Phreatic Catfish of the Genus Silvinichthys from Southern South America (Teleostei, Siluriformes, Trichomycteridae)

Autor(es)

Fernández, Luis ; Pinna, Mario C. C. de

• Tipo de documento: Artigo Científico
• Fonte: Copeia; n. 1, p. 100-108, Feb. 2005.
• Área do conhecimento: Ciências Biológicas - Genética
• Assunto(s): Peixes Silvinichthys

Resumo

The cytogenic analyses showed that P. mangurus has a diploid number of 2n=54 chromosomes (6M, 26SM, 12 ST and 10A), single Ag-NORs on the short arm of a middle-sized ST pair, identified as pair 19, and a very small amount of C-band positive segments in two chromosome pairs. The Ag-NORs are C-band positive. The staining of the chromosomes of P. mangurus with CMA3 reveled the occurrence of bright signals corresponding to the Ag-NORs segments, to the C-band positive segments and also to some C-band negative segments. The occurrence of a diploid number of 2n-54 in all species of the family Pseudopimelodidae and its absence among representatives of Pimelodidae and Heptapteridae, two previously considered related families, reinforces the hypothesis that Pseudopimelodidae is a monophyletic group. (AU)

• Processo FAPESP: 99/09781-6 - Morfologia das vértebras anteriores em Pristigasteroidea e suas implicações sobre as relações filogenéticas entre a Clupeomorpha e Ostariophysi (Osteichthyes, Teleostei)
• Beneficiário: Mario Cesar Cardoso de Pinna
• Modalidade de apoio: Auxílio à Pesquisa - Temático