Cipangopaludina crassibuca (Sarasin & Sarasin, 1898)

(Figs 2P, 3P, 6P)

Vivipara crassibuca Sarasin & Sarasin, 1898: 60, figs 120, 131, 132 (Lake Poso, Central Sulawesi, Indonesia).

Cipangopaludina crassibuca —Prashad, 1928: 176.

Idiopoma crassibucca —Schuh et al., 2010: https://www.discoverlife. org/mp/20q?search= Idiopoma+crassibucca .

Remarks: Vivipara crassibuca Sarasin & Sarasin, 1898 has been rarely mentioned after its description. Prashad (1928) regarded it as undoubtedly belonging to Cipangopaludina based on shell morphology. Schuh et al. (2010) assigned this species to Idiopoma in their online database but provided no justification. Here, we assign it to Cipangopaludina based on its shell morphology and the fact that its operculum exhibits the generic characters of Cipangopaludina . The operculum of C. crassibuca has denser growth lamellae compared to the other two species of Cipangopaludina examined. In addition, the convex inner margin of the first species is not as pronounced as in the other two species.