Description of a new species of Sylvisorex (Insectivora: Soricidae) from Tanzania Paulina D. Jenkins Department of Zoology, British Museum (Natural History), Cromwell Road, London SW7 5BD Introduction Two species of Sylvisorex are known from Tanzania, S. granti Thomas, 1907 which has been reported from Mount Kilimanjaro and S. megalura (Jentink, 1888) of which specimens from three separate localities have been recorded recently by Howell & Jenkins (in press). In the course of organised collecting in Tanzania, Dr K. M. Howell of the University of Dar-es-Salaam obtained a number of shrews which were submitted to the British Museum (Natural History) for identification. These include a single example of Sylvisorex which on examin-ation proves to differ substantially from all the known species of the genus in size and dental morphology, which is described here as new. The specimen differs externally from other members of the genus in the presence of bristle-hairs on the tail. The absence of such bristle-hairs has been used to distinguish Sylvisorex from Suncus but this distinction must now depend on the cranial differences elaborated by Heim de Balsac & Lamotte (1957) plus the dental characters used by Repenning (1967) and Butler & Greenwood (1979). The most readily applied of these latter characters is the presence of denticulations on the cutting surface of the first lower incisor in Sylvisorex, which are lacking in Suncus; also in Sylvisorex the talon of the upper premolar is more highly developed, the interorbital region broader and the braincase broader and higher relative to skull size. Additionally the hindfeet in Sylvisorex are larger relative to body size with slightly elongated, staggered, separated, metatarsal pads, while Suncus has smaller hindfeet with more oval, more or less adpressed pads. All measurements are in millimetres: the dental nomenclature follows that of Swindler (1976), Butler & Greenwood (1979) and is illustrated in Figure 1. Systematic Section Sylvisorex howelli sp. nov. HOLOTYPE. BM(NH) 82.874 adult of undetermined sex (viscera and external genitalia removed) in alcohol, skull removed; collected 27 April 1982 on Bondwa Peak, Uluguru North Forest Reserve, Uluguru Mountains, Morogoro District, Tanzania, c. 0654'S 3740'E, c. 1050m on road through forest by M. K. S. Maige and donated by Dr K. M. Howell. DIAGNOSIS. Small, size intermediate between S. johnstoni (Dobson, 1888) and S. granti; tail with bristle-hairs; braincase shallow and long, relative to skull length; lingual edge of second upper unicuspid projecting beyond that of first, level with lingual edge of third unicuspid; crown area of fourth upper unicuspid smaller than crown area of second upper unicuspid; parastyle of upper premolar low and slender; posterolingual ridge on first lower incisor very prominent, forming a small cusp; talonid of third lower molar reduced. (See Figs 2-8). Bull. Br. Mm. nat. Hist. (Zool.) 47(1): 65-76 Issued 28 June 1984 65
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