An undescribed genus and species of Geomitridae (Gastropoda: Helicacea) from peridotite hills in Málaga Province, Spain

A hitherto unknown species of the family Geomitridae was discovered in 2014 on the Sierra Bermeja (Prov. Málaga, Spain). Subsequent searches in the same Province have revealed its presence at seven localities on this and other peridotite hills, but none on areas with other rock types. Its shell characters are unremarkable for a geomitrid, resembling those e.g. of Helicella. However, anatomical study has revealed that it has sufficiently distinctive genital anatomy for description of a new genus to be necessary. In particular, the presence of two very small vaginal appendages in the position usually occupied by (larger) dart sacs, combined with the right ommatophore retractor muscle following a course free of the distal genitalia gives a combination unique in the Geomitridae. Also, the vas deferens is unusually stout. Hence, this paper names it as Peridotitea bermejensis gen. et sp. nov., discusses its affinities, and presents an account of what is known of its distribution, status and ecology.