Cytogenetic studies on marine ostracods: the karyotype of Gigantocypris muelleri Skogsberg, 1920 (Ostracoda, Myodocopida)

Abstract. The chromosome complement of a bathypelagic myodocopid ostracod, Gigantocypris muelleri Skogsberg, 1920, is described. The karyotype of this bisexual species consists of 2n = 18 (16A + XX) for the female and 2n = 17 (16A + XO) for the male. These chromosomes are all metacentric and of very similar size, ranging from 19μm to 24μm. This is the first description of the karyotype of a marine ostracod.