Sundamys muelleri (Jentink, 1879) . Notes Leyden Mus., 2:16.

TYPE LOCALITY: Indonesia, W Sumatra, Batang Singgalang, Padang Highlands .

DISTRIBUTION: Sunda Shelf only: SW peninsular Burma, peninsular Thailand, Malay Peninsula, Sumatra, Borneo, Palawan, and many smaller islands on the Shelf; records from islands off of Sunda Shelf (Nicobars, for example) proved to represent other species (see maps in Musser and Newcomb, 1983).

SYNONYMS: balabagensis, balmasus, borneanus, campus, chombolis, crassus, credulus, culionensis, domitor, firmus, foederis, integer, otiosus, pinatus, pollens, potens, sebucus, terempa, valens, validus, victor, virtus, waringensis.

COMMENTS: Morphological, chromosomal, and spermatozoal data suggested S. muelleri is a distant relative of Rattus but in the same monophyletic clade (Breed and Yong, 1986; Musser and Newcomb, 1983). Populations from SW Burma, Peninsular Thailand, and the Malay Peninsula are significantly larger in body size than those from elsewhere on the Sunda Shelf and may be different species (Musser and Newcomb, 1983).