164.

Mount Anacuao Tree Mouse

Musseromys anacuao

French: Rat de I/Anacuao / German: Mount-Anacuao-Bergwaldmaus / Spanish: Ratén arboricola de Anacuao

Other common names: Sierra Madre Tree Mouse

Taxonomy. Musseromys anacuao Heaney et al., 2014,

0-2 km E Mt. Anacuao Peak, Lu-zon Island, Philippines.

Recently described, using a multidisciplinary approach combining morphoanatomy, morphometrics, and molecular phylogeny. A first cytochrome-b phylogeny reveals its affinities with other Musseromys species. The species was further validated and shown to be closely related to M. beneficus on morphological and molecular grounds by D. S. Balete and colleagues in 2015. Monotypic.

Distribution. Known only from Mt Anacuao, Luzon I, Philippines.

Descriptive notes. Head—body 78-83 mm, tail 82-86 mm, ear 15-16 mm, hindfoot 18 mm; weight 17-21 g. A small mouse characterized,like all its congeners, by a broad head, a short, blunt rostrum, and twosets oflong vibrissae on the head. The second set of vibrissae starts from a small patch of bare skin just behind the eyes. Pelage is soft and rusty brown dorsally and buffy reddish ventrally. Tail is about the same length as, or slightly longer than (99-116%), the head-body and it ends with rather long dark hairs. Feet are pale; hindfeet are broad with proportionately large plantar pads. Ears are fairly long and rounded, being more rounded than in the Mount Banahaw Tree Mouse ( M. gulantang) but narrower and slightly more pointed than in the Mount Pulag Tree Mouse ( M. beneficus). Skull is smaller than other species of Musseromys, with broad lingual breadth ofpalate at M3 but narrow labial palatal breadth at M1, narrow zygomatic plates, short molar rows and narrow M1, and short nasals and rostrum, as well as a long incisive foramin, a very shallow squamosal notch and pale orange anterior surface ofincisors. Females bear two pairs ofinguinal mammae.

Habitat. Mossy forest with elaeocarps, oaks, laurels, myrtles, coniferous podocarps, and a lot of epiphytes,at elevations of around 1700 m.

Food and Feeding. Little is known, but the snap traps used to capture the specimens were baited with slices of fried coconuts covered in peanut butter.

Breeding. Two females, one subadult and another with one embryo, and one male with scrotal testes where capture in May.

Activity patterns. The Mount Anacuao Tree Mouse is arboreal and has been captured at night at c.1-3 m aboveground.

Movements, Home range and Social organization. No information.

Status and Conservation. Not assessed on The IUCN Red List. Known from only three specimens from the type locality, although the species probably has a wider distribution on other mountains in Luzon.

Bibliography. Balete et al. (2015), Heaney, Balete & Rickart (2016), Heaney, Balete, Rickart, Veluz & Jansa (2014).