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 62. Long-haired Spiny Tree-rat Mesomys leniceps French: Rat-épineux du Pérou / German: LanghaarAmazonas-Stachelratte / Spanish: Rata arboricola de pelo largo Other common names: Peru Spiny Tree-rat , Woolly-headed Spiny Tree-rat Taxonomy. Mesomys leniceps Thomas, 1926 , “Yambrashbamba, Amazonas, 1830 m,” Peru . Mesomys leniceps may only represent a regional variant of the widespread M. hispidus. Monotypic. Distribution. E Andean slopes of N Peru (Amazonas and San Martin regions). Descriptive notes. Head-body 180 mm, tail 214 mm. No specific data are available for body weight. Long-haired Spiny Tree-rat has brownish and rusty-red dorsal fur that is not as spiny as other species of Mesomys . Spines average 20 mm in length, are freely mixed with softer hairs within the fur, and lack distinct pale tips of other species of Mesomys . Head of the Long-haired Spiny Tree-rat is hairier than back, slightly “hispid” to the touch. Venter is hairier, rich ocherous overall but with large white patches in axillary and inguinal areas. Forefeet and hindfeet are pale buff above with white digits. Tail is 118% of head-body length and brown along its length; body hair extends farther onto base oftail than in other species (25 mm on average). Tail scales are also smaller, and scalar hairs are more appressed to the shaft. Long tuft of hairs extends distally from tail tip. Skull of the Long-haired Spiny Tree-rat is similar to those of the Tuft-tailed Spiny Tree-rat and other species of Mesomys but differs from the latter in several features, including more slender rostrum, nasals that do not extend behind premaxillary process, incisive foramina that are posteriorly narrowed,jugal and frontal bones around anterior orbital foramina slender such that height of zygoma itself is distinctly narrower, anteroposteriorly divergent molar tooth rows, and cheekteeth that decrease notably in size from dP* to M” . Habitat. Known only from upper montane rainforest on the eastern slope of the northern Andes in Peru at elevations of 1554-1980 m. Food and Feeding. There is no specific information available for this species, but the Long-haired Spiny Tree-rat likely has omnivorous to herbivorous habits of its congeners. Breeding. There is no information available for this species. Activity patterns. There is no information available for this species. 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. Habitats in vicinity ofthe type locality of the Long-haired Spiny Tree-rat are under strong pressure from human expansion and related logging activities. Additional studies on distribution, habitat, abundance, ecology, and conservation threats to Long Haired Spiny Tree-rat are needed. Bibliography. Cabrera (1961), Eisenberg & Redford (1999), Ellerman (1940), Emmons (1990, 1997a, 2005), Patton et al. (2015), Tate (1935), Thomas (1926b), Thomas & St. Leger (1926), Upham et al. (2013), Woods (1993), Woods & Kilpatrick (2005).