Ostrea gravitesta Yokoyama
| 1958. | Ostrea gravitesta Yokoyama Syntype Makiyama, J. 1958 pl. 57, fig. 2a-c |
| 1926. | Ostrea gravitesta Yokoyama, 1926 Syntype Yokoyama, M. 1926j p. 388, pl. 45, fig. 2a-c |
| Condition: | Missing |
| Taxonomy: | Mollusca: Bivalvia: Ostreidae: |
| Geologic Time: | Cenozoic: Miocene: |
| Makiyama, J., 1958: Matajiro Yokoyama's Tertiary fossils from various localities in Japan. Part 2. Palaeontological Society of Japan, Special Papers, no. 4, pp. 1–6, pls. 25–57. (Reference No. 0368) |
| Yokoyama, M., 1926j: Fossil Mollusca from the oil-fields of Akita. Journal of the Faculty of Science, Imperial University of Tokyo, Section 2, vol. 1, pt. 9, pp. 377–389, pls. 44–45. (Reference No. 0487) |
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| Ichikawa, T., 1983, no. 9, p. 58. |
| Ichikawa, T., 1983, no. 9, p. 342. |
