313.

Southern Small-toothed Moss Mouse

Pseudohydromys pumehanae

French: Souris-musaraigne de Pumehana / German: Sidliche Moosmaus / Spanish: Raton de musgo de dientes pequenos meridional

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

“NNW slopes of Mt Bosavi (= Mt Leonard Murray; 6°33’S, 142°50’E, Southern Highlands Province, Papua New Guinea ...), 2100 m, in the Kikori River basin.”

Pseudohydromys pumehanae was referred by K. M. Helgen and L. E.Helgen to an el lermani species group that also includes P. carlae, P. ellermani, and P. germani . A population on Mount Karimui, in Chimbu

Province, mapped and figured by T. F. Flannery as Mayermys [= Pseudohydromys] ellermani, is accepted here as belonging to P. pumehanae . No other species of Pseudohydromys are recorded from any of the isolated volcanic peaks that run along southern flanks of the Central Range of Papua New Guinea, among which Mounts Bosavi and Karimui are prominent examples. Monotypic.

Distribution. Known only from type locality in the upper Strickland River catchment and from N flanks of Mt Karimui, E New Guinea.

Descriptive notes. Head-body 96-101 mm, tail 100-103 mm, ear 11-12 mm, hindfoot 21-23 mm; weight 17-20 g. 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; narrow hindfeet, 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 fewer per quadrant. Members of the ellermani species group have one small molar per quadrant, forward-projecting upper incisors, smoky-gray fur above and below, with no grizzling or white spotting on rump, and vibrissae extending just past ears; they also share a suite of distinctive cranial traits. The Southern Smalltoothed Moss Mouse is a medium-sized member of the group, with fur on upperparts very short (4 mm) and velvety, smoky gray, but darker gray on crown and anterior part of back; fur on underparts slightly paler; ears small and pale gray; upper surfaces of feet pale gray, with short white hairs; tail (averages 102% of head-body length) is dark gray and mottled, but lacking white tip, has slightly hairy appearance with hairs equal to 1-5-2 scale lengths. Spermatozoa (reported as Mayermys ellermani from Mount Karimui) with head 9 pm long and 3 pm wide, with apical hook and two accessory ventral hooks, tail 114 pm.

Habitat. No specific habitat information is available for type locality, but regional habitat at 2100 m on Mount Bosavi is evergreen, lower montane rainforest. Capture site on Mount Karimui was lightly disturbed primary lower montane rainforest with dense

stands of climbing bamboo ( Nastus productus, Poaceae) and a sparse understory of ferns and herbs, at elevations of 1550 m.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. All captures have been made on the ground. At the Mount Karimui capture site, an individual of Southern Small-toothed Moss Mouse was seen climbing along vines suspended in a low sapling; this is the only recorded evidence ofscansorial behavior by any species of the genus.

Movements, Home range and Social organization. No information.

Status and Conservation. Not assessed on The IUCN Red List. The elevational range of the Southern Small-toothed Moss Mouse in southern-central Papua New Guinea coincides with a zone of extensive habitat modification following long-term subsistence agricultural activities. Lower montane rainforests on Bosavi and Karimui mountains, although still largely intact, are potentially vulnerable to forestry activities.

Bibliography. Flannery (1995b), Helgen (2005), Helgen & Helgen (2009), Jackson & Woolley (1993), Musser & Carleton (2005).