On the verge of extinction – revision of a highly endangered Swiss alpine snail with description of a new genus, Raeticella gen. nov. (Gastropoda, Eupulmonata, Hygromiidae)

Abstract

The phylogenetic status of the alpine land snail Fruticicola biconica has remained questionable since it was described by Eder in 1917. Considered a microendemic species from mountain tops in Central Switzerland, the shell is specially adapted for life under stones. Herein, we show via molecular and anatomical investigations that F. biconica neither belongs to the land snail genus Trochulus, nor to any other genus within Trochulini, but rather warrants placement within the newly established genus Raeticella Kneubühler, Baggenstos & Neubert, 2022. Phylogenetic analyses reveal that R. biconica is clearly separated from Trochulus. These findings are supported by morphological investigations of the shell and genitalia.