Neodon konggordous Wang & Liu, 2025

Wang, Xuming, Pan, Xuan, Liu, Yingxun, Murphy, Robert W., Peng, Buqing, Duan, Chao, Liao, Rui, Wang, Xin & Liu, Shaoying, 2025, Three new species of Neodon (Rodentia, Cricetidae) from Sichuan and Xizang, China, Zoosystematics and Evolution 101 (3), pp. 999-1012 : 999-1012

Neodon konggordous Wang & Liu sp. nov.

Note.

Unnamed clade N. sp 3

Holotype.

An adult female, field number XZ 23131 (Museum number SAF 230511 ), collected from Cuona (CoNa) County, Xizang (Tibet), by Xuming Wang on August 19, 2023 . Specimen, prepared as a skin with a cleaned skull, was deposited at the Sichuan Academy of Forestry.

Type locality.

West of Konggordo Mountains , Cuona County, Xizang, China; 27.923734°N, 91.838384°E; 3,870 m a. s. l.

Measurements of holotype.

Weight, 43 g; HBL, 120 mm; TL, 43 mm; HFL, 21 mm; EL, 15 mm; SGL, 27.83 mm; SBL, 26.27 mm; CBL, 27.36 mm; ZB, 15.46 mm; IOW, 3.58 mm; MB, 12.88 mm; SH, 9.92 mm; ABL, 7.67 mm; LMxT, 6.56 mm; LMbT, 6.51 mm; M-M, 5.57 mm; ML, 19.94 mm; and LEPILM, 9.18 mm.

Paratypes.

Ten specimens (8 ♂♂, 2 ♀♀), consisting of skins with skulls and male specimens with prepared glans penis. All specimens (XZ 23072 [ SAF 230456 ], ♂; XZ 23078 [ SAF 230462 ], ♂; XZ 23080 [ SAF 230460 ], ♂; XZ 23081 [ SAF 230465 ], ♂; XZ 23103 [ SAF 230483 ], ♂; XZ 23110 [ SAF 230490 ], ♂; XZ 23130 [ SAF 230510 ], ♂; XZ 23131 [ SAF 230511 ], ♀; XZ 23133 [ SAF 230513 ], ♀; and XZ 23134 [ SAF 230514 ], ♂) were collected from the type locality by Xuming Wang, Rui Liao, and Buqing Peng.

Geographic distribution.

Known only from the western Konggordo Mountains, on both sides of the Dawang River (Tawang Chu) and Niangjiang Qu (Nyamjang Chu).

Etymology.

The name is derived from the Konggordo Mountains. Common names: Konggordo Mountain Vole, 康格多松田鼠 (Kanggeduo Songtianshu).

Diagnosis.

An arvicoline with the typical Neodon palate. Average adult HBL about 120 mm, with a TL of approximately 40 % of the HBL. First lower molar with three closed triangles in front of posterior transverse space and six inner and five outer angles. Second upper molar lacking posterior inner angle, forming three inner and three outer angles. Third upper molar with four inner and three outer angles. Neodon shergylaensis , N. nanchabarwaensis , and N. nyalamensis similar to N. konggordous sp. nov. in TL - to- HBL ratio and tooth morphology. Compared to N. shergylaensis , with first lower molar having six inner and four outer angles, N. nanchabarwaensis , N. nyalamensis , and N. konggordous sp. nov. with a first lower molar with six inner and five outer angles. First upper molar of both N. nanchabarwaensis and N. konggordous sp. nov. with four inner and three outer angles, and 80 % of individuals of N. nyalamensis with four inner and four outer angles. Body size of N. nyalamensis smaller than that of N. nanchabarwaensis and N. konggordous sp. nov. Anterior cap at front of first lower molar in N. konggordous sp. nov. usually forms a standard circular arc with smooth circular lines at the outer edge, but that of N. nanchabarwaensis with an irregular outer margin. Further, first pair of triangles behind the most anterior transverse prism of third upper molar of N. nanchabarwaensis connected, but N. konggordous sp. nov. with two unconnected closed triangles.

Description.

General pelage color of the holotype black-brown, back darker, and sides lighter. Fur thick, about 14 mm long, proximal part black-gray, but distal part brown or black. Color boundary between the dorsal and ventral fur indistinct. Ventral side gray-white with black-gray base; coloration from the throat to belly and anus uniform. Pelage of paratypes the same as that of holotype. Mystacial vibrissae mostly white, but some with white proximal parts and black distal parts, approximately 25 on each side, shortest approximately 5 mm, and the longest was approximately 28 mm. Ears projected clearly above pelage, rim on front and entire backside covered with dense black-gray fur, edge with white fur. Dorsal part of the tail black-brown, ventral slightly lighter, without distinct color boundary. Pelage of forelimb and hindlimb gray-white. Claws yellow-white, with long, stiff hair (Fig. 4 B 1 – B 3 ). Five palmar and plantar pads. Females with two pectoral pairs and one inguinal pair of mammae. Skull sturdy (Fig. 5 B ), straight in dorsal profile. Nasal broad anteriorly, narrow posteriorly. Frontal broad at posterior and anterior ends, constricted in middle. Interparietal broad and nearly trapezoidal. Distinct ridges in interorbital space of adult specimens; two ridges form a crest. Two faint ridges behind the temporal joint, above the auditory bulla. Zygomatic arches robust, and auditory bullae relatively large. Posterior palate characteristic of Arvicolinae , continuing as a narrow bridge that separated both lateral pits. Numerous small foramina present in palatines and pterygoids. Mandibles sturdy. Upper incisors straight, projected downward, lip-side surfaces colored orange. First upper molar with three closed triangles posterior to anterior transverse space (two inner and one outer) and a posterior inner angle, forming four inner and three outer angles. Second upper molar with two closed triangles posterior to anterior transverse space (one inner and one outer) and a posterior inner angle, forming three inner and three outer angles. Third upper molar with three closed triangles posterior to anterior transverse space (one inner and two outer) and a C-shaped loop, forming four inner and three outer angles. Lower incisors relatively long, with orange lip-side surfaces. First lower molar with three closed triangles (two inner and one outer) in front of posterior transverse space, with two pairs of connected triangles in front. Anterior space semi-circular, typically forming a standard circular arc with a smooth outer edge. Molar with six inner and five outer angles. Second lower molar with three inner and three outer angles. Third lower molar with three irregular transverse lobes, forming three inner and three outer angles. Glans penis (Fig. 6 B ) robust, exterior stick-shaped, with ventral groove and 2–5 small outer crater papillae on each side of the lateral flap. Urethral lappet with three branches, middle branch very short with distal part enlarged. Conical dorsal papillae with two cusps arranged anterior-posteriorly. Proximal, distal, and lateral baculum bony; distal part of proximal baculum enlarged and pestle-shaped; basal part enlarged, tapering to a distal point, with a concave terminal end. Lateral baculum slender, with an enlarged basal part.

Habitat.

This species inhabited alpine scrubs, subalpine coniferous forests, mixed coniferous broad-leaved forests, and secondary shrubs, artificial tea gardens, and other habitats, occupying a wide elevation spanning 2,810 –4,350 m. Sympatric species include Soriculus nigrescens , Niviventer eha , N. gladiusmaculus , Micromys erythrotis , and Ochotona macrotis .

Figures

Figure 4. Dorsal, ventral, and lateral views of N. kulakangria sp. nov. (A 1 – A 3), N. konggordous sp. nov. (B 1 – B 3), and N. minor sp. nov. (C 1 – C 3).

Figure 5. Dorsal, ventral, and lateral views of the skull and dorsal and lateral views of the mandible of N. kulakangria sp. nov. (A), N. konggordous sp. nov. (B), and N. minor sp. nov. (C).

Figure 6. Penis of N. kulakangria sp. nov. (A), N. konggordous sp. nov. (B), and N. minor sp. nov. (C). Numbered structural features are as follows: 1. penis; 2. midventral cut view of glans; 3. urethral papilla; 4. dorsal papilla. Lowercase letter structural features are as follows: a. distal baculum; b. outer crater papillae; c. outer crater; d. urethral papilla; e. ventral groove; f. glans; g. prepuce; h. body of penis; i. tip of distal baculum; j. site of dorsal papilla; k. lateral baculum; l. proximal baculum; m. the base of proximal baculum.