Cyclocypris diebeli Absolon, 1973 (Ostracoda,Crustacea), extinct in Europe,extant in Japan

Fossil Cyclocypris diebeli Absolon, 1973 Absolon, A. 1973. Ostracoden aus einigen Profilen spät- und postglazialer Karbonatablagerungen in Mitteleuropa,. Mitteilungen der Bayerischen Staatssammlung für Paläontologie und Historische Geologie, 13: 47–94.  Google Scholar] from Europe are redescribed, utilizing material with chitinous preservation of the appendages and carapace. These are compared with living C. diebeli from Kushiro Marsh, Hokkaido, Japan, representing the first living population of this species ever found. The fossil material is associated with strongly calcareous sediments, whereas the living material is found in weakly calcareous to acidic waters. Reasons for the different ecological requirements are discussed. Detailed study of soft parts of both living and fossil material using SEM is compared with other Cyclocypris species and it is shown that C. diebeli is more closely related to the North American Cyclocypris cruciata Furtos, 1935 Furtos, N. C. 1935. Fresh-water Ostracoda from Massachusetts,. Journal of the Washington Academy of Sciences, 25: 530–544.  Google Scholar] than to any European congeneric species. Furthermore, the comparison with other Cyclocypris species with left>right valve overlap results in the conclusion that the subgenus Laevicypris Krsti?, 1995 Krsti? N 1995 A new Cyclocypris subgenus—Laevicypris, in J. Ríha (ed.) Ostracoda and Biostratigraphy. Proceedings of the 12th International Symposium on Ostracoda (Rotterdam: A. Balkema), pp.?37–42  Google Scholar] is not a useful division of the genus.