Pistius rotundus, Tang & Li, 2010

Tang, Guo & Li, Shuqiang, 2010, Crab spiders from Xishuangbanna, Yunnan Province, China (Araneae, Thomisidae) 2703, Zootaxa 2703, pp. 1-105 : 54-56

Pistius rotundus sp. nov.

Figs 39–41

Type material. Holotype: ♂, CHINA: Yunnan: Xishuangbanna, Mengla County, Menglun Town , Menglun Nature Reserve , secondary tropical seasonal moist forest (N21º54.607', E101º17.005', 633 m), 28 July 2007, leg. G. Zheng (Zheng_sp916).

Paratypes: CHINA: Yunnan: Xishuangbanna, Mengla County, Menglun Town , Menglun Nature Reserve , leg. G. Zheng: 12 ♂, 4 ♀, same data as holotype ; 6 ♂, 1 juvenile ♀, secondary tropical seasonal moist forest (N21º54.718', E101º16.940', 645 m), 27 July 2007 ( Zheng _sp1121) ; 1 ♂, 1 juvenile ♂, secondary tropical seasonal moist forest (N21º54.948', E101º16.982', 656 m), 10 August 2007 ( Zheng _sp228) ; leg. G. Tang and Z.Y. Yao: 2 ♀, Lvshilin Forest Park, Limestone tropical seasonal rain forest (N21º54.705', E101º16.898', 656 m), 13 November 2009 ( Tang-Yao _ No. 4) ; 1 ♀, Lvshilin Forest Park, Limestone tropical seasonal rain forest (N21º54.710', E101º16.941', 652 m), 15 November 2009 ( Tang-Yao _ No. 9) ; 1 ♀, Lvshilin Forest Park, Limestone tropical seasonal rain forest (N21º54.609´, E101º17.090´, 643 m), 17 November 2009 ( Tang-Yao _ No. 13) .

Etymology. The specific name comes from the Latin word rotundus (round), referring to the embolus twisted round in retrolateral view, adjective.

Diagnosis. This new species can be easily distinguished from P. truncatus (Pallas, 1772) and P. undulatus Karsch, 1879 by the slender, twisted embolus.

Description. Male (holotype measured): Total length 4.00. Prosoma 1.80 long, 1.80 wide; opisthosoma 2.25 long, 2.10 wide. Prosoma flat, dorsally greenish brown. Eye tubercles grayish white. Eye measurements: AME 0.07; ALE 0.11; PME 0.06; PLE 0.10; AME–AME 0.18; AME–ALE 0.12; PME–PME 0.18; PME–PLE 0.26. MOA length 0.28 with front width 0.32 and back width 0.31. Chelicerae brown, gnathocoxae, labium yellow, sternum yellow with grayish black rim. Legs yellow. Leg measurements: I: 8.30 (2.40, 3.10, 1.90, 0.90); II: 8.20 (2.40, 3.00, 1.90, 0.90); III: 3.00 (1.00, 1.10, 0.50, 0.40); IV: 3.10 (1.00, 1.20, 0.50, 0.40), leg formula: 1243. Opisthosoma widest at the 2/3 position. opisthosoma dorsally yellow with grayish black markings, dorsally also with some small brown spots which each mounted with a short seta. The lateral with grayish black lines, venter yellow.

Palp ( Figs 39 B–D, 41 A–B). VTA digitiform, combined with ITA basally; ITA with a small, sharp membranous ramus; RTA bifurcated, the dorsal ramus sclerotized, pointed distally; cymbium dorsally with a brush of scopulae in anterior part ( Fig. 39B), tegulum with a tongue-shaped apophysis, embolus slender and twisted around tegulum and in a free distal loop.

Female (one of the paratypes measured): Total length 5.30. Prosoma 2.20 long, 2.50 wide. Opisthosoma 2.50 long, 3.20 wide. Body lighter than in male. Eye measurements: AME 0.07; ALE 0.12; PME 0.06; PLE 0.11; AME– AME 0.24; AME–ALE 0.16; PME–PME 0.24; PME–PLE 0.36. MOA length 0.32 with front width 0.38 and back width 0.36. Leg measurements: I: 8.70 (2.80, 3.30, 1.80, 0.80); II: 8.60 (2.80, 3.20, 1.80, 0.80); III: 3.70 (1.10, 1.50, 0.60, 0.50); IV: 3.60 (1.10, 1.40, 0.60, 0.50), leg formula: 1234. Opisthosoma dorsally grayish white with black markings, dorsally also with small brown spots and setae.

Epigynum ( Figs 40 B–C, 41 C–D). Epigynum with a small anteriorly situated hood covered by a transparent sclerotized plate, copulatory openings bilaterally, copulatory duct soft tube-shaped, long, twisted; spermathecae short.

Variation. Total length: ♂ 3.30–4.30 (n=11); ♀ 4.80–5.60 (n=16).

Distribution. China (Yunnan).

Remarks. The genera Massuria Thorell 1887 and Pistius Simon, 1875 have been systematically confused by most Indian authors, and most or all species of the genus Pistius described from India were probably misplaced and belong to Massuria Thorell, 1887 ( Lehtinen, 2005) .