro River, a tributary of the upper Ucayali River in central Peru. Panaqolus albivermis is diagnosed from all other Panaqolus except P. maccus by having head, body, and fins with widely separated small white to yellow spots, vermiculations, and/or thin oblique bands on a black base (vs. exclusively small white to yellow spots on a black base in P. alboinaculatus, generally broad oblique bands of alternating light to dark brown in P. changae, P. gnomus, P purusiensis, and a uniformly dark gray to black body color in P. dentex, P. koko, and P. nocturnus); P. albivernis can be diagnosed from P. maccus by having a black base color (vs. brown), by having parallel dentary tooth cups (vs. acute intermandibular tooth cup angle), and by having a larger known adult body size (95.8 mm SL vs. 84.8).

Molecular analysis reveals hidden diversity in Zungaro (Siluriformes: Pimelodidade): a genus of giant South American catfish.

PubMed

Pires, Antonio A; Ramirez, Jorge L; Galetti, Pedro M; Troy, Waldo P; Freitas, Patricia D

2017-06-01

The genus Zungaro contains some of the largest catfish in South America. Two valid species are currently recognized: Zungaro jahu, inhabiting the Paraná and Paraguay basins, and Zungaro zungaro, occurring in the Amazonas and Orinoco basins. Analysing Zungaro specimens from the Amazonas, Orinoco, Paraguay and Paraná basins, based on the sequencing of COI and D-loop, we found at least three MOTUs, indicating the existence of hidden diversity within this fish group. Considering the ecological and economic values of this fish, our results are surely welcomed for its conservation, disclosing new findings on its diversity and pointing out the necessity for a detailed taxonomic revision.

Morphology and 18S rDNA of Henneguya gurlei (Myxosporea) from Ameiurus nebulosus (Siluriformes) in North Carolina.

PubMed

Iwanowicz, Luke R; Iwanowicz, Deborah D; Pote, Linda M; Blazer, Vicki S; Schill, William B

2008-02-01

Henneguya gurlei was isolated from Ameiurus nebulosus captured in North Carolina and redescribed using critical morphological features and 18S small-subunit ribosomal RNA (SSU rDNA) gene sequence. Plasmodia are white, spherical, or subspherical, occur in clusters, measure up to 1.8 mm in length, and are located on the dorsal, pectoral, and anal fins. Histologically, plasmodia are located in the dermis and subdermally, and the larger cysts disrupt the melanocyte pigment layer. The spore body is lanceolate, 18.2 +/- 0.3 microm (range 15.7-20.3) in length, and 5.4 +/- 0.1 microm (range 3.8-6.1) in width in valvular view. The caudal appendages are 41.1 +/- 1.1 microm (range 34.0-49.7) in length. Polar capsules are pyriform and of unequal size. The longer polar capsule measures 6.2 +/- 0.1 microm (range 5.48-7.06), while the shorter is 5.7 +/- 0.1 microm (range 4.8-6.4) in length. Polar capsule width is 1.2 +/- 0.03 microm (range 1.0-1.54). The total length of the spore is 60.9 +/- 1.2 microm (range 48.7-68.5). Morphologically, this species is similar to other species of Henneguya that are known to infect ictalurids. Based on SSU rDNA sequences, this species is most closely related to H. exilis and H. ictaluri, which infect Ictalurus punctatus.

Morphology and 18S rDNA of Henneguya gurlei (Myxosporea) from Ameiurus nebulosus (Siluriformes) in North Carolina

USGS Publications Warehouse

Iwanowicz, L.R.; Iwanowicz, D.D.; Pote, L.M.; Blazer, V.S.; Schill, W.B.

2008-01-01

Henneguya gurlei was isolated from Ameiurus nebulosus captured in North Carolina and redescribed using critical morphological features and 18S small-subunit ribosomal RNA (SSU rDNA) gene sequence. Plasmodia are white, spherical, or subspherical, occur in clusters, measure up to 1.8 mm in length, and are located on the dorsal, pectoral, and anal fins. Histologically, plasmodia are located in the dermis and subdermally, and the larger cysts disrupt the melanocyte pigment layer. The spore body is lanceolate, 18.2 ?? 0.3 ??m (range 15.7-20.3) in length, and 5.4 ?? 0.1 ??m (range 3.8-6.1) in width in valvular view. The caudal appendages are 41.1 ?? 1.1 ??m (range 34.0-49.7) in length. Polar capsules are pyriform and of unequal size. The longer polar capsule measures 6.2 ?? 0.1 ??m (range 5.48-7.06), while the shorter is 5.7 ?? 0.1 ??m (range 4.8-6.4) in length. Polar capsule width is 1.2 ?? 0.03 ??m (range 1.0-1.54). The total length of the spore is 60.9 ?? 1.2 ??m (range 48.7-68.5). Morphologically, this species is similar to other species of Henneguya that are known to infect ictalurids. Based on SSU rDNA sequences, this species is most closely related to H. exilis and H. ictaluri, which infect Ictalurus punctatus. ?? American Society of Parasitologists 2008.

Molecular phylogeny and biogeographic history of the armored neotropical catfish subfamilies hypoptopomatinae, neoplecostominae and otothyrinae (siluriformes: loricariidae).

PubMed

Roxo, Fábio F; Albert, James S; Silva, Gabriel S C; Zawadzki, Cláudio H; Foresti, Fausto; Oliveira, Claudio

2014-01-01

The main objectives of this study are estimate a species-dense, time-calibrated molecular phylogeny of Hypoptopomatinae, Neoplecostominae, and Otothyrinae, which together comprise a group of armoured catfishes that is widely distributed across South America, to place the origin of major clades in time and space, and to demonstrate the role of river capture on patterns of diversification in these taxa. We used maximum likelihood and Bayesian methods to estimate a time-calibrated phylogeny of 115 loricariid species, using three mitochondrial and one nuclear genes to generate a matrix of 4,500 base pairs, and used parametric biogeographic analyses to estimate ancestral geographic ranges and to infer the effects of river capture events on the geographic distributions of these taxa. Our analysis recovered Hypoptopomatinae, Neoplecostominae, and Otothyrinae as monophyletic with strong statistical support, and Neoplecostominae as more closely related to Otothyrinae than to Hypoptopomatinae. Our time-calibrated phylogeny and ancestral-area estimations indicate an origin of Hypoptopomatinae, Neoplecostominae, and Otothyrinae during the Lower Eocene in the Atlantic Coastal Drainages, from which it is possible to infer several dispersal events to adjacent river basins during the Neogene. In conclusion we infer a strong influence of river capture in: (1) the accumulation of modern clade species-richness values; (2) the formation of the modern basin-wide species assemblages, and (3) the presence of many low-diversity, early-branching lineages restricted to the Atlantic Coastal Drainages. We further infer the importance of headwater stream capture and marine transgressions in shaping patterns in the distributions of Hypoptopomatinae, Neoplecostominae and Otothyrinae throughout South America.

Pareiorhaphis vetula, a new armored catfish from the headwaters of the Rio Doce basin, Brazil (Siluriformes: Loricariidae).

PubMed

Pereira, Edson H L; Lehmann, Pablo A; Reis, Roberto E

2016-07-28

A new species of Pareiorhaphis is described from the upper Rio Doce basin. The description is based on a series of specimens recently collected in small headwater tributaries to the Rio Guanhães, a tributary of the Rio Santo Antonio, left bank of the Rio Doce in Minas Gerais State, eastern Brazil. Pareiorhaphis vetula, new species, is a small loricariid catfish with dark brown spots irregularly scattered over a brown background on the dorsal surface of body and along flanks. The new species differs from all other Pareiorhaphis species by having the maxillary barbel completely adnate to the lower lip and by adult males possessing a particularly elongate, sharply pointed, conical urogenital papilla. In addition, Pareiorhaphis vetula is further distinguished from most congeners by having a shorter pelvic-fin spine, or by possessing more numerous premaxillary teeth, and by lacking a dorsal-fin spinelet. A comparison with congeners P. nasuta, P. scutula and P. proskynita, which also occur in headwater streams of the Rio Doce basin is also presented.

Chromosomal characterization of armored catfish Harttia longipinna (Siluriformes, Loricariidae): first report of B chromosomes in the genus.

PubMed

Blanco, Daniel Rodrigues; Vicari, Marcelo Ricardo; Artoni, Roberto Ferreira; Traldi, Josiane Baccarin; Moreira-Filho, Orlando

2012-09-01

The B chromosomes are accessory elements that are widely distributed among eukaryotic genomes and often show non-Mendelian inheritance. They are considered dispensable for the growth, development, and reproduction of organisms. Some studies have suggested that these elements may affect sex determination. Harttia is a small armored catfish genus that shows sexual dimorphism, including hypertrophied odontodes on the pectoral fin spines and along the margins of the snout in mature males. They exhibit considerable karyotypic diversity with diploid number (2n) variation and heteromorphic sex system in H. carvalhoi. To date, no occurrences of B chromosomes in the Harttia genus were detected and no relation to sexual differentiation in Neotropical fish has been determined. To determine the validity of this claim, the present paper characterized specimens of Harttia longipinna by classical and molecular cytogenetic methods. The 2n found was 58 (16m + 12sm + 16st + 14a), but of the 50 specimens analyzed (30 male and 20 female), 23 specimens (16 males and seven females) show an intra-individual from 0 to 2 micro B chromosomes. The B chromosomes were completely heterochromatic. The single NORs were shown in the first acrocentric pair with silver staining and 18S rDNA probing. FISH performed with 5S rDNA probe showed a single cistron in the proximal region of the short arm of a small metacentric pair. Thus, the cytogenetic data obtained in this study of H. longipinna highlight the karyotypic diversity found within the genus Harttia, and represent the first description of B chromosomes for this genus.

Mechanisms of chromosomal evolution and its possible relation to natural history characteristics in Ancistrus catfishes (Siluriformes: Loricariidae).

PubMed

de Oliveira, R R; Feldberg, E; Dos Anjos, M B; Zuanon, J

2009-12-01

Ancistrus is the most speciose genus of the tribe Ancistrini, with 58 valid species and many yet to be described. Cytogenetic studies were conducted on five apparently undescribed species from the Amazon basin, which showed different diploid numbers: Ancistrus sp. Purus (2n = 34); Ancistrus sp. Macoari (2n = 46); Ancistrus sp. Dimona (2n = 52); Ancistrus sp. Vermelho (2n = 42) and Ancistrus sp. Trombetas (2n = 38). All species possessed only one pair of NOR-carrying chromosomes, but with extensive variation in both the location on the chromosome as well as in the position of the ribosomal sites on the karyotype. The karyotypic evolution of Ancistrus species seems to be based on chromosomal rearrangements, with a tendency to a reduction of the diploid number. Two new instances of XX/XY sex chromosomes for Ancistrus species, based on the heteromorphism in the male karyotype, were also recorded. The large karyotypic diversity among Ancistrus species may be related to biological and behavioural characteristics of these fish that include microhabitat preferences, territoriality and specialized reproductive tactics. These characteristics may lead to a fast rate of fixation of chromosomal mutations and eventually speciation across the basin.

Neogene tropical sea catfish (Siluriformes; Ariidae), with insights into paleo and modern diversity within northeastern South America

NASA Astrophysics Data System (ADS)

Aguilera, Orangel; Marceniuk, Alexandre Pires

2018-03-01

Herein we describe five new fossil species of the catfish family Ariidae: †Amphiarius paleoorinocoensis, †Ariopsis ariopsilus, †Bagre urumacoensis, †Sciades latissimum and †Sciades peregrinus from the late Miocene Urumaco Formation in Venezuela, South America. These identifications were based on comparison of morphological characters between the fossil skulls and the skulls of extant specimens from tropical America. The extant ariids from the Atlantic plume of the Orinoco-Amazon rivers reveal close taxonomic relationship to the fossil species. †Amphiarius paleoorinocoensis n. sp. and †Aspistor verumquadriscutis are closely related to Amphiarius rugispinis, Amphiarius phrygiatus and Aspistor quadriscutis, species endemic to areas under the influence of the Orinoco-Amazon plume. Another genus whose extant species are almost exclusively found in this region of the Atlantic is Sciades. Nevertheless, †Sciades latissimus n. sp. and †Sciades peregrinus n. sp., are closely related with Sciades dowii, found in the Pacific. This condition supports the extinction of Sciades dowii lineage in the Atlantic. The fossil †Ariopsis ariopsilus n. sp. shares many characters with extant species of the genus, which does not occur in the Amazon delta and which has no representative species in the Atlantic plume. The close relationship of †Bagre urumacoensis n. sp. to Bagre aff. marinus suggests a marine paleoenvironment with average to higher salinities. These new fossil catfish specimens from the Urumaco Formation suggest that they are ancestral lineages from both the Orinoco-Amazon Atlantic plume influence area (Aspistor and Amphiarius) and the Caribbean-Western Pacific (Ariopsis), and extinct lineage of Sciades from the Atlantic.

New species of Parotocinclus (Siluriformes: Loricariidae) from coastal drainages of Rio de Janeiro, southeastern Brazil.

PubMed

Roxo, Fábio F; Melo, Bruno F; Silva, Gabriel S C; Oliveira, Claudio

2017-02-15

A new species of Parotocinclus is described from tributaries of rio São João, an Atlantic coastal river of Rio de Janeiro, southeastern Brazil. The new species is distinguished from its congeners by the possession of a triangular patch of dark pigmentation on the anterior portion of the dorsal-fin base, a fully developed adipose fin, complete exposure of the ventral surface of the pectoral girdle, and a distinctive pigmentation pattern of the caudal fin. The caudal fin has a hyaline background with a large black blotch covering its anterior portion, tapering irregularly through distal portions of the ventral lobe with a hyaline rounded area, and a small patch of dark pigmentation on distal portions of the dorsal lobe.

New species of the Pseudancistrus barbatus group (Siluriformes, Loricariidae) with comments on its biogeography and dispersal routes

PubMed Central

Silva, Gabriel de Souza da Costa e; Roxo, Fábio Fernandes; Britzke, Ricardo; Oliveira, Claudio

2014-01-01

Abstract A new species of Pseudancistrus is described from the Tapajós Basin, and assigned to the P. barbatus group by having hypertrophied odontodes along the snout and lacking evertible cheek plates. The new species is distinguished from other species in that group (P. barbatus, P. corantijniensis, P. depressus and P. nigrescens) by its pattern of spots, length and color of snout odontodes, greater head depth, cleithral width, anal-fin spine length, peduncle depth and internares width. Molecular phylogenetic results corroborate placement of the new species in the Pseudancistrus barbatus group which is otherwise distributed in the Xingu Basin and rivers draining the Guyana Shield into the Atlantic Ocean. Topology tests strongly reject alternative hypotheses supporting close relationships with Guyanancistrus, Lithoxancistrus or the species Pseudancistrus pectegenitor, P. sidereus and P. genisetiger. Additionally, we propose two hypotheses on the distribution of the new species in the rio Tapajós, a Brazilian Shield drainage. The first one proposes that ancestral stock of the P. barbatus group was widely distributed throughout rivers draining the Guyana and Brazilian shields, and the species P. zawadzkii and Pseudancistrus sp. L17 are in the limit of the distribution for the group in Tapajós and Xingu rivers. The second hypothesis proposes that ancestral stock of the P. barbatus group was restricted to Guyana Shield rivers, and that headwater capture events permitted several dispersal routs through Guyana and Amazon rivers, permitted that the ancestral lineages of Pseudancistrus sp. L17 and P. zawadzkii reached the rivers of Amazon basin. PMID:24843279

Molecular Phylogeny and Biogeographic History of the Armored Neotropical Catfish Subfamilies Hypoptopomatinae, Neoplecostominae and Otothyrinae (Siluriformes: Loricariidae)

PubMed Central

Roxo, Fábio F.; Albert, James S.; Silva, Gabriel S. C.; Zawadzki, Cláudio H.; Foresti, Fausto; Oliveira, Claudio

2014-01-01

The main objectives of this study are estimate a species-dense, time-calibrated molecular phylogeny of Hypoptopomatinae, Neoplecostominae, and Otothyrinae, which together comprise a group of armoured catfishes that is widely distributed across South America, to place the origin of major clades in time and space, and to demonstrate the role of river capture on patterns of diversification in these taxa. We used maximum likelihood and Bayesian methods to estimate a time-calibrated phylogeny of 115 loricariid species, using three mitochondrial and one nuclear genes to generate a matrix of 4,500 base pairs, and used parametric biogeographic analyses to estimate ancestral geographic ranges and to infer the effects of river capture events on the geographic distributions of these taxa. Our analysis recovered Hypoptopomatinae, Neoplecostominae, and Otothyrinae as monophyletic with strong statistical support, and Neoplecostominae as more closely related to Otothyrinae than to Hypoptopomatinae. Our time-calibrated phylogeny and ancestral-area estimations indicate an origin of Hypoptopomatinae, Neoplecostominae, and Otothyrinae during the Lower Eocene in the Atlantic Coastal Drainages, from which it is possible to infer several dispersal events to adjacent river basins during the Neogene. In conclusion we infer a strong influence of river capture in: (1) the accumulation of modern clade species-richness values; (2) the formation of the modern basin-wide species assemblages, and (3) the presence of many low-diversity, early-branching lineages restricted to the Atlantic Coastal Drainages. We further infer the importance of headwater stream capture and marine transgressions in shaping patterns in the distributions of Hypoptopomatinae, Neoplecostominae and Otothyrinae throughout South America. PMID:25148406

Hepatic retinoid levels in seven fish species (teleosts) from a tropical coastal lagoon receiving effluents from iron-ore mining and processing.

PubMed

Pereira, Adriana A; van Hattum, Bert; Brouwer, Abraham

2012-02-01

The present study was undertaken to investigate the possible effects of Fe and trace element exposure on hepatic levels of retinoids in seven fish species. Concentrations of retinoids were measured in fish collected from a coastal lagoon in Brazil that receives effluents from an iron-ore mining and processing plant. Fish from nearby coastal lagoons were also included to assess possible differences related to chemical exposure. Results indicated considerable differences in hepatic retinoid composition among the various species investigated. The most striking differences were in retinol and derivative-specific profiles and in didehydro retinol and derivative-specific profiles. The Perciformes species Geophagus brasiliensis, Tilapia rendalli, Mugil liza, and Cichla ocellaris and the Characiforme Hoplias malabaricus were characterized as retinol and derivative-specific, while the Siluriformes species Hoplosternum littorale and Rhamdia quelen were didehydro retinol and derivative-specific fish species. A negative association was observed between Al, Pb, As, and Cd and hepatic didehydro retinoid levels. Fish with higher levels of hepatic Fe, Cu, and Zn showed unexpectedly significant positive correlations with increased hepatic retinol levels. This finding, associated with the positive relationships between retinol and retinyl palmitate with lipid peroxidation, may suggest that vitamin A is mobilized from other tissues to increase hepatic antioxidant levels for protection against oxidative damage. These data show significant but dissimilar associations between trace element exposure and hepatic retinoid levels in fish species exposed to iron-ore mining and processing effluents, without apparent major impacts on fish health and condition. Copyright © 2011 SETAC.

Testing for the Occurrence of Selective Episodes During the Divergence of Otophysan Fishes: Insights from Mitogenomics.

PubMed

D'Anatro, Alejandro; Giorello, Facundo; Feijoo, Matías; Lessa, Enrique P

2017-04-01

How natural selection shapes biodiversity constitutes a topic of renewed interest during the last few decades. The division Otophysi comprises approximately two-thirds of freshwater fish diversity and probably underwent an extensive adaptive radiation derived from a single invasion of the supercontinent Pangaea, giving place to the evolution of the main five Otophysan lineages during a short period of time. Little is known about the factors involved in the processes that lead to lineage diversification among this group of fishes and identifying directional selection acting over protein-coding genes could offer clues about the processes acting on species diversification. The main objective of this study was to explore the otophysan mitochondrial genome evolution, in order to account for the possible signatures of selective events in this lineage, and to explore for the functional connotations of these molecular substitutions. Mainly, three different approaches were used: the "ω-based" BS-REL and MEME methods, implemented in the DATAMONKEY web server, and analysis of selection on amino acid properties, implemented in the software TreeSAAP. We found evidence of selective episodes along several branches of the evolutionary history of othophysan fishes. Analyses carried out using the BS-REL algorithm suggest episodic diversifying selection at basal branches of the otophysan lineage, which was also supported by analyses implemented in MEME and TreeSAAP. These results suggest that throughout the Siluriformes radiation, an important number of adaptive changes occurred in their mitochondrial genome. The metabolic consequences and ecological correlates of these molecular substitutions should be addressed in future studies.

Untangling convoluted taxonomy of Chambriella Rego, Chubb & Pavanelli, 1999 (Cestoda: Proteocephalidae), with erection of Riggenbachiella n. g. and the description of a new species from pimelodid catfishes in the Neotropical Region.

PubMed

Alves, Philippe Vieira; de Chambrier, Alain; Luque, José Luis; Scholz, Tomáš

2017-03-01

As part of a complex revision of proteocephalid cestodes parasitic in freshwater bony fishes of the Neotropical Region, the genus Chambriella Rego, Chubb & Pavanelli, 1999 is redefined based on detailed examination of type-specimens and newly collected material of both nominal species of the genus. This examination revealed that the type-species C. agostinhoi (Pavanelli & Santos, 1992) from Zungaro jahu (Ihering) (type-host) and Z. zungaro (Humboldt) is indistinguishable from Lenhataenia megacephala (Woodland, 1934) from Sorubimichthys planiceps (Spix & Agassiz) (all hosts Siluriformes: Pimelodidae), the type- and only species of the genus. New molecular data (partial sequences of the large subunit nuclear ribosomal RNA gene) support the conspecificity of these taxa. As a result, Lenhataenia de Chambrier & Scholz, 2008 becomes a junior synonym of Chambriella and its type-species, C. agostinhoi, a junior synonym of C. megacephala (Woodland, 1934) n. comb. The second species of Chambriella, C. paranaensis (Pavanelli & Rego, 1989) from Hemisorubim platyrhynchos (Valenciennes), is transferred to a new genus, Riggenbachiella n. g., as R. paranaense (Pavanelli & Rego, 1989) n. comb. Riggenbachiella amazonense n. sp. (syn. Chambriella sp. of de Chambrier & Scholz, 2008) from S. planiceps (type-host), Phractocephalus hemioliopterus (Bloch & Schneider) and Z. zungaro is described and designated as the type-species of the new genus. Riggenbachiella n. g. is placed in the subfamily Monticelliinae Mola, 1929, because of the cortical position of the testes, ovary, vitelline follicles and uterus, and is mainly characterised by the possession of a sigmoid cirrus-sac with voluminous, chambered internal seminal vesicle, and bi-loculate suckers.

Microlepidogaster arachas, a new species of hypoptopomatine catfish (Siluriformes: Loricariidae) from the upper rio Paraná basin, Brazil.

PubMed

Martins, Fernanda O; Calegari, Bárbara B; Langeani, Francisco

2013-01-22

Microlepidogaster arachas Martins, Calegari & Langeani, sp. nov., a new Hypoptopomatinae, is described from the upper rio Paraná basin. The new species is distinguished from M. longicolla and M. dimorpha by having the anterior portion of the compound supraneural plus first dorsal-fin proximal radial contacting the neural spine of the ninth vertebra. The new species differs from M. perforatus by having 18-29 dentary teeth; median series of lateral plates complete, reaching caudal-peduncle end, and continuous lateral line; and 20-24 mid-dorsal plates. Microlepidogaster arachas is further distinguished from its congeners by several other osteological features.

Functional and evolutionary anatomy of the African suckermouth catfishes (Siluriformes: Mochokidae): convergent evolution in Afrotropical and Neotropical faunas.

PubMed

Geerinckx, Tom; De Kegel, Barbara

2014-08-01

Of those fishes scraping food off substrates and using head parts in substrate attachment for station-holding, the catfish families Loricariidae, Astroblepidae and Mochokidae display the most dramatically adapted morphologies. Loricariidae and Astroblepidae, living in the Neotropical freshwaters, exclusively contain suckermouth catfish species, and their anatomy and head kinematics have already been studied into detail. Among Mochokidae, living in the tropical freshwaters of Africa, only the chiloglanidine subfamily has a sucker mouth, and occupies similar niches in Africa as both Neotropical families do in South America. Having derived from relatively unrelated catfish ancestors, their anatomy is poorly known, and the nature of their scraping and station-holding capabilities is not known at all. This paper provides details on the chiloglanidine head anatomy and function (relating their anatomy to that of the non-suckermouth Mochokidae), and compares this Afrotropical suckermouth taxon with both Neotropical suckermouth families. It identifies both convergences and differing anatomical and kinematic solutions to the same key needs of food-scraping and station-holding suckermouth fishes. Chiloglanidine mochokids differ from both Neotropical families in having less mobile jaws, with an upper jaw assisting more in station-holding than in feeding. They share the highly mobile lower lip with both Neotropical taxa, although the configuration of the intermandibular/protractor hyoidei muscle system, changing the volume of the sucker-disc cavity, differs in all three taxa. Chiloglanidines have a single, posterior inflow opening into this cavity, whereas Loricariidae have two lateral openings, and Astroblepidae have none, using an opercular incurrent opening instead. The chiloglanidine buccal valve system consists of two passive valves, as in Astroblepidae. Although less diverse in number of genera and species, this Afrotropical suckermouth taxon possesses the anatomical and kinematic key elements allowing a successful occupation of a niche similar to the one found in the Loricariidae + Astroblepidae clade. © 2014 Anatomical Society.

Systematics and biogeography of New World sea catfishes (Siluriformes: Ariidae) as inferred from mitochondrial, nuclear, and morphological evidence.

PubMed

Betancur-R, Ricardo; Acero P, Arturo; Bermingham, Eldredge; Cooke, Richard

2007-10-01

Ariid or sea catfishes include around 150 species that inhabit marine, brackish, and freshwater environments along world's tropical and subtropical continental shelves. Phylogenetic relationships for 46 New World and three Old World species of ariids were hypothesized using maximum parsimony and Bayesian inference reconstruction criteria on 2842 mitochondrial (cytochrome b, ATP synthase 8 and 6, ribosomal 12S and 16S) and 978 nuclear (rag2) nucleotide sites. The molecular topologies were compared to a previously compiled morphological dataset that was expanded herein to a total of 25 ariid species and 55 characters. Mitochondrial data yielded clades highly resolved at subfamilial, generic, and intrageneric levels. Nuclear rag2 reconstructions showed poor resolution at supra- and intrageneric levels, but provided support for the monophyly of most genera (except Ariopsis and Cathorops) as well as for the subfamilial clades. The hypothesized phylogeny derived from the morphological data was congruent with the molecular topologies at infrafamilial and generic levels. As indicated by the statistical tests of topological congruence, Kailola's phylogenetic hypothesis of ariids based on anatomical data is significantly different from our molecular trees. All reconstructions agree in the division of the Ariidae into two subfamilies, the Ariinae and the monogeneric Galeichthyinae. Basal ariine resolution was negligible suggesting that early diversification events occurred rapidly. The three Indo-Pacific taxa were grouped into a clade, but New World ariines were never recovered as monophyletic. We provide a revised classification for New World ariines examined, which is consistent with the molecular and the morphological evidence. Our classification scheme includes the genera Ariopsis, Bagre, Cathorops, Notarius, Potamarius, and Sciades, and the description of two new genus-level taxa (Occidentarius n. gen and Precathorops n. subgen.). We also hypothesize plausible biogeographic scenarios that explain distributional patterns of major ariid lineages. Diversification of the predominantly circumtropical ariines likely occurred throughout the Tethys Sea, whereas speciation events in the subtropical galeichthyines were probably tied to the southern coast of Gondwana.

Morphology and histology of male and female reproductive systems in the inseminating species Scoloplax distolothrix (Ostariophysi: Siluriformes: Scoloplacidae).

PubMed

Spadella, Maria Angélica; Oliveira, Claudio; Quagio-Grassiotto, Irani

2008-09-01

The morphology and histology of male and female reproductive systems were examined in Scoloplax distolothrix. Internal insemination was documented in this species by the presence of sperm within the ovaries. Mature males and females have elongated genital papillae, exhibiting a tubular shape in males and a plain heart-shape with two median protuberances in females. The testes are two elongated structures that converge ventrally, under the intestine, towards the genital papilla. They are joined at the caudal end, forming an ovoid single chamber for sperm storage. Secretory regions were not observed. In the lumen of the testicular tubules, spermatozoa can be tightly packed along their lengths, but do not constitute a spermatozeugmata. The lumen of the sperm storage chamber and spermatic duct are filled with free spermatozoa without the accompanying secretions. The ovaries are bird-wing shaped, saccular structures that converge ventrally under the intestine, towards the genital papilla. They are joined at the caudal end, forming a tubular chamber possibly destined for oocyte storage. An oviduct with an irregular outline connects the chamber to the tubular region of the genital papilla. No distinct sperm storage structure was found in the ovaries. The unique male and female genital papillae suggest that these structures are associated with the reproductive mode in scoloplacids, representing evidence for insemination. The occurrence of free spermatozoa, without the accompanying secretions and not arranged in a spermatozeugmata can be associated with the presence of a tubular male genital papilla for sperm transfer to the female genital tract. This reinforces the idea that sperm packets are not necessary for all inseminating species. The male reproductive system in scoloplacids is very different from that in auchenipterids, a second catfish family with insemination, which indicates that the occurrence of insemination is not connected to the internal morphology of reproductive organs.

Heavy metal profile of water, sediment and freshwater cat fish, Chrysichthys nigrodigitatus (Siluriformes: Bagridae), of Cross River, Nigeria.

PubMed

Ayotunde, Ezekiel Olatunji; Offem, Benedict Obeten; Ada, Fidelis Bekeh

2012-09-01

Cross River serves as a major source of drinking water, transportation, agricultural activities and fishing in Cross River State, Nigeria. Since there is no formal control of effluents discharged into the river, it is important to monitor the levels of metals contaminants in it, thus assessing its suitability for domestic and agricultural use. In order to determine this, three sampling stations designated as Ikom (Station I), Obubra Ogada (Station II) and Calabar (Station III) were randomly selected to study. For this, ten samples of the freshwater Silver Catfish (Chryshchythys nigrogitatus) (29.4-39.5cm SL, 310-510g), sediment and water were collected from each sampling Station from June 2009-June 2010. The heavy metals profiles ofZn, Cu, Fe, Co, Pb, Cd and Cr, in water, sediments and fish muscle were analyzed by atomic absorption spectrophotometry (AAS). In fish, the heavy metals concentration was found to be Cu>Fe>Zn>Cu>Pb>Cd>Co; the highest mean concentration of Copper (0.297 +/- 0.022 microg/g), Cadmium (0.011 +/- 0.007 microg/g), Iron (0.371 +/- 0.489 microg/g), Lead (0.008 +/- 0.008 microg/g), were determined for the fish. In water, the order was found to be Fe>Pb>Zn>Cu>Cr>Cd>Co; the highest mean concentration of Iron (0.009 +/- 0.00) microg/g), Copper (0.015 +/- 0.01 microg/g), Lead (0.0002 +/- 0.00 microg/g) Cadmium (0.0006 +/- 0.001 microg/g), Zinc (0.0036 +/- 0.003 microg/g), were observed in the surface water, respectively. The highest mean concentration of Copper (0.037 +/- 0.03 microg/g), Iron (0.053 +/- 0.04 microg/g), Lead (0.0002 +/- 0.00 microg/g), Cobalt (0.0002 +/- 0.00 microg/g), Cadmium (0.0006 +/- 0.001 microg/g) and Zinc (.009 +/- 0.0015 microg/g) was observed in the bottom water. In sediments, the concentration order found was Zn>Fe>Cu>Pb>Co>Cd; the highest mean concentration of 0.057 +/- 0.04 microg/g, 0.043 +/- 0.03 microg/g, 0.0006 +/- 0.00 microg/g, 0.0002 +/- 0.00 microg/g, 0.0009 +/- 0.00 microg/g, 0.099 +/- 0.00404 microg/g in Iron, Copper, Lead, Cobalt, Cadmium and Zinc were observed in the sediment, respectively; Chromium was not detected in the sediment for the whole sampling area. Most of the heavy metals were below the maximum allowable levels set by the WHO, FEPA and USEPA, except Zinc which mean concentration of 0.099 +/- 0.00404 microg/g was above the recommended limit of 0.0766 microg/g of USEPA in the sediment at Ikom. This implies that the waste assimilation capacity of the river is high, a phenomenon that could be ascribed to dilution, sedimentation and continuous water exchange. This is an indication that an urban and industrial waste discharged into the Cross River has a significant effect on the ecological balance of the river. Thus fish species from the Cross River harvested are safe for human consumption.

A new species of Aspidoras Ihering (Siluriformes: Callichthyidae: Corydoradinae) from the Rio Xingu Basin, Pará, Brazil.

PubMed

Leão, Manuela D V; Britto, Marcelo R; Wosiacki, Wolmar B

2015-07-21

A new species of Aspidoras is described from an unnamed stream in the Rio Xingu Basin, Castelo de Sonhos municipality, Pará State, representing the northernmost record of the genus along the edge of the Brazilian Shield in the Amazon Basin. Aspidoras marianae is easily distinguished from all congeners in having minute odontode-bearing platelets scattered over the surface of the snout region, minute platelets between the parieto-supraoccipital process and the nuchal plate, and other shared features related to color pattern, morphometrics, meristics and morphological data. Comments about exclusive and shared features are presented.

The Bunocephalus coracoideus Species Complex (Siluriformes, Aspredinidae). Signs of a Speciation Process through Chromosomal, Genetic and Ecological Diversity

PubMed Central

Ferreira, Milena; Garcia, Caroline; Matoso, Daniele A.; de Jesus, Isac S.; Cioffi, Marcelo de B.; Bertollo, Luiz A. C.; Zuanon, Jansen; Feldberg, Eliana

2017-01-01

Bunocephalus is the most species-rich Aspredinidae genus, corresponding to a monophyletic clade with 13 valid species. However, many species have their classification put in question. Here, we analyzed individuals from four Amazonian populations of Bunocephalus coracoideus by cytogenetic and molecular procedures. The geographic distribution, genetic distances and karyotype data indicate that each population represents an Evolutionary Significant Unit (ESU). Cytogenetic markers showed distinct 2n and karyotype formulas, as well as different numbers and locations of the rDNA sites among ESUs. One of such populations (ESU-D) highlighted an extensive polymorphic condition, with several cytotypes probably due to chromosomal rearrangements and meiotic non-disjunctions. This resulted in several aneuploid karyotypes, which was also supported by the mapping of telomeric sequences. Phylograms based on Maximum Likelihood (ML) and Neighbor Joining (NJ) analyses grouped each ESU on particular highly supported clades, with the estimation of evolutionary divergence indicating values being higher than 3.8–12.3% among them. Our study reveals a huge degree of chromosomal and genetic diversity in B. coracoideus and highly points to the existence of four ESUs in allopatric and sympatric speciation processes. In fact, the high divergences found among the ESUs allowed us to delimitate lineages with taxonomic uncertainties in this nominal species. PMID:28983316

Morphological analysis of Trichomycterus areolatus Valenciennes, 1846 from southern Chilean rivers using a truss-based system (Siluriformes, Trichomycteridae)

PubMed Central

Colihueque, Nelson; Corrales, Olga; Yáñez, Miguel

2017-01-01

Abstract Trichomycterus areolatus Valenciennes, 1846 is a small endemic catfish inhabiting the Andean river basins of Chile. In this study, the morphological variability of three T. areolatus populations, collected in two river basins from southern Chile, was assessed with multivariate analyses, including principal component analysis (PCA) and discriminant function analysis (DFA). It is hypothesized that populations must segregate morphologically from each other based on the river basin that they were sampled from, since each basin presents relatively particular hydrological characteristics. Significant morphological differences among the three populations were found with PCA (ANOSIM test, r = 0.552, p < 0.0001) and DFA (Wilks’s λ = 0.036, p < 0.01). PCA accounted for a total variation of 56.16% by the first two principal components. The first Principal Component (PC1) and PC2 explained 34.72 and 21.44% of the total variation, respectively. The scatter-plot of the first two discriminant functions (DF1 on DF2) also validated the existence of three different populations. In group classification using DFA, 93.3% of the specimens were correctly-classified into their original populations. Of the total of 22 transformed truss measurements, 17 exhibited highly significant (p < 0.01) differences among populations. The data support the existence of T. areolatus morphological variation across different rivers in southern Chile, likely reflecting the geographic isolation underlying population structure of the species. PMID:29134012

A new species of Trichodina Ehrenberg, 1830 (Ciliophora: Trichodinidae) infecting farmed Clarias gariepinus (Burchell) (Siluriformes: Clariidae) in Cuba.

PubMed

León, Fernando Lucas Prats; Pérez, Mercedes Martínez

2017-11-01

A new species of Trichodina Ehrenberg, 1830 collected from the skin and fins of farmed North African catfish Clarias gariepinus (Burchell) fingerlings, is described. The new species can be distinguished from other trichodinids by the characteristics of the adhesive disc, especially by the great number of denticles. Trichodina merciae n. sp. is morphologically similar to T. renicola (Mueller, 1931) and T. marplatensis Martorelli, Marcotegui & Alda, 2008, in the number of denticles, but differs in the morphometric data, denticle morphology, environment and location. Trichodina merciae n. sp. has broad sickle-shaped blades and thin, straight rays, while T. marplatensis has broad club-shaped blades and wide S-shaped rays. Besides, denticle length, blade length, ray length, width of central part and denticle span of the new species are greater than T. marplatensis. However, the diameter of denticle ring and the diameter of the central area in T. marplatensis is larger than the ones in T. merciae n. sp. This is the first record of freshwater ectoparasite trichodinid with an average number of denticles greater than 50.

The Bunocephalus coracoideus Species Complex (Siluriformes, Aspredinidae). Signs of a Speciation Process through Chromosomal, Genetic and Ecological Diversity.

PubMed

Ferreira, Milena; Garcia, Caroline; Matoso, Daniele A; de Jesus, Isac S; Cioffi, Marcelo de B; Bertollo, Luiz A C; Zuanon, Jansen; Feldberg, Eliana

2017-01-01

Bunocephalus is the most species-rich Aspredinidae genus, corresponding to a monophyletic clade with 13 valid species. However, many species have their classification put in question. Here, we analyzed individuals from four Amazonian populations of Bunocephalus coracoideus by cytogenetic and molecular procedures. The geographic distribution, genetic distances and karyotype data indicate that each population represents an Evolutionary Significant Unit (ESU). Cytogenetic markers showed distinct 2n and karyotype formulas, as well as different numbers and locations of the rDNA sites among ESUs. One of such populations (ESU-D) highlighted an extensive polymorphic condition, with several cytotypes probably due to chromosomal rearrangements and meiotic non-disjunctions. This resulted in several aneuploid karyotypes, which was also supported by the mapping of telomeric sequences. Phylograms based on Maximum Likelihood (ML) and Neighbor Joining (NJ) analyses grouped each ESU on particular highly supported clades, with the estimation of evolutionary divergence indicating values being higher than 3.8-12.3% among them. Our study reveals a huge degree of chromosomal and genetic diversity in B. coracoideus and highly points to the existence of four ESUs in allopatric and sympatric speciation processes. In fact, the high divergences found among the ESUs allowed us to delimitate lineages with taxonomic uncertainties in this nominal species.

Morphological analysis of Trichomycterus areolatus Valenciennes, 1846 from southern Chilean rivers using a truss-based system (Siluriformes, Trichomycteridae).

PubMed

Colihueque, Nelson; Corrales, Olga; Yáñez, Miguel

2017-01-01

Trichomycterus areolatus Valenciennes, 1846 is a small endemic catfish inhabiting the Andean river basins of Chile. In this study, the morphological variability of three T. areolatus populations, collected in two river basins from southern Chile, was assessed with multivariate analyses, including principal component analysis (PCA) and discriminant function analysis (DFA). It is hypothesized that populations must segregate morphologically from each other based on the river basin that they were sampled from, since each basin presents relatively particular hydrological characteristics. Significant morphological differences among the three populations were found with PCA (ANOSIM test, r = 0.552, p < 0.0001) and DFA (Wilks's λ = 0.036, p < 0.01). PCA accounted for a total variation of 56.16% by the first two principal components. The first Principal Component (PC1) and PC2 explained 34.72 and 21.44% of the total variation, respectively. The scatter-plot of the first two discriminant functions (DF1 on DF2) also validated the existence of three different populations. In group classification using DFA, 93.3% of the specimens were correctly-classified into their original populations. Of the total of 22 transformed truss measurements, 17 exhibited highly significant ( p < 0.01) differences among populations. The data support the existence of T. areolatus morphological variation across different rivers in southern Chile, likely reflecting the geographic isolation underlying population structure of the species.

Taxonomic revision of the South American catfish genus Ageneiosus (Siluriformes: Auchenipteridae) with the description of four new species

USGS Publications Warehouse

Ribeiro, Frank R.V.; Rapp Py-Daniel, Lúcia H.; Walsh, Stephen J.

2017-01-01

The catfish genus Ageneiosus in the exclusively Neotropical family Auchenipteridae is revised. Species of Ageneiosus are widely distributed in all major South American continental drainages except the São Francisco River basin and small rivers along the Brazilian east coast. The taxonomic revision was based on examination of available type specimens, additional museum material and comparisons of original descriptions. A suite of morphometric, meristic and qualitative characters of internal and external anatomy were used to diagnose valid species and determine synonyms. Thirteen valid species are recognized in the genus Ageneiosus, some of which are widely distributed across South America. Ageneiosus pardalis is the only trans-Andean species in the genus. Ageneiosus polystictus and Ageneiosus uranophthalmus are more widely distributed than previously reported. Ageneiosus marmoratus is a junior synonym of Ageneiosus inermis. Ageneiosus dentatus is a valid species and its name is removed from the synonymy of Ageneiosus ucayalensis. Four new species are described: Ageneiosus akamai, Ageneiosus apiaka, Ageneiosus intrusus and Ageneiosus lineatus, all from the Amazon River basin. A dichotomous key for all 13 valid species of Ageneiosus species is provided.

Catfish science: Status and trends in the 21st century

USGS Publications Warehouse

Kwak, Thomas J.; Porath, Mark T.; Michaletz, Paul H.; Travnichek, Vincent H.

2011-01-01

Catfish science, the study of the fish order Siluriformes, is a diverse and expanding field in terms of advances and breadth of topics. We compiled literature from primary fisheries journals as an index of interest and advances in catfish science to examine temporal trends in the field. The number of catfish scientific publications varied over the past century with strong peaks during 1975–1979 and 2005–2010, which may be the result of interactive scientific and societal influences. Catfish biology was the predominant publication topic until the late 1990s, when ecology, techniques, and management publications became more prevalent. Articles on catfish ecology were most numerous in both the first and second international catfish symposia, but publications on techniques and conservation were more numerous in the second catfish symposium than the first. We summarize the state of knowledge, recent advances, and areas for future attention among topics in catfish science, including sampling and aging techniques, population dynamics, ecology, fisheries management, species diversity, nonnative catfish, and human dimensions, with an emphasis on the gains in this second symposium. Areas that we expect to be pursued in the future are development of new techniques and validation of existing methods; expansion of research to less-studied catfish species; broadening temporal, spatial, and organizational scales; interdisciplinary approaches; and research on societal views and constituent demands. Meeting these challenges will require scientists to span beyond their professional comfort zones to effectively reach higher standards. We look forward to the coming decade and the many advances in the conservation, ecology, and management of catfish that will be shared.

The cranial cartilages of teleosts and their classification.

PubMed

Benjamin, M

1990-04-01

The structure and distribution of cartilages has been studied in 45 species from 24 families. The resulting data have been used as a basis for establishing a new classification. A cartilage is regarded as 'cell-rich' if its cells or their lacunae occupy more than half of the tissue volume. Five classes of cell-rich cartilage are recognised (a) hyaline-cell cartilage (common in the lips of bottom-dwelling cyprinids) and its subtypes fibro/hyaline-cell cartilage, elastic/hyaline-cell cartilage and lipo/hyaline-cell cartilage, (b) Schaffer's Zellknorpel, typified by the cartilage in the gill filaments of most teleosts examined, (c) elastic/cell-rich cartilage, such as that which supports the barbels and oral valves of catfish, e.g. Corydoras metae, (d) fibro/cell-rich cartilage, as in the submaxillary meniscus of Sphaerichthys osphromenoides, (e) cell-rich hyaline and (f) matrix-rich hyaline cartilage--both of which are common in the neurocranium and gill arches of most teleosts. The range of cartilages seen, and the predominant cartilage type, is recorded for each species and a list is provided of the tissues that most typify different organs or regions of the head. As a preliminary pointer to developmental relationships between the cartilages, note was taken of gradual transitions between one cartilage and another. It is suggested that hyaline-cell cartilage occupies a key position in teleosts as the most labile of the supporting tissues and is highly characteristic of Cypriniformes. The cartilage that best resembles mammalian hyaline cartilage (matrix-rich hyaline cartilage) has a very conservative distribution in different skeletal elements and the least number of associations with other tissues. It is well represented in Siluriformes.

A new monozoic tapeworm, Lobulovarium longiovatum n. g., n. sp. (Cestoda: Caryophyllidea), from barbs Puntius spp. (Teleostei: Cyprinidae) in the Indomalayan region.

PubMed

Oros, Mikuláš; Ash, Anirban; Brabec, Jan; Kar, Pradip Kumar; Scholz, Tomáš

2012-09-01

A new caryophyllidean cestode is described from barbs Puntius spp. (Cypriniformes: Cyprinidae), with P. sophore (Hamilton) as its type-host, in the Ganges and Brahmaputra river basins in India and Bangladesh, and a new genus, Lobulovarium n. g., is proposed to accommodate it. The genus belongs to the Lytocestidae because its vitelline follicles are situated in the cortex. It is typified by: (i) a peculiar ovary, which is roughly H-shaped, but with asymmetrical, irregular lobes on its ventral and dorsal sides; (ii) an extensive vitellarium formed by numerous vitelline follicles scattered throughout the cortex; (iii) a long, conical postovarian part of the body with numerous vitelline follicles; (iv) a broadly digitate scolex with a slightly protrusible central cone; (v) a single gonopore (male and female genital ducts open via a single pore and a common genital atrium is absent); and (vi) a small number of testes (< 60). Molecular data (partial sequences of the lsrDNA) indicate that Lobulovarium longiovatum n. sp. belongs among the most basal caryophyllidean cestodes, being unrelated to species from siluriform catfishes in the Indomalayan region. Paracaryophyllaeus osteobramensis (Gupta & Sinha, 1984) Hafeezullah, 1993 (syn. Pliovitellaria osteobramensis Gupta & Sinha, 1984) from another cyprinid fish, Osteobrama cotio (Hamilton), in Uttar Pradesh, India, is tentatively transferred to Lobulovarium as L. osteobramense (Gupta & Sinha, 1984) n. comb. It differs from L. longiovatum by having much smaller eggs (length <50 μm versus >90 μm in L. longiovatum), which are spherical (length/width ratio 1:1 versus 2.5-3:1 in the new species), and the presence of vitelline follicles alongside the ovarian lobes (almost completely absent in L. longiovatum).

Prosthenystera oonastica n. sp. (Digenea: Callodistomidae) from ictalurid catfishes in southeastern United States and molecular evidence differentiating species in the genus across Americas.

PubMed

Tkach, Vasyl V; Curran, Stephen S

2015-01-01

Prosthenhystera oonastica n. sp. is described as a cryptic species from the gall bladder of three ictalurid catfishes, Ictalurus punctatus (Rafinesque), Ictalurus furcatus (Valenciennes), and Pylodictis olivaris (Rafinesque), in rivers in the southeastern United States. The species was originally named by Wilmer A. Rogers in 1979 but never formally described. Material used for the description consists of two specimens of Roger's original material and ten new specimens. We found no significant morphological features that are useful for discriminating between the new species and its closest relative Prosthenhystera obesa (Diesing, 1850) Travassos, 1922 that occurs in the gall bladders of freshwater characiform, perciform and siluriform fishes, ranging from South America to southern Mexico. However, we found substantial differences in the large subunit ribosomal DNA (partial 28S rRNA gene) between the two species justifying the naming of the new species. Prosthenhystera oonastica n. sp. is readily differentiated from Prosthenhystera caballeroi Jiménez-Guzmán, 1973 that occurs in the gall bladders of characid fishes in Central America and Mexico, by having a relatively straight or bent rather than highly convoluted oesophagus, a relatively smaller ovary, smaller and less coalesced vitelline follicles, narrower caeca and smaller eggs. Comparison of ribosomal DNA (partial ITS1, 5.8S, ITS2, and partial 28S gene) between P. oonastica n. sp. and P. caballeroi revealed large differences between the two species. Phylogenetic analysis based on partial 28S rRNA gene sequences from the three studied species of Prosthenhystera Travassos, 1922 and related digenean taxa revealed a closer relationship between P. oonastica n. sp. and P. obesa than either has had with P. caballeroi.

Effects of Temperature on Auditory Sensitivity in Eurythermal Fishes: Common Carp Cyprinus carpio (Family Cyprinidae) versus Wels Catfish Silurus glanis (Family Siluridae)

PubMed Central

Maiditsch, Isabelle Pia; Ladich, Friedrich

2014-01-01

Background In ectothermal animals such as fish, -temperature affects physiological and metabolic processes. This includes sensory organs such as the auditory system. The reported effects of temperature on hearing in eurythermal otophysines are contradictory. We therefore investigated the effect on the auditory system in species representing two different orders. Methodology/Principal Findings Hearing sensitivity was determined using the auditory evoked potentials (AEP) recording technique. Auditory sensitivity and latency in response to clicks were measured in the common carp Cyprinus carpio (order Cypriniformes) and the Wels catfish Silurus glanis (order Siluriformes) after acclimating fish for at least three weeks to two different water temperatures (15°C, 25°C and again 15°C). Hearing sensitivity increased with temperature in both species. Best hearing was detected between 0.3 and 1 kHz at both temperatures. The maximum increase occurred at 0.8 kHz (7.8 dB) in C. carpio and at 0.5 kHz (10.3 dB) in S. glanis. The improvement differed between species and was in particular more pronounced in the catfish at 4 kHz. The latency in response to single clicks was measured from the onset of the sound stimulus to the most constant positive peak of the AEP. The latency decreased at the higher temperature in both species by 0.37 ms on average. Conclusions/Significance The current study shows that higher temperature improves hearing (lower thresholds, shorter latencies) in eurythermal species from different orders of otophysines. Differences in threshold shifts between eurythermal species seem to reflect differences in absolute sensitivity at higher frequencies and they furthermore indicate differences to stenothermal (tropical) species. PMID:25255456

Understanding morphological variability in a taxonomic context in Chilean diplomystids (Teleostei: Siluriformes), including the description of a new species

PubMed Central

2017-01-01

Following study of the external morphology and its unmatched variability throughout ontogeny and a re-examination of selected morphological characters based on many specimens of diplomystids from Central and South Chile, we revised and emended previous specific diagnoses and consider Diplomystes chilensis, D. nahuelbutaensis, D. camposensis, and Olivaichthys viedmensis (Baker River) to be valid species. Another group, previously identified as Diplomystes sp., D. spec., D. aff. chilensis, and D. cf. chilensis inhabiting rivers between Rapel and Itata Basins is given a new specific name (Diplomystes incognitus) and is diagnosed. An identification key to the Chilean species, including the new species, is presented. All specific diagnoses are based on external morphological characters, such as aspects of the skin, neuromast lines, and main lateral line, and position of the anus and urogenital pore, as well as certain osteological characters to facilitate the identification of these species that previously was based on many internal characters. Diplomystids below 150 mm standard length (SL) share a similar external morphology and body proportions that make identification difficult; however, specimens over 150 mm SL can be diagnosed by the position of the urogenital pore and anus, and a combination of external and internal morphological characters. According to current knowledge, diplomystid species have an allopatric distribution with each species apparently endemic to particular basins in continental Chile and one species (O. viedmensis) known only from one river in the Chilean Patagonia, but distributed extensively in southern Argentina. PMID:28224053

A new species of Pseudocrepidobothrium (Cestoda: Proteocephalidea) from Pseudoplatystoma reticulatum (Pisces: Siluriformes) in the Paraná River basin (Argentina).

PubMed

Arredondo, Nathalia J; De Pertierra, Alicia A Gil; De Chambrier, Alain

2014-10-01

This study describes the proteocephalidean tapeworm Pseudocrepidobothrium chanaorum sp. n. (Proteocephalidae: Proteocephalinae), which was found in the intestine of Pseudoplatystoma reticulatum (Eigenmann et Eigenmann) from the Colastiné River, a tributary of the Paraná River. The new species differs from the two other species of the genus, P. eirasi (Rego et de Chambrier, 1995) and P. ludovici Ruedi et de Chambrier, 2012, parasites of Phractocephalus hemioliopterus (Bloch et Schneider) from the Amazon River in Brazil, in having fewer proglottides (4-8 without ventral appendages vs 7-12 with ventral appendages and 20-36 without ventral appendages, respectively), a smaller scolex (350-450 μm wide vs 495-990 μm and 515-1020 μm wide, respectively), in the total number of testes (21-25 vs 21-51 and 37-79, respectively), a cirrus-sac usually directed anteriorly if the vagina is posterior to the cirrus-sac vs transversely situated in the known species. The study of the tegumental surface of Pseudocrepidobothrium spp. revealed the presence of four types of microtriches: papilliform, acicular and capilliform filitriches, and gladiate spinitriches. The three species have a similar microthrix pattern, with minor differences on the immature proglottis surface. Pseudocrepidobothrium chanaorum sp. n. is the ninth proteocephalid reported from P. reticulatum.

An integrative framework to reevaluate the Neotropical catfish genus Guyanancistrus (Siluriformes: Loricariidae) with particular emphasis on the Guyanancistrus brevispinis complex.

PubMed

Fisch-Muller, Sonia; Mol, Jan H A; Covain, Raphaël

2018-01-01

Characterizing and naming species becomes more and more challenging due to the increasing difficulty of accurately delineating specific bounderies. In this context, integrative taxonomy aims to delimit taxonomic units by leveraging the complementarity of multiple data sources (geography, morphology, genetics, etc.). However, while the theoretical framework of integrative taxonomy has been explicitly stated, methods for the simultaneous analysis of multiple data sets are poorly developed and in many cases different information sources are still explored successively. Multi-table methods developed in the field of community ecology provide such an intregrative framework. In particular, multiple co-inertia analysis is flexible enough to allow the integration of morphological, distributional, and genetic data in the same analysis. We have applied this powerfull approach to delimit species boundaries in a group of poorly differentiated catfishes belonging to the genus Guyanancistrus from the Guianas region of northeastern South America. Because the species G. brevispinis has been claimed to be a species complex consisting of five species, particular attention was paid to taxon. Separate analyses indicated the presence of eight distinct species of Guyanancistrus, including five new species and one new genus. However, none of the preliminary analyses revealed different lineages within G. brevispinis, and the multi-table analysis revealed three intraspecific lineages. After taxonomic clarifications and description of the new genus, species and subspecies, a reappraisal of the biogeography of Guyanancistrus members was performed. This analysis revealed three distinct dispersals from the Upper reaches of Amazonian tributaries toward coastal rivers of the Eastern Guianas Ecoregion. The central role played by the Maroni River, as gateway from the Amazon basin, was confirmed. The Maroni River was also found to be a center of speciation for Guyanancistrus (with three species and two subspecies), as well as a source of dispersal of G. brevispinis toward the other main basins of the Eastern Guianas.

An integrative framework to reevaluate the Neotropical catfish genus Guyanancistrus (Siluriformes: Loricariidae) with particular emphasis on the Guyanancistrus brevispinis complex

PubMed Central

Fisch-Muller, Sonia; Mol, Jan H. A.

2018-01-01

Characterizing and naming species becomes more and more challenging due to the increasing difficulty of accurately delineating specific bounderies. In this context, integrative taxonomy aims to delimit taxonomic units by leveraging the complementarity of multiple data sources (geography, morphology, genetics, etc.). However, while the theoretical framework of integrative taxonomy has been explicitly stated, methods for the simultaneous analysis of multiple data sets are poorly developed and in many cases different information sources are still explored successively. Multi-table methods developed in the field of community ecology provide such an intregrative framework. In particular, multiple co-inertia analysis is flexible enough to allow the integration of morphological, distributional, and genetic data in the same analysis. We have applied this powerfull approach to delimit species boundaries in a group of poorly differentiated catfishes belonging to the genus Guyanancistrus from the Guianas region of northeastern South America. Because the species G. brevispinis has been claimed to be a species complex consisting of five species, particular attention was paid to taxon. Separate analyses indicated the presence of eight distinct species of Guyanancistrus, including five new species and one new genus. However, none of the preliminary analyses revealed different lineages within G. brevispinis, and the multi-table analysis revealed three intraspecific lineages. After taxonomic clarifications and description of the new genus, species and subspecies, a reappraisal of the biogeography of Guyanancistrus members was performed. This analysis revealed three distinct dispersals from the Upper reaches of Amazonian tributaries toward coastal rivers of the Eastern Guianas Ecoregion. The central role played by the Maroni River, as gateway from the Amazon basin, was confirmed. The Maroni River was also found to be a center of speciation for Guyanancistrus (with three species and two subspecies), as well as a source of dispersal of G. brevispinis toward the other main basins of the Eastern Guianas. PMID:29298344

Serous goblet cells: the protein secreting cells in the oral cavity of a catfish, Rita rita (Hamilton, 1822) (Bagridae, Siluriformes).

PubMed

Yashpal, Madhu; Mittal, Ajay Kumar

2014-02-01

Serous goblet cells in the oral epithelium of Rita rita are characterized by the presence of distinct eosinophilic granules occupying large parts of the cytoplasm. In R. rita, a range of histochemical results reveal that these cells are involved in proteinaceous secretions, and thus likely contribute to various functions analogous to those of mammalian saliva. The secretions of these cells have also been associated with specific functions and are discussed in relation to their physiological importance with special reference to their roles in lubrication, alteration in viscosity, various functions of mucus such as handling, maneuvering and driving of food items toward the esophagus, maintaining taste sensitivity and protection of the oral epithelium. In addition, the serous goblet cells may also be considered as the primary defensive cell of the oral epithelium of R. rita. The results significantly add to very limited set of literature on the serous goblet cells and provide noteworthy information on the mucous secretions in the oral cavity of fish. Copyright © 2013 Elsevier Ltd. All rights reserved.

Ritacestus gen. n. (Cestoda: Proteocephalidea) and redescription of R. ritaii comb. n., a parasite of Rita rita (Siluriformes) in India.

PubMed

de Chambrier, Alain; Scholz, Tomás; Ash, Anirban; Kar, Pradip Kumar

2011-11-01

A new genus, Ritacestus, is proposed to accommodate Ritacestus ritaii (Verma, 1926) comb. n. (syn. Proteocephalus ritaii), a parasite of the catfish Rita rita (Hamilton) in India. The new genus, which is placed in the Gangesiinae, is characterized by (i) a small, subspherical scolex formed by four large lobes separated from one another by longitudinal grooves, with a large, widely oval to pyriform rostellum-like apical organ, larger than suckers and possessing an apical hemispherical depression; (ii) paramuscular and cortical position of some vitelline follicles (most follicles are situated medullary); (iii) ventral and dorsal bands of vitelline follicles usually uninterrupted ventral to terminal genitalia and reaching to the posterior margin of proglottides; (iv) the vagina always anterior to the cirrus-sac; (v) a large size of the body (length up to 51 cm); and (vi) development of the uterus of type 2. In its morphology, especially shape of the scolex and apical organ, and paramuscular and cortical position of some vitelline follicles, Ritacestus resembles Postgangesia Akhmerov, 1969, but differs in the presence of a genital atrium (both genital pores of Postgangesia are separate), the anterior position of the vagina (almost always posterior in the latter genus), position of vitelline follicles in cross sections (dorsal and ventral bands in Ritacestus versus only a lateral band in the latter genus), and dorsal excretory canals indistinguishable in mature and gravid proglottides of R. ritaii (well developed in Postgangesia spp.). The type and only species of the genus, R. ritaii, is redescribed on the basis of new material from the type host from the Ganges River basin in India and its neotype is designated.

Genetic structure and historical diversification of catfish Brachyplatystoma platynemum (Siluriformes: Pimelodidae) in the Amazon basin with implications for its conservation.

PubMed

Ochoa, Luz Eneida; Pereira, Luiz Henrique G; Costa-Silva, Guilherme Jose; Roxo, Fábio F; Batista, Jacqueline S; Formiga, Kyara; Foresti, Fausto; Oliveira, Claudio

2015-05-01

Brachyplatystoma platynemum is a catfish species widely distributed in the Amazon basin. Despite being considered of little commercial interest, the decline in other fish populations has contributed to the increase in the catches of this species. The structure, population genetic variability, and evolutionary process that have driven the diversification of this species are presently unknown. Considering that, in order to better understand the genetic structure of this species, we analyzed individuals from seven locations of the Amazon basin using eight molecular markers: control region and cytochrome b mtDNA sequences, and a set of six nuclear microsatellite loci. The results show high levels of haplotype diversity and point to the occurrence of two structured populations (Amazon River and the Madeira River) with high values for F ST. Divergence time estimates based on mtDNA indicated that these populations diverged about 1.0 Mya (0.2-2.5 Mya 95% HPD) using cytochrome b and 1.4 Mya (0.2-2.7 Mya 95% HPD) using control region. During that time, the influence of climate changes and hydrological events such as sea level oscillations and drainage isolation as a result of geological processes in the Pleistocene may have contributed to the current structure of B. platynemum populations, as well as of differences in water chemistry in Madeira River. The strong genetic structure and the time of genetic divergence estimated for the groups may indicate the existence of strong structure populations of B. platynemum in the Amazon basin.

Cytogenetics of the Porthole Shovelnose Catfish, Hemisorubim platyrhynchos (Valenciennes, 1840) (Siluriformes, Pimelodidae), a widespread species in South American rivers

PubMed Central

Swarça, Ana Cláudia; Sanchez, Sebastian; Dias, Ana Lucia; Fenocchio, Alberto Sergio

2013-01-01

Abstract Hemisorubim platyrhynchos is a medium- to large-sized pimelodid catfish distributed along several river basins of the Neotropical Region, noteworthy for representing an important fishery source. In this work, Hemisorubim platyrhynchos from three isolated populations were cytogenetically analyzed. The karyotype shows a diploid number of 2n=56 chromosomes comprising 22m, 16sm, 10st, 8a (FN=104). NORs detected by AgNO3 were located in the terminal regions of the short arm of a st chromosome pair, as confirmed by CMA3 and FISH using an 18S rDNA probe. C-banding revealed a small amount of heterochromatin in chromosomes, including the NORs, and one biarmed pair that showed conspicuous positive bands on both arms. This fact was also evidenced when using other banding techniques, such as RE (AluI), and indicates that this pair constitutes a species-specific cytogenetic marker. PMID:24260693

Morphological and ultrastructural aspects of Myxobolus niger n. sp. (Myxozoa) gill parasite of Corydoras melini (Siluriformes: Callichthyidae) from Brazilian Amazon.

PubMed

Mathews, Patrick D; Maia, Antônio A M; Adriano, Edson A

2016-06-01

Myxobolus niger n. sp. (Myxozoa) is described in the connective tissue of the serosa layer of the gill arch of Corydoras melini (Callichthyidae) captured from the Negro River, Amazonas State, Brazil. The prevalence of the parasite was 20% and the range intensity was 1-2 cysts per fish. The plasmodia were white and spherical to ellipsoidal, measuring 175 μm in diameter and were surrounded by a well-defined capsule of host connective tissue, with distinct delicate and interlaced collagen fibers. The myxospores body was ellipsoidal in frontal view and biconvex in sutural view. Spore dimensions were 11.3 ± 0.4 μm in length, 6.8 ± 0.2 μm in width and 4.1 ± 0.2 μm in thickness. The valves were symmetrical and smooth. The two polar capsules were elongated as pyriform and equal in size, measure 5.0 ± 0.3 μm in length and 2.0 ± 0.1 μm in width. The polar capsule had six to seven polar filament turns. Some aberrant spores were round in shape and had three polar capsules. The sporoplasm was binucleated and contained moderated number of sporoplasmosomes. The development of the plasmodia was asynchronic, with mature and immature spores. The plasmodium had moderated pynocitic channels. There were no projections, no invaginations and no microvilli in the plasmodial wall. This study is the first description of Myxobolus species in the fish of the Callichthyidae family. Copyright © 2016 Elsevier B.V. All rights reserved.

A new long-snouted species of Corydoras Lacépède, 1803 (Siluriformes: Callichthyidae) from the rio Madeira basin.

PubMed

Tencatt, Luiz Fernando Caserta; Ohara, Willian Massaharu

2016-07-28

A new species of Corydoras is described from the rio Aripuanã, rio Madeira basin, Mato Grosso State, Brazil. The new species can be distinguished from its congeners by the presence of the following features: long mesethmoid, with anterior tip well developed, conspicuously larger than 50% of bone length; posterior margin of dorsal-fin spine with serrations directed towards tip of spine; one to two longitudinal black stripes on flanks; absence of a black blotch across the eyes (mask); absence of a large black blotch on dorsal fin; and transversal black bars on caudal fin. Comments on endemism in interfluvial region between Madeira and Tapajós rivers are briefly discussed.

Genetic structure and historical diversification of catfish Brachyplatystoma platynemum (Siluriformes: Pimelodidae) in the Amazon basin with implications for its conservation

PubMed Central

Ochoa, Luz Eneida; Pereira, Luiz Henrique G; Costa-Silva, Guilherme Jose; Roxo, Fábio F; Batista, Jacqueline S; Formiga, Kyara; Foresti, Fausto; Oliveira, Claudio

2015-01-01

Brachyplatystoma platynemum is a catfish species widely distributed in the Amazon basin. Despite being considered of little commercial interest, the decline in other fish populations has contributed to the increase in the catches of this species. The structure, population genetic variability, and evolutionary process that have driven the diversification of this species are presently unknown. Considering that, in order to better understand the genetic structure of this species, we analyzed individuals from seven locations of the Amazon basin using eight molecular markers: control region and cytochrome b mtDNA sequences, and a set of six nuclear microsatellite loci. The results show high levels of haplotype diversity and point to the occurrence of two structured populations (Amazon River and the Madeira River) with high values for FST. Divergence time estimates based on mtDNA indicated that these populations diverged about 1.0 Mya (0.2–2.5 Mya 95% HPD) using cytochrome b and 1.4 Mya (0.2–2.7 Mya 95% HPD) using control region. During that time, the influence of climate changes and hydrological events such as sea level oscillations and drainage isolation as a result of geological processes in the Pleistocene may have contributed to the current structure of B. platynemum populations, as well as of differences in water chemistry in Madeira River. The strong genetic structure and the time of genetic divergence estimated for the groups may indicate the existence of strong structure populations of B. platynemum in the Amazon basin. PMID:26045952

Proteocephalus brooksi n. sp. (Cestoda:Proteocephalidae) in the neotropical freshwater fish Rhamdia guatemalensis (Siluriformes: Pimelodidae) from Lake Catemaco, Veracruz, Mexico.

PubMed

García-Prieto, L; Rodríguez, L M; Pérez-Ponce de León, G

1996-12-01

Proteocephalus brooksi n. sp. is described from the neotropical pimelodid fish Rhamdia guatemalensis from Lake Catemaco, Veracruz, México. The new species is characterized by the "paramuscular" position of vitellaria, the cortical origin of uterine stem with development of medullar lateral branches, the alternated position of vagina (anteriorly and posteriorly to cirrus sac), and the absence of apical organ and vaginal sphincter. Proteocephalus brooksi most closely resembles Nomimoscolex matogrossensis from which it differs in a series of characters. The probable paraphyletic nature of both Proteocephalus and Nomimoscolex and the convergent evolution of the "paramuscular" location of vitellaria among proteocephalideans are suggested, and the need for a phylogenetic analysis of the group is emphasized. The new species is assigned to Proteocephalus pending such an analysis.

Karyotypic diversity and evolutionary trends in the Neotropical catfish genus Hypostomus Lacépède, 1803 (Teleostei, Siluriformes, Loricariidae)

PubMed Central

Alves, Anderson Luis; de Borba, Rafael Splendore; Oliveira, Claudio; Mauro Nirchio; Granado, Angel; Foresti, Fausto

2012-01-01

Abstract The family Loricariidae with 813 nominal species is one of the largest fish families of the world. Hypostominae, its more complex subfamily, was recently divided into five tribes. The tribe Hypostomini is composed of a single genus, Hypostomus Lacépède, 1803, which exhibits the largest karyotypic diversity in the family Loricariidae. With the main objective of contributing to a better understanding of the relationship and the patterns of evolution among the karyotypes of Hypostomus species, cytogenetic studies were conducted in six species of the genus from Brazil and Venezuela. The results show a great chromosome variety with diploid numbers ranging from 2n=68 to 2n=76, with a clear predominance of acrocentric chromosomes. The Ag-NORs are located in terminal position in all species analyzed. Three species have single Ag-NORs (Hypostomus albopunctatus (Regan, 1908), Hypostomus prope plecostomus (Linnaeus, 1758), and Hypostomus prope paulinus (Ihering, 1905)) and three have multiple Ag-NORs (Hypostomus ancistroides (Ihering, 1911), Hypostomus prope iheringi (Regan, 1908), and Hypostomus strigaticeps (Regan, 1908)). In the process of karyotype evolution of the group, the main type of chromosome rearrangements was possibly centric fissions, which may have been facilitated by the putative tetraploid origin of Hypostomus species. The relationship between the karyotype changes and the evolution in the genus is discussed. PMID:24260683

Multilocus molecular phylogeny of the ornamental wood-eating catfishes (Siluriformes, Loricariidae, Panaqolus and Panaque) reveals undescribed diversity and parapatric clades.

PubMed

Lujan, Nathan K; Cramer, Christian A; Covain, Raphael; Fisch-Muller, Sonia; López-Fernández, Hernán

2017-04-01

Approximately two-dozen species in three genera of the Neotropical suckermouth armored catfish family Loricariidae are the only described fishes known to specialize on diets consisting largely of wood. We conducted a molecular phylogenetic analysis of 10 described species and 14 undescribed species or morphotypes assigned to the wood-eating catfish genus Panaqolus, and four described species and three undescribed species or morphotypes assigned to the distantly related wood-eating catfish genus Panaque. Our analyses included individuals and species from both genera that are broadly distributed throughout tropical South America east of the Andes Mountains and 13 additional genera hypothesized to have also descended from the most recent common ancestor of Panaqolus and Panaque. Bayesian and maximum likelihood analyses of two mitochondrial and three nuclear loci totaling 4293bp confirmed respective monophyly of Panaqolus, exclusive of the putative congener 'Panaqolus' koko, and Panaque. Members of Panaqolus sensu stricto were distributed across three strongly monophyletic clades: a clade of 10 generally darkly colored, lyretail species distributed across western headwaters of the Amazon Basin, a clade of three irregularly and narrowly banded species from the western Orinoco Basin, and a clade of 11 generally brown, broadly banded species that are widely distributed throughout the Amazon Basin. We erect new subgenera for each of these clades and a new genus for the morphologically, biogeographically and ecologically distinct species 'Panaqolus' koko. Our finding that perhaps half of the species-level diversity in the widespread genus Panaqolus remains undescribed illustrates the extent to which total taxonomic diversity of small and philopatric, yet apparently widely distributed, Amazonian fishes may remain underestimated. Ranges for two Panaqolus subgenera and the genus Panaque overlap with the wood-eating genus Cochliodon in central Andean tributaries of the upper Amazon Basin, which appear to be a global epicenter of wood-eating catfish diversity. Copyright © 2016 Elsevier Inc. All rights reserved.

Gonadotropin subunits of the characiform Astyanax altiparanae: Molecular characterization, spatiotemporal expression and their possible role on female reproductive dysfunction in captivity.

PubMed

de Jesus, Lázaro Wender O; Bogerd, Jan; Vieceli, Felipe M; Branco, Giovana S; Camargo, Marília P; Cassel, Mônica; Moreira, Renata G; Yan, Chao Y I; Borella, Maria I

2017-05-15

To better understand the endocrine control of reproduction in Characiformes and the reproductive dysfunctions that commonly occur in migratory fish of this order when kept in captivity, we chose Astyanax altiparanae, which has asynchronous ovarian development and multiple spawning events, as model species. From A. altiparanae pituitary total RNA, we cloned the full-length cDNAs coding for the follicle-stimulating hormone β subunit (fshb), the luteinizing hormone β subunit (lhb), and the common gonadotropin α subunit (gpha). All three sequences showed the highest degree of amino acid identity with other homologous sequences from Siluriformes and Cypriniformes. Real-time, quantitative PCR analysis showed that gpha, fshb and lhb mRNAs were restricted to the pituitary gland. In situ hybridization and immunofluorescence, using specific-developed and characterized polyclonal antibodies, revealed that both gonadotropin β subunits mRNAs/proteins are expressed by distinct populations of gonadotropic cells in the proximal pars distalis. No marked variations for lhb transcripts levels were detected during the reproductive cycle, and 17α,20β-dihydroxy-4-pregnen-3-one plasma levels were also constant, suggesting that the reproductive dysfunction seen in A. altiparanae females in captivity are probably due to a lack of increase of Lh synthesis during spawning season. In contrast, fshb transcripts changed significantly during the reproductive cycle, although estradiol-17β (E 2 ) levels remained constant during the experiment, possibly due to a differential regulation of E 2 synthesis. Taken together, these data demonstrate the putative involvement of gonadotropin signaling on the impairment of the reproductive function in a migratory species when kept in captivity. Future experimental studies must be carried to clarify this hypothesis. All these data open the possibility for further basic and applied studies related to reproduction in this fish model. Copyright © 2016

Novel relationships among ten fish model species revealed based on a phylogenomic analysis using ESTs.

PubMed

Steinke, Dirk; Salzburger, Walter; Meyer, Axel

2006-06-01

The power of comparative phylogenomic analyses also depends on the amount of data that are included in such studies. We used expressed sequence tags (ESTs) from fish model species as a proof of principle approach in order to test the reliability of using ESTs for phylogenetic inference. As expected, the robustness increases with the amount of sequences. Although some progress has been made in the elucidation of the phylogeny of teleosts, relationships among the main lineages of the derived fish (Euteleostei) remain poorly defined and are still debated. We performed a phylogenomic analysis of a set of 42 of orthologous genes from 10 available fish model systems from seven different orders (Salmoniformes, Siluriformes, Cypriniformes, Tetraodontiformes, Cyprinodontiformes, Beloniformes, and Perciformes) of euteleostean fish to estimate divergence times and evolutionary relationships among those lineages. All 10 fish species serve as models for developmental, aquaculture, genomic, and comparative genetic studies. The phylogenetic signal and the strength of the contribution of each of the 42 orthologous genes were estimated with randomly chosen data subsets. Our study revealed a molecular phylogeny of higher-level relationships of derived teleosts, which indicates that the use of multiple genes produces robust phylogenies, a finding that is expected to apply to other phylogenetic issues among distantly related taxa. Our phylogenomic analyses confirm that the euteleostean superorders Ostariophysi and Acanthopterygii are monophyletic and the Protacanthopterygii and Ostariophysi are sister clades. In addition, and contrary to the traditional phylogenetic hypothesis, our analyses determine that killifish (Cyprinodontiformes), medaka (Beloniformes), and cichlids (Perciformes) appear to be more closely related to each other than either of them is to pufferfish (Tetraodontiformes). All 10 lineages split before or during the fragmentation of the supercontinent Pangea in the

Homology of the Fifth Epibranchial and Accessory Elements of the Ceratobranchials among Gnathostomes: Insights from the Development of Ostariophysans

PubMed Central

Carvalho, Murilo; Bockmann, Flávio Alicino; de Carvalho, Marcelo Rodrigues

2013-01-01

Epibranchials are among the main dorsal elements of the gill basket in jawed vertebrates (Gnathostomata). Among extant fishes, chondrichthyans most resemble the putative ancestral condition as all branchial arches possess every serially homologous piece. In osteichthyans, a primitive rod-like epibranchial 5, articulated to ceratobranchial 5, is absent. Instead, epibranchial 5 of many actinopterygians is here identified as an accessory element attached to ceratobranchial 4. Differences in shape and attachment of epibranchial 5 in chondrichthyans and actinopterygians raised suspicions about their homology, prompting us to conduct a detailed study of the morphology and development of the branchial basket of three ostariophysans (Prochilodus argenteus, Characiformes; Lophiosilurus alexandri and Pseudoplatystoma corruscans, Siluriformes). Results were interpreted within a phylogenetic context of major gnathostome lineages. Developmental series strongly suggest that the so-called epibranchial 5 of actinopterygians does not belong to the epal series because it shares the same chondroblastic layer with ceratobranchial 4 and its ontogenetic emergence is considerably late. This neomorphic structure is called accessory element of ceratobranchial 4. Its distribution among gnathostomes indicates it is a teleost synapomorphy, occurring homoplastically in Polypteriformes, whereas the loss of the true epibranchial 5 is an osteichthyan synapomorphy. The origin of the accessory element of ceratobranchial 4 appears to have occurred twice in osteichthyans, but it may have a single origin; in this case, the accessory element of ceratobranchial 4 would represent a remnant of a series of elements distally attached to ceratobranchials 1–4, a condition totally or partially retained in basal actinopterygians. Situations wherein a structure is lost while a similar neomorphic element is present may lead to erroneous homology assessments; these can be avoided by detailed morphological and

Evaluation of the fossil fish-specific diversity in a chadian continental assemblage: Exploration of morphological continuous variation in Synodontis (Ostariophysi, Siluriformes).

PubMed

Pinton, Aurélie; Le Fur, Soizic; Otero, Olga

2016-11-01

In the fossil record, the quantification of continuous morphological variation has become a central issue when dealing with species identification and speciation. In this context, fossil taxa with living representatives hold great promise, because of the potential to characterise patterns of intraspecific morphological variation in extant species prior to any interpretation in the fossil record. The vast majority of catfish families fulfil this prerequisite, as most of them are represented by extant genera. However, although they constitute a major fish group in terms of distribution, and ecological and taxonomic diversity, the quantitative study of their past morphological variation has been neglected, as fossil specimens are generally identified based on the scarcest remains, that is, complete neurocrania that bear discrete characters. Consequently, a part of freshwater catfish history is unprospected and unknown. In this study, we explored the morphological continuous variation of the humeral plate shape in Synodontis catfishes using Elliptic Fourier Analysis (EFA), and compared extant members and fossil counterparts. We analysed 153 extant specimens of 11 Synodontis species present in the Chad basin, in addition to 23 fossil specimens from the Chadian fossiliferous area of Toros Menalla which is dated around 7 Ma. This highly speciose genus, which is one of the most diversified in Africa, exhibits a rich fossil record with several hundred remains mostly identified as Synodontis sp. The analysis of the outline of the humeral plate reveals that some living morphological types were already represented in the Chad Basin 7 My ago, and allows for the discovery of extinct species. Beside illuminating the complex Neogene evolutionary history of Synodontis, these results underline the interest in the ability of isolated remains to reconstruct a past dynamic history and to validate the relevance of EFA as a tool to explore specific diversity through time. J. Morphol. 277:1486-1496, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Henneguya melini n. sp. (Myxosporea: Myxobolidae), a parasite of Corydoras melini (Teleostei: Siluriformes) in the Amazon region: morphological and ultrastructural aspects.

PubMed

Mathews, Patrick D; Maia, Antônio A M; Adriano, Edson A

2016-09-01

A new species of myxozoan, Henneguya melini sp. n. (Myxosporea: Myxobolidae), was described based on morphologic and ultrastructural features. This is a parasite of the ornamental freshwater fish C. melini from the Rio Negro, and it was found in five of 30 (16.7 %) C. melini examined. The parasite was found in the gill filaments, and the plasmodia had form of round to ellipsoid, with mature and immature spores inside them. The average spore body was 15.5 ± 0.2 μm in length, 4.7 ± 0.1 μm in width, and the tail measured 25.3 ± 0.1 μm in length. The spores showed typical features of the genus Henneguya, with two valves of equal size and two symmetrical polar capsules of 4.8 ± 0.7 μm in length and 1.7 ± 0.3 μm in width. Each polar capsule had a polar filament with five to six turns. Based on morphology (morphologic and ultrastructural data) of the plasmodia and spores and the fact that this is the first report of a Henneguya species in a fish species of the genus Corydoras, it was considered a new myxozoan species.

Biogeographic history and high-elevation adaptations inferred from the mitochondrial genome of Glyptosternoid fishes (Sisoridae, Siluriformes) from the southeastern Tibetan Plateau.

PubMed

Ma, Xiuhui; Kang, Jingliang; Chen, Weitao; Zhou, Chuanjiang; He, Shunping

2015-10-28

The distribution of the Chinese Glyptosternoid catfish is limited to the rivers of the Tibetan Plateau and peripheral regions, especially the drainage areas of southeastern Tibet. Therefore, Glyptosternoid fishes are ideal for reconstructing the geological history of the southeastern Tibet drainage patterns and mitochondrial genetic adaptions to high elevations. Our phylogenetic results support the monophyly of the Sisoridae and the Glyptosternoid fishes. The reconstructed ancestral geographical distribution suggests that the ancestral Glyptosternoids was widely distributed throughout the Brahmaputra drainage in the eastern Himalayas and Tibetan area during the Late Miocene (c. 5.5 Ma). We found that the Glyptosternoid fishes lineage had a higher ratio of nonsynonymous to synonymous substitutions than those found in non-Glyptosternoids. In addition, ωpss was estimated to be 10.73, which is significantly higher than 1 (p-value 0.0002), in COX1, which indicates positive selection in the common ancestral branch of Glyptosternoid fishes in China. We also found other signatures of positive selection in the branch of specialized species. These results imply mitochondrial genetic adaptation to high elevations in the Glyptosternoids. We reconstructed a possible scenario for the southeastern Tibetan drainage patterns based on the adaptive geographical distribution of the Chinese Glyptosternoids in this drainage. The Glyptosternoids may have experienced accelerated evolutionary rates in mitochondrial genes that were driven by positive selection to better adapt to the high-elevation environment of the Tibetan Plateau.

From the inside out: a new species of armoured catfish Corydoras with the description of poorly-explored character sources (Teleostei, Siluriformes, Callichthyidae).

PubMed

Espíndola, V C; Tencatt, L F C; Pupo, F M; Villa-Verde, L; Britto, M R

2018-05-01

A new species of the armoured catfish genus Corydoras is described from the Xingu-Tapajos ecoregion, Brazilian Amazon. The new species can be distinguished from its congeners by having the following combination of features: short mesethmoid, with anterior tip poorly developed, smaller than 50% of bone length; posterior margin of pectoral spine with serrations directed towards spine tip or perpendicularly oriented; infraorbital 2 only in contact with sphenotic; ventral laminar expansion of infraorbital 1 poorly or moderately developed; flank midline covered by small dark brown or black saddles with similar size to remaining markings on body; relatively larger, scarcer and more sparsely distributed dark brown or black spots on body; absence of stripe on flank midline; caudal fin with conspicuous dark brown or black spots along its entire surface; slender body; and strongly narrow frontals. A more comprehensive description of poorly-explored internal character sources, such as the gross morphology of the brain, Weberian apparatus and swimbladder capsule elements is presented. © 2018 The Fisheries Society of the British Isles.

Characterization of 28S rRNA sequences of cestoda parasite Electrotaenia malapteruri Fritsch, 1886 from the Electric catfish Malapterurus electricus (Siluriformes: Malapteruridae).

PubMed

Abdel-Gaber, Rewaida; Alajmi, Reem; Quraishy, Saleh Al; Morsy, Kareem; Rasheid, Khaled Al

2018-07-01

Proteocephalids are cestoda parasites that mostly infect freshwater fish. The present study was carried out to investigate the presence of proteocephalids infecting the electric catfish Malapterurus electricus from Lake Manzala, Kafr El-Sheikh Governorate, Egypt. Morphological characterization revealed the present parasite is a cestoda belonging to the genus Electrotaenia. Morphologically, the recovered worms were characterized by an elongated body measuring 100-127 (120 ± 2) mm long and 0.92-2.11 (2.76 ± 0.1) mm wide. The anterior part of the worm was obvious terminated at a spherical scolex measured 1.12-1.91 (1.72 ± 0.01) mm long and 1.12-1.65 (1.42 ± 0.01) mm wide with a rostellum-like apical organ equipped by 5-6 irregular rows of minute hooklets, as well as four uniloculate suckers with a diameter of 0.13-0.15 (0.14 ± 0.01) mm and covered with microtriches. A long unsegmented neck was observed followed by acraspedote and anapolytic strobila consisted of 85-120 proglottids divided into 50-58 immature, 12-19 mature, and up to 49 gravid proglottids. Molecular characterization based on 28S rRNA sequences was done to confirm the taxonomy of this parasite based on its morphology. It was observed that there was a close identity up to 72.0% with other protocephalid species obtained for comparison from the GenBank. Also, the data obtained revealed that there was high blast scores and low divergence between the present parasite and previously described Electrotaenia malapteruri (acc. no. JX477434). Phylogenetic analysis showed that the parasite sequence in conjunction with existing data investigates the placement of this protocephalid species within Proteocephalidea. It was shown that the present species is deeply embedded in the genus Electrotaenia with close relationships to other Electrotaenia malapteruri as a putative sister taxon. Copyright © 2018 Elsevier B.V. All rights reserved.

A new genus and species of proteocephalidean tapeworm (Cestoda), first parasite found in the driftwood catfish Tocantinsia piresi (Siluriformes: Auchenipteridae) from Brazil.

PubMed

Alves, Philippe Vieira; Chambrier, Alain de; Scholz, Tomas; Luque, Jose Luis

2015-01-01

Frezella gen. n. is proposed to accommodate Frezella vaucheri sp. n. from poorly known auchenipterid fish, Tocantinsia piresi (Miranda Ribeiro), from the Xingú River, one of the principal tributaries of the lower Amazon River in Brazil. The new genus belongs to the Proteocephalinae because of the medullary position of the testes, ovary (yet some follicles penetrate to the cortex on the dorsal side), vitelline follicles and uterus. It differs from other proteocephaline genera in the morphology of the scolex, which includes a metascolex composed of two distinct zones: anterior, strongly wrinkled part posterior to the suckers, and posterior, sparsely folded zone. Frezella can also be differentiated by having the internal longitudinal musculature hypertrophied laterally on both sides, the presence of some ovarian follicles in the cortex on the dorsal side and the presence of additional pair of tiny, thin-walled osmoregulatory canals situated slightly dorsomedian to ventral canals. Frezella vaucheri is the first helminth parasite reported from T. piresi, which occurs in the lower reaches of the Amazon and Tocantins River basins in Brazil.

A large 28S rDNA-based phylogeny confirms the limitations of established morphological characters for classification of proteocephalidean tapeworms (Platyhelminthes, Cestoda)

PubMed Central

de Chambrier, Alain; Waeschenbach, Andrea; Fisseha, Makda; Scholz, Tomáš; Mariaux, Jean

2015-01-01

Abstract Proteocephalidean tapeworms form a diverse group of parasites currently known from 315 valid species. Most of the diversity of adult proteocephalideans can be found in freshwater fishes (predominantly catfishes), a large proportion infects reptiles, but only a few infect amphibians, and a single species has been found to parasitize possums. Although they have a cosmopolitan distribution, a large proportion of taxa are exclusively found in South America. We analyzed the largest proteocephalidean cestode molecular dataset to date comprising more than 100 species (30 new), including representatives from 54 genera (80%) and all subfamilies, thus significantly improving upon previous works to develop a molecular phylogeny for the group. The Old World origin of proteocephalideans is confirmed, with their more recent expansion in South America. The earliest diverging lineages are composed of Acanthotaeniinae and Gangesiinae but most of the presently recognized subfamilies (and genera) appear not to be monophyletic; a deep systematic reorganization of the order is thus needed and the present subfamilial system should be abandoned. The main characters on which the classical systematics of the group has been built, such as scolex morphology or relative position of genital organs in relation to the longitudinal musculature, are of limited value, as demonstrated by the very weak support for morphologically-defined subfamilies. However, new characters, such as the pattern of uterus development, relative ovary size, and egg structure have been identified, which may be useful in defining phylogenetically well-supported subgroups. A strongly supported lineage infecting various snakes from a wide geographical distribution was found. Although several improvements over previous works regarding phylogenetic resolution and taxon coverage were achieved in this study, the major polytomy in our tree, composed largely of siluriform parasites from the Neotropics, remained

Histological development of the digestive system of the Amazonian pimelodid catfish Pseudoplatystoma punctifer.

PubMed

Gisbert, E; Moreira, C; Castro-Ruiz, D; Oztürk, S; Fernández, C; Gilles, S; Nuñez, J; Duponchelle, F; Tello, S; Renno, J F; García-Dávila, C; Darias, M J

2014-11-01

The organogenesis of the digestive system was described in the Amazonian pimelodid catfish species Pseudoplatystoma punctifer from hatching (3.5 mm total length, TL) to 41 days post-fertilization (dpf) (58.1 mm TL) reared at 28°C. Newly hatched larvae showed a simple digestive tract, which appeared as a straight undifferentiated and unfolded tube lined by a single layer of columnar epithelial cells (future enterocytes). During the endogenous feeding period, comprised between 20 and 96 h post-fertilization (3.5 to 6.1 mm TL), the larval digestive system experienced a fast transformation with the almost complete development and differentiation of most of digestive organs (buccopahrynx, oesophagus, intestine, liver and exocrine pancreas). Yolk reserves were not completely depleted at the onset of exogenous feeding (4 dpf, 6.1 mm TL), and a period of mixed nutrition was observed up to 6 to 7 dpf (6.8 to 7.3 mm TL) when yolk was definitively exhausted. The stomach was the organ that latest achieved its complete differentiation, characterized by the development of abundant gastric glands in the fundic stomach between 10 and 15 dpf (10.9 to 15.8 mm TL) and the formation of the pyloric sphincter at the junction of the pyloric stomach and the anterior intestine at 15 dpf (15.8 mm TL). The above-mentioned morphological and histological features observed suggested the achievement of a digestive system characteristic of P. punctifer juveniles and adults. The ontogeny of the digestive system in P. punctifer followed the same general pattern as in most Siluriform species so far, although some species-specific differences in the timing of differentiation of several digestive structures were noted, which might be related to different reproductive guilds, egg and larval size or even different larval rearing practices. According to present findings on the histological development of the digestive system in P. punctifer, some recommendations regarding the rearing practices of this

Impact assessment of the introduction of Cichla kelberi in a large Neotropical reservoir and its lateral lagoons (Upper Paraná River Basin, Brazil).

PubMed

Ferrareze, M; Nogueira, M G

2015-11-01

This study aimed to understand how the introduction of Cichla kelberi in Rosana Reservoir (Paranapanema River) affected the native ichthyofauna. Data on the structure of the small fish fauna assemblage were obtained before and after the introduction of this carnivorous species. Samplings were carried out in February and September of 2004, previously to the register of Cichla kelberi in the reservoir, and after its introduction, November of 2004, January, March, May and August of 2005, February and June of 2006, February and July of 2007, February and October of 2008 and February of 2009. A total of 4,693 fish, belonging to 43 different species was sampled between 2004 and 2009. The order Characiformes was the most abundant, followed by Perciformes and Siluriformes. Comparative analyses, before and after the introduction, could not demonstrate significant changes in composition, richness, abundance, biomass, mean length and diversity of fish. Aquatic insects were the main feeding item of C. kelberi, followed by tetragonopterinae fish. Cannibalism was recorded during the whole study period. The results showed that Cichla cannot deeply affect the ichthyofauna assemblages of a large Neotropical reservoir, at least in a short or medium term period after its introduction. The results also allowed concluding that the introduction of C. kelberi in the reservoir is in the phase 3. In this phase, the specie can survive and reproduce in the new environment; however it is not totally established and disseminated. The reasons for the fact that Cichla is still not dominant in Rosana Reservoir could be related to feeding competition, high rate of cannibalism and the presence of large amount of aquatic macrophytes (refuge zones). In spite of the results, the continuous monitoring of the role of non-native species on the local fish fauna is absolutely necessary because the impacts caused by colonization of this undesirable species can be magnified by complex processes, usually

The cranial cartilages of teleosts and their classification.

PubMed Central

Benjamin, M

1990-01-01

The structure and distribution of cartilages has been studied in 45 species from 24 families. The resulting data have been used as a basis for establishing a new classification. A cartilage is regarded as 'cell-rich' if its cells or their lacunae occupy more than half of the tissue volume. Five classes of cell-rich cartilage are recognised (a) hyaline-cell cartilage (common in the lips of bottom-dwelling cyprinids) and its subtypes fibro/hyaline-cell cartilage, elastic/hyaline-cell cartilage and lipo/hyaline-cell cartilage, (b) Schaffer's Zellknorpel, typified by the cartilage in the gill filaments of most teleosts examined, (c) elastic/cell-rich cartilage, such as that which supports the barbels and oral valves of catfish, e.g. Corydoras metae, (d) fibro/cell-rich cartilage, as in the submaxillary meniscus of Sphaerichthys osphromenoides, (e) cell-rich hyaline and (f) matrix-rich hyaline cartilage--both of which are common in the neurocranium and gill arches of most teleosts. The range of cartilages seen, and the predominant cartilage type, is recorded for each species and a list is provided of the tissues that most typify different organs or regions of the head. As a preliminary pointer to developmental relationships between the cartilages, note was taken of gradual transitions between one cartilage and another. It is suggested that hyaline-cell cartilage occupies a key position in teleosts as the most labile of the supporting tissues and is highly characteristic of Cypriniformes. The cartilage that best resembles mammalian hyaline cartilage (matrix-rich hyaline cartilage) has a very conservative distribution in different skeletal elements and the least number of associations with other tissues. It is well represented in Siluriformes. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 15 Fig. 16 Fig. 17 Fig. 18 Fig. 19 Fig. 20 Fig. 24 Fig. 25 Fig. 26 Fig. 27 PMID:2384333

Salinity tolerance of non-native suckermouth armoured catfish (Loricariidae: Pterygoplichthys) in south-eastern Mexico: implications for invasion and dispersal

USGS Publications Warehouse

Capps, Krista A.; Nico, Leo G.; Mendoza-Carranza, Manuel; Arevalo-Frias, Wendi; Ropicki, Andrew J.; Heilpern, Sebastian A.; Rodiles-Hernandez, Rocio

2011-01-01

1. Salinity tolerance is one of several important physiological attributes that determine invasion success and the pattern of dispersal of introduced aquatic organisms. Introduced freshwater fishes able to tolerate elevated salinities have the potential to invade and exploit brackish-water (mixohaline) environments and use estuaries and coastal waters as 'bridges' for dispersing from one coastal river system to another. 2. Several members of the neotropical suckermouth armoured catfish genus Pterygoplichthys (Siluriformes: Loricariidae) have established non-native populations in inland waters of North and Central America, Asia and islands in the Caribbean, and Pacific and Indian oceans. Loricariids are generally considered to be strictly freshwater; but a few naturally occur in mesohaline habitats. 3.Catch and habitat data from 2004–2005 and 2009–2011 fish surveys in the Grijalva–Usumacinta River delta region (south-eastern Mexico) confirmed that introduced Pterygoplichthys populations established in upstream freshwater sites (where these catfish are abundant) have recently dispersed into downstream oligohaline and mesohaline estuarine habitats. During 2009–2011 surveys, these non-native catfish — tentatively identified as P. pardalis or its hybrids — were found in sites with salinities ranging from 1 to 8 ppt (mean 5.2 ppt). 4.Acute-salinity experiments were conducted with Pterygoplichthys (110–302 mm standard length, N=140) captured in the Grijalva–Usumacinta Basin to determine upper salinity tolerance levels. Tests demonstrated that individuals maintained in salinities of 0.2 ppt were able to survive abrupt (acute) exposure to salinities up to 10 ppt with little mortality over 10 days (240 h experimental endpoint). A few individuals survived abrupt exposure to 11 and 12 ppt for 20 or more hours, although none survived more than a few hours at 16 ppt or greater. 5.These field and experimental results provide quantitative evidence that non

The phylogenetic relationships among non-diplomystid catfishes as inferred from mitochondrial cytochrome b sequences; the search for the ictalurid sister taxon (Otophysi: Siluriformes).

PubMed

Hardman, Michael

2005-12-01

The relationships among families of catfishes are poorly understood and have yet to be the subject of a comprehensive investigation with molecular data. Existing phylogenetic hypotheses are based on morphological data and incompletely resolved. This study analyzed complete sequences of mitochondrial gene cytochrome b for 170 species from 29 of 33 extant families, and focused on the relationships of Ictaluridae to other catfishes. In addition to previous phylogenetic studies, the fossil record, paleogeography, biogeography, and distribution of extant catfish families collectively suggest the location (if extant) of the ictalurid sister taxon to be Northern or Eastern Asia. Of the extant catfishes currently native to this area and included in this analysis, parsimony and Bayesian likelihood analyses recovered Cranoglanis bouderius as the most proximal sister taxon of Ictaluridae. Seemingly, ictalurids and cranoglanidids represent another biogeographic component linking freshwater fishes of North America and eastern Asia, e.g., catostomids and paddlefishes. The results coupled with present-day catfish distributions and inferences from the fossil record collectively suggest the ancestor of Ictaluridae to have invaded freshwaters of North America at the close of the Cretaceous through northeastern Asia and northwestern North America. Other superfamilial nodes supported the results of previous phylogenetic studies of narrower taxonomic scope. Several novel relationships were recovered (including a clade composed of Pimelodidae, Pseudopimelodidae, and Heptapteridae) and these along with sources of systematic error are discussed. A broad sampling of Bagridae permitted an examination of intergeneric relationships within this family and in light of recent morphological and molecular studies.

A new Brachyrhamdia (Siluriformes: Heptapteridae) from Rio Japurá basin, Brazil, with comments on its phylogenetic affinities, biogeography and mimicry in the genus.

PubMed

Slobodian, Veronica; Bockmann, Flávio Alicino

2013-01-01

Brachyrhamdia thayeria is herein described as a new heptapterid species from Rio Japuré, a left margin tributary of the Rio Solimões, Amazonas basin, Brazil. The new species is diagnosed from all its congeners by having a putative autapomorphy: dark oblique stripe across the caudal peduncle, originating below the anterior half of adipose fin and ending at base of rays of ventral caudal-fin lobe. Brachyrhamdia thayeria is considered closely related to B. imitator and B. rambarrani with which it shares a low vertebral number and absence of lateral stripe along trunk. The new species shares exclusively with B. rambarrani the presence of a dark conspicuous bar along the dorsolateral region of trunk, a putative synapomorphy. Brachyrhamdia are distributed in lowland regions of northern South America where they inhabit small streams with running waters. The new species appears to have a mimetic association with the syntopic callichthyid Corydoras arcuatus. Herein, we argue in favor of the hypothesis that the interaction between species of Brachyrhamdia and Pimelodella or Corydoras is Müllerian mimicry.

Neotropical Monogenoidea. 53. Gyrodactylus corydori sp. n. and redescription of Gyrodactylus anisopharynx (Gyrodactylidea: Gyrodactylidae), parasites of Corydoras spp. (Siluriformes: Callichthyidae) from southern Brazil.

PubMed

Bueno-Silva, Marlus; Boeger, Walter A

2009-03-01

Morphometric analyses are used to evaluate the taxonomic status of two sympatric variants of Gyrodactylus anisopharynx Popazoglo et Boeger, 2000 (forma "large-pharynx" and forma "small-pharynx"). The parasites were collected from the Piraquara River and the Miringuava River, State of Paraná, Brazil, between February 2005 and May 2006. A total of 132 parasites were measured from two hosts, Corydoras ehrhardti Steindachner and Corydoras paleatus (Jenyns). Eleven morphological features of the haptoral sclerites and pharynx were measured and analysed by discriminant analysis and principal components analysis. The results indicate that the observed morphological variation cannot be associated to intraspecific variation or phenotypic plasticity (P < 0.0001). Consequently, the two variants previously allocated in G. anisopharynx represent two independent species. Since the holotype was defined as the variant "large-pharynx", Gyrodactylus corydori sp. n. is proposed to accommodate specimens previously reported as "small-pharynx" variant of G. anisopharynx. Morphometric analyses showed that the hook, the anchor, and the pharyngeal bulb are significantly distinct (P < 0.0001) between G. corydori sp. n. and G. anisopharynx (s.s.). The new species is characterized by having hooks with point moderately curved, robust convex heel, convex shelf, toe concave moderately pointed with depression; deep bar with two submedial, posterior projections; anchors with robust superficial root; superficial bar with two small anterolateral projections; and male copulatory organ armed with two rows of spinelets.

The relative importance of body size and paleoclimatic change as explanatory variables influencing lineage diversification rate: an evolutionary analysis of bullhead catfishes (Siluriformes: Ictaluridae).

PubMed

Hardman, Michael; Hardman, Lotta M

2008-02-01

We applied Bayesian phylogenetics, divergence time estimation, diversification pattern analysis, and parsimony-based methods of ancestral state reconstruction to a combination of nucleotide sequences, maximum body sizes, fossils, and paleoclimate data to explore the influence of an extrinsic (climate change) and an intrinsic (maximum body size) factor on diversification rates in a North American clade of catfishes (Ictaluridae). We found diversification rate to have been significantly variable over time, with significant (or nearly significant) rate increases in the early history of Noturus. Though the latter coincided closely with a period of dramatic climate change at the Eocene-Oligocene boundary, we did not detect evidence for a general association between climate change and diversification rate during the entire history of Ictaluridae. Within Ictaluridae, small body size was found to be a near significant predictor of species richness. Morphological stasis of several species appears to be a consequence of a homoplastic increase in body size. We estimated the maximum standard length of the ictalurid ancestor to be approximately 50 cm, comparable to Eocene ictalurids (Astephus) and similar to modern sizes of Ameiurus and their Asian sister-taxon Cranoglanis. During the late Paleocene and early Eocene, the ictalurid ancestor diversified into the lineages represented by the modern epigean genera. The majority of modern species originated in the Oligocene and Miocene, most likely according to a peripheral isolates model of speciation. We discuss the difficulties of detecting macroevolutionary patterns within a lineage history and encourage the scrutiny of the terminal Eocene climatic event as a direct promoter of diversification.

A new species of Pareiorhaphis (Siluriformes: Loricariidae) from the headwaters of the Arroio Garapiá, coastal drainage of Rio Grande do Sul state, Brazil.

PubMed

Pereira, Edson H L; Lehmann, Pablo A; Schvambach, Lucas J; Reis, Roberto E

2015-10-30

Pareiorhaphis garapia, new species, is described based on specimens collected in the headwaters of the Arroio Garapiá, Rio Maquiné basin, a coastal drainage of Rio Grande do Sul State, southern Brazil. The new species is distinguished from all other Pareiorhaphis species in having the nuchal plate covered by thick skin, the exposed posterior process of the cleithrum comparatively narrow, and the last segment of the preopercular ramus of the latero-sensory canal reduced to an ossified tubule. The absence of a dorsal-fin spinelet, the reduced number of plates in the dorsal and mid-dorsal series of lateral plates, and morphometric traits also distinguish the new species from its congeners. The restricted geographic distribution of P. garapia, endemic to a headwater stream of the Rio Maquiné basin, and the syntopic occurrence of P. nudulus are discussed.

The fate of the duplicated androgen receptor in fishes: a late neofunctionalization event?

PubMed Central

2008-01-01

Background Based on the observation of an increased number of paralogous genes in teleost fishes compared with other vertebrates and on the conserved synteny between duplicated copies, it has been shown that a whole genome duplication (WGD) occurred during the evolution of Actinopterygian fish. Comparative phylogenetic dating of this duplication event suggests that it occurred early on, specifically in teleosts. It has been proposed that this event might have facilitated the evolutionary radiation and the phenotypic diversification of the teleost fish, notably by allowing the sub- or neo-functionalization of many duplicated genes. Results In this paper, we studied in a wide range of Actinopterygians the duplication and fate of the androgen receptor (AR, NR3C4), a nuclear receptor known to play a key role in sex-determination in vertebrates. The pattern of AR gene duplication is consistent with an early WGD event: it has been duplicated into two genes AR-A and AR-B after the split of the Acipenseriformes from the lineage leading to teleost fish but before the divergence of Osteoglossiformes. Genomic and syntenic analyses in addition to lack of PCR amplification show that one of the duplicated copies, AR-B, was lost in several basal Clupeocephala such as Cypriniformes (including the model species zebrafish), Siluriformes, Characiformes and Salmoniformes. Interestingly, we also found that, in basal teleost fish (Osteoglossiformes and Anguilliformes), the two copies remain very similar, whereas, specifically in Percomorphs, one of the copies, AR-B, has accumulated substitutions in both the ligand binding domain (LBD) and the DNA binding domain (DBD). Conclusion The comparison of the mutations present in these divergent AR-B with those known in human to be implicated in complete, partial or mild androgen insensitivity syndrome suggests that the existence of two distinct AR duplicates may be correlated to specific functional differences that may be connected to the well

The role of the hydrological cycle on the distribution patterns of fish assemblages in an Andean stream.

PubMed

Ríos-Pulgarín, M I; Barletta, M; Mancera-Rodríguez, N J

2016-07-01

The seasonal and interannual changes of the fish assemblage in the main channel and littoral zone of the Guarinó River, a torrential system located in the Colombian Andean foothills, were examined in relation to the physical and chemical environmental changes associated with the hydrological cycle and the El Niño-La Niña-Southern Oscillation (ENSO) between 2007 and 2010. Four samplings per year (in dry season and high water) were performed. Environmental variables (temperature, pH, conductivity, turbidity, oxygen, total nitrogen, orthophosphate, depth and flow rate) were contrasted with ANOVAs and a discriminant analysis to establish temporal patterns. Biological descriptors (richness, density and biomass) were contrasted with ANCOVAs. The temporal patterns of the taxonomic and functional composition and the density of the fish assemblages were examined with respect to environmental variables through canonical discriminant analysis per habitat. Interannual differences were significant with regard to density and richness for the main channel habitat; while in the littoral zone, the differences were significant between both the year and seasons. Discriminant analysis showed variations in species composition and relative abundance between the main channel and the littoral zone under contrasting hydrological conditions of El Niño-La Niña. High flows from 2008 to 2009 (La Niña) favoured resident species (e.g. Creagrutus magdalenae) and small benthic Siluriformes (e.g. Chaetostoma spp.), but was limited to migratory species (e.g. Prochilodus magdalenae). From 2009 to 2010 (El Niño), the most common species were reduced and rare species increased. River flow, temperature and oxygen were the variables that had the largest influences on the seasonal and interannual differences in the fish assemblage structure of the Guarinó River. The results suggested that the presence and abundance of species and functional groups in different habitats were regulated by stochastic

A review of estuarine fish research in South America: what has been achieved and what is the future for sustainability and conservation?

PubMed

Blaber, S J M; Barletta, M

2016-07-01

Estuarine fish research in South America began in the early 20th Century, but it is only within the last 40 years that detailed studies have been undertaken. This review firstly summarizes research results from South American estuaries by geographic area, starting with the temperate south-east, then the temperate-sub-tropical transition zone in Brazil, then the semi-arid and tropical estuaries of north and north-east Brazil including the Amazon complex, then the north and Caribbean coasts and finally down the Pacific coast of the continent. They include almost all types of estuarine systems, from large open systems (e.g. the temperate Rio de La Plata and tropical Amazon) to extensive coastal lakes (e.g. the temperate Patos Lagoon and tropical Cienega Grande de Santa Marta). They encompass a broad range of climatic and vegetation types, from saltmarsh systems in the south-east and fjords in the south-west to both arid and humid tropical systems, dominated by mangroves in the north. Their tidal regimes range from microtidal (e.g. Mar Chiquita, Argentina) through mesotidal (e.g. Goiana, Brazil) to macrotidal in the Amazon complex where they can exceed 7 m. The review uses where possible the recent standardization of estuarine fish categories and guilds, but the ways that fishes use tropical South American systems may necessitate further refinements of the categories and guilds, particularly in relation to freshwater fishes, notably the Siluriformes, which dominate many north and north-east South American systems. The extent to which South American studies contribute to discussions and paradigms of connectivity and estuarine dependence is summarized, but work on these topics has only just begun. The anthropogenic issue of pollution, particularly in relation to heavy metals and fishes and fisheries in estuaries is more advanced, but the possible effects of climate change have barely been addressed. Studies around conservation and management are briefly reviewed and

Ecology of the parasitic endohelminth community of Pseudoplatystoma fasciatum (Linnaeus, 1776) (Siluriformes: Pimelodidae) from the Aquidauana River, Pantanal, State of Mato Grosso do Sul, Brazil.

PubMed

Campos, C M; Fonseca, V E; Takemoto, R M; Moraes, F R

2009-02-01

This study investigated the structure and diversity of the endohelminth community and its interactions with Pseudoplatystoma fasciatum, caught in the Aquidauana River, in the State of Mato Grosso do Sul, Brazil. Ten helminth species were represented in 1,228 specimens of parasites found in the intestine and mesentery of 33 specimens of P. fasciatum. Cestodes were observed in the intestine, while nematodes Cucullanus sp. in the mesentery. Contracaecum sp. Type 1, Spatulifer rugosa and Choanoscolex abscisus showed the highest mean intensity and mean abundance and Nomimoscolex sudobin showed the highest prevalence. Simpson's index indicated dominance in the endohelminth infracommunities (C = 1.0792) and Choanoscolex abscisus was considered the central species. A clumped pattern of dispersion according to Green's index was related. 69.69% of hosts analyzed had between 2 and 5 species of endohelminths. Mean diversity was H = 0.5517 (SD = 0.4209). Two pairs of species showed significant positive association and four pairs presented significant positive correlation among abundance data. Significant negative correlations between total length and prevalence and abundance of Peltydocotyle rugosa and Nomimoscolex sudobim were found. However, no significant correlation was observed between condition factor and abundance, as well as total length and diversity. There was significant prevalence of Harriscolex kaparari in male hosts.

Ultrastructural particularities of the spermatozoon of the cestode Electrotaenia malopteruri (Fritsch, 1886) (Proteocephalidae: Gangesiinae), a parasite of Malapterurus electricus (Siluriformes: Malapteruridae) from the river Nile, Egypt.

PubMed

Brunanská, Magdaléna; Scholz, Tomás; Ibraheem, Mohammed Hassan

2004-06-01

The fine structure of the mature spermatozoon of the tapeworm Electrotaenia malopteruri (Fritsch, 1886), a member of a supposedly primitive group of proteocephalidean tapeworms (Proteocephalidae: Gangesiinae), was studied by transmission electron microscopy for the first time. The mature spermatozoon of E. malopteruri is filiform, tapers at both extremities, and contains two axonemes of 9+"1" trepaxonematan type. A helicoidal crested body (60-150 nm thick) is present at the anterior extremity of the gamete. The twisting cortical microtubules (CM) line the periphery of the spermatozoon continuously. The nucleus, a fine cord of moderately condensed chromatin, occupies the middle part (region III) of the spermatozoon. The slightly electron-dense cytoplasm contains electron-dense granules in regions II and III and becomes more electron-dense at the end of region IV. The anterior and posterior extremities of the spermatozoon contain a single axoneme. Two modes of disorganisation of the axoneme at the posterior end of the mature spermatozoa are described for the first time in cestodes. The present data also indicate that the sperm ultrastructure of E. malapteruri shows some characters typical for onchobothriid tetraphyllideans, but it resembles that of Cyclophyllidea in the arrangement of twisting of the CM.

Temporal and spatial distribution of young Brachyplatystoma spp. (Siluriformes: Pimelodidae) along the rapids stretch of the Madeira River (Brazil) before the construction of two hydroelectric dams.

PubMed

Cella-Ribeiro, A; Assakawa, L F; Torrente-Vilara, G; Zuanon, J; Leite, R G; Doria, C; Duponchelle, F

2015-04-01

Monthly (April 2009 to May 2010) bottom-trawl sampling for Brachyplatystoma species along the rapids stretch of the Madeira River in Brazil revealed that Brachyplatystoma rousseauxii larvae and juveniles were present in low abundances in all areas and during all hydrological periods. The presence of larvae and juveniles throughout the hydrological cycle suggests asynchronous spawning in the headwaters of the Madeira River. © 2015 The Fisheries Society of the British Isles.

Description of a new catfish genus (Siluriformes, Loricariidae) from the Tocantins River basin in central Brazil, with comments on the historical zoogeography of the new taxon

PubMed Central

Silva, Gabriel S. C.; Roxo, Fábio F.; Ochoa, Luz E.; Oliveira, Claudio

2016-01-01

Abstract This study presents the description of a new genus of the catfish subfamily Neoplecostominae from the Tocantins River basin. It can be distinguished from other neoplecostomine genera by the presence of (1) three hypertrophied bicuspid odontodes on the lateral portion of the body (character apparently present in mature males); (2) a large area without odontodes around the snout; (3) a post-dorsal ridge on the caudal peduncle; (4) a straight tooth series in the dentary and premaxillary rows; (5) the absence of abdominal plates; (6) a conspicuous series of enlarged papillae just posterior to the dentary teeth; and (7) caudal peduncle ellipsoid in cross section. We used maximum likelihood and Bayesian methods to estimate a time-calibrated tree with the published data on 116 loricariid species using one nuclear and three mitochondrial genes, and we used parametric biogeographic analyses (DEC and DECj models) to estimate ancestral geographic ranges and to infer the colonization routes of the new genus and the other neoplecostomines in the Tocantins River and the hydrographic systems of southeastern Brazil. Our phylogenetic results indicate that the new genus and species is a sister taxon of all the other members of the Neoplecostominae, originating during the Eocene at 47.5 Mya (32.7–64.5 Mya 95% HPD). The present distribution of the new genus and other neoplecostomines may be the result of a historical connection between the drainage basins of the Paraguay and Paraná rivers and the Amazon basin, mainly through headwater captures. PMID:27408594

An Unusual Accumulation of Ribosomal Multigene Families and Microsatellite DNAs in the XX/XY Sex Chromosome System in the Trans-Andean Catfish Pimelodella cf. chagresi (Siluriformes:Heptapteridae).

PubMed

Conde-Saldaña, Cristhian Camilo; Barreto, Cynthia Aparecida Valiati; Villa-Navarro, Francisco Antonio; Dergam, Jorge Abdala

2018-02-01

This work constitutes the first cytogenetic characterization of a trans-Andean species of Heptapteridae. The catfish Pimelodella cf. chagresi from the Upper Rio Magdalena was studied, applying standard cytogenetic techniques (Giemsa, C-banding, and argyrophilic nucleolar organizer region [Ag-NOR]) and fluorescence in situ hybridization techniques using repetitive DNA probes: microsatellites (CA 15 and GA 15 ) and ribosomal RNA (rRNA) multigene families (18S and 5S recombinant DNA [rDNA] probes). The species showed a unique diploid chromosome number 2n = 50 (32m [metacentrics] +14sm [submetacentrics] +4st [subtelocentrics]) and a XX/XY sex chromosomal system, where the heteromorphic Y-chromosome revealed a conspicuous accumulation of all the assayed domains of repetitive DNA. P. cf. chagresi karyotype shares common features with other Heptapteridae, such as the predominance of metacentric and submetacentric chromosomes, and one pair of subtelomeric nucleolar organizer regions (NORs). These results reflect an independent karyological identity of a trans-Andean species and the relevance of repetitive DNA sequences in the process of sex chromosome differentiation in fish; it is the first case of syntenic accumulation of rRNA multigene families (18S and 5S rDNA) and microsatellite sequences (CA 15 and GA 15 ) in a differentiated sex chromosome in Neotropical fish.

Can DNA barcoding accurately discriminate megadiverse Neotropical freshwater fish fauna?

PubMed Central

2013-01-01

Background The megadiverse Neotropical freshwater ichthyofauna is the richest in the world with approximately 6,000 recognized species. Interestingly, they are distributed among only 17 orders, and almost 80% of them belong to only three orders: Characiformes, Siluriformes and Perciformes. Moreover, evidence based on molecular data has shown that most of the diversification of the Neotropical ichthyofauna occurred recently. These characteristics make the taxonomy and identification of this fauna a great challenge, even when using molecular approaches. In this context, the present study aimed to test the effectiveness of the barcoding methodology (COI gene) to identify the mega diverse freshwater fish fauna from the Neotropical region. For this purpose, 254 species of fishes were analyzed from the Upper Parana River basin, an area representative of the larger Neotropical region. Results Of the 254 species analyzed, 252 were correctly identified by their barcode sequences (99.2%). The main K2P intra- and inter-specific genetic divergence values (0.3% and 6.8%, respectively) were relatively low compared with similar values reported in the literature, reflecting the higher number of closely related species belonging to a few higher taxa and their recent radiation. Moreover, for 84 pairs of species that showed low levels of genetic divergence (<2%), application of a complementary character-based nucleotide diagnostic approach proved useful in discriminating them. Additionally, 14 species displayed high intra-specific genetic divergence (>2%), pointing to at least 23 strong candidates for new species. Conclusions Our study is the first to examine a large number of freshwater fish species from the Neotropical area, including a large number of closely related species. The results confirmed the efficacy of the barcoding methodology to identify a recently radiated, megadiverse fauna, discriminating 99.2% of the analyzed species. The power of the barcode sequences to identify

An uncommon co-localization of rDNA 5S with major rDNA clusters in Callichthyidae (Siluriformes): a report case in Corydoras carlae Nijssen & Isbrücker, 1983

PubMed Central

da Rocha, Rafael Henrique; Baumgärtner, Lucas; Paiz, Leonardo Marcel; Margarido, Vladimir Pavan; Fernandes, Carlos Alexandre; Gubiani, Éder André

2016-01-01

Abstract Corydoras Lacepède, 1803 is the most specious genus of Corydoradinae subfamily and many of its species are still unknown in relation to molecular cytogenetic markers. However, the diploid number and karyotypic formula were recorded for many species of this group. In current study, we provided the first cytogenetic information of Corydoras carlae Nijssen & Isbrücker, 1983, an endemic fish species from Iguassu River basin, Paraná State, Brazil. The individuals were collected in Florido River, a tributary of Iguassu River and analysed with respect to diploid number, heterochromatin distribution pattern, Ag-NORs and mapping of 5S and 18S ribosomal genes. The karyotype of this species comprises 46 chromosomes arranged in 22m+22sm+2st. The heterochromatin is distributed in centromeric and pericentromeric positions in most of the chromosomes, and also associated with NORs. The Ag-NORs were detected in the terminal position on the long arm of the metacentric pair 6. The double-FISH technique showed that 5S rDNA and 18S rDNA were co-localized in the terminal portion on the long arm of the metacentric pair 6. This condition of co-localization of ribosomal genes in Corydoras carlae seems to represent a marker for this species. PMID:28123681

An uncommon co-localization of rDNA 5S with major rDNA clusters in Callichthyidae (Siluriformes): a report case in Corydoras carlae Nijssen & Isbrücker, 1983.

PubMed

da Rocha, Rafael Henrique; Baumgärtner, Lucas; Paiz, Leonardo Marcel; Margarido, Vladimir Pavan; Fernandes, Carlos Alexandre; Gubiani, Éder André

2016-01-01

Corydoras Lacepède, 1803 is the most specious genus of Corydoradinae subfamily and many of its species are still unknown in relation to molecular cytogenetic markers. However, the diploid number and karyotypic formula were recorded for many species of this group. In current study, we provided the first cytogenetic information of Corydoras carlae Nijssen & Isbrücker, 1983, an endemic fish species from Iguassu River basin, Paraná State, Brazil. The individuals were collected in Florido River, a tributary of Iguassu River and analysed with respect to diploid number, heterochromatin distribution pattern, Ag-NORs and mapping of 5S and 18S ribosomal genes. The karyotype of this species comprises 46 chromosomes arranged in 22m+22sm+2st. The heterochromatin is distributed in centromeric and pericentromeric positions in most of the chromosomes, and also associated with NORs. The Ag-NORs were detected in the terminal position on the long arm of the metacentric pair 6. The double-FISH technique showed that 5S rDNA and 18S rDNA were co-localized in the terminal portion on the long arm of the metacentric pair 6. This condition of co-localization of ribosomal genes in Corydoras carlae seems to represent a marker for this species.

Physical mapping of the 5S and 18S rDNA in ten species of Hypostomus Lacépède 1803 (Siluriformes: Loricariidae): evolutionary tendencies in the genus.

PubMed

Bueno, Vanessa; Venere, Paulo César; Thums Konerat, Jocicléia; Zawadzki, Cláudio Henrique; Vicari, Marcelo Ricardo; Margarido, Vladimir Pavan

2014-01-01

Hypostomus is a diverse group with unclear aspects regarding its biology, including the mechanisms that led to chromosome diversification within the group. Fluorescence in situ hybridization (FISH) with 5S and 18S rDNA probes was performed on ten Hypostomini species. Hypostomus faveolus, H. cochliodon, H. albopunctatus, H. aff. paulinus, and H. topavae had only one chromosome pair with 18S rDNA sites, while H. ancistroides, H. commersoni, H. hermanni, H. regani, and H. strigaticeps had multiple 18S rDNA sites. Regarding the 5S rDNA genes, H. ancistroides, H. regani, H. albopunctatus, H. aff. paulinus, and H. topavae had 5S rDNA sites on only one chromosome pair and H. faveolus, H. cochliodon, H. commersoni, H. hermanni, and H. strigaticeps had multiple 5S rDNA sites. Most species had 18S rDNA sites in the telomeric region of the chromosomes. All species but H. cochliodon had 5S rDNA in the centromeric/pericentromeric region of one metacentric pair. Obtained results are discussed based on existent phylogenies for the genus, with comments on possible dispersion mechanisms to justify the variability of the rDNA sites in Hypostomus.

Ontogenetic and seasonal shifts in the diet of the pemecou sea catfish Sciades herzbergii (Siluriformes: Ariidae), from a macrotidal mangrove creek in the Curuçá estuary, northern Brazil.

PubMed

Giarrizzo, Tommaso; Saint-Paul, Ulrich

2008-06-01

The feeding ecology of pemecou sea catfish (Sciades herzbergii) was studied bimonthly from September 2003 to July 2004 in a macrotidal mangrove creek at Curuçá estuary, Brazil. Feeding activity and relative importance of prey groups were assessed in 528 and 226 specimens (6.2 to 36.0 cm total length), respectively, using stomach contents. A total of 1 820 specimens were caught. The fish left the creek with an average of 2.2% of their body weight in prey. Feeding activity was lower in the dry season (September and November 2003) than in the rainy season (January to May 2004). The diet was dominated by Ocypodidae and Grapsidae. Feeding strategies of the pemecou sea catfish indicated a slight variation between the diets of adults and juveniles; however; the main factor leading to diversification in the diet were the seasons. Opportunistic feeding behavior was observed in the dry season, shifting to more specialized feeding in the wet season. This temporal diet shift may be explained by the environmental seasonal variations (e.g., transparency of the water, high water level) in the intertidal mangrove creek habitat.

Neotropical Monogenoidea 37. Redescription of Gyrodactylus superbus (Szidat, 1973) comb. n. and description of two new species of Gyrodactylus (Gyrodactylidea: Gyrodactylidae) from Corydoras paleatus and C. ehrhardti (Teleostei: Siluriformes: Callichthyidae) of Southern Brazil.

PubMed

Popazoglo, F; Boeger, W A

2000-01-01

Two new species of Gyrodactylus (Gyrodactylidae) are described from Corydoras paleatus (Jenyns) and Corydoras ehrhardti Steindachner (Callichthyidae) of Rio Piraquara, Municipality of Piraquara, near Curitiba, Paraná, Brazil: Gyrodactylus anisopharynx sp. n. and Gyrodactylus samirae sp. n. These species are unique among the known Neotropical species of Gyrodactylus by the combination of several characters. Gyrodactylus anisopharynx is characterised by having hooks with point evenly curved, toe moderately pointed, round convex heel, straight sloping shelf, superficial bar with anterolateral projections and male copulatory organ armed with two rows of spinelets. Two variants of G. anisopharynx, of distinct pharynx size, are recognised: forma "large-pharynx" and forma "small-pharynx". Gyrodactylus samirae is characterised by having hook with straight shaft, short slightly recurved point, truncate toe, trapezoidal heel, shelf slightly concave, orthogonal to shaft; anchors with relatively short superficial root; superficial bar with extremities lightly expanded; and male copulatory organ armed with two rows of spinelets. Paragyrodactyloides superbus (Szidat, 1973) is redescribed and transferred to Gyrodactylus based on examination of type and new specimens. Features previously considered as diagnostic for the genus are misinterpretations or primitive characters for Gyrodactylus spp.

Revision of the amphiamerican Neotetraonchus Bravo-Hollis, 1968 (Monogenoidea: Dactylogyridae), with a description of N. vegrandis n. sp. from the gill lamellae of the blue sea catfish Ariopsis guatemalensis (Siluriformes: Ariidae) off the Pacific Coast of Mexico.

PubMed

Kritsky, Delane C; Mendoza-Franco, Edgar F; Bullard, Stephen A; Vidal-Martínez, Victor M

2009-09-01

Neotetraonchus Bravo-Hollis, 1968 is revised and reassigned to the Dactylogyridae Bychowsky, 1933 based on examinations of specimens representing four species from the gill lamellae of sea catfishes (Ariidae). The monotypic Neotetraonchidae Bravo-Hollis, 1968 is placed in synonymy with the Dactylogyridae. Neotetraonchus bychowskyi Bravo-Hollis, 1968 (type-species), is redescribed from the tete sea catfish Ariopsis seemanni (Günther) (type-host) in the eastern Pacific Ocean off Panama (new geographical record). Neotetraonchus vegrandis n. sp. is described from the blue sea catfish A. guatemalensis (Günther) off the Pacific Coast of Mexico. Neotetraonchus bravohollisae Paperna, 1977 is redescribed from the hardhead sea catfish A. felis (L.) in the Gulf of Mexico off the Yucatan Peninsula. Neotetraonchus felis (Hargis, 1955) Paperna, 1977 is redescribed from A. felis in the Gulf of Mexico off Mississippi and the Yucatan Peninsula (new geographical record). Morphological similarities between species of Neotetraonchus suggest the likely presence of geminate species pairs flanking the Isthmus of Panama.

Fish as a proxy for African paleogeography: results from both extant and fossil taxa and prospects to constrain faunal exchange pathway through time

NASA Astrophysics Data System (ADS)

Otero, Olga; Joordens, Josephine; Dettai, Agnès; Christ, Leemans; Pinton, Aurélie

2016-04-01

reveal ancient distributions. The further we are going back in time the more they will constitute most of or the whole relevant sample. Our results also suggest that information on the (paleo)ecology of the fish provides useful data notably to qualify the aquatic systems that have prevailed at the time of connection between basins. So, changes in basin geomorphology constrain fish evolution, and thus we are able to reconstruct and date these changes thanks to fish evolution studies. Since it is widely agreed that the identification of corridors and barriers is critical to understand faunal exchange, we are convinced that for each case study, we can identify the fish (either fossil or extant) that will provide a relevant "geomorphological model". To validate this approach, our current project aims to identify the exchange corridor that may have intermittently existed between the Chad and Turkana basins during the last 3 million years [6]. These corridors may have constituted possible pathways for interbasinal exchange of large mammals at a key time period of Australopithecine evolution. We will end our presentation with preliminary results concerning phylogeography of the extant catfish Synodontis schall, one of our three model species. [1] Pinton A., Otero O. in progress - How much do fish distribution depend on drainage system history? the case study of continental Africa. [2] Pinton A., Agnèse J.F., Paugy D., Otero O. 2013 - A large-scale phylogeny of Synodontis (Mochokidae, Siluriformes) reveals the influence of geological events on continental diversity during the Cenozoic. Molecular Phylogenetics and Evolution, 66 (2013): 1027-1040. [3] Otero O. 2011 - Current knowledge and new assumptions on the evolutionary history of the African lungfish, Protopterus, based on a review of its fossil record. Fish & Fisheries, 2011(12): 235-255. [4] Otero O., Pinton A., Mackaye H.T., Likius A., Vignaud P., Brunet M. 2009 - Fishes and palaeogeography of the African drainage basins