The biogeography of the Isthmus of Kra region: a review


J. Parnell, Herbarium, School of Botany, Trinity Centre for Biodiversity Research, Trinity College Dublin, Dublin 2, Ireland. E-mail:


This review examines the evidence for a significant biogeographic divide on the Thai–Malay Peninsula of mainland southeast Asia (SE Asia) associated with the Isthmus of Kra. The divide is believed to be of the same scale as ‘Wallace’s Line’, though it remains less well-known, less well-studied, and its location and cause are enigmatic. This review presents relevant geological, geographical, climatic, biogeographic and sea-level data, discusses some exemplar distributional patterns and concludes with an integrated discussion.