Leptomys ernstmayri Rummler 1932 Leptomys ernstmayri Rummler 1932, Das Aquarium, 6: 134. Type Locality: Papua New Guinea, Morobe Province, Huon Peninsula, Saruwaged Mtns, Ogeramnang, 1785 m. Vernacular Names: Ernst Mayr's Leptomys. Distribution: Papua New Guinea (above 1500 m in Astrolabe Range west to Kratke Mtns and Purosa region in Eastern Highlands Province, then northeast to mountains on Huon Peninsula; probably occurs farther west in Papuan Central Cordillera, but limits unknown); Prov. of Papua (= Irian Jaya; Arfak Mtns only, Rümmler, 1932, 1938; limits unknown). Reviewed by Flannery (1995 a) and Musser and Lunde (in ms.). Conservation: IUCN – Lower Risk (lc). Discussion: A distinctive species distinguished from L. elegans by the diagnostic morphological traits and altitudinal distributions that were carefully enumerated by Rümmler (1932). It is much smaller in body size and replaces L. elegans at high altitudes in tropical montane rainforest formations; in the Astrolabe Range, for example, L. ernstmayri displaces L. elegans at elevations above 1000 m (Musser and Lunde, in ms.). Usually misidentified as L. elegans in museum collections. The sample from Arfak Mtns may represent a separate undescribed species (K. Helgen, in litt., 2004).

Published as part of Wilson, Don E. & Reeder, DeeAnn, 2005, Order Rodentia - Family Muridae, pp. 1189-1531 in Mammal Species of the World: a Taxonomic and Geographic Reference (3 rd Edition), Volume 2, Baltimore :The Johns Hopkins University Press on page 1351, DOI: 10.5281/zenodo.7316535