Reptiles of Phetchaburi Province, Western Thailand: a list of species, with natural history notes, and a discussion on the biogeography at the Isthmus of Kra

A study of herpetological biodiversity was conducted in Phetchaburi Province, in the upper part of peninsular Thailand. On the basis of a review of available literature, original field observations and examination of museum collections, a preliminary list of 81 species (12 chelonians, 2 crocodiles, 23 lizards, and 44 snakes) is established, of which 52 (64 %) are reported from the province for the first time. The possible presence of additional species is discussed. Some biological data on the new specimens are provided including some range extensions and new size records. The herpetofauna of Phetchaburi shows strong Sundaic affinities, with about 88 % of the recorded species being also found south of the Isthmus of Kra. A biogeographic affinity analysis suggests that the Isthmus of Kra plays the role of a biogeographic filter, due both to the repeated changes in climate during the Quaternary and to the current increase of the dry season duration along the peninsula from south to north. A biogeographic boundary seems to occur at the northern end of the peninsula, corresponding with the current position of a dry season of four month’s duration.