| 1973. | Modiolus (Modiolus) modiolus difficilis (Kuroda & Habe, 1950) Oyama, K. 1973 p. 81, pl. 27, fig. 8 |
| 1954. | Volsella (Volsella) difficilis Kuroda & Habe Taki, I. & Oyama, K. 1954 pl. 12, fig. 21 |
| 1920. | Modiola modiolus Linne Yokoyama, M. 1920 p. 145, pl. 11, fig. 21 |
| Condition: | Present |
| Taxonomy: | Mollusca: Bivalvia: Mytilidae: |
| Geologic Time: | Cenozoic: Pleistocene: |
| Horizon: | Miyata Formation: |
| Locality: | Kanagawa: Miura: Shimo-Miyata: |
| 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., 1920: Fossils from the Miura peninsula and its immediate north. Journal of the College of Science, Imperial University of Tokyo, vol. 39, art. 6, pp. 1–193, pls. 1–20. (Reference No. 0464) |
  |
| Ichikawa, T., 1983, no. 9, p. 127. |
| Ichikawa, T., 1983, no. 9, p. 195. |
| Ichikawa, T., 1983, no. 9, p. 259. |
