Type material. Holotype ♂, Haikou City, Dongzhaigang Mangrove Nature Reserve, 19°57.113′N, 110°33.983′E, elev. - 2 m, 20.VIII.2007, C.X. Wang leg. (IZCAS); Paratypes (7♂ 8♀). 4♂ 4♀, same data as holotype (IZCAS); 1♂ 3♀, Haikou City, Dongzhaigang Mangrove Nature Reserve, 19°57.113′N, 110°33.983′E, elev. - 2 m, 20.VIII.2007, S. Li leg. (IZCAS); 2♂ 1♀, Ding’an County, Tongren Village, 19°30.953′N, 110°18.904′E, elev. 58 m, 27. VI.2019, L.Y. Wang, T. Yuan, K. Yu & J.X. Zhao leg. (SWUC).
Etymology. The specific epithet refers to the type locality; noun in apposition.
Diagnosis. The new species resembles Z. unciformis Li, Wang & Zhang, 2013 (Li, Wang & Zhang, 2013: 30, figs 5A– E, 6A–H) but differs by the lateral apophysis with two small projections, the inner projection spinelike, the outer projection longer than wide with a sharp tip (Figs 72C–F, 73A–D, 74A–B); in Z. unciformis, the lateral apophysis is sinuous, slightly curved, with a small outgrowth. Terminal apophysis covers embolus in the new species (Figs 72C–F, 73A–D, 74A–B) but not in Z. unciformis. Spermathecae round in the new species (Figs 72G–H, 74C–D) but oval in Z. unciformis.
Description. Male. Total length 0.99–1.39. Holotype (Fig. 72A) total length 1.05. Carapace 0.56 long, 0.40 wide; opisthosoma 0.50 long, 0.33 wide. Carapace uniformly yellow-brown. Eye region black. Eye sizes and interdistances: AME 0.08, ALE 0.08, PME 0.12, PLE 0.09; AME–AME 0.02, AME–ALE 0.02, PME–PME 0.05, PME–PLE 0.04. Clypeus height 0.07. Chelicerae elongate, yellowish brown, with three promarginal and two retromarginal teeth. Labium yellowish brown. Endites yellowish brown. Sternum yellowish brown, with sparse brown setae. Legs yellowish brown. Leg measurements: I 2.57 (0.79, 0.93, 0.39, 0.46); II 2.41 (0.72, 0.82, 0.47, 0.40); III 1.69 (0.50, 0.43, 0.31, 0.45); IV 3.20 (0.91, 1.06, 0.76, 0.47). Opisthosoma brown. Venter yellowish brown.
Palp (Figs 72C–F, 73A–D, 74A–B). Lateral apophysis with two small projections, inner projection spinelike, outer projection longer than wide with sharp tip. Terminal apophysis leaf-shaped with pointed tip. Conductor wide, membranous, with a pointed tip. Embolus stout, covered by terminal apophysis.
Female (paratype, Fig. 72B) total length 1.40. Carapace 0.68 long, 0.49 wide; opisthosoma 0.65 long, 0.49 wide. Eye sizes and interdistances: AME 0.07, ALE 0.08, PME 0.13, PLE 0.09; AME–AME 0.02, AME–ALE 0.02, PME–PME 0.05, PME–PLE 0.06. Clypeus height 0.05. Leg measurements: I 2.75 (0.84, 0.90, 0.55, 0.46); II 2.58 (0.78, 0.85, 0.53, 0.42); III 2.54 (0.79, 0.80, 0.54, 0.41); IV 3.16 (0.89, 1.13, 0.75, 0.39). Opisthosoma yellow-brown.
Epigyne (Figs 72G–H, 74C–D). Copulatory openings located posteriorly, separated by the diameter of the opening. Spermathecal heads round. Spermathecal stalks wide. Fertilization ducts long and hooklike.
Distribution. Known only from the type locality, Hainan Island, China.
Funding This work was supported by the National Natural Science Foundation of China (31672278, 31702005), the Key Natural Science Foundation of Chongqing (cstc2019jcyj-zdxmX0006) and the Investigation Project of Basic Science and Technology (2018 FY100305) to Zhisheng Zhang and Luyu Wang.
Acknowledgements The manuscript benefited greatly from comments by two anonymous referees. Sarah Crews checked the English. Theo Blick checked etymology. We thank Feng Zhang and Tianlang Lv for the loan of specimens and Guiqiang Huang for his assistance during field work and collection.