Karyotypes in Two Species of the Solemyidae (Bivalvia, Cryptodonta)

Abstract

Karyotypes in Petrasma pusilla and Acharax japonicus of the family Solemyidae have been studied. In both species, chromosome numbers of 11(n) and 22(2n) were observed. The metaphase chromosome complement of P. pusilla consists of 5 pairs of metacentrics, 3 pairs of submetacentrics, 2 pairs of submeta- or metacentrics and 1 pair of subtelo- or submetacentrics. The metaphase chromosome complement of A. japonicus consists of 10 pairs of metacentrics and 1 pair of meta- or submetacentrics.