Species Diversity, Distribution and Proposed Status of Monitor Lizards (Family Varanidae) in Southern Thailand

Abstract

Field studies of species diversity and distribution of monitor lizards were carried out from January 1998 to February 2000. Four species were found in southern Thailand, comprising Varanus salvator (Laurenti, 1768), V. rudicollis (Gray, 1845), V. bengalensis nebulosus (Gray, 1831) and V. dumerilii (Schlegel, 1839). V. flavescens (Hardwicke and Gray, 1827) and the Varanus salvator komaini Nutphand, 1987 were not found during the field survey. V. salvator and V. b. nebulosus distributed throughout southern Thailand in undisturbed forests and agricultural areas while V. rudicollis and V. dumerilii were usually found in undisturbed forests. The former three species distributed in three main mountain ranges (MR); Phuket MR, Nakhon Si Thammarat MR and San Kara Kiri MR, whereas the latter was found only in Nakhon Si Thammarat MR and San Kara Kiri MR. All species are being threatened by human activities. In Southern Thailand based on the IUCN's criteria for the categories of threat, V. salvator and V. b. nebulosus should be classified under the vulnerable category while V. rudicollis and V. dumerilii should have endangered status. Varanus salvator komaini is critically endangered and its natural habitat is still unconfirmed.