Bulletin of the Mizunami Fossil Museum

Monograph of the Mizunami Fossil Museum No. 7

Previously reported and new data on the occurrence of pteropods from the Cenozoic of Japan are summarized. Three generalized pteropod faunae which are faunally separate from one another are recognized in it. They are the Yatsuo, Amatsu and Recent warm-water pteropod faunae in chronologic order. The first is characterized by the predominance of the genus Vaginella. Cuvierina cf. tubulata 2 and Cavolinia bisulcala are the principal constituents of the second. The third consists of living taxa found in modern warm waters. The development of the Japanese Cenozoic pteropod fauna is represented as follows by use of these faunae: the N 8 zone to the N10 zone; the Yatsuo pteropod fauna, the N11 zone to the N13 zone; the transition period of the Yatsuo and Amatsu pteropod faunae, the N14 zone to the N 17 zone; the Amatsu pteropod fauna, the N18 zone to the N21 zone; the transition period of the Amatsu and Recent warm-water pteropod faunae and the N22 zone; the Recent warm-water pteropod fauna. The Yatsuo and Amatsu pteropod faunae contain numbers of taxa known only from Japan.

The phylogeny of Japanese Cenozoic taxa of the genus Cavolinia is discussed.