The neritid snails of Brunei Darussalam: their geographical, ecological and conservation significance

Neritid snails are diverse and conspicuous in tropical coastal environments. They can serve as indicators of environmental change and can provide conservation information. In the present review of the neritid species of Brunei Darussalam, we report sixteen species, including seven new records from estuarine, mangrove and rocky-shore habitats. These records update distributions across the Central Indo-Pacific realm, specifically the Palawan/North Borneo ecoregion. Under-sampling, species misidentifications and locally-rare species undermine the accuracy of records in previous studies for the region. Three of the rocky-shore and two of the mangrove species collected here are represented by single specimens; these rocky-shore species are possible colonizers from neighbouring regions and the scarcity of the mangrove species likely refers to under-sampling. We present novel shell characteristics that readily distinguish between Neripteron violaceum and Nerip. cornucopia. We describe the ecology and habitat use of the Brunei species and discuss conservation issues.