Three new non-lacustrine species of the endemic freshwater gastropod genus Sulawesidrobia (Caenogastropoda, Truncatelloidea, Tateidae) from Sulawesi, Indonesia, with additional records of species from ancient Lake Poso

The vast majority of freshwater gastropods of the family Tateidae dwell in springs, small streams and the groundwater. In Sulawesi, however, all 31 described species occur in lake habitats. This exclusivity is certainly an artefact, a consequence of the lack of research in non-lacustrine habitats.

Indeed, recent explorations discovered three species in non-lacustrine habitats, Sulawesidrobia lasoloensis sp. nov. and S. marmer sp. nov. in small streams in Southeast Sulawesi, and S. tilangaensis sp. nov. in the spring-fed Tilanga natural pool in South Sulawesi. We describe these species based on shell morphology, anatomy as well as mitochondrial sequence data and, based on the latter, inferred their phylogenetic relationships.

These analyses also included new samples from Lake Poso. Sulawesidrobia lasoloensis sp. nov. and S. marmer sp. nov. formed a sister group to a clade from the Malili-Lake system, whereas S. tilangaensis sp. nov. was nested among the species from Lake Poso. Considering the long branches as well as the geographic distances between the new species and their respective lake relatives as well as the large unexplored areas, many more species dwelling in similar, for tateids more typical habitats are to be expected.