The well-known specialist of Central American and Caribbean land shells, Fred Thompson, recently published two interesting papers. Today I mention only his paper on Cerionidae (Thompson, 2011); the other paper will follow shortly.
Cerionids are well-known from the Caribbean, where they occur at low elevations. During his extensive field work in Mexico, Thompson found shells in habitats and elevations that were uncharacteristic for Cerion, and he put them as indeterminable “Urocoptidae”. Closer study, also of the anatomy, revealed that these shells should be classified with the family Cerionidae. In this paper three new species are described within a new genus, Mexistrophia. This genus is now known to be distributed in the Mexican states Querétaro, Nuevo León and Hidalgo, and may be quite widespread once anatomical data become available to ascertain their identification.
The type species is M. reticulata, type locality Edo. Querétano, 1.0 km E Pinal de Amoles, 2150 m. Holotype UF 211128.
A second species, M. obsoleta, was found at a nearby location, 15.8 km by road SW Pinal de Amoles, 2585 m. Holotype UF 34298.
Finally, a third species, M. inexpectata, is described from Edo. Nuevo León, 0.5 km N El Refugio, 2360 m. Holotype UF 226407.
All species are narrow-range endemics and inhabit cool temperate conifer forests that are subject to seasonal frosts.
Biogeographically, it is interesting that this group is disjunct from the ‘true’ Cerion, occurring in the West Indies.
Thompson, F.G., 2011. Mexistrophia, a new genus of Cerionidae from Mexico (Gastropoda: Pulmonata: Urocoptoidea). – The Nautilus 125: 182-192.