Cytotaxonomic diagnosis of Trichomycterus diabolus (Teleostei: Trichomycteridae) with comments about its evolutionary relationships with co-generic species
The karyotype and the Ag-NOR location of a sample of Trichomycterus diabolus collected in the córrego Hortelã (Botucatu, São Paulo, Brazil) are described. The species exhibited 2n=56 chromosomes (42 metacentrics, 12 submetacentrics and 2 subtelocentrics) and the nucleolus organizing region located n...
Main Authors: | , , |
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Format: | Article |
Language: | English |
Published: |
Sociedade Brasileira de Ictiologia
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Series: | Neotropical Ichthyology |
Subjects: | |
Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252004000300003&lng=en&tlng=en |
Summary: | The karyotype and the Ag-NOR location of a sample of Trichomycterus diabolus collected in the córrego Hortelã (Botucatu, São Paulo, Brazil) are described. The species exhibited 2n=56 chromosomes (42 metacentrics, 12 submetacentrics and 2 subtelocentrics) and the nucleolus organizing region located near to the centromere on the long arm of the largest metacentric pair. The presence of 2n=56 chromosomes in T. diabolus is an interesting characteristic since until now all cis-Andean species karyotyped presented 2n=54 chromosomes while almost all trans-Andean species presented different diploid numbers. The possible origin of this unexpected karyotypic form is discussed. |
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ISSN: | 1982-0224 |