Tmarus ungulatus, Chen & Liu & Hu, 2025

Tmarus ungulatus sp. nov.

Figs 1B View FIGURE 1 , 5–7 View FIGURE 5 View FIGURE 6 View FIGURE 7

Type material. Holotype: ♂ ( QZMS02691 ), CHINA : Hubei Province: Enshi Tujia and Miao Autonomous Prefecture , Xuan’en County, Qizimeishan National Nature Reserve , Shadaogou Town , Xueluozhai Forest Farm ; 29.74721°N, 109.74536°E; 1338 m; 19 July 2023; Changhao Hu and Mian Wei leg. GoogleMaps Paratypes: 2♂, 2♀ ( QZMS05459–05462 ), with the same data as for holotype GoogleMaps .

Etymology. The specific name is derived from the Latin ungula (meaning “claw”), referring to the claw-shaped tibia in basal-retrolateral view; adjective.

Diagnosis. Tmarus ungulatus sp. nov. belongs to the stellio group ( Logunov 1992), which is characterized by the following morphological characteristics: male palp with a stout embolus arising from tegulum at 12 o’clock position, palpal tibia with conical RTA in dorsal position (= DTA in Logunov 1992 and Ono 1988) and epigyne with short and simple copulatory ducts in parallel run. Within the eastern Asian species of the stellio group, Tmarus ungulatus sp. nov. resembles T. makiharai Ono, 1988 (cf. Fig. 5 View FIGURE 5 and figs 109–111 in Ono 2009, figs 3B, C in Tanikawa 2024), but males can be distinguished by: 1. tibia with three apophysis (vs. four in T. makiharai ); and 2. embolus straight (vs. slightly curved to 3-shaped in T. makiharai ), females can be distinguished by: 1. epigyne with two low hoods half-covering copulatory openings (vs. without hood in T. makiharai ); and 2. copulatory ducts almost 2/3 the width of spermathecae (vs. almost half the wide of spermathecae in T. makiharai ).

Tmarus ungulatus sp. nov. also resembles T. taishanensis Zhu & Wen, 1981 (cf. Fig. 5 View FIGURE 5 and figs 21, 22, 24, 25 in Danilov 1993), but males can be distinguished by: 1. VTA broader than embolus (vs. almost as thin as embolus in T. taishanensis ); and 2. RTA pointing dorsally retorlaterad (vs. pointing anteriad in T. taishanensis ), female can be recognized by: 1. epigyne without atrium (vs. with an atrium in T. taishanensis ); and 2. copulatory ducts almost 2/3 the width of spermathecae (vs. thinner than half the width of spermathecae in T. taishanensis ).

Description. Male: Total length 4.68. Carapace 1.99 long, 1.89 wide; opisthosoma 3.04 long, 1.49 wide. Eye sizes and interdistances: AME 0.10, ALE 0.20, PME 0.11, PLE 0.15, AME–AME 0.14, AME–ALE 0.12, PME– PME 0.23, PME–PLE 0.33, AME–PME 0.14, ALE–PLE 0.25. Leg measurements: I 10.90 (3.13, 0.85, 2.96, 2.66, 1.30); II 10.81 (3.14, 0.78, 2.93, 2.59, 1.37); III 5.64 (1.81, 0.52, 1.38, 1.22, 0.71); IV 5.85 (2.01, 0.49, 1.48, 1.18, 0.69). Leg formula: 1243.

Palp ( Figs 5A–D View FIGURE 5 ). Tibia almost half the length of cymbium; VTA broad and curved, pointing prolaterad; ITA triangular in basal-retrolateral view with pointed apex; RTA small and pointed, slightly curved. Tegulum oval. Embolus straight, arising from tegulum at 12 o’clock position.

Colouration in ethanol ( Figs 6A–C View FIGURE 6 ). Carapace dark brown, cephalic region and median part light brown, with black spots. Chelicerae, endites and sternum brown. Labium black. Legs light brown, with brown, white and purple spots. Dorsal opisthosoma white, with black transverse markings and brown spots; venter with brown spots, lateral part white. Spinnerets brown.

Female: Total length 4.68. Carapace 2.11 long, 2.11 wide; opisthosoma 2.55 long, 2.07 wide. Eye sizes and interdistances: AME 0.06, ALE 0.16, PME 0.09, PLE 0.16, AME–AME 0.21, AME–ALE 0.21, PME–PME 0.30, PME–PLE 0.41, AME–PME 0.24, ALE–PLE 0.34. Leg measurements: I 9.02 (2,72, 0.83, 2.38, 1.97, 1.12); II 7.59 (2.44, 0.59, 1.94, 1.63, 0.99); III 5.09 (1.51, 0.61, 1.27, 0.93, 0.77); IV 5.52 (1.86, 0.56, 1.30, 1.08, 0.72). Leg formula: 1243.

Epigyne ( Figs 5E, F View FIGURE 5 ). Epigynal field longer than wide, with two low hoods half-covering copulatory openings. Copulatory ducts short, almost as long as spermathecae and 2/3 width of spermathecae. Fertilization ducts arising from spermathecae at inner-lateral part, and terminally curved.

Colouration in ethanol ( Figs 6D–F View FIGURE 6 ). As in male, but generally lighter.

Distribution. Known only from the type locality ( Fig. 7 View FIGURE 7 ).