A revision of Bithyniidae (Mollusca, Gastropoda) from the Inle Lake Basin, Myanmar

Abstract

Inle Lake, located on the Shan Plateau of Myanmar, is the only ancient lake on the Indochinese Peninsula and a biodiversity hotspot of freshwater fauna with high diversity and endemism, including molluscs. However, recent research on its biodiversity remains limited. Based on morphological, anatomical, and molecular studies, we systematically revise the freshwater snails of the family Bithyniidae from the Inle Lake basin. We provide an updated re-description of four bithyniid species within three genera from the Inle Lake basin, including one new record, Digoniostoma iravadica comb. nov. The endemic genus Parabithynia syn. nov. with one endemic species of Inle Lake, Hydrobioides physcus comb. rev., is considered a synonym of Hydrobioides. Gabbia nana comb. nov. is assigned to Gabbia based on shell morphology and molecular phylogeny. Hydrobioides dautzenbergi stat. rev. from Thailand is recognised as a valid species rather than a synonym of Hydrobioides nassa, which is endemic to Shan State of Myanmar. There are altogether seven bithyniid species recorded from the Inle Lake basin and surrounding area, including four endemic species.