Acanthosaura phuketensis (Squamata: Agamidae), a new long-horned tree agamid from southwestern Thailand.

We describe a new lowland forest-dwelling species of the genus Acanthosaura from Phuket Island and the Phuket mountain range in southwestern Thailand. Acanthosaura phuketensis sp. nov., the 11^th species in the genus, seems most closely related to A. crucigera from Myanmar and western Thailand and A. cardamomensis from the Cardamom Mountains, but can be differentiated from them by a combination of morphological and coloration characteristics. This new discovery stresses the importance of preserving the last forest patches remaining on Phuket Island, home to three other squamate endemics.