MolluscaBase name details
original description
Takeda, H. (1953). The Poronai Formation (Oligocene Tertiary) of Hokkaido and south Sakhalin and its fossil fauna. <em>Hokkaido Association of Coal Mining Technologists, Studies on Coal Geology.</em> 3: 1-103, pls. 1-13.
page(s): 53 (partim) pl. 3, fig. 1,3,5,6 [details]