Type material. Holotype: ♂ ( IZCAS-Ar39717), CHINA: Hainan: Sanya City, Jiyang District, Dadonghai, N18.2180°, E109.5151°, elev. - 3 m, 22.IV.2018, Yejie Lin & Jiaxiang Wu leg. Paratypes: 1♀ ( IZCAS-Ar39718) and 1♂, 1♀ ( SMF), with same data as holotype.
Etymology. The species is named after Mr Jiaxiang Wu, the collector of the holotype; noun (name) in genitive case.
Diagnosis. Males of Desis jiaxiangi sp. nov. are similar to those of D. bobmarleyi and D. japonica in having a similarly shaped C and a DTA with hood, but can be distinguished by the leaf-shaped tip of MTA (spine-like in D. bobmarleyi and D. japonica) and the internal angle between the dRTA and vRTA wide (smaller in D. bobmarleyi). Females similar to those of D. gardineri, D. bobmarleyi and D. japonica in having globular SP, long convoluted CD arranged circularly and a tongue-shaped, apically obtuse AS, but can be distinguished by having CO situated between convoluted CD and SP in ventral view (on the level of posterior half of SP in D. japonica), chelicerae with six promarginal teeth and AS arising from half way between CO and posterior epigynal margin (three promarginal teeth and AS arising from posterior epigynal margin in D. gardineri), and spermathecal head pointing anteriorly (spermathecal head pointing posteriorly in D. bobmarleyi).
Description. Male ( holotype, IZCAS-Ar39717). Total length 8.20, carapace 4.30 long, 2.81 wide, red brown, posterior lighter. Opisthosoma 4.30 long, 2.20 wide. Anterior eye row slightly recurved, posterior eye row straight. Eye sizes and interdistances: AME 0.10, ALE 0.16, PME 0.12, PLE 0.14, AME–AME 0.10, AME–ALE 0.20, PME–PME 0.29, PME–PLE 0.24, AME–PME 0.15, ALE–PLE 0.13. Clypeus height 0.08. Chelicerae large, red brown with six promarginal and two retromarginal teeth. Paturon 3.84 long. Endites, labium and sternum red brown. Legs grey covered with a great number of grey setae. Leg measurements: leg I: 14.89 (3.20 + 5.26 + 4.20 + 2.23), leg II: 10.46 (2.63 + 3.44 + 2.84 + 1.55), leg III: 8.96 (2.55 + 2.69 + 2.48 + 1.24), leg IV: 12.61 (3.44 + 4.35 + 3.32 + 1.5). Leg formula: 1423. Opisthosoma grey, covered with a dense layer of grey setae.
Male palp ( Figs 1–2) as in diagnosis. RTA longer than wide, slightly C-shaped. C large, running around oval tegulum, its apex situated in a 1.30-o’clock-position, with broadly triangular CP. MTA originating medially from apex of CP, thin, translucent, tip apically expanded and leaf-shaped. DTA with hood. E thin, arising from tegulum in 9-o’clock-position, running 1.25 windings around the tegulum, embedded in C.
Female (IZCAS-Ar39718, paratype). Total length 11.15, carapace 4.40 long, 2.81 wide, opisthosoma 6.15 long, 3.56 wide. Colour as in male. Eye sizes and interdistances: AME 0.16, ALE 0.16, PME 0.15, PLE 0.15, AME–AME 0.13, AME–ALE 0.20, PME–PME 0.30, PME–PLE 0.29, AME–PME 0.13, ALE–PLE 0.11. Clypeus height 0.06. Chelicerae with four promarginal and three retromarginal teeth. Leg measurements: Leg I: 13.94 (3.24 + 5.06 + 3.88 + 1.76), leg II: 10.71 (2.66 + 3.72 + 2.88 + 1.45), leg III: 8.33 (2.28 + 2.44 + 2.47 + 1.14), leg IV: 11.92 (3.00 + 4.45 + 2.97 + 1.50). Leg formula: 1423.
Epigyne and vulva ( Figs 3 A–B) as in diagnosis. CO covered anteriorly by M-shaped rim. ET broad, about three times longer than wide. AS tongue-shaped, posterior end obtuse. CD long, convoluted, arranged circularly. SH distinct. SP globular, separated from each other by about a third of their diameter.
Distribution. Known only from the type locality.
Life history. Individuals of the new species were collected from reef intertidal zones and show up during low tide to hunt small marine aquatic animals and flies. Their habitat is completely flooded during high tide.