Cassidula plecotrematoides japonica occurs in Japan and it is critically endangered and endangered (CR+EN) there.[1]
The conservation status of Cassidula plecotrematoides plecotrematoides is near threatened.[2]
References
^"シイノミミミガイ" [Cassidula plecotrematoides japonica] (in Japanese). 2006. Archived from the original on 2012-02-23. Retrieved 2017-05-28.
^"ヒゲマキシイノミミミガイ" [Cassidula plecotrematoides plectrematoides] (in Japanese). 2006. Archived from the original on 2012-02-23. Retrieved 2017-05-28.
Martins, A. M. d. F. 1998. The anatomy of Cassidula Ferussac, 1821 and a case for the revival of the Cassidulinae Odhner, 1925. In: Morton, B. (ed.) The Marine Biology of the South China Sea. Proceedings of the Third International Conference on the Marine Biology of the South China Sea, Hong Kong. pp. 25–42