Phylogenetic Position of the Genus Ridleyconcha (Gastropoda, Stylommatophora)

Abstract

: The Fernando de Noronha Archipelago off NE Brazil harbors a few unique terrestrial gastropod species. One of them, the mono-typic genus Ridleyconcha Christensen, 2020, presents such an idiosyncratic shell morphology that, in the 130 years since its description, it has been variously allocated in unrelated families: Streptaxidae, Endodontidae, Charopidae, Camaenidae, and Scolodontidae. Herein, R. quinque-lirata is included into a molecular phylogenetic framework of stylommatophoran land snails to clarify its taxonomic position. The analysis supports the latest morphological revision classifying Ridleyconcha in Scolodontidae. Considering the present sampling, Ridleyconcha appears to be the sister taxa of Entodina Ancey, 1887.