Rhizorus acutaeformis (Yokoyama, 1922)
| 1973. | Rhizorus acutaeformis (Yokoyama, 1922) Lectotype Oyama, K. 1973 p. 69, pl. 19, fig. 19a, b |
| 1964. | Rhizorus acutaeformis (Yokoyama) Syntype Shikama, T. 1964 p. 116, pl. 35, fig. 6 |
| 1954. | Volvulella actaeformis (Yokoyama, 1922) Lectotype Taki, I. & Oyama, K. 1954 pl. 21, fig. 9 |
| 1922. | Volvula acutaeformis Yokoyama, 1922 Syntype Yokoyama, M. 1922a p. 26, pl. 1, fig. 9 |
| Condition: | Missing |
| Taxonomy: | Mollusca: Gastropoda: Diaphanidae: |
| Geologic Time: | Cenozoic: Pleistocene: |
| Horizon: | Imba Group: |
| Locality: | Chiba: Ichihara: Shito: |
| Oyama, K., 1973: Revision of Matajiro Yokoyama's type Mollusca from the Tertiary and Quaternary of the Kanto area. Palaeontological Society of Japan, Special Papers, no. 17, pp. 1–148, pls. 1–57. (Reference No. 0411) |
| Shikama, T., 1964a: Index fossils of Japan., pp. 1–287, pls. 1–80. Asakura Shoten, Tokyo. (in Japanese) (Reference No. 0618) |
| Taki, I. and Oyama, K., 1954: Matajiro Yokoyama's the Pliocene and later faunas from the Kwanto region in Japan. Palaeontological Society of Japan, Special Papers, no. 2, pp. 1–68, pls. 1–49. (Reference No. 0441) |
| Yokoyama, M., 1922a: Fossils from the upper Musashino of Kazusa and Shimosa. Journal of the College of Science, Imperial University of Tokyo, vol. 44, art. 1, pp. 1–200 + i–viii, pls. 1–17. (Reference No. 0465) |
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| Ichikawa, T., 1983, no. 9, p. 131. |
| Ichikawa, T., 1988, no. 15, p. 172. |
| Ichikawa, T., 1983, no. 9, p. 199. |
| Ichikawa, T., 1983, no. 9, p. 269. |
