Supernumerary chromosomes in a Rhamdia hilarii population (Pisces,Pimelodidae) |
| |
Authors: | A S Fenocchio L A C Bertollo |
| |
Institution: | (1) Universidad Nacional de Missiones, Argentina;(2) Departmento de Ciências Biológicas, Universidade Federal de São Carlos, Cx.Postal 676, 13.560 São Paulo, Brasil |
| |
Abstract: | A study was conducted on the chromosomes of a Rhamdia hilarii (Pisces, Pimelodidae) population. The results suggest that the basic chromosome number is 2n=58, with numerical variation up to a limit of 2n=63, due to the presence of supernumerary chromosomes which seem to be mitotically stable. These chromosomes are metacentrics and can be different in size. The C-banding pattern, showing heterochromatin especially in both telomeric regions, permits their identification in the karyotype. The NORs are located on secondary terminal constrictions on the short arm of a pair of subtelocentric chromosomes. However, there may be heteromorphism in the size of the secondary constrictions and, consequently, in the size of the NORs. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|