Umbonium mysticum Yokoyama
| 1926. | Umbonium mysticum Yokoyama |
| Condition: | Missing |
| Taxonomy: | Mollusca: Gastropoda: Trochidae: |
| Geologic Time: | Cenozoic: |
| Yokoyama, M., 1926g: Tertiary Mollusca from southern Totomi. Journal of the Faculty of Science, Imperial University of Tokyo, Section 2, vol. 1, pt. 9, pp. 313–364, pls. 38–41. (Reference No. 0484) |
 |
| Ichikawa, T., 1983, no. 9, p. 337. |
