Re-evaluating Carinigera: Molecular data overturn the current classification within the clausiliid subfamily Alopiinae (Gastropoda, Pulmonata)

The current subdivision of the clausiliid subfamily Alopiinae relies for a large part on genital-anatomical characters. Based on a few such characters Carinigera is placed within the tribe Montenegrinini, whereas Isabellaria and Sericata are included within the tribe Medorini. This classification is unexpected on the basis of two observations: (1) Carinigera is conchologically indistinguishable from Sericata and highly similar to Isabellaria and (2) Carinigera, Isabellaria and Sericata have mosaic distributional patterns in central and northern Greece, which are difficult to explain given the low vagility of snails of these genera. The complete ITS1 and ITS2 and partial 18S rRNA, 5.8S rRNA and 28S rRNA sequences used in this study reveal that all Carinigera sensu auct. species are nested among Medorini, and should therefore be placed within that tribe. Apart from this, the results largely support the current higher classification of the Clausiliidae. Carinigera sensu auct. consists of at least two clades, which are not sister groups. Both are related to geographically close species hitherto classified with Sericata or Isabellaria. The two groups of Carinigera do not correspond to the alleged subgenera Angiticosta and Carinigera s.s. This study shows that, like conchological characters, the traditional diagnostic genital-anatomical characters used at tribe level suffer more often from homoplasy than previously thought. Therefore, classifications based on only a few such characters can be erroneous and should be mistrusted, especially when they conflict with both conchological and distributional patterns, as in Carinigera.