| 1973. | Acteocina (Decorifer) delicatula (A. Adams, 1862) Oyama, K. 1973 p. 70, pl. 19, fig. 27a-c |
| 1954. | Decorifer delicatulus (A. Adams) Taki, I. & Oyama, K. 1954 pl. 21, fig. 7, 7a |
| 1922. | Retusa truncata Yamakawa Yokoyama, M. 1922a p. 25, pl. 1, fig. 7, 7a |
| Condition: | Present |
| Taxonomy: | Mollusca: Gastropoda: Scaphandridae: |
| Geologic Time: | Cenozoic: Pleistocene: |
| Horizon: | Imba Group: |
| Locality: | Chiba: Narita: Otake: |
| 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) |
| 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) |
  |
| Ichikawa, T., 1983, no. 9, p. 131. |
| Ichikawa, T., 1983, no. 9, p. 199. |
| Ichikawa, T., 1983, no. 9, p. 269. |
