Spinirta gen. nov., a new dark sac spider genus from southern China (Araneae: Corinnidae) Author Jin, Chi 0000-0002-4694-4870 College of Landscape and Ecological Engineering, Hebei University of Engineering, Handan, Hebei 056038, P. R. China. jinchi _ spider @ 163. com; https: // orcid. org / 0000 - 0002 - 4694 - 4870 & The Key Laboratory of Zoological Systematics and Application, College of Life Sciences, Hebei University, Baoding, Hebei 071002, P. R. China Author Zhang, Feng The Key Laboratory of Zoological Systematics and Application, College of Life Sciences, Hebei University, Baoding, Hebei 071002, P. R. China text Zootaxa 2020 2020-08-27 4838 3 301 330 journal article 8680 10.11646/zootaxa.4838.3.1 a3d37dde-cd1c-46a3-8727-b3140740562e 1175-5326 4403970 112D4DC3-723A-4216-A608-3D03B392E973 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. FIGURE 18. Spinirta quadrata sp. nov. : A. male habitus, dorsal view; B. same, ventral view; C. male ocular area, dorsal view; D. male cephalothorax, frontal view; E. RTA, ventral view; F. male left palp, prolateral view; G. same, ventral view; H. same, retrorolateral view; I. same, dorsal view. 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). FIGURE 19. Spinirta quadrata sp. nov. : A. male left palp, prolateral view; B. same, ventral view; C. same, retrorolateral view; D. same, dorsal view. 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 ).