303.

Bishop Moss Mouse

Pseudohydromys berniceae

French: Souris-musaraigne de Bishop / German: Bishop-Moosmaus / Spanish: Raton de musgo de Bishop

Taxonomy. Pseudohydromys berniceae K. M. Helgen & L. E.Helgen, 2009,

“immediate vicinity of Bunisi Village (10°01.3’S, 149°35.7E, Milne Bay Province, Papua New Guinea ...), 1490 m, north slopes of Mt Simpson, Maneau Range.”

All known specimens of P. berniceae were collected in 2003-2004 and remained unremarked prior to the species description in 2009. Referred by K. M. Helgen and L. E. Helgen to a murinus species group that

also includes P. murinus and P. eleanorae . It may be noted that two other members of this genus ( P. murinus and P. germani) were collected syntopically (in the same pitfall line). Monotypic.

Distribution. Known only from three localities in two mountain ranges on the Papuan Peninsula of New Guinea: Mt Obree, in the Owen Stanley Range, and Mt Simpson and Mt Pekopekowana, in the Maneau Range.

Descriptive notes. Head-body 70-80 mm, tail 79-88 mm, ear 9-11 mm, hindfoot 18-20 mm. No specific data are available for body weight. Genus Pseudohydromys is a taxonomically diverse group of small-bodied murines characterized by dense, velvety to plush fur; a variably narrowed and flattened head with small eyes and ears; head generally without contrasting pattern; vibrissae fine and elongate, extending past ears; eyes small to minute; hindfeet narrow, lacking webbing between digits, and with claws on all digits; tail narrow and thinly furred, approximating to combined length of head and body; mammae (when known) two on each side, both inguinal; cranium delicately built, with small molars reduced in number to two or few perquadrant. Members of the murinus species group have two molars per quadrant, relatively unreduced in size compared with members of otherspecies groups; they also share a suite of special cranial traits. The Bishop Moss Mouse is smallest member of genus; fur is very short (less than 5 mm) and dark brownish gray on upperparts and below, with no contrasting markings on head; vibrissae fine and elongate, extending well past ears; eyes very small; ears small and dark gray; upper surfaces of forefeet white; upper surfaces of hindfeet pigmented and with dark gray hairs except on digits, which are white; tail averages 11% longer than head-body length, dark for most of its length but sometimes mottled or with white tip.

Habitat. All records are from evergreen tropical forest, ranging from hill forest on Mount Pekopekowana to lower montane rainforest on Simpson and Obree mountains; recorded at elevations of 590-1570 m.

Food and Feeding. No information.

Breeding. The low mammary formula (two pairs) indicates small litter size. Holotype was a pregnant female with two embryos.

Activity patterns. Body proportions suggest terrestrial lifestyle, and entirely dark color suggests nocturnal activity.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Least Concern on The IUCN Red List in recognition oflikely geographic range greater than 42,000 km* and lack of any identified major threats. Forestry activities and conversion of evergreen forest to plantations are occurring at a relatively high rate in many parts of the Papuan Peninsula.

Bibliography. Engelbrektsson (2016d), Helgen & Helgen (2009), Jackson & Woolley (1993), Musser & Carleton (2005).