Sicista weigoldi Jacobi, 1923

Deng, Yu, Liu, Qing, Wang, Xuming, Li, Binbin V., Wang, Jing, Liu, Shuang, Liao, Rui, Liu, Shaoying & Chen, Shunde, 2025, Molecular phylogeny and taxonomy of the Sicista concolor group (Mammalia, Rodentia, Sicistidae) with the description of a new species, Zoosystematics and Evolution 101 (3), pp. 1197-1211 : 1197-1211

Sicista weigoldi Jacobi, 1923

Type locality.

Songpan County, Sichuan Province, China.

Diagnosis.

The tail exhibits a distinct bicolored pattern, with the dorsal surface being brown and the ventral surface slightly lighter, devoid of a tuft of hair at the tip (Fig. 7 c 1 – c 3 ). The palatine foramen in the upper jaw is positioned along the midline of the second upper molar, with the distance between the two foramina not exceeding the width of the incisor foramen (Fig. 6 c 1 – c 5 ).

Remarks.

The glans penis is relatively short and thick, covered with keratinized spines. The urethral opening is not Y-shaped, and the external tissue surrounding the urethral opening forms a U-shape. A shallow groove is present at the base of the dorsal midline, but no lateral grooves are observed. The outer annular layer lacks papillae, and no urethral valves, dorsal projections, or lateral branches are present. The baculum exhibits an ossified, rod-like structure. In most individuals, the tip possesses two lateral wings, resembling a “ cobra hood, ” while in a few individuals, it remains a slender rod, possibly due to incomplete ossification of the cartilage. There is no differentiation between distal and proximal ends, and it tends to curve ventrally. The ventral tip is Y-shaped, with a central longitudinal groove, and an additional groove is present on the dorsal side (Fig. 5 c 1 – c 4 ).

S. weigoldi ( Jacobi 1923) was first discovered in Songpan and is characterized by a distinct bicolored tail, with the dorsal side brown and the ventral side white. It was initially considered a junior synonym of S. concolor ( Allen 1940) . Subsequently, S. weigoldi was often regarded as a subspecies of S. concolor ( Wilson and Reeder 1993; Csekész et al. 2017). However, Lebedev et al. (2019) proposed that it may represent a distinct species due to significant geographic isolation. Based on both molecular and morphological evidence, our results support this hypothesis, thereby elevating it to a valid species.

Distribution.

This species is distributed in areas such as Songpan, Pingwu, and Jiuzhaigou in Sichuan Province, inhabiting moist montane coniferous forests, birch forests, and alpine meadows at elevations between 2000 and 4000 meters.

Figures

Figure 5. Comparison of the glans penis of three species within the S. concolor group. a. Sicista concolor; b. Sicista sp 2; c. Sicista weigoldi. 1. Penis; 2. Midventral cut view of glans; 3. Lateral view of baculum; 4. Dorsal view of baculum. (1) Urethral opening; (2) Outer crater; (3) Glans; (4) Prepuce; (5) Body of penis; (6) Baculum.

Figure 6. Skulls and tooth comparison among species of the S. concolor group. a. Sicista concolor (a 1 – a 6) (museum number: SAF 13331); b. Sicista meiguites sp. nov. (b 1 – b 6) (museum number: SAF 191012); c. Sicista weigoldi (c 1 – c 6) (museum number: SAF 240595).

Figure 7. Pelage and tail comparisons among species of the S. concolor group. a. Sicista concolor (a 1 – a 3) (museum number: SAF 13331); b. Sicista meiguites sp. nov. (b 1 – b 3) (museum number: SAF 191014); c. Sicista weigoldi (c 1 – c 3) (museum number: SAF 240595).