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A systematic revision of Tatia (Siluriformes: Auchenipteridae: Centromochlinae)
Sarmento-Soares, Luisa Maria;Martins-Pinheiro, Ronaldo Fernando;
Neotropical Ichthyology , 2008, DOI: 10.1590/S1679-62252008000300022
Abstract: the auchenipterid catfish genus tatia is revised. twelve species are recognized including three described as new. tatia is diagnosed by the hyomandibula elongated anterodorsally, the anal-fin base of adult males reduced in length, and the caudal peduncle laterally compressed and deep with a middorsal keel. tatia aulopygia occurs in the madeira river drainage and is distinguished by the reduced cranial fontanel in adults and male modified anal fin with middle rays reduced in length. tatia boemia, known from the upper uruguay river drainage, is distinguished by its unique color pattern with dark chromatophores on the sides of body. tatia brunnea from river basins in suriname and french guiana and the negro river drainage, amazon basin, is recognized by its wide head and mouth and by the male modified anal fin with sharply pointed tip. tatia dunni, from the upper amazon basin, is recognized by its narrow head, long postcleithral process in some specimens, and body coloration with irregular blotches or stripes. tatia galaxias, endemic to the orinoco river basin, is distinguished by its large eye and short snout. tatia gyrina, distributed in the upper and central amazon basin and in northern suriname, has a uniquely reduced mesethmoid, slightly protruding lower jaw, second nuchal plate with slightly concave lateral borders, third nuchal plate reduced, small prevomer, low number of ribs, low number of vertebrae and sexual dimorphism regarding intumescent male genital papilla. tatia intermedia, recorded from central and lower amazon basin, tocantins river, and coastal drainages in guyana, suriname, french guiana, and eastern pará state, brazil, is distinguished by the short postcleithral process, small eye and long snout. tatia neivai, from the upper paraná river , paraguay river and upper paraíba do sul river basin, is distinguished by its unique vertebral count and caudal-fin coloration consisting of transverse dark bars. tatia strigata, from central amazon basin and neg
A new species of the genus Pimelodus La Cépède, 1803 from the rio Igua?u basin and a reappraisal of Pimelodus ortmanni Haseman, 1911 from the rio Paraná system, Brazil (Ostariophysi: Siluriformes: Pimelodidae)
Garavello, Julio Cesar;Shibatta, Oscar Akio;
Neotropical Ichthyology , 2007, DOI: 10.1590/S1679-62252007000300008
Abstract: a new species, pimelodus britskii, is described from the rio igua?u in the rio paraná drainage, on the border of paraná and santa catarina states, brazil. specimens of this species were wrongly included in the type series of pimelodus ortmanni. pimelodus britskii is distinguished from its congeners by color pattern, having circular dark brown blotches usually smaller than one orbital diameter, regularly and scattered along the trunk. differs from p. ortmanni by the following characters: body depth at posterior cleithral process greater than head length; lips not prominent; and maxillary barbel reaching or surpassing vertical drawn through median of adipose fin. pimelodus britskii represents the second species of the genus pimelodus from the rio igua?u basin.
New species of Trachycorystes Bleeker, with comments on other species of the genus (Ostariophysi: Siluriformes: Auchenipteridae)
Britski, Heraldo A.;Akama, Alberto;
Neotropical Ichthyology , 2011, DOI: 10.1590/S1679-62252011000200004
Abstract: a new species of trachycorystes from the rio aripuan?, above dardanelos and andorinhas falls, is described. the new species is distinguished from the only other species of the genus, t. trachycorystes, by the following characteristics: jaws of equal length (vs. lower jaw prognathous in t. trachycorystes); skull roof covered by thick (vs. thin) integument; inner mental barbel very thin and short not reaching base of outer barbel (vs. extending to or beyond base of outer mental barbel); dorsal-fin spine serrated posteriorly, smooth or rough anteriorly (vs. serrated anteriorly and smooth or rough posteriorly); caudal fin shallowly forked (vs. emarginate); and gas bladder simple, without diverticula (vs. with three posterior diverticula). comments and data on the nominal species trachycorystes trachycorystes are provided. trachycorystes cratensis miranda ribeiro, 1937, is allocated to the genus trachelyopterus valenciennes, 1840, and another local catfish species, parotocinclus aripuanensis garavello, 1988, has its type locality reassigned.
Pisces, Ostariophysi, Siluriformes, Auchenipteridae, Trachelyopterus lucenai Bertoletti, Pezzi da Silva and Pereira, 1995: historical occurrence and distribution extension  [PDF]
Artioli, L. G. S.,Maia, R.
Check List , 2010,
Abstract: The present note describes a historical occurrence and distribution extension of the species Trachelyopteruslucenai in coastal basins, state of Rio Grande do Sul, Brazil.
Ectoparasites as numerical dominant species in parasite community of Trachelyopterus striatulus (Siluriformes: Auchenipteridae) from Guandu River, southeastern Brazil
Mesquita, RLB.;Azevedo, RK.;Abdallah, VD.;Luque, JL.;
Brazilian Journal of Biology , 2011, DOI: 10.1590/S1519-69842011000400006
Abstract: sixty specimens of singing catfish trachelyopterus striatulus (steindachner, 1877) (siluriformes: auchenipteridae) collected from guandu river (22o 48' 32" s and 43o 37' 35" w), in the state of rio de janeiro, brazil from october 2006 to march 2009, were necropsied to study their parasites. from the 60 specimens of t. striatulus examined 57 were parasitised by at least one parasite species. the majority of the parasite specimens collected were monogeneans followed by nematoda, digenea and hirudinea. cosmetocleithrum sp. was the numerically predominant species with highest prevalence and abundance. the parasites of t. striatulus showed the typical pattern of aggregated distribution. no parasite species showed significant correlation between the body total length of the host and their abundance. the mean parasite species richness was not correlated with the host's total body length and sex. values of the brillouin index of diversity had a mean of h = 0.083 ± 0.136.
The role of chromosomal fusion in the karyotypic evolution of the genus Ageneiosus (Siluriformes: Auchenipteridae)  [cached]
Roberto Laridondo Lui,Daniel Rodrigues Blanco,Juliana de Fátima Martinez,Vladimir Pavan Margarido
Neotropical Ichthyology , 2013,
Abstract: Ageneiosus is the most widely distributed genus of the family Auchenipteridae among South American river basins. Although chromosome studies in the family are scarce, this genus has the largest number of analyzed species, with 2n = 54 to 56 chromosomes, differing from the rest of the family (2n = 58). This study aimed to analyze Ageneiosus inermis from the Araguaia River basin. The diploid number found was of 56 chromosomes. Heterochromatin was allocated in terminal region of most chromosomes, plus a pericentromeric heterochromatic block in pair 1, a pair distinguished by size in relation to other chromosomes pairs. AgNORs were detected in only one submetacentric chromosome pair, which was confirmed by FISH. 5S rDNA was present in only one metacentric chromosome pair. Hybridization with [TTAGGG]n sequence marked the telomeres of all chromosomes, in addition to an ITS in the proximal region of the short arm of pair 1. The repetitive [GATA]n sequence was dispersed, with preferential location in terminal region of the chromosomes. Ageneiosus has a genomic organization somewhat different when compared to other Auchenipteridae species. Evidences indicate that a chromosomal fusion originated the first metacentric chromosome pair in A. inermis, rearrangement which may be a basal event for the genus Ageneiosus é o gênero da família Auchenipteridae mais amplamente distribuído em bacias da América do Sul. Apesar dos estudos cromoss micos nesta família serem escassos, este gênero tem o maior número de espécies analisadas, com número diploide variando de 54 a 56 cromossomos, o que difere do restante da família (2n = 58). Este estudo objetivou analisar Ageneiosus inermis da bacia do rio Araguaia. O número diploide encontrado foi de 56 cromossomos. A heterocromatina se mostrou localizada na regi o terminal da maioria dos cromossomos, além de um bloco heterocromático pericentromérico no par 1, um par facilmente distinguível no cariótipo pelo seu maior tamanho quando comparado aos outros pares do complemento. AgRONs foram detectadas em somente um par de cromossomos submetacêntricos, que foi confirmado pela FISH. 5S rDNA se mostrou presente em somente um par de cromossomos metacêntricos. A hibridiza o com a sequência [TTAGGG]n marcou os tel meros de todos os cromossomos, além de um ITS (sequência telomérica intersticial) na regi o proximal do bra o curto do par 1. A sequência repetitiva [GATA]n se mostrou dispersa, com localiza o preferencial na regi o terminal dos cromossomos. Ageneiosus apresenta uma organiza o gen mica um pouco diferente quando comparada a outras
Dimorfismo sexual em Siluriformes e Gymnotiformes (Ostariophysi) da Amaz?nia
Py-Daniel, Lúcia H. Rapp;Fernandes, Cristina Cox;
Acta Amazonica , 2005, DOI: 10.1590/S0044-59672005000100015
Abstract: the present paper aims to summarize cases of sexual dimorphism in siluriformes and gymnotiformes. this summary focuses on neotropical representatives, with emphasis on amazonian fish. fishes from this region exhibit high species-level diversity, although the intraspecific limits of many of these forms are unknown. in loricariidae (siluriformes), mapping of dimorphic traits on cladograms has helped to demonstrate that patterns of sex dimorphism are consistent with hypotheses of monophyly, thus reinforcing its role as an important evolutionary phenomenon. in apteronotidae (gymnotiformes), mapping of characters on phylogenetic trees suggests that sexual dimorphism (regarding snout size, form, and presence/absence of teeth) has evolved independently in multiple taxa. recently in gymnotiformes, detected taxonomic errors are attributed to extreme differences between males and females in their morphology.
The cascudos of the genus Hypostomus Lacépède (Ostariophysi: Loricariidae) from the rio Igua?u basin
Garavello, Julio César;Britski, Heraldo Ant?nio;Zawadzki, Claudio Henrique;
Neotropical Ichthyology , 2012, DOI: 10.1590/S1679-62252012000200005
Abstract: we reviewed several large collections of the genus hypostomus from the rio igua?u basin summing up to 793 specimens mainly from the laboratório de ictiologia do departamento de ecologia e biologia evolutiva from universidade federal de s?o carlos, from fish collection of núcleo de pesquisas em limnologia, ictiologia e aquicultura da universidade estadual de maringá, and from the museu de história natural do cap?o da imbuia. hypostomus albopunctatus, h. commersoni, h. derbyi, and h. myersi are redescribed and hypostomus nigropunctatus is described as a new species. a practical key for identification of hypostomus species from the rio igua?u is also provided.
Bioacoustic variation of swimbladder disturbance sounds in Neotropical doradoid catfishes (Siluriformes: Doradidae, Auchenipteridae): Potential morphological correlates  [cached]
Ingrid M. KAATZ, Donald J. STEWART
Current Zoology , 2012,
Abstract: Swimbladder disturbance sounds of doradoid catfishes (Doradidae and Auchenipteridae) demonstrated striking waveform and spectrographic variation. We surveyed sounds of 25 doradoid species in 20 genera comparing these to sounds of four vocal outgroup catfish families. Sounds were either continuous waveforms (lacking interpulses) or pulsed (groups of pulses repeated at fixed temporal intervals). This is the first evidence for swimbladder calls with fixed interpulse patterns in catfishes. Vocal mechanism components that were similar between doradids and auchenipterids included: swimbladder shape, swimbladder dimensions and sonic muscle-somatic index. Morphological traits that showed variation among taxa and were evaluated for potential correlates of call diversity are: 1) diverticula (marginal outpocketings of the swimbladder with no connection to inner ear) and 2) elastic spring apparatus Müllerian rami (ESA-Mr). Within the doradid subfamilies and within the Auchenipteridae most species differed significantly in dominant frequency with frequency ranges overlapping to some extent for most. Doradid swimbladder diverticula did not explain dominant frequency variation within the doradoid superfamily. Some doradids with conical ESA-Mr had the highest dominant frequency sounds. Auchenipterids included both relatively lower and higher dominant frequency sound producers but lacked diverticula and had discoidal ESA-Mr. Comparing a phylogeny of doradoid genera with outgroup taxa, we infer that complex diverticula and conical ESA-Mr are derived characters within the Doradidae. Species representing outgroup families produced either continuous lower dominant frequency sounds (aspredinids, mochokids and pseudopimelodids) or pulsed higher dominant frequency sounds (pimelodids) [Current Zoology 58 (1): 171–188, 2012].
Astyanax jordanensis (Ostariophysi: Characidae), a new species from the rio Igua?u basin, Paraná, Brazil
Alcaraz, Héctor S. Vera;Pavanelli, Carla S.;Bertaco, Vinicius A.;
Neotropical Ichthyology , 2009, DOI: 10.1590/S1679-62252009000200008
Abstract: astyanax jordanensis, new species, is described from the rio jacu and rio das torres, both tributaries to the lower rio jord?o, in the rio igua?u basin, paraná, brazil. the new species is a member of the a. scabripinnis species complex. astyanax jordanensis differs from its congeners by several meristic and morphometric characters. mature males possess bony hooks in the dorsal, pectoral, pelvic, and anal fins, and mature females have a few small bony hooks on the first rays of the anal fin. the presence of these bony hooks in females and the endemism of the ichthyofauna in the rio jord?o are discussed.
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