Trilacuna difeng Wang & Tong & Bian & Li 2021, sp. nov.

Trilacuna difeng Tong & Li, sp. nov.

Figs 1, 2 A–D, 3, 4, 5A–B, 9

Type material. Holotype: Male (SYNU-264), Difeng National Park (26º10'45.93''N, 105º28'44.886''E, elevation 1438 m), Fengjie County, Chongqing Municipality, China, 23 October 2014, S. Lyu and Y. Tong leg. Paratypes: 2 males (SYNU-265–266) and 3 females (SYNU-267–269), same data as holotype. Other materials examined: 1 male (SYNU-270) and 3 females (SYNU-271–273), same data as holotype.

Etymology. The specific name is a noun in apposition from the type locality.

Diagnosis. This new species is similar to Trilacuna gongshan Tong, Zhang & Li, 2019, but males can be distinguished by the broad sickle-shaped branch of embolus system (Fig. 3E, H), and females by the large globular structure of the endogyne (Fig. 5B). T. gongshan males have three long, tooth-like lobes of embolus system, and females have a very small globular structure of endogyne (Tong et al. 2019: figs 11B, D, 24H).

Description. Male (holotype, SYNU-264). Body yellow, chelicerae and sternum lighter. Habitus as in Fig. 1A, C, E. Body length 1.97; carapace 0.93 long, 0.76 wide; abdomen 1.03 long, 0.68 wide. Carapace sides granulate; lateral margin rebordered. Six eyes, well developed, arranged in a compact group; ALE, PME and PLE subequal; ALE-PLE separated by less than ALE radius, PME touching each other; posterior row recurved from above, procurved from front (Fig. 1B, I). Clypeus sinuous in frontal view, anterior lateral eyes separated from edge of carapace by about 1.4 times their diameter. Mouthparts: chelicerae straight, proximal region with one hair with elevated hair base; labium rectangular, anterior margin deeply incised (Fig. 1D); endites slender, distally strongly branched (Fig. 1D). Sternum with radial furrows between coxae I-II, II-III, III-IV; surface medially strongly reticulated (Fig. 1D). Abdomen (Fig. 1G, H): booklung covers ovoid, surface smooth; dorsal scutum not fused to epigastric scutum; apodemes present, posterior spiracles not connected; sperm pore oval, situated between anterior and posterior spiracles. Leg spination (all spines longer than segment width): legs I-II: tibia: v2-2-2-2-0, metatarsus: v2-2-0. Palp (Figs 2 A–D, 3): orange; 0.62 long (0.19, 0.14, 0.14, 0.15); femur greatly swollen (width/length = 0.68); bulb oval, tapering apically; embolus system (Fig. 3E, F, H) with a broad sickle-shaped branch (ssb) in prolateral view, a median branch (mb) in dorsal view, and a lateral curved branch (lb) in retrolateral view.

Female (SYNU-267): Same as male except as noted. Habitus as in Fig. 4A, C, E; slightly larger than male. Body length 2.02, carapace 0.91 long, 0.76 wide, abdomen 1.15 long, 0.72 wide. Endites: unmodified. Epigastric area (Figs 4G, 5A): surface without external features. Endogyne (Fig. 5B): with narrow, transverse sclerite (tsc), an anterior stick-shaped sclerite (as), and a posterior large globular structure (glo); transverse bar (tba) with two lateral apodemes (ap).

Distribution. Known only from the type locality (Fig. 9).