著者

Keiji Matsuoka Takahiro Hirano

出版者

The Plankton Society of Japan, The Japanese Association of Benthology

雑誌

Plankton and Benthos Research (ISSN:18808247)

巻号頁・発行日

vol.15, no.3, pp.232-237, 2020-08-14 (Released:2020-08-04)

参考文献数

25

被引用文献数

1

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A new species of viviparid gastropod belonging to the genus Heterogen Annandale, 1921, is described from the Pleistocene Katata Formation of the Kobiwako Group in the southern part of Lake Biwa, central Japan. This new species is continuously recorded from the Nijigaoka Clays (1.2 Ma) to the Hiraen Clays (0.8 Ma) of the Katata Formation. This new species, Heterogen praelongispira sp. nov. is similar to the extant H. longispira in Lake Biwa, but the details of shell morphology are different from those of H. longispira, including fine-to-deep suture, flattened whorl side, and oval shape of embryonic shell.