Pterotricha esyunini sp. n. Figs 1c, 2b, 3b, 5 b–c

Holotype.

♂ (AMNH_IZC 00326774), UAE: Baynunah, 27 Feb 1995.

Paratypes.

1♂ (AMNH_IZC 00326753), Madinat Zayed, 23°50'N, 54°6'E, 10 Feb 1994; 1♂ (AMNH_IZC 00326834), Madinat Zayed, 23°50'N, 54°6'E, 11 Apr 1994; 1♂ (AMNH_IZC 00326809), Public Hunting Triangle, 24°40'N, 55°3'E, 28 Jan 1994.

Etymology.

This species is named after the Russian arachnologist Sergei L. Esyunin, in recognition of his contributions to the taxonomy of gnaphosid spiders.

Diagnosis.

This species is easily diagnosed from other congeners by the presence of a dorsal horizontal extension at the base of the tibial apophysis (Fig. 3b).

Description.

Male (holotype, AMNH_IZC 00326774). Total length 8.3. Carapace 3.9 long, 3.4 wide. Eyes sizes and interdistance: AME: 0.20, ALE: 0.22, PME: 0.22, PLE: 0.20, PME–PME: 0.12. Carapace, sternum, labium, chelicerae and maxillae light brown without any distinct patterns, with darkening ocular area. Chelicerae with a triangular serrated keel retrolaterally (Fig. 5b), and a bifurcated serrated keel prolaterally (Fig. 5c). Abdomen cream-coloured with short scattered setae and with a scutum anteriorly. Legs the same color as carapace and with spines. Tarsi of all legs with pseudosegmentations. Scopula on metatarsi and tarsi indistinct. Measurements of legs: I: 15.8 (4.45, 1.70, 3.35, 3.95, 2.35), II: 17.7 (4.45, 1.95, 3.3, 5.0, 3.0), III: 16.45 (4.25, 1.9, 3.30, 4.35, 2.65), IV: 20.15 (5.25, 1.95, 4.00, 5.95, 3.0). Anterior lateral spinnerets 1.5 long, 0.30 wide. Palp as in Figs 2b, 3b. Tibia with a long, strong macroseta (Ms) on the dorsal side; Tibial apophysis L-shaped with bifurcated tip, with a large dorsal horizontal extension (Ls) at the base; median apophysis with large elliptic base and a curved apical hook; conductor large; embolus simple and without a stylus, tapering near the apex of conductor terminating in a whip-like manner.

Female. Unknown.

Distribution.

Currently known only from the listed localities in the United Arab Emirates (Fig. 7).