Phylogenetic relationships among venomous snakes of the genus Agkistrodon from Asia and the North American continent.

Abstract

AMONG a great number of venomous snakes, Agkistrodon is the only genus which is found in both Asia and the North American continent. The Asiatic members of Agkistrodon consist of seven species and range from Japan, Formosa, China, south-east Asia (excluding Celebes and Philippines), India, Central Asia and southern Siberia, to the borders of the Caspian Sea and the Ural River. Three species of Agkistrodon are distributed on the North and central American continents, and are found in the south-eastern portion of the United States, all of Mexico and most of Central America. The Agkistrodon of Asia and America are morphologically similar.