Indomalayan Leopoldamys

discussion

Discussion: Appreciable morphological variation exists between samples from north and south of Isthmus of Kra, and among insular samples from the Sunda Shelf; systematic revision using a suite of morphological traits and molecular data is required to assess whether variation is characteristic of one or several species (Musser, 1981 b). Recent phylogenetic analyses of mtDNA cytochrome b sequences by Gorog et al. (2004) identified separate lineages, each from Borneo, Sumatra, and the Malay Peninsula forming an unresolved trichotomy, and a Vietnam cluster basal to that trichotomy consisting of a paraphyletic pattern of Vietnamese L. sabanus and L. edwardsi. Gorog et al. (2004) suggested that L. sabanus evolved on the Indochinese mainland and the vicariance patterns revealed by molecular analyses " ... likely have their roots in the Pliocene fragmentation of the Sunda block ... " rather than widespread dispersal across the late Pleistocene Sunda Shelf and subsequent isolation with increasing sea levels. An early preglacial presence of Leopoldamys in the Indochinese region is supported by late Pliocene to middle Pleistocene fossils (Chaimanee, 1998). Usually found in lowland rainforests

Order Rodentia - Family Muridae

distribution

Distribution: SE Bangladesh (Chittagong Hill Tracts, AMNH 251694), Thailand (J. T. Marshall, Jr., 1977 a; Robinson et al., 1995), Vietnam from the north in Tuyên Quang Province to the south in Ninh Thuân Province (Dang et al., 1994; Osgood, 1932; Van Peenen et al., 1969; and four islands off the coast; Kuznetsov, 2000), Laos (Aplin et al., 2003 c; Osgood, 1932; Smith et al., In Press; Van Peenen et al., 1969), S and SW Cambodia (Elephant Mtns, specimens in FMNH; Cardamom Mtns, A. Smith, in litt.), S Burma and most islands in Mergui Arch., Malay Peninsula, Sumatra, Java, Borneo, and smaller islands on the Sunda Shelf except Bali; northern limits unresolved. Range mostly extracted from Musser (1981 c), Corbet and Hill (1992), and study of museum specimens in AMNH, BMNH, FMNH, IEBR, MVZ, MZB, RMBR, RMNH, and USNM.

Order Rodentia - Family Muridae

Leopoldamys sabanus (Thomas 1887)

Leopoldamys sabanus (Thomas, 1887) Long-tailed giant rat—Tikus mondok ekor panjang Hoplopleura malaysiana Ferris, 1921 Polyplax insulsa Ferris, 1923 Polyplax spinulosa (Burmeister, 1838)

An annotated checklist of sucking lice (Phthiraptera: Anoplura) from domestic and wild mammals in Malaysia, with lists of hosts and pathogens

discussion

COMMENTS: Appreciable morphological variation exists between samples from north and south of Isthmus of Kra, and among insular samples from the Sunda Shelf; systematic revision is required to assess whether variation is characteristic of one or more than one species (Musser, 19816). The name macrourus has priority over sabanus, but is based on a specimen of uncertain origin (Musser, 19816).

Order Rodentia - Family Muridae