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Dieta de Hatcheria macraei (Girard, 1855) (Teleostei, Siluriformes, Trichomycteridae) en el río Chubut, Argentina
Ferriz,Ricardo A;
Latin american journal of aquatic research , 2012,
Abstract: a study of the diet of hatcheria macraei caught in chubut river, bajada del cóndor (43°31'21,12''s; 69°06'22,1''w) was performed in april 2000. the feeding regime of this trichomycteridae agreed with the carnivorous bentophagous type, and the dominant preys of both adults and juveniles were chironomid larvae, tricopter larvae, and cladocerans. the adult specimens exhibited a more diverse diet than the juveniles.
Dieta de Hatcheria macraei (Girard, 1855) (Teleostei, Siluriformes, Trichomycteridae) en el río Chubut, Argentina Diet of Hatcheria macraei (Girard, 1855) (Teleostei, Siluriforms, Trichomycteridae) in the Chubut River, Argentina
Ricardo A Ferriz
Latin american journal of aquatic research , 2012,
Abstract: Se realizó un estudio sobre la dieta de Hatcheria macraei capturados en el río Chubut, Bajada del Cóndor (43°31'21,12''S, 69°06'22,1''W), en abril 2000. El régimen alimentario de este tricomictérido correspondió al tipo carnívoro bentófago y las presas dominantes, tanto en juveniles como en adultos, fueron larvas de chironómidos, larvas de tricópteros y cladóceros. Los ejemplares adultos presentaron una mayor diversidad en la dieta que los juveniles. A study of the diet of Hatcheria macraei caught in Chubut River, Bajada del Cóndor (43°31'21,12''S; 69°06'22,1''W) was performed in April 2000. The feeding regime of this Trichomycteridae agreed with the carnivorous bentophagous type, and the dominant preys of both adults and juveniles were chironomid larvae, tricopter larvae, and cladocerans. The adult specimens exhibited a more diverse diet than the juveniles.
Karyotype description of five species of Trichomycterus (Teleostei: Siluriformes: Trichomycteridae)
Sato, Luciana Ramos;Oliveira, Claudio;Foresti, Fausto;
Genetics and Molecular Biology , 2004, DOI: 10.1590/S1415-47572004000100008
Abstract: trichomycteridae is a family of small catfish which are widely distributed throughout southern central america and south america. the present study showed that the cis-andean species trichomycterus florensis, trichomycterus sp. aff. trichomycterus itatiyae, trichomycterus reinhardti, trichomycterus davisi and trichomycterus auroguttatus had 2n = 54 chromosomes (42 metacentric, 10 submetacentric and 2 subtelocentric), with t. reinhardti, t. auroguttatus and t. sp. aff. t. itatiyae exhibiting only one chromosome pair with silver-stained nucleolus organizer regions (nors). the cytogenetic data suggest the existence of at least two groups of species in the cis-andean representatives of the genus trichomycterus. in the first group the first metacentric pair is considerably larger than the second metacentric pair and the nors occur in the pericentromeric position of the short arm of a large submetacentric pair while in the second group the first and second metacentric pairs are about the same size and larger than the other metacentric pairs and the nors are located in the pericentromeric position of the long arm of a large metacentric pair. the relative conservatism of the karyotype of the cis-andean trichomycterus species contrasts with the wide diversification observed in the trans-andean species, reinforcing the hypothesis that the genus is not monophyletic.
Karyotype description of five species of Trichomycterus (Teleostei: Siluriformes: Trichomycteridae)
Sato Luciana Ramos,Oliveira Claudio,Foresti Fausto
Genetics and Molecular Biology , 2004,
Abstract: Trichomycteridae is a family of small catfish which are widely distributed throughout Southern Central America and South America. The present study showed that the cis-Andean species Trichomycterus florensis, Trichomycterus sp. aff. Trichomycterus itatiyae, Trichomycterus reinhardti, Trichomycterus davisi and Trichomycterus auroguttatus had 2n = 54 chromosomes (42 metacentric, 10 submetacentric and 2 subtelocentric), with T. reinhardti, T. auroguttatus and T. sp. aff. T. itatiyae exhibiting only one chromosome pair with silver-stained nucleolus organizer regions (NORs). The cytogenetic data suggest the existence of at least two groups of species in the cis-Andean representatives of the genus Trichomycterus. In the first group the first metacentric pair is considerably larger than the second metacentric pair and the NORs occur in the pericentromeric position of the short arm of a large submetacentric pair while in the second group the first and second metacentric pairs are about the same size and larger than the other metacentric pairs and the NORs are located in the pericentromeric position of the long arm of a large metacentric pair. The relative conservatism of the karyotype of the cis-Andean Trichomycterus species contrasts with the wide diversification observed in the trans-Andean species, reinforcing the hypothesis that the genus is not monophyletic.
Trichomycterus igobi, a new catfish species from the rio Igua?u drainage: the largest head in Trichomycteridae (Siluriformes: Trichomycteridae)
Wosiacki, Wolmar B.;Pinna, Mário de;
Neotropical Ichthyology , 2008, DOI: 10.1590/S1679-62252008000100003
Abstract: a new species of trichomycterus is described for the rio igua?u drainage in southern brazil. trichomycterus igobi, new species, is readily distinguishable from all other species currently in the genus by its extremely large head (23.8-26.8 % sl), which is proportionally the largest head in any trichomycteridae. that characteristic plus the relatively deep body result in a very short-bodied overall aspect, the most extremely such case in the genus trichomycterus. other diagnostic features that distinguish the new species from most or all of its congeners include a short caudal peduncle (15.4-19.7 % sl); an almost entirely cartilaginous second hypobranchial (with only vestigial ossification); a mesial expanded palatine ossification; a narrow cleithrum, falciform in shape; and the lack of a proximal posterior concavity on the third ceratobranchial. the new species seems to form a monophyletic group with t. stawiarski and other undescribed species (t. sp. c), also endemic to the rio igua?u. as putative synapomorphies, the three species share a rigid spine-like morphology of individual procurrent caudal-fin rays, an extended area of dorsal caudal-fin procurrent rays, and numerous branchiostegal rays (ten or eleven).
Primer registro fósil de la familia Trichomycteridae (Teleostei: Siluriformes; Plioceno) en la Formación Monte Hermoso, Argentina First fossil record for the family Trichomycteridae (Teleostei: Siluriformes; Pliocene) in the Monte Hermoso Formation, Argentina  [cached]
Sergio Bogan,Federico L. Agnolin
Revista del Museo Argentino de Ciencias Naturales , 2009,
Abstract: En la presente nota se describen materiales asignables a la familia de Siluriformes Trichomycteridae, los cuales exhiben una serie de caracteres osteológicos que permiten referirlos a la subfamilia Trichomycterinae. Estos elementos consisten en un opercular e interopercular pertenecientes a un mismo individuo, procedentes del Plioceno Inferior-Medio de la Formación Monte Hermoso en la localidad de Farola de Monte Hermoso, provincia de Buenos Aires, Argentina. Este registro constituye el primer fósil reportado para la familia y unos de los pocos restos paleoictiológicos citados para la Formación Monte Hermoso. Some fossil remains referable to the siluriform family Trichomycteridae are described in this paper. These specimens exhibit a combination of characters that allow to include them within the subfamily Trichomycterinae. These elements consist on an opercular and interopercular of the same individual, collected in Lower-Middle Pliocene beds of the Monte Hermoso Formation, at the Farola de Monte Hermoso locality, Buenos Aires province, Argentina. This record constitutes the first fossil remains reported for the family, and one of the few paleoichthyological records for the Monte Hermoso Formation.
A new species of Trichogenes from the rio Itapemirim drainage, southeastern Brazil, with comments on the monophyly of the genus (Siluriformes: Trichomycteridae)
Pinna, Mário C. C. de;Helmer, José Luiz;Britski, Heraldo A.;Nunes, Leandro Rodrigues;
Neotropical Ichthyology , 2010, DOI: 10.1590/S1679-62252010000400002
Abstract: a new species of the formerly monotypic genus trichogenes is described from a high-altitude stream of the rio itapemirim system, an isolated atlantic drainage in the state of espírito santo, southeastern brazil. trichogenes claviger, new species, differs from all other trichomycterids by the sexually dimorphic posterior process of the opercle, much elongated in males; the terminal mouth; the deeply bifurcated anterior neural spines and the presence of a large anterodorsal claw-like process on the neural arches of the anterior four free vertebrae. the new species also differs from its only congener, t. longipinnis, by a number of additional traits, including the the lack of branched anal-fin rays in specimens of any size; the broader than long posterior nostril; the deeper head (head depth 72.9-86.6% hl); the presence of a fine dark line along the base of the anal fin; the lack of dark spots on cheeks; the shape of the interopercle; the presence of odontodes on a bony expansion on the posterodorsal margin of the interopercle; the fewer vertebrae (35); the absence of an antorbital; and the fewer pleural ribs (eight). small juveniles of the new species are also strikingly different from those of all other trichomycteridae, including t. longipinnis, having a very large lateral eye, an upturned mouth, and compressed head. trichogenes claviger occurs in shaded sectors of a blackwater sluggish stream with sandy substrate and patchy accumulations of vegetable debris, a habitat markedly different from the rocky torrential environment known for t. longipinnis. a comparison of the internal anatomy of the two species provides the basis for a hypothesis of a monophyletic trichogenes. data from the new species further support a sister-group relationship between trichogeninae and copionodontinae, as well as the position of that clade as sister group to all remaining trichomycteridae.
Dorsolateral head muscles of the catfish families Nematogenyidae and Trichomycteridae (Siluriformes: Loricarioidei): comparative anatomy and phylogenetic analysis
Datovo, Aléssio;Bockmann, Flávio Alicino;
Neotropical Ichthyology , 2010, DOI: 10.1590/S1679-62252010000200001
Abstract: the skeletal muscles of the dorsolateral region of the head of the nematogenyidae and representatives of the all major clades of the trichomycteridae are described and illustrated. a hypothesis on the phylogenetic relationships among these taxa exclusively based on the surveyed musculature is presented. the single most parsimonious cladogram obtained from the phylogenetic analysis of the 36 myological characters gathered and 35 terminal-taxa mostly agrees with the previous hypotheses of trichomycterid intrarelationships. the copionodontinae and trichogeninae form a monophyletic lineage that is the sister-group to all remaining trichomycterids. the monophyly of the clades formed by glanapteryginae plus sarcoglanidinae; stegophilinae plus tridentinae plus vandelliinae; and the assemblage comprising all of these five subfamilies (tsvsg clade) is corroborated. two of our findings are, however, discordant with the previous prevailing hypotheses: the sister-group relationship among tridentinae and stegophilinae and the monophyly of the trichomycterinae lato sensu, i. e., including the genera scleronema and ituglanis. in addition, the previously proposed osteological synapomorphies supporting the close affinities of scleronema and ituglanis with the tsvsg clade were revised, revealing that they are either invalid or ambiguous. most of the synapomorphies herein proposed are homoplasy-free, with some of them corroborating the monophyly of weakly-supported groups, such as stegophilinae.
Primer registro fósil de la familia Trichomycteridae (Teleostei: Siluriformes; Plioceno) en la Formación Monte Hermoso, Argentina
Bogan,Sergio; Agnolin,Federico L.;
Revista del Museo Argentino de Ciencias Naturales , 2009,
Abstract: some fossil remains referable to the siluriform family trichomycteridae are described in this paper. these specimens exhibit a combination of characters that allow to include them within the subfamily trichomycterinae. these elements consist on an opercular and interopercular of the same individual, collected in lower-middle pliocene beds of the monte hermoso formation, at the farola de monte hermoso locality, buenos aires province, argentina. this record constitutes the first fossil remains reported for the family, and one of the few paleoichthyological records for the monte hermoso formation.
Phototactic behaviour of subterranean Copionodontinae Pinna, 1992 catf ishes (Siluriformes, Trichomycteridae) from Chapada Diamantina, central Bahia, northeastern Brazil  [PDF]
Rantin Bianca,Bichuette Maria Elina
International Journal of Speleology , 2013,
Abstract: The phototactic behaviour of three Copionodontinae (Trichomycteridae) catf ish species (two troglobites and one epigean) from Chapada Diamantina was studied in order to detect modif ications related to isolation in the subterranean environment. Differences in response under different luminosities were detected and, unlike other cavef ish, Copionodontinae cave species have shown to be more photophobic than the epigean syntopic to them. The troglobitic Glaphyropoma spinosum is the most photophobic, presenting this behaviour under all light intensities, and more homogeneous regarding morphological characters. It suggests that this population is probably isolated for a longer time in the subterranean environment compared to Copionodon sp. n., the other cave species, which is only photophobic under low light intensities. The indifference to light exhibited by the epigean species C. pecten could be an answer to a recent predation pressure, an ecological aspect, and perhaps this character-state is under f ixation in this population. There are also evidences that the skin has a relevant role in the perception of light for the Copionodontinae species.
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