Chilomys instans (Thomas 1895) [Oryzomys] instans Thomas 1895, Ann. Mag. Nat. Hist., ser. 6, 16: 368. Type Locality: Colombia, Cundinamarca Dept., Bogotá region, Hacienda de La Selva, 4600 ft (1402 m). Vernacular Names: Andean Chilomys. Synonyms: Chilomys fumeus Osgood 1912. Distribution: N Andes, from C Ecuador (Musser et al., 1998:106), through C and N Colombia, to W Venezuela (Handley, 1976; Linares, 1998). Conservation: IUCN – Lower Risk (lc). Discussion: Osgood (1912) described fumeus (type locality: Colombia, Norte de Santander, Páramo de Tamá) as a species distinct from C. instans; however, Cabrera (1961) relegated it to subspecific status, as also observed by Linares (1998), and the genus has thereafter been viewed as monotypic (e.g., Corbet and Hill, 1991; Honacki et al., 1982; Musser and Carleton, 1993). Osgood’s employment of subspecies was especially robust so that he chose to diagnose fumeus as a species is by itself instructive. In view of the other valid species described from the Páramo de Tamá region (e.g., Oligoryzomys griseolus, Thomasomys hylophilus), the status of fumeus invites another appraisal.

Published as part of Wilson, Don E. & Reeder, DeeAnn, 2005, Order Rodentia - Family Cricetidae, pp. 955-1189 in Mammal Species of the World: a Taxonomic and Geographic Reference (3 rd Edition), Volume 2, Baltimore :The Johns Hopkins University Press on page 1110, DOI: 10.5281/zenodo.7316535