Multiple Sex Chromosomes in the Genus Hoplias (Pisces: Erythrinidae)

Abstract

Cytogenetic studies were made in two populations of Hoplias sp. (Pisces, Ery-thrinidae) from the Lobo Reservoir, State of São Paulo, Brazil, and from the Ari-puanä River, State of Mato Grosso, Brazil. The two populations show evidences of multiple sex chromosomes. The animals from the Lobo Reservoir has an X1X1X2/X1X2Y mechanism, and those from the Aripuanã River an XX/XY1Y2 mechanism, this representing the first such case described for fishes. © 1983, Japan Mendel Society, International Society of Cytology. All rights reserved.