GEOGRAPHICAL VARIATION IN THE MORPHOLOGY OF 4 SNAKE SPECIES FROM THE LESSER SUNDA ISLANDS, EASTERN INDONESIA

The morphology of three colubrid snakes, Elaphe subradiata, Psammodyna stes pulverulentus, Lycodon aulicus capucinus, and the viper Trieresur us albolabris, were examined from populations throughout the Lesser Su nda islands using canonical Variate analysis. The Lesser Sundas form t he western part of two extensive island chains, the Banda Area, that l ie between the large islands on the Sunda (Asian) and Sahul (Australia n) continental shelves. The snakes of the Lesser Sunda islands show co nsiderable intraspecific variation in morphology. Populations of Trime resurus albolabris from Wetar and Psammodynastes pulverulentus from Al or show the greatest morphological separation from conspecifics. The m ost pronounced morphological differentiation in multidimensional space occurs between populations on islands that remained separated through out the Pleistocene, when sea levels were about 120m lower than presen t. Consensus tree evaluation of Mahalanobis distance for populations o f these four species and Dendrelaphis pictus on the islands of Lombok, Sumba, Flores, Lembata and Alor, supports the finding that population s from islands that remained isolated throughout the Pleistocene by se a barriers show the greatest morphological divergence. (C) 1996 The Li nnean Society of London