Phylogenetic Relationships of Old World Ratsnakes Based on Visceral Organ Topography, Osteology, and Allozyme Variation

Abstract

Phylogenetic relationships of thirty species and subspecies of Old World ratsnakes (genera Elaphe auct. and Gonyosoma Wagler) are estimated using visceral topography, vertebrae, and allozyme variation. Distances between the taxa were calculated from positions and lengths of visceral organs, frequencies of qualitative characteristics and lengths of vertebrae, and frequencies of proteins encoded by 19 gene loci. The Indo-Malayan species group with conservative features has large phylogenetic distances to the Euro-Mediterranean and Siberian and to the East and High Asian species. The latter cluster exhibits parallel evolution with species from the Euro-Mediterranean and Siberian region. The East Asian Elaphe rufodorsata and the Mediterranean Elaphe scalaris show derived features and large distances to related taxa. This study represents a step towards a definitive reconstruction of phylogenetic relationships within Old World Elaphe species. Taxonomic changes include the revalidation of Coelognathus Fitzinger for Indo-Malayan ratsnakes and the description of a new genus, Oocatochus, for Tropidonotus rufodorsatus Cantor.

Keywords: Serpentes, Colubridae, Coronella, Coelognathus, Elaphe, Gonyosoma, Hierophis, Oocatochus gen. nov., Ptyas, Rhinechis, allozymes, protein electrophoresis, vertebrae, visceral organs, phylogeny.