Suzuki, K. 1941. A new naiad, Unio (Nippononaia) ryosekiana, n. subgen. and n. sp., from the Lower Cretaceous of Japan. Jour. Geol. Soc. Japan 48(575): 410-413.
Suzuki, 1941. Jour. Geol. Soc. Japan 48(575): 411.
(intro'd as sub-gen. of Unio Retzius, 1788)
Type species: Unio (Nippononaia) ryosekiana Suzuki, 1941 (orig. desig.) = Nippononaia ryosekiana
Suzuki, 1941. Jour. Geol. Soc. Japan 48(575): 412, text figs. 1-3.