A molecular and conchological dissection of the “scaly” Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae)

Abstract

The Bornean hydrocenids have so far been understudied compared to other non-pulmonate snails in this region. In the present study, we review a first group of minute land snail species belonging to the genusGeorissa(Gastropoda, Hydrocenidae) from Malaysian Borneo. This group is restricted to the species with conspicuous scale-like sculpture on the shell. Based on materials from recent fieldwork, museums, and personal collections, Malaysian Borneo hydrocenids are more complex and diverse in shell characters than previously anticipated. Here, a molecular, conchological, and biogeographic study of this “scaly group” is presented. We recognise 13 species of which six are new to science, namelyGeorissaanyiensissp. n.,Georissamuluensissp. n.,Georissabauensissp. n.,Georissasilaburensissp. n.,Georissakinabatanganensissp. n., andGeorissasepulutensissp. n.