Echimyidae Author Don E. Wilson Author Thomas E. Lacher, Jr Author Russell A. Mittermeier text 2016 2016-07-31 Lynx Edicions Barcelona Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I 552 604 book chapter 67690 10.5281/zenodo.6623649 5be7e52f-9b9c-4c03-99ed-f346bbcde1d0 978-84-941892-3-4 6623649 78. Bare-tailed Tree-rat Pattonomys occasius French: Rat-épineux a queue nue / German: Nacktschwanz-Tupfelbaumratte / Spanish: Rata arboricola de cola desnuda Other common names: Bare-tailed Armored Tree-rat Taxonomy. Echimys occasius Thomas, 1921, “Gualea, west of Pichincha. Alt. 4000’ [= 1219 m],” Pichincha, Ecuador. According to L. H. Emmons in 2005, the type locality on the western slope of the Andesis very likely an error. This species is monotypic. Distribution. W Amazon Basin of E Ecuador and E Peru. Descriptive notes. Head-body 218 mm, tail 225 mm. No specific data are available for body weight. The Bare-tailed Tree-rat is the smallest and most distinct species of Pattonomys . It has dark buff-brown upper parts, streaked with dark brown. Venter is clear creamy orange, often with white thoracic and abdominal regions. Dorsal pelage is heavily spined, especially over rump. Dark-brown spines are long sharp, flexible, and wide but differ from other species of Pattonomys by having a pale rusty rather than white tips on rump, while remaining completely gray brown on flanks. Spine tips are blunt and lack hair-like process extending from tips. Fine, soft, and sparse orange hairs occur between spines over body. Head is covered with stiff but thin bristles. Ears are short and naked, and muzzle and cheeks are reddish. Vibrissae are fine, thin, and long, with mystacial vibrissae reaching posterior to shoulders. Body hair extends onto base of tail for 10-20 mm; rest oftail is conspicuously naked and scaly. Robusttail is 103-110% of head-body length and dark brown. Thighs and tail base are dull brown. Hindfeet are short and broad and have stout claws; dorsal surface is brown. Females have two pairs of lateral mammae. Skull is smaller than other species of Pattonomys , auditory bullae are not inflated, and supraorbital ridges are very weakly developed. Habitat. l.owland Amazonian rainforest at elevations of 120-575 m (based on fewer than ten specimens in museum collections). Food and Feeding. There is no specific information available for this species, but the Bare-tailed Tree-rat is likely herbivorous, feeding on fruits, seeds, and other plant materials. Breeding. There is no information available for this species. Activity patterns. There is no specific information available for this species, but the Bare-tailed Tree-rat has been reported to be nocturnal. Movements, Home range and Social organization. There is no information available for this species. Status and Conservation. Classified as Data Deficient on The IUCN Red List. Additional studies on distribution, habitat, ecology, abundance, and conservation threats to the Bare-tailed Speckled Tree-rat are needed. Bibliography. Eisenberg & Redford (1999), Ellerman (1940), Emmons (1990, 1997a, 2005), Patton et al. (2015), Tate (1935), Thomas (1921c¢, 1928b), Woods (1993), Woods & Kilpatrick (2005).