Pterotricha arabica, Zamani, Alireza, 2018

Zamani, Alireza, 2018, The spider genus Pterotricha Kulczynski, 1903 (Araneae, Gnaphosidae) in the United Arab Emirates, Evolutionary Systematics 2 (2), pp. 151-161 : 151

Pterotricha arabica sp. n. Figs 1 a–b, 2a, 3a, 4 a–d, 5a, 6

Holotype.

♂ (AMNH_IZC 00326723), UAE: Umm Al Zumul, 22°52'N, 55°10'E, 2 Feb 1995, mobile sand.

Paratypes.

1♀, (AMNH_IZC 00326766), Madinat Zayed, 23°50'N, 54°6'E, 1 Jan 1995, mobile sand; 1♂ (AMNH_IZC 00326772), Madinat Zayed, 23°51'N, 54°5'E, 10 Feb 1994, mobile sand; 1♀, 1 sub ♀ (AMNH_IZC 00326717), Madinat Zayed, 23°51'N, 54°3'E, 5 Oct 1994, gravel/hard plain; 1♀, 1 sub ♀, 1 juv. (AMNH_IZC 00326704), Khatam, 23°52'N, 55°23'E, 9 Oct 1994, mobile sand; 1♀, 1 juv. (AMNH_IZC 00326744), Madinat Zayed, 23°51'N, 54°4'E, 10 May 1994, mobile sand; 1♀ (AMNH_IZC 00326705), Madinat Zayed, 23°51'N, 54°4'E, 3 Dec 1994, mobile sand; 4♂, 1 juv. (AMNH_IZC 00326775), Madinat Zayed, 23°51'N, 54°4'E, 11 Apr 1994, mobile sand; 1♀, 1 juv. (AMNH_IZC 00326726), Madinat Zayed, 23°51'N, 54°4'E, 5 Oct 1994, mobile sand; 1♂, 3 juv. (AMNH_IZC 00326703), Umm Al Zumul, 22°54'N, 55°11'E, 15 March 1994; UAE: 1♂, 1 juv. (AMNH_IZC 00326733), Umm Al Zumul, 22°52'N, 55°10'E, 14 Apr 1994; 1♀ (AMNH_IZC 00326721), Madinat Zayed, 23°51'N, 54°5'E, 3 Nov 1994, mobile sand; 1♂ (AMNH_IZC 00326727), Madinat Zayed, 23°51'N, 54°5'E, 12 March 1994; 1♂ (AMNH_IZC 00326727), Madinat Zayed, 23°51'N, 54°5'E, 12 March 1994; 1♂ (AMNH_IZC 00326750), Madinat Zayed, 23°51'N, 54°5'E, 7 Aug 1994, mobile sand; 2♂ (AMNH_IZC 00326756), Umm Al Zumul, 22°52'N, 55°10'E, 2 Feb 1995, mobile sand; 1♂ (AMNH_IZC 00326762), Khatam, 23°53'N, 55°22'E, 3 Feb 1995, mobile sand; 1♂ (AMNH_IZC 00326769), Umm Al Zumul, 22°52'N, 55°10'E, 15 Jan 1994, mobile sand; 2♂ (AMNH_IZC 00326715), Khatam, 23°52'N, 55°23'E, 15 Apr 1994; 1♂, 1 juv. (AMNH_IZC 00326843), Khatam, 23°53'N, 55°22'E, 14 Feb 1994; 1♀ (AMNH_IZC 00326836), Umm Al Zumul, 22°53'N, 55°10'E, 15 March 1994; 2♂ (AMNH_IZC 00326794), Umm Al Zumul, 22°52'N, 55°10'E, 13 Feb 1994; 1♀ (AMNH_IZC 00326836), Umm Al Zumul, 22°53'N, 55°10'E, 15 March 1994; 1♀, 1 juv. (AMNH_IZC 00326785), Umm Al Zumul, Madinat Zayed, 23°51'N, 54°4'E, 9 June 1994, mobile sand; 2♂ (AMNH_IZC 00326761), Public Hunting Triangle, 24°39'N, 55°10'E, 12 Apr 1994; 1♀ (AMNH_IZC 00326780), Umm Al Zumul, 22°53'N, 55°2'E, 15 Jan 1994, mobile sand; 1♂ (AMNH_IZC 00326816), Public Hunting Triangle, 24°39'N, 55°8'E, 12 Apr 1994; 1 sub ♂, 1♀, 3 juv. (AMNH_IZC 00326828), Khatam, 23°52'N, 55°21'E, 20 Oct 1993; 1♂ (AMNH_IZC 00326814), Madinat Zayed, 23°51'N, 54°4'E, 9 June 1994; 1♂, 1♀ (AMNH_IZC 00326790), Khatam, 23°53'N, 55°22'E, 3 Feb 1995, mobile sand; 1♂, 1♀ (AMNH_IZC 00326840), Umm Al Zumul, 22°54'N, 55°10'E, 4 Jan 1995, mobile sand; 1♂ (AMNH_IZC 00326849), Khatam, 23°52'N, 55°22'E, 14 Feb 1994; 1♂ (AMNH_IZC 00326841), Madinat Zayed, 23°51'N, 54°4'E, 10 May 1994.

Etymology.

The specific epithet refers to the Arabian Peninsula, from where the specimens have been collected.

Diagnosis.

This species is most similar to P. syriaca Dalmas, 1921 from Syria by the almost horizontal tibial apophysis tapering to a bifurcated tip of the males (cf. Figs 2a, 3a and fig. 118 in Levy 1995), and by the similarly rounded epigynal plates of the females (cf. Fig. 4c, d and fig. 119 in Levy 1995). The two species can be separated by the different shape of the median apophysis of the male palp (almost rounded in P. syriaca (cf. fig. 35 in Dalmas 1921), vs. with a distinct prolateral protrusion in the new species (cf. Figs 2a, 4a, b)) and by the different shape of the epigynal anterior depression of the females (with a median depression in P. syriaca (cf. fig. 119 in Levy 1995), vs. with a rounded rim, lacking any depression in the new species (cf. Fig. 4c, d)).

Description.

Male (holotype, AMNH_IZC 00326723). Total length 11.5. Carapace 4.8 long, 4.3 wide. Eyes sizes and interdistance: AME: 0.22, ALE: 0.20, PME: 0.22, PLE: 0.30, PME–PME: 0.15. Carapace, sternum, labium, chelicerae and maxillae light brown without any distinct patterns, with darkening ocular area. Chelicerae with bifurcated serrated keels (Fig. 5a). Abdomen cream with short transparent setae and a small scutum. Legs the same color as carapace and with numerous spines. Scopula on metatarsi and tarsi distinct and with long setae. Tarsi of all legs with cuticular cracks (pseudosegmentations). Measurements of legs: I: 23.3 (5.95, 2.25, 5.65, 5.2, 4.25), II: 26.8 (6.4, 2.3, 6.3, 7.9, 3.9), III: 22.1 (5.6, 2.1, 5.2, 5.4, 3.8), IV: 30.6 (8.4, 2.2, 7.1, 8.7, 4.2). Anterior lateral spinnerets 4.9 long, 0.42 wide. Palp as in Figs 2a, 3a, 4 a–b. Tibial apophysis almost horizontal, tapering to a bifurcated tip; median apophysis longer than wide with large base having a distinct prolateral protrusion, and an almost straight apical hook; conductor large, tip with a small invagination; embolus filliform and without a stylus, origination near the 6:30 o’clock position and tapering near the apex of conductor.

Female (paratype, AMNH_IZC 00326717). Total length 13.0. Carapace 4.85 long, 4.35 wide. Eyes sizes and interdistance: AME: 0.25, ALE: 0.22, PME: 0.3, PLE: 0.35, PME–PME: 0.12. Coloration and somatic characters as in male. Measurements of legs: I: 15.9 (4.7, 1.9, 3.1, 3.0, 3.2), II: 15.9 (4.3, 1.9, 3.3, 3.3, 3.1), III: 18.5 (5.0, 2.0, 4.2, 4.3, 3.0), IV: 21.9 (6.0, 2.0, 5.2, 5.2, 3.5). Anterior lateral spinnerets 3.65 long, 0.45 wide. Epigyne as in Fig. 4 c–d. Median septum broad, with a rounded rim of anterior margin, and with widening posterior end. Copulatory duct long and looped, leading to a large, longer than wide receptacle (Re).

Ecology.

This nocturnal species builds tubular retreats on firm sandy flats, generally on the edge of the gravel plains towards the vegetation and in dunes. They have been observed to seal the entrance of their burrow in the early morning and open them again in the sunset, and to use silk-covered sand balls around the entrance in a fan-shaped manner, with radiating silk strands leading back to the burrow ( Roosenschoon and Simkins 2015). Open burrows have been reported to be vertical, silk-lined and surrounded at a short distance by a crater of soft sand ( Feulner and Roobas 2015).

Distribution.

Currently known from the listed localities in the United Arab Emirates (Fig. 7), and, based on some photographs provided for me, also present in Dubai Desert Conservation Reserve, about 75 km SE of Dubai city, on the border of Dubai emirate with Sharjah and Abu Dhabi.