Evidence for heteromorphic sex chromosomes in male amphibians (Anura: Leptodactylidae).

In Eupsophus migueli, an anuran species endemic to southern Chile, all males examined have a heteromorphic pair of chromosomes, a small metacentric and a telocentric of the same size. In females, the corresponding pair, No. 14, is telocentric. This suggests that this species has an XX/XY system of sex chromosomes. The male is the heterogametic sex.