Karyological study of some cyprinid species from Ethiopia. The ploidy differences between large and small Barbus of Africa

Abstract

Chromosome sets of nine species of Barbus and a species of Varicorhinus from Ethiopia were investigated. All large Barbus (B. bynni, B. intermedius, B. ethiopicus) and V. beso are shown to have 2N =150, whereas all small Barbus (B. anema, B. kerstenii, B. paludinosus, and three unidentified (probably undescribed) species have 2N = 50. Based on the karyological data and on the published morphological data, an independent origin of small and large Barbus of Africa is suggested. The authors believe that large Barbus of Africa constitute a monophyletic group and that this group has no sister-group relationships with any of the small Barbus of Africa.