Cranial morphometric variation in some South American species of the genus Myotis (Kaup, 1829) (Vespertilionidae, Chiroptera)

MARCOS ISMAEL MOLLERACH; JUAN JOSÉ MARTÍNEZ; RUBÉN MARCOS BARQUEZ

Punta del Este

Congreso; 9th International Congress of Vertebrate Morphology; 2010

International Society of Vertebrate Morphologists

The genus Myotis is represented by 12 species in South America, many of them are endemic. Several studies have attempted to elucidate the systematic of the genus, but with different results, as a result the taxonomy of the group is far from be settled. In this work we present the first results from a geometric morphometric study based on 13 landmarks in the ventral region of the skull. We worked with 137 specimens of 8 species of the genus. The analysis of canonical variables of the 8 species revealed a high classification rate in three species M. chiloensis, M. levis, M. oxyotus, although these were represented by a low number of individuals, the rate was moderately high in M. dinelli and M. albescens, while in M. nigricans and M. riparius the rate was low. MANOVA revealed significant differences between M. dinelli and M. albescens, and between these and riparius-nigricans group, the last group was not significantly different. No allometric effect was observed in centroid size in the differentiation of species due to the shape of the skull. M. dinelli has a skull bigger than the species M. albescens, M. nigricans and M. riparius, which do not differ in size. We conclude that it is necessary to increase the number of individuals per species and analyze the variations in other areas of the skull in order to understand interspecific cranial variation in this complex group of bats.