original description
Yokoyama, M. (1920). Fossils from the Miura Peninsula and its immediate north. <em>Journal of the College of Science, Tokyo Imperial University.</em> 39(6): 1-193, 20 pls., available online at https://www.biodiversitylibrary.org/page/6959694
page(s): 73-74; pl. 4, figs 20a, b] [details]
additional source
Ichikawa, T. 1983. Catalogue of Type and Illustrated Specimens in the Department of Historical Geology and Palaeontology of the University Museum, University of Tokyo. Part 2. Cenozoic Fossils and Recent Specimens. University Museum, University of Tokyo Material Reports No. 9. iv + 536 pp.
page(s): 121 [details]
From editor or global species database
Type material Ichikawa (1983) list the type number of the holotype: CM20208. [details]
From editor or global species database