Niviventer rapit (Bonhote 1903)

[Niviventer] rapit (Bonhote 1903), Ann. Mag. Nat. Hist., ser. 7, 11: 123.

Type Locality: Malaysia, Sabah (N Borneo), Gunung Kinabalu.

Vernacular Names: Montane Bornean Niviventer.

Distribution: Highlands of Borneo (specimens in BMNH, MZB, RMBR UMMZ, and USNM); found between 940 and 3360 m on the slopes of Mt Kinabalu in Sabah (Md Nor, 2001), and probably occurs throughout Borneo in mountain forests. In 1998, a large sample was collected by A. J. Gorog on Bukit Baka in Bukit Raya National Park in SW Kalimantan (specimens in UMMZ and MZB).

Conservation: IUCN – Lower Risk (lc).

Discussion: Reviewed and contrasted with other species of Niviventer by Musser (1981 b), who arranged cameroni from the Malay Peninsula and fraternus from Sumatra as subspecies. Musser and Carleton (1993) noted that the "hypothesis that only one species is involved in such a disjunct insular distribution requires evaluation in context of systematic revision of Niviventer ." Recent unpublished multivariate analyses of morphometric variation among samples of all species of Niviventer indicates that the three taxa are morphologically highly distinctive and that each should be treated as a separate species (Musser and Lunde, ms). In those analyses, N. rapit is isolated among species of Niviventer, does not cluster with either N. cameroni or N. fraternus, and differs from the latter two by its long and tufted tail, short molar rows, small bullae, and short and wide incisive foramina, among other traits. Member of the suite of murine species endemic to Borneo (Musser, 1986; see also account of Chiropodomys major).