Umbonium naganumana Otuka, 1937
| 1937. | Umbonium naganumana Otuka, 1937 Holotype |
| 1930. | Umbonium giganteum naganumanum Otuka, 1930 Holotype Otuka, Y. 1930 p. 25, fig. 1a-c |
| Condition: | Present |
| Taxonomy: | Mollusca: Gastropoda: Trochidae: |
| Geologic Time: | Cenozoic: |
| Otuka, Y., 1930: A new variety of fossil Umbonium. Journal of the Geological Society of Tokyo, vol. 37, no. 436, pp. 25–26. (Reference No. 0381) |
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| Otuka, Y., 1937e: Geologic structure of the south Kwanto region, Japan. (1) (Yokohama-Huzisawa district). Bulletin of the Earthquake Research Institute, Tokyo Imperial University, vol. 15, pt. 4, pp. 974–1040, pls. 67–70. (in English with Japanese abstract) (Reference No. 0607) |
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| Ichikawa, T., 1988, no. 15, p. 124. |
| Ichikawa, T., 1983, no. 9, p. 75. |
