Ontogeny of an anchialine ostracod from Western Australia and comments on the origin and distribution of Halocyprididae
Juvenile instars II, IV, and V of the anchialine halocyprid ostracod Danielopolina kornickeri Danielopol, Baltanas & Humphreys, 2000 (Thaumatocyprididae) are described and illustrated. In addition, a supplementary description of the adult male is presented. Specimens had been collected in Bundera Sinkhole, the type locality of the species in Western Australia. Also, juvenile instars I and II of the deep-sea species Thaumatoconcha radiata Kornicker & Sohn, 1976, which is in the same family as members of the genus Danielopolina, are described and illustrated. It is tentatively concluded that during its ontogeny, D. kornickeri has 6 growth stages; morphological characters useful in identifying the stage and sex of juveniles of D. kornickeri are presented. Finally, the hypothesis is proposed for an anchialine cave ancestor to the present-day planktonic Halocyprididae, now widely spread in the oceans.