Pogoda P. & A. Kupfer

Sexual shape dimorphism in the cranium and pelvic girdle of Northern spectacled salamanders, Salamandrina perspicillata, investigated via 3D geometric morphometrics. pp. 113-122 plus Supplementary document.

Abstract. Sexual shape dimorphism (SShD) is still a neglected research topic, likely because SShD is often very subtle. Since shape differences between the sexes are difficult to detect by applying traditional morphometrics, only recently-emerged morphometric methodologies such as geometric morphometrics (GM) have highlighted their significance in evolutionary and morphology research. Here we provide an analysis of a three-dimensional morphometric data set of the cranial and, for the first time in a salamander, pelvic osteology of the small terrestrial spectacled salamander Salamandrina perspicillata. We also compare our GM results with prior results achieved via traditional linear morphometrics on the same species. Male and female salamanders differed both in cranial and pelvic girdle shape but not in absolute size. The shape but not size differences revealed by GM were congruent with the traditional morphometrics. We discuss intersexual shape differences in an evolutionary context and compare the features of both methods.

Key words. Amphibia, Caudata, Salamandridae, sexual dimorphism, sexual selection, osteology, allometry, morphology, traditional morphometrics.