Shape and habitat disparity in Palaeogene land snails (Stylommatophora, Orthalicoidea, Vidaliellidae) of southwestern Europe: two new bulimoid genera from the Palaeogene of Mallorca (Balearic Islands, western Mediterranean)

The vidaliellids were a family of gastropods with an abundant fossil record in Palaeogene rocks from southwestern Europe and north Africa. However, their palaeobiogeographic patterns of dispersal and their phylogeny are still not fully understood. In this paper, we revisit two gastropod species from the Palaeogene of Mallorca (Balearic Islands, western Mediterranean), which can be classified within the family Vidaliellidaes. Selvovum nov. gen. is described to contain the species “Ampullaria” selvensis, a large and ovoid vidaliellid that lived in the swamps and forests of the late Eocene of Mallorca. Calculocochlea oliveri nov. gen. nov. sp. is described for another, medium-sized land snail that thrived among the riverine forests and bushlands of the early Oligocene of Mallorca. Relationships of this latter taxon with the Vidaliellidae remain contentious because of its particular ornamentation and its lack of a reflected peristome. These two new taxa suggest high habitat diversity for the Vidaliellidae, and they show that Mallorca was a refugium for vidaliellids, which became extinct in the Iberian Peninsula and southern France towards the end of the middle Eocene.