Spinirta quadrata sp. nov. (ĤḦẊĦ)

Figs 3F, 18–19

Type material. Holotype: ♂, CHINA: Hubei Municipality, Shennongjia, Guanmen Mountain (31°26.182′N, 110°22.845′E), 1366 m a.s.l., 18 August 2010, leg. Junfang Hu.

Etymology. The specific name is from the Latin word quadrata, meaning “square”, referring to the RTA that is square in ventral view.

Diagnosis. The male can be distinguished from other congeners by: 1) The ventral view of the outer edge of RTA is square (Figs 3F, 18E, I); 2) the main branch of the embolus with a fin-like protrusion ventrally (Fig. 18F, H). Female unknown.

Description. Male (Figs 3F, 18–19). Holotype: body 8.55 long; carapace 4.00 long, 3.21 wide, width: length = 0.80; abdomen 4.55 long, 2.71 wide. Diameters of eyes: AME 0.25, ALE 0.19, PME 0.24, PLE 0.25. Eye interdistances: AME–AME 0.14, AME–ALE 0.10, ALE–ALE 0.82, PME–PME 0.25, PME–PLE 0.27, PLE–PLE 1,21, ALE–PLE 0.12. OAW 1.51, CRW 1.94, OAW/CRW = 0.78. MOA 0.55 long, front width 0.62, back width 0.69. Clypeus height 0.30, 1.20 times AME diameter. Chelicerae with three promarginal teeth and five retromarginal teeth. Labium 0.66 long, 0.56 wide. Sternum 1.91 long, 1.79 wide. Measurements of legs: leg I 12.00 (3.29 + 1.39 + 2.88 + 2.74 + 1.70), II 11.08 (2.99 + 1.29 + 2.68 + 2.46 + 1.66), III 9.88 (2.81 + 1.19 + 2.11 + 2.38 + 1.39), IV 13.14 (3.67 + 1.25 + 3.01 + 3.78 + 1.43).

Palp as illustrated (Figs 3F, 18 E–I, 19). Tibial ventral hump large, with round tip. RTA outer edge square; ventral surface with relatively sparse short coniform spines. PTA triangular. Tegulum retrolateral apex round. Subtegulum with two inclined parallel grooves on prolateral surface. Embolus longer than embolar apophysis, slab-like, with pointed tip, prolateral surface with file-like grooves, ventrally with sharp fin-like protrusion; embolar apophysis short, digitiform, smooth.

Distribution. China (Hubei) (Fig. 26).