188. Bornean Pygmy Shrew Suncus hosei French: Pachyure de Hose / German: Borneo-Wimperspitzmaus / Spanish: Musarana pigmea de Borneo Other common names: Hose's Pygmy Shrew, Hose's Shrew Taxonomy. Crocidura (Pachyura) hosel Thomas, 1893, “ Bakong River, Baram, East Sarawak,” Malaysia. Suncus hosei was originally described under the generic name Crocidura (Pachyura), and F. N. Chasen in 1940 reclassified it in Suncus. J. R. Ellerman and T. C. S. Morrison-Scott in 1951 considered it a geographical form of S. etruscus. R. Hutterer in 2005 split it to a distinct species based on its morphology. Future molecular stud- ies are needed to testpe ofits status as a distinct species. Monotypic. Distribution. Restricted to Borneo; probably widespread, although just known from a few scattered localities in N Borneo: Sabah (Kinabalu Park, Crocker Range, and Sepilok), Sarawak (Bakong River, Mulu, and Lanjak Entimau Wildlife Sanctuary), and Brunei (Belalong). Future field studies in Kalimantan (Indonesia) will likely expand its range. Descriptive notes. Head-body 53-59 mm, tail 20-28 mm, hindfoot 8-6—10 mm; weight 2-5 g. The Bornean Pygmy Shrew is very small, and its furis short, crisp, and velvety. Dorsum is deep smoky gray, finely grizzled with whitish; venter is rather paler; and ears, feet, and tail are dark brown. Tail is very short, slender, and closely haired, with a few longish hairs usually scattered among shorter ones. Anterior part of first incisor is short and thick; posterior cusp is about equal in size to one of the two posterior unicuspids. First unicuspid is large,its tip reaching same level as first incisor and tip of large premolar; second and third unicuspids are about equal in size, with second slightly longer but slenderer than third; and fourth is well developed, with its tip just visible externally and about equal in height to basal process of large premolar and about one-half the height of third. Anterior lower incisoris long and slender, without denticulations; second lower unicuspid is just higher than anterior cusp of large premolar. Its largersize, shorter tail, less flattened skull, and presence of an accessory cusp on anterior side of first unicuspid seem also to distinguish it from other pygmy shrews. Regarding other sympatric shrews, the Bornean Pygmy Shrew can be externally identified byits small size (less than 60 mm), which sets it apart from all species except the Neglected White-toothed Shrew (Crocidura cf. neglecta), which it can be distinguished from byits shorter tail that is always less than 50% of head-body length, while tail of the Sunda White-toothed Shrew is ¢.70% of head-body length. Habitat. Primary lowland dipterocarp forest and secondary forest. The Bornean Pygmy Shrew is distributed at elevations from sea level up to 800 m. It is probably rare higher than 550 m because it has not been captured during intensive shrew surveys in Sabah at that elevations and at 900 m. Food and Feeding. The Bornean Pygmy Shrew is insectivorous, although it might eat carcasses when available because it is attracted by salted fish bait. Breeding. No information. Activity patterns. No information. Movements, Home range and Social organization. Little is known about spatial ecology of the Bornean Pygmy Shrew, but given the low number of records,it is clearly less abundant or more patchily distributed than the syntopic Bornean White-toothed Shrew (Crocidura foetida). Status and Conservation. Classified as Data Deficient on The IUCN Red List. There is an absence of recent information on extent of occurrence, status, and ecological requirements of the Bornean Pygmy Shrew. Bibliography. Camacho-Sanchez & Hinckley (2016), Charles (1996), Chasen (1940), Corbet & Hill (1992), Ellerman & Morrison-Scott (1951), Gerrie & Kennerley (2016b), Hawkins et al. (2018), Hinckley et al. (2016), Hutterer (2005b), Medway (1965), Phillipps & Phillipps (2016), Thomas (1893), Tingga et al. (2011), Yasuma et al. (2003).

Published as part of Russell A. Mittermeier & Don E. Wilson, 2018, Soricidae, pp. 332-551 in Handbook of the Mammals of the World – Volume 8 Insectivores, Sloths and Colugos, Barcelona :Lynx Edicions on page 461, DOI: 10.5281/zenodo.6870843