Crocidura newmarki, Stanley & Hutterer & Giarla & Esselstyn, 2015

Stanley, William T., Hutterer, Rainer, Giarla, Thomas C. & Esselstyn, Jacob A., 2015, Phylogeny, phylogeography and geographical variation in the Crocidura monax (Soricidae) species complex from the montane islands of Tanzania, with descriptions of three new species, Zoological Journal of the Linnean Society (Zool. J. Linn. Soc.) 174 (1), pp. 185-215 : 204-205

CROCIDURA NEWMARKI SP. NOV.

( FIGS 7 , 9 , 12 ; TABLES 3, 4, 6)

Holotype: FMNH 208439, an adult male, with slightly worn molars (age class II; see Methods and Materials), prepared as a round skin, skull, skeleton and frozen tissue (liver); collected by M. J. Munissi (original field number W.T.S. 9955) on 9 August 2009. The condition of the skin, skull and skeleton are good.

Paratypes: We designate as paratypes five females and four males: FMNH 208440, collected at the type locality (see below) at 3600 m elevation; FMNH 208444 and 208447, collected at Mt Meru, Arusha National Park, Meru Crater, 3.24200°S, 36.78736°E, 2652 m ; FMNH 208435 and 208436, collected at Mt Meru, Arusha National Park , Mgongo wa Tembo, 3.22350°S, 36.78675°E, 3000 m ; FMNH 208415 and 208416, collected at Mt Meru, Arusha National Park, 3.24725°S, 36.80066°E, 2300 m ; FMNH 208406 and 208411, collected at Mt Meru, Arusha National Park , Fig Tree Arch, 3.24406°S, 36.82845°E, 1950 m . All type materials are preserved as skins, skulls and either fluidpreserved post-cranial bodies, or cleaned post-cranial skeletons.

Type locality: Tanzania, Arusha Region, Arumeru District, Mt Meru , Arusha National Park, near Saddle Hut , 3.21609°S, 36.76897°E, 3600 m .

Measurements of holotype: Measurements were all recorded by W.T.S. and are in millimetres and weight in grams: TL: 131; HB: 81; TV: 50; tail pilosity: 67%; HF:

16; EAR: 9; WT: 8.5 g; CI: 20.59; BL: 18.44; PPL: 9.20; PGW: 6.53; UTRL: 8.98; LIW: 4.95; BW: 6.34; NW: 1.79; GW: 9.67; HBC: 6.63; I 3 -W: 0.68; CW: 0.68; M 3 -L: 1.53; M 3 -W: 0.79; MP: 0.92; MI: 13.06; LTR: 8.34.

Diagnosis: Crocidura newmarki is a medium-sized, dark shrew similar to Crocidura montis Thomas, 1906 from Rwenzori Mountains, but with a less hairy tail (pilosity 67% versus 81% in C. montis ; Table 6); head and body length 65–85 mm, tail 45–60 mm and mass 6–11 g ( Table 3). It is smaller than any of the other shrews allied to C. monax in Tanzania, except C. mdumai . The proximal two-thirds of the tail bears numerous long, translucent bristles (up to 7 mm in length); the rest of the tail is covered in short, dark brown applied hairs. The pelage is dark brown on the dorsum and is only slightly more greyish brown on the venter; hairs of the back are 6–7 mm in length at mid-dorsum. The dorsal surfaces of both the front and the back feet are slightly paler than the rest of the body. The longest vibrissae emanating from the snout are 15 mm in length.

The skull of C. newmarki is small and wedgeshaped with a rounded braincase, smaller than any of the other OTUs considered in this study, except for C. mdumai , which is even smaller ( Fig. 12 ; Table 4). The lateral profile of the skull is straight and slightly rounded towards the braincase. The first upper incisor is short and slender ( Figs 9 , 12 ), barely reaching as low as the tip in I 2. The upper unicuspids are narrow, with small cingula ( Fig. 9 ).

Description and comparisons: Crocidura newmarki is a medium-sized shrew with long woolly fur. The head and body length range is 65–85 mm, tail length is 45– 60 mm, the length of the hindfoot is 13–16 mm, and mass is 6–11 g. In total, 58–95% (mean 67.2%) of the tail is covered by long bristle hairs. However, bristles are scattered and less numerous than in C. montis ( Table 6). Vibrissae extend up to 15 mm in length. The ear conch is stout. The hairs of the dorsal and ventral pelage, which are 6–7 mm long, are grey but the tips are a rich brown. The dorsal aspects of the feet are paler than the body and there are nearly translucent hairs sparsely distributed along the length of each foot. The hindfoot is smaller and narrower than in C. monax ; digit 5 is only slightly longer than digit 1. The inner plantar surface is covered by numerous small tubercles ( Fig. 7 ), as in C. monax .

The skull of C. newmarki is small ( Table 4) and wedgeshaped with a rounded braincase and a moderate lambdoidal crest. It is smaller than any of the other OTUs considered in this study, except for C. mdumai . It is also considerably smaller than true C. montis from Rwenzori Mountains ( Table 5). The lateral profile of the skull is straight and slightly rounded towards the braincase. The first upper incisor is short and slender, barely reaching as low as the tip in I 2. The upper unicuspids are narrow and have small cingula. The last upper molar (M 3) is robust, but smaller than in C. montis ( Table 5).

Distribution: Known only from Mt Meru, Tanzania ( Demeter & Hutterer, 1986; Dippenaar & Meester, 1989), at elevations between 1800 and 3600 m. Dippenaar & Meester (1989) and Hutterer & Dieterlen (1981) listed specimens from Kilimanjaro (West) and various places in Kenya and Sudan as C. montis , but these have to be restudied. The distribution maps of C. montis in Dippenaar & Meester (1989) and Hutterer (2013) apparently include more than one species.

Etymology: The species is named in honour of Dr William D. Newmark in recognition of his tireless conservation efforts and long-term study of the Tanzanian biota, with an emphasis on the East and West Usambara Mountains. We suggest the common name Newmark’s shrew.

Ecological notes: Crocidura newmarki is syntopic with C. allex and C. hildegardeae in the montane habitats of the eastern slopes of Mt Meru. Interestingly, the soricid species diversity appears to be much lower on Mt Meru than similar habitats in neighbouring Mt Kilimanjaro (Stanley, unpubl. data), where at least five different species and three different genera occur (see C. monax account). In a faunal survey in 2009 (Stanley, unpubl. data), Crocidura newmarki was found between 1950 and 3600 m in habitats ranging from submontane forest to the ericaceous zone above the treeline. Females made up 38% of the total number of C. newmarki sampled in 2009 along the south-eastern slope of Mt Meru.

Figures

Figure 7. Plantar view of the right hindfoot of (A) Crocidura monax (FMNH 173789), (B) C. newmarki sp. nov. (FMNH 208012) and (C) C. munissii sp. nov. (FMNH 158407); scale is 5 mm. Note differences in the relative distance between thenar (T), hypothenar (H) and interdigital pads (I1–4).

Figure 9. Lateral views of the first upper incisor of populations of the C. monax species group; scale is 1 mm: A, Ngorongoro FMNH 211332 (= C. mdumai sp. nov.); B, Uluguru FMNH 158280 (= C. munissii sp. nov.); C, Udzungwa FMNH 155501 (= C. munissii sp. nov.); D, Ruhebo FMNH 197660 (= C. munissii sp. nov.); E, Ukaguru FMNH 166705 (= C. munissii sp. nov.); F, Meru FMNH 208424 (= C. newmarki sp. nov.); G, Kilimanjaro FMNH 174109; H, North Pare FMNH 192665 (= C. monax); I, South Pare FMNH 153918; J, Magamba FMNH 27429 (= C. usambarae); K, West Usambara FMNH 151099; L, East Usambara FMNH 149970 (= C. tansaniana).

Figure 12. Dorsal, ventral and lateral views of adult cranium and mandible of Crocidura newmarki [FMNH 208439 (holotype); CI = 20.59 mm], a male from Mt Meru, Arusha National Park, near Saddle Hut (3600 m).