Forbes's Chiruromys

discussion

Discussion: Significance of the appreciable geographic variation in body size and other traits recently assessed by Musser and Lunde (ms) who provided results of multivariate analysis of morphometric variation in samples from the mainland of E Papua and the three largest D’Entrecasteaux Isls (Goodenough, Fergusson and Normanby). Within the island samples, that from Goodenough averages larger in cranial dimensions than the other two, and as a group the three insular samples average larger than those from mainland Papua in both cranial and dental dimensions. The names satisfactus and major were applied to samples from Goodenough Isl (Tate and Archbold, 1935), and shawmayeri to specimens from Fergusson Isl (Laurie, 1952). The contrast between mainland and insular populations reflects some evolutionary divergence in the island populations after separation from the mainland at the end of the Pleistocene when sea levels rose. The D’Entrecasteaux Isls are on the continental shelf and have likely been either connected to or separated from mainland Papua at several times during glacial and interglacial Pleistocene intervals, which provided intermittent periods of gene flow between island an

Order Rodentia - Family Muridae

distribution

Distribution: Papua New Guinea; endemic to mainland of SE Papua New Guinea, sea level to 700 m. Not recorded west of Oomsis Creek in valley of Markham River (see map of this region in Brass, 1959), and extends eastward to Bara Bara near Milne Bay (Thomas, 1897 a); also on D'Entrecasteaux Isls (Goodenough, Fergusson, and Normanby). Occurs in lowlands (sea level to 700 m) on the mainland, but up to 1300 m on Goodenough Isl and nearly 900 m on Normanby Isl (Flannery, 1995 a, and specimens in AMNH). Dennis and Menzies (1979) included the Louisiade Isls in the range, but samples in AMNH of Chiruromys from there are not forbesi but examples of a separate undescribed species (Musser and Lunde, ms).

Order Rodentia - Family Muridae

materials_examined

Type Locality: Papua New Guinea, Central Province, Astrolabe Range, Sogeri, 1500 ft (458 m).

Order Rodentia - Family Muridae

discussion

COMMENTS: Significance of the appreciable geographic variation in body size and other traits needs to be assessed in a critical systematic review of the species.

Order Rodentia - Family Muridae