Postembryonic Development of Cladocera Males of the Family Podonidae Mordukhai-Boltovskoi, 1968 (Cladocera, Onychopoda)

Abstract

The postembryonic development of males of marine Cladocera (Crustacea) of the family Podonidae was studied for the first time, based on two common species from the White Sea, Evadne nordmanni Loven 1836 and Pleopis polyphemoides (Leuckart 1859). The development of podonid males includes two juvenile stages which differ in the size of the testes, the shape and size of the penis, and the morphology of the copulatory hook on the distal segment of the endopodite of thoracic limb I. The females of Podonidae are pedogenetic and lack juvenile stages. Males of Podonidae retain the plesiomorphic postembryonal development, suggesting different rates of evolution in both sexes in this family.