Zoogeography of Vietnamese primates

Abstract

Based on geographic complementarity of congeneric taxa, the 22 species or well-defined subspecies of primates that inhabit Vietnam may be allocated to nine zoogeographic groups (lorises, two; macaques, three; langurs, three; gibbons, one). Analysis of group distributions reveals two major patterns: (1) four of the six non-macaque groups are essentially restricted to the eastern part of the Indochinese Peninsula, east of the Mekong River; and (2) species and subspecies in seven of the nine groups reach their northern or southern limits of distribution in central Vietnam, at 14–17‡N. The first pattern suggests that the Mekong River has been an important barrier to westward dispersal of nonmacaque primates in continental Southeast Asia. The second pattern suggests that a Zoogeographic barrier formerly extended east and west across Vietnam at ca. 14–17‡N.