Sorex nivicola Bannikova, Jenkins, Lebedev, Pavlova, Sheftel, 2025

Bannikova, Anna A., Jenkins, Paulina D., Lebedev, Vladimir S., Pavlova, Svetlana V., Yakushov, Vasily D., Raspopova, Alexandra A., Zhu, Yongke, Fang, Yun, Sun, Yue-Hua & Sheftel, Boris I., 2025, The morphological, chromosomal and molecular illumination of the dramatic diversity of the stripe-backed shrews, Sorex cylindricauda species complex (Eulipotyphla: Soricidae), Vertebrate Zoology 75, pp. 227-243 : 227-243

Sorex nivicola Bannikova, Jenkins, Lebedev, Pavlova, Sheftel sp. nov.

Holotype.

ZMMU S-207218 (field number G 18-87), GenBank [ PV 240087 , PV 201067 , PV 201094 , PV 239965 ], collectors: Lebedev V., Zhu Y., juvenile male, skin and skull, weight 7.5 g, head and body length 71 mm, tail length 53 mm, hind foot length 13 mm.

Type locality.

CHINA, Gansu Province, Luqu County, Langmusi ; 34.0789°N 102.634°E.

Paratypes.

S-207219 (G 18-96) GenBank [ PV 240088 , PV 201068 , PV 201095 , PV 239966 ] • juvenile female, skin and skull ; S-207220 (G 18-104) GenBank [ PV 240089 , PV 201069 , PV 201096 , PV 239967 ] • adult female, skin and skull ; S-207221 (G 18-116) GenBank [ PV 240085 , PV 201070 , PV 201097 , PV 239968 ] • juvenile male, skin and skull ; S-207222 (G 18-117) GenBank [ PV 240090 , PV 201071 , PV 201098 , PV 239969 ] • juvenile female, skin ; S-207223 (G 18-119) GenBank [ PV 240091 , PV 201072 , PV 201099 , PV 239970 ] • juvenile female, skin and skull ; S-207224 (G 18-120) GenBank [ PV 240092 , PV 201073 , PV 201100 , PV 239971 ] • juvenile male, skin and skull . All from the same locality as the holotype.

Other material.

S-195208 (Chi 11-96) GenBank [ MH 332013 , PV 240034 , PV 201086 , PV 239957 ] adult female, skin and skull, from S Gansu, Taizishan Nature Reserve , 35.2667°N, 103.4333°E ; NHMUK 1912.8. 5.11 female, skin and skull, Gansu, 17 miles [27.4 km] S. E. Tao-chou [ Lintan ], 800–900 ft [244–275 m], c. 34.6667°N 103.3833°E ; S 207225 (G 18-146) GenBank [ PV 240067 , PV 201075 , PV 201102 , PV 239972 ] juvenile male, skin ; S-207226 (G 18-174) GenBank [ PV 240086 , PV 201076 , PV 201103 , PV 239973 ] juvenile male, skin ; S-199343 (G 17-75) GenBank [ PV 239985 , PV 201083 , PV 201110 , PV 239974 ] juvenile male, skin and skull from Sichuan, 16 km E from Ruoergai (= Zoigê ) 33.5847°N 103.1453°E .

Diagnosis.

Defined by a combination of characters. Large sized shrew, dorsal stripe present. Skull with narrow interorbital region relative to maxillary breadth. Upper unicuspids with Un 2 larger than Un 3, Un 5 broad, similar in size to Un 4.

Etymology.

The name is derived from the Latin nivis – snow, with the suffix - cola – dweller. The name is treated as a noun in apposition even though the generic name is masculine.

Description.

Skin (Fig. 8 A ): Dorsal pelage brown with a conspicuous to inconspicuous darker dorsal stripe (4–6 mm wide); dorsal pelage colour grading in the lateral region into the lighter brown of the ventral pelage. Dorsal pelage dark grey at the base, the upper portion of the hairs pale brown, with some darker brown at the tips; ventral pelage dark grey at the base, pale drab brown at the tips. Tail brown dorsally, clearly demarked from the pale brown ventral colour. Tail with pencil of hairs at the tip (4–5 mm). Dorsal surface of feet light in colour. Two pairs of inguinal mammae are present on the adult female S-207220 . — Skull (Fig. 5 A ): Skull large, upper toothrow relatively long, narrow interorbital region relative to maxillary breadth. — Dentition (Fig. 5 B ): Un 5 clearly visible in toothrow in labial view although slightly obscured by anterobuccal cingulum of P 4; slightly less than 0.5 height of parastyle of P 4. In occlusal view, Un 5 similar in size to Un 4 with a broad posterolingual cingulum; breadth equivalent to or slightly less than distance between parastyle and base of protocone of P 4.

Comparison with other species.

Sorex nivicola sp. nov. is larger in body size than S. cansulus and S. wardi . The head and body length of S. nivicola sp. nov. is slightly greater than in S. sinalis but comparable to S. cylindricauda . — Skin: The presence of a dorsal stripe in S. cylindricauda , S. wardi and S. nivicola sp. nov. (Figs 8 , 9 ), serves to distinguish these three species from S. cansulus , S. excelsus and S. sinalis . — Skull: The skull of S. nivicola sp. nov. is similar in size to that of S. sinalis and S. cylindricauda (Fig. 5 A ) but notably larger than that of S. cansulus and S. wardi (Table 1 ). Sorex nivicola sp. nov. is distinguished from S. sinalis and S. cylindricauda by the longer toothrow, greater maxillary breadth and greater mandible length. The rostrum of S. nivicola sp. nov. is generally longer and broader than that of S. sinalis and on average longer than in S. cylindricauda . The ratio of interorbital breadth to maxillary breadth is on average lower and mandible height greater than in S. cylindricauda . — Dentition: The relatively large size of Un 5 in S. nivicola sp. nov., S. cylindricauda and S. bedfordiae distinguishes these species from S. sinalis and S. cansulus in both of which Un 5 is much smaller than Un 4. The size of Un 5 relative to Un 4 differs in all three of the larger species (Fig. 5 B ). In labial view, Un 5 of S. nivicola sp. nov. and S. cylindricauda is clearly visible in the toothrow, whereas in S. sinalis Un 5 is visible but partially obscured by the parastyle of P 4. In occlusal view, Un 5 is noticeably smaller and narrower than Un 4 in S. sinalis and narrower than the distance between the parastyle and protocone of P 4; in S. nivicola sp. nov. Un 5 is similar in size to Un 4 and slightly less or equivalent in breadth to the distance between parastyle and protocone of P 4; in S. cylindricauda Un 5 is as large or larger than Un 4 and nearly as broad or broader than the distance between the parastyle and the protocone of P 4. Sorex nivicola sp. nov. differs from S. cylindricauda and S. wardi in the relative size of the second and third unicuspids; Un 2 is larger than Un 3 in S. nivicola sp. nov., whereas Un 3 is larger than Un 2 in S. cylindricauda and S. wardi .

Distribution.

Sorex nivicola sp. nov. is known from SW Gansu, NW Sichuan, E Qinghai. This species mostly lives in high mountain shrubland and grasslands at altitudes of 3400–4500 m (although it can also be found at elevations of just 2500 m). It primarily inhabits stony valleys of small streams covered with bushes.

Sorex sinalis – remains unexplored genetically. This species is known only from the type series collected in the high-altitude belt> 3000 m asl in the Qinling mountains (72.4 km S. E. of Fengxiang, Shaanxi) ( Thomas 1912). As of now, the only genetically analysed Sorex from the nearby mountains belong to S. wardi . Having examined the type material, Dolgov (1985) concluded that S. sinalis is conspecific with S. isodon , a species which belongs to different species group including also S. cansulus , S. unguiculatus and S. caecutiens ( Bannikova et al. 2018) . The same view was previously maintained by Corbet (1978). However, Hoffmann (1987) disagreed with Dolgov and rejected conspecificity of isodon and sinalis . We believe that the status and phylogenetic position can be established either by the analysis of the type specimens or de novo sampling in the high-altitude zone of Qinling.

Figures

Figure 5. A Comparison of skulls from left to right of Sorex cylindricauda NHMUK 1911.9. 8.14 from Sichuan, Yingjing, the holotype of S. sinalis NHMUK 1912.8. 5.3 from Shaanxi, Feng Siang, and Sorex Tax. K ZMMU S- 207218 (holotype of S. nivicola sp. nov.) from Gansu, Luqu County, Langmusi. Top row dorsal view, middle row ventral view, bottom row left lateral view of skull and mandible. B Upper dentition from left to right of S. cylindricauda NHMUK 1911.9. 8.14, the holotype of S. sinalis NHMUK 1912.8. 5.3 and Sorex Tax. K ZMMU S- 207218 (holotype of S. nivicola sp. nov.). Occlusal view above, left lateral view below.

Figure 8. Dry skins of Sorex nivicola sp. nov. in dorsal and ventral views: A holotype S- 207218 and paratypes: B S- 207222, C S- 207221, D S- 207220.

Figure 9. Dry skins in dorsal and ventral views of Sorex wardi (A) S- 199291 and (B) S- 207194; Sorex aff. bedfordiae, clade D S- 199290 (C), S. cylindricauda S- 207217 (D).