Hesperomys caliginosus Tomes, 1860 Cricetidae Don E. Wilson Russell A. Mittermeier Thomas E. Lacher, Jr 3Z9DC Tomes 1860 [1911,2343,1067,1113] Mammalia Cricetidae Melanomys Animalia Rodentia 178 457 Chordata species caliginosus    505.    Dusky Rice Rat    French: Mélanomys sombre/ German: Dunkelreisratte/ Spanish: Rata arrocera oscura   Other common names: Dusky Melanomys   Taxonomy. Hesperomys caliginosus Tomes, 1860,  Esmeraldas, Esmeraldas, Ecuador.   M. caliginosusincludes Oryzomys phaeopus Thomas, 1894, type species of the genus Melanomys Thomas, 1902. Several nominal forms are currently subsumed under M. caliginosus, including Oryzomys phaeopus, O. phaeopusobscurior, O. phaeopusolivinus, O. ( Melanomys) obscurior affinis, Melanomys caliginosusoroensis, M. affinis monticola, M, phaeopusvallicola, M. phaeopustolimensus, M. lomitensis, and M. buenavistae. As for the entire genus, taxonomy in M. caliginosusneeds a comprehensive revision. Monotypic.    Distribution.WC Colombia S to SW Ecuador.   Descriptive notes.Head—body 100-140 mm, tail 70-111 mm, ear 16 mm, hindfoot 24-28 mm. The Dusky Rice Rat is geographically variable but overall very dark dorsally. See general characters of the genus under the Black-and-Yellow Rice Rat ( M. chrysomelas) account. Upperparts are brown washed, rather pale yellow and finely lined with black, especially along middle of back; underfur is grayish plumbeous, with hairs black basally; sides are less dark and more yellowish than middle of back; venteris pale gray at base, tipped with pale buffy yellow, forming heavy conspicuous yellow wash; tail, ears, and feet are dark brown; and tail is naked, faintly lighter below than above.   Habitat.Andean and Pacific forests from sea level to elevations of ¢.2300 m.   Food and Feeding.No information.   Breeding.In Choc6, Colombia, reproductively active Dusky Rice Rats were recorded in March; a pregnant female gave birth to two young.   Activity patterns.The Dusky Rice Ratis terrestrial.   Movements, Home range and Social organization.No information.   Status and Conservation.Classified as Least Concern on The IUCN Red List.   Bibliography.Allen (1913b), Cadena et al. (1998), Cassola (2016ab), Hanson & Bradley (2008), Thomas (1902d), Weksler & Loss (2015). 3818814827 [2145,2620,1284,1309] 178 457