Trilacuna simianshan Tong & Li

Tong, Yanfeng, Guan, Xijin & Li, Shuqiang, 2018, Two new species of the genus Trilacuna from Chongqing, China (Araneae, Oonopidae), ZooKeys 771, pp. 41-56 : 41

Trilacuna simianshan Tong & Li sp. n. Figs 1, 2, 3, 4, 5

Type material.

Holotype ♂ (SYNU-99), China, Chongqing Municipality, Jiangjin Dist., Simianshan Natural Reserve, Dawopu, 28°35'14.628"N, 106°22'44.790"E, 1000 m, 20.X.2014, leg. Y. Tong. Paratypes: 1 ♂, 2 ♀ (SYNU-99), same data as holotype; 1 ♂, 2 ♀ (IZCAS Ar-25089), same data as holotype; 2 ♀ (SYNU-100), China, Chongqing Municipality, Jiangjin Dist., Simianshan Natural Reserve, Dawopu, 28°34'43.956"N, 106°21'2.424"E, 28 m, 20.X.2014, leg. Y. Tong.

Etymology.

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

Diagnosis.

This new species is similar to T. rastrum and can be distinguished by two long outgrowths of the embolus system and the long cone-shaped structure in females vs. the embolus system with a short ribbon-like outgrowth and a rake-shaped protuberance, and a simple stick-shaped sclerite centrally on the female genitalia of T. rastrum (see Tong and Li 2007: figs 6-10).

Description.

Male. Body yellow-brown, chelicerae and sternum lighter, legs yellow. Habitus as in Fig. 1 A–C. Body length 2.21; carapace 1.13 long, 0.86 wide; abdomen 1.16 long, 0.75 wide. Carapace sides granulate; lateral margin rebordered, with a row of short, fine hairs and small blunt denticles. Six eyes, well developed, arranged in a compact group; ALE, PME subequal, larger than PLE; ALE–PLE separated by less than ALE radius, PME touching each other; posterior row recurved from above, procurved from front (Fig. 1D, G). Clypeus sinuous in frontal view, anterior lateral eyes separated from edge of carapace by about 2.0 times their diameter, with needle-like setae. Mouthparts: chelicerae straight, proximal region with one hair with elevated hair base (ehb); labium rectangular, anterior margin deeply incised (ldi) (Fig. 1E); endites slender, distally branched (sdb) (Fig. 1E). Sternum with radial furrows between coxae I–II, II–III, III–IV; surface strongly rugose on radial furrows and middle area; setae sparse, light, needle-like, evenly scattered (Fig. 1E). Abdomen: booklung covers large, ovoid, surface smooth (Fig. 2B). Dorsal scutum not fused to epigastric scutum. Apodemes present, posterior spiracles connected by a shallow groove (Fig. 2A). Leg spination (all spines longer than segment width): legs I-II: tibia: v2-2-2-2-0, metatarsus: v2-2-0. Trichobothria: tibia: each with three; metatarsus: each with one.

Genitalia. Epigastric region with sperm pore (sp) small, oval, rebordered, situated between anterior spiracles; with a small hole (slh) between the posterior spiracles (Fig. 2A). Palp (Figs 2C, D, 3): orange. 0.46 long (0.15, 0.08, 0.11, 0.12). Femur strongly swollen (width/length = 0.09/0.15) (Fig. 2C, D). Bulb oval, stout, tapering apically. Embolus system (Fig. 3B, D, F) complex, with two long, strongly curved outgrowths (ogr1 and ogr2); the surface of the embolus system bearing numerous small “papillae”. The base of the embolus system with a wing-like, membranous projection (mp) in prolateral view and a circular projection (cp) covered with scales in retrolateral view; middle part of the embolus system with a rectangular projection (rp) in dorsal view.

Female. As in male except as noted. Slightly larger than male. Body length 2.28; carapace 0.99 long, 0.85 wide; abdomen 1.36 long, 0.89 wide. Postepigastric scutum long. Posterior spiracles connected by groove (Fig. 5B).

Female genitalia. Ventral view (Fig. 5H): Middle part of posterior margin of epigastric scutum much extended posteriorly (pe); surface without external features. Dorsal view (Fig. 5I): with a very long, nearly cone-shaped structure (css), at the posterior end of the cone-shaped structure is a slender line-like structure (sls) originating and extending anteriorly. Transverse bars with two relatively long, lateral apodemes.

Distribution.

China (Chongqing).