Mallinella acutidentata Zhang & Zhang sp. nov.

Figures 9–11, 15

Type material. Holotype ♂ (MHBUARA-2024-882-1), CHINA: Yunnan, Yingjiang County, Tongbiguan Town, 24.6680°N, 97.5990°E, 913.4 m elev., 5 October 2024, leg. K. Yu, Y. Ni. Paratypes. 14♂ 1♀ (MHBUARA-2024- 882-2–16), same data as holotype.

Etymology. The specific epithet is a combination of the Latin words ‘ acutus ’ (meaning sharp) and ‘ dentata ’ (meaning toothed), referring to the sharp basal tooth on the tegular apophysis of this species; adjective.

Diagnosis. This new species resembles Mallinella yadong Wang, Mu, Lu, Xu & Zhang, 2024 in having a similarly shaped tegular apophysis, retrolateral tibial apophysis, conductor, epigynal plate and copulatory duct (see Wang et al. 2024: 57, figs 8A–F, 9A–B), but the male can be distinguished by: 1) the presence of a mesal ridge on tegular apophysis (Figs 10B–C, 11B–C vs. with a mesal ridge and a meso-retrolateral fold in M. yadong); 2) tegular apophysis with triangular basal tooth and sharp apex in ventral view (Figs 10B, 11B, vs. trapezoid, with a rounded apex in ventral view in M. yadong); 3) mesal branch of embolus shorter than lateral one (Figs 10A, 11A, vs. lateral branch shorter than mesal one in M. yadong). The female differs from M. yadong by: 1) the presence of a triangular elevation on posterior margin of epigynal plate (Figs 10D, 11D, vs. the posterior margin smooth, without elevation in M. yadong); 2) tubular spermatheca with a length about three times its width (Figs 10E, 11E, vs. oval, length about 1.5 times its width in M. yadong).

Description. Male (holotype, Figs 9A‒B): total length 8.02; carapace 4.22 long, 3.06 wide; abdomen 3.80 long, 2.65 wide. Carapace ovoid, dark brown. Fovea longitudinal, reddish brown. Eye sizes and interdistances: AME 0.20, ALE 0.21, PME 0.18, PLE 0.21; AME‒AME 0.13, AME‒ALE 0.19, ALE‒ALE 0.78, PME‒PME 0.17, PME‒PLE 0.38, PLE‒PLE 1.05, ALE‒PLE 0.06. MOA 0.63 long, anterior width 0.56, posterior width 0.51. CH 1.24. Chelicerae dark brown, without teeth on margins. Endites yellowish-brown, with anterior brush of black hairs. Labium triangular, dark brown. Sternum 1.61 long, 1.64 wide, yellow, margin brown, anterior margin nearly straight, lateral margin with sharp extensions fitting in coxal concavities. Leg measurements: Ⅰ 11.61 (3.02, 1.15, 2.56, 2.95, 1.93), II 10.44 (2.74, 1.11, 2.13, 2.73, 1.73), III 10.34 (2.72, 1.15, 2.02, 2.93, 1.52), IV 13.22 (3.29, 1.21, 2.68, 3.92, 2.12); leg formula 4123. Abdomen dorsal grey, anterior portion with a narrow, longitudinal scutum and two white patches, posterior portion with two pairs of white spots, one transverse stripe, one longitudinal stripe and one inverted triangle patch.

Palp (Figs 10A‒C, 11A‒C). RTA finger-shaped, pointing ventrad. VTA semi-circular, about 1/3 of RTA length. Cymbial fold 1/2 of cymbium width and 1/3 of cymbium length. Tegular tubercle triangular. Tegular apophysis with a distinct mesal ridge, apico-prolateral process fan-shaped, basal tooth triangular, 1/3 of tegular apophysis length. Conductor beak-shaped, with a sharp and ventrally pointing branch and a semicircular dorsal process. Embolus bifurcating at distal 1/3 portion, lateral branch twice width of mesal branch.

Females (paratype, HBUARA#2024-882-2, Figs 9C–D): total length 8.19, carapace 4.04 long, 2.65 wide; abdomen 4.15 long, 3.00 wide. Eye sizes and interdistances: AME 0.14, ALE 0.19, PME 0.17, PLE 0.20; AME ‒ AME 0.11, AME ‒ ALE 0.20, ALE ‒ ALE 0.78, PME ‒ PME 0.19, PME ‒ PLE 0.38, PLE ‒ PLE 1.05, ALE ‒ PLE 0.09. MOA 0.58 long, anterior width 0.49, posterior width 0.52. CH 1.27. Leg measurements: I 8.62 (2.20, 0.93, 2.00, 1.93, 1.56), II 8.12 (2.19, 0.93, 1.73, 1.87, 1.40), III 8.58 (2.08, 1.02, 1.59, 2.14, 1.75), IV 10.41 (2.41, 1.05, 2.17, 3.03, 1.75); leg formula 4132. Sternum 1.55 long, 1.50 wide. Coloration and patten same as male.

Epigyne (Figs 10D‒E, 11D‒E). Epigynal plate small, nearly trapezoidal, with a triangular elevation on posterior portion. Copulatory opening hidden in a groove. Spermatheca tubular, apical part with a spherical projection. Copulatory duct thin. Fertilization ducts slender, invisible in dorsal view.

Variation. The total length in male specimens examined ranges from 8.02 to 9.37 (n = 15).

Distribution. Known only from the type locality (Fig. 15).