Diet and sexual dimorphism of Liophis poecilogyrus (Serpentes, Dipsadidae) from the wetland regions of Northeast Argentina

PRIETO Y.A., GIRAUDO A.R. AND LÓPEZ M.S.

JOURNAL OF HERPETOLOGY

SOC STUDY AMPHIBIANS REPTILES

Año: 2012 vol. 46 p. 402 - 406

0022-1511

Feeding ecology is one of the most important aspects in the life history of snakes; however, studies about their trophic ecology are scarce and sometimes inaccurate. Liophis poecylogyrus is a mid-sized snake widely distributed in South America and relatively abundant in the study area. We describe the diet and sexual dimorphism of L. poecilogyrus from northeast Argentina based on the examination of museum specimens and we compare our data with studies which include representative samples of this species. Amphibians were the most frequent prey (75%) and one reptile (1%) was found. Families represented were: Bufonidae (53%), Leiuperidae (19%), Leptodactylidae (14%), Hylidae (7%), Cyclorhamphidae (3%), Microhylidae (2%) and Gymnophtalmidae (2%). We observed that L. poecilogyrus has significant sexual size dimorphism in all morphometric characters analyzed, but not in scalation variables. Despite the fact that L. poecilogyrus is considered by some authors as an omni-carnivore, our data and other quantitative studies on distant populations from South America lead us to consider this species as having a strong tendency to include primarily anurans in its diet. The population studied has its own characteristics but retains similarities with geographically nearby and remote populations. It is a specialist species and its feeding habits seem to be conservative both in different populations of the same species and in phylogenetically-related species. Sexual size dimorphism may be a common feature of the taxonomic group.