From depressed to detached: extreme shell shape variation in some Peruvian Bostryx species (Gastropoda: Bulimulidae)

This paper investigates Bostryx species from Peru, which show variation in shells shape and are partly carinated, using both ecological and molecular data. The study area is situated in a valley at the western side of the Andes, with a total length of 25 km and an altitudinal range of almost 1,140 m, but focuses on two localities: El Infernillo at ca. 3,350 m and Tambo de Viso at ca. 2,700 m. The morphological variation of the species presents a rather complex picture that cannot completely be resolved by ecological data alone. Molecular data points to three taxa, two of which are variable in shell shape and each restricted to one of the localities mentioned; the third taxon is constant in shell shape and occurs over a large range of the study area. The species originally described as Bostryx multiconspectus Breure, 2008 and B. primigenius Breure, 2008 are redefined as a result.