PARAKRITHELLA PSEUDADONTA (HANAI, 1959) IN THE INLAND SEA, JAPAN (OSTRACODA)

Abstract

Parakrithella pseudadonta (Hanai, 1959), discovered from some coasts of Japan by Hanai (1959) and Ishizaki (1968, '71), occurs abundantly in the Inland Sea. Both Hanai and Ishizaki have described its valves alone, but left its soft parts undescribed, therefore the species is to be redescribed wholly in this paper. The specimen from Japan named Eukrithe zhirmunskyi, gen. n., sp. n., by Schornikov (1975) is thought to be the A-1 instar of this species. The comparison between adults and A-1 instars may raise some questions about the development and phylogeny of this species and the systematic position of the genus to which it belongs. I express my thanks to Prof. A. Inaba of Hiroshima University for his valuable advice and help in collecting specimens.