Intraspecific morphological and genetic variability in the European freshwater snail Radix labiata (Rossmaessler, 1835) (Gastropoda: Basommatophora: Lymnaeidae)

Radix labiata is a widely distributed Palaearctic freshwater snail. This work aims to improve the knowledge of the intraspecific variability in the most important characters used for its determination. To find out which characters are really suitable to distinguish this species from other similar Radix species an integrative approach was applied, involving morphological and molecular data.Molecular sequences of the nuclear spacer fragment ITS-2 and/or the mitochondrial gene fragment cyt-b were obtained from 26 individuals of R. labiata from different regions of Europe, including type localities of Limnaeus pereger labiatus. From the subsample of 24 specimens of which sequences of both gene fragments were available, the variability of several characters that are commonly used for species identification (shell morphology, mantle pigmentation, shape and position of the bursa copulatrix, length and position of the bursa duct, length ratio of praeputium to penial sheath) were measured or documented. Morp