Trachelas alticolus Hu, 2001

Zhang, Feng, Fu, Jian-Ying & Zhu, Ming-Sheng, 2009, A review of the genus Trachelas (Araneae: Corinnidae) from China, Zootaxa 2235, pp. 40-58 : 45-48

Trachelas alticolus Hu, 2001

( Figs. 11–16 )

Trachelas alticolus Hu, 2001: 302 , f. 8–177.

Geodrassus digitusiformis Hu, 2001: 244 , f. 8–136 (only female holotype; male allotype not conspecific, Drassodes sp.). New synonymy.

Drassodes digitusiformis: Platnick, 2009 .

Diagnosis. This species resembles Trachelas japonicus and T. sinensis , all with male palpal femur concave on the distal part ventrally, and epigynum with globose spermathecae and oval bursa; but can be distinguished from the latter species by: (1) carapace without granulations; (2) the thinner and longer embolus; (3) beakshaped patellar apophysis and thumb-shaped tibial apophysis; (4) spermathecae composed of two globose parts; (5) the patterns of abdomen dorsally. Distinguished from T. japonicus also by the arch-shaped epigynal hood, and from T. sinensis also by the transverse bursa.

Redescription. Male. Total body length 4.56–5.44. A male was measured (Yadong County), total length 5.23: cephalothorax 2.28 long, 2.03 wide; abdomen 2.95 long, 1.48 wide. Carapace ( Fig. 11 ) red brown, ovoid in dorsal view, somewhat truncated at posterior margin, highest between fovea and PER; sparsely covered with short pale erect setae, but without granulations. Fovea long and indistinct. Cephalic groove and radial furrow brown. Clypeal height 0.12. Eye diameter: AME 0.10, ALE 0.10, PME 0.11, PLE 0.11; eye interdistance: AME–AME 0.08, AME–ALE 0.05, PME–PME 0.10, PME–PLE 0.07; MOA 0.17 long, anterior width 0.13, posterior width 0.25. Chelicerae dark orange, stout and hairy; promargin with three and retromargin with two teeth. Endites longer than wide, convex on lateral margin. Labium brown. Sternum shield-shaped, light brown. Legs brown, without spines and cusps. Leg formula 1423 ( Table 3).

Femur Patella Tibia Metatarsus Tarsus Total I 2.23 0.90 1.89 2.07 0.98 8.07 II 2.08 0.75 1.65 1.58 0.90 6.96 III 1.38 0.52 1.09 1.23 0.72 4.94 IV 1.90 0.75 1.58 1.97 0.83 7.03 Abdomen ( Fig. 11 ) longitudinal ovoid, yellow brown; dorsum with two pairs of sigilla in the middle part, and several pairs of gray markings. Venter of abdomen light brown.

Male palp as illustrated ( Figs 12–14 ). Femur largely concave on the distal part ventrally, and with a row of small cuticular denticles ventrally ( Figs 13–14 ); patella with a beak-shaped apophysis from retrolateral view; tibia with a thumb-shaped proximal apophysis dorsally, pointed out and down. Cymbium round at base, long and slender, bent ventrally on distal part and without cymbial furrow; tegulum ( Fig. 12 ) expanded roundedly at base, long twisted loop of sperm duct distinct from embolus to central part of tegulum. Embolus long and arising prolaterally and distally, composed of membranous and sclerotised parts; its tip tapered and curved retrolaterally, and partly concealed by the cymbium from ventral view ( Fig. 12 ). Subtegulum with an expanded part, thin, thumb-shaped from prolateral view ( Fig. 13 ).

Female. Carapace colour, eye arrangement, abdominal colouration as for male. Total body length 4.94– 5.88. A female was measured (Yadong County), total length 5.37; cephalothorax 2.25 long, 1.93 wide; abdomen 3.12 long, 1.82 wide. Eye diameters: AME 0.10, ALE 0.10, PME 0.11, PLE 0.11; eye interdistances: AME–AME 0.06, AME–ALE 0.08, PME–PME 0.11, PME–PLE 0.13; MOA 0.30 long, anterior width 0.34, posterior width 0.28. Legs brown, without spines and cusps.. Leg formula: 1423 ( Table 4).

Epigynum as illustrated ( Figs 15–16 ). Copulatory openings concave, short, expanded to oval atrium on the anterior part. Bursa situated on the outer part of copulatory opening anteriorly, nearly oval; spermathecae composed of two parts, both globose, situated in the posterior part of epigynum, connected to each other with a short duct and then, through thinner and longer ducts connected to the copulatory ducts; fertilization ducts short, arising from the posterolateral ends of the spermathecae.

Femur Patella Tibia Metatarsus Tarsus Total I 2.35 0.75 1.50 1.58 0.80 6.98 II 1.70 0.68 1.47 1.49 0.75 6.09 III 1.20 0.46 0.98 1.23 0.65 4.52 IV 2.05 0.65 1.27 1.46 0.70 6.13 Distribution. China: Xizang.

Type material. Trachelas alticolus Hu, 2001 , holotype male, from Rigaze Prefecture, Tibet; paratype 1 male from Zham Town, Nyalam County, Tibet, in Shandong University, China, not examined. Geodrassus digitusiformis Hu, 2001 , female holotype from Gyirong County, and male allotype (misidentified, Drassodes sp.) from Nyingchi County, paratypes 4 females from Yadong County and Gyirong County, paratypes 2 females and 1 male from Kongpo Gyamda County, all in Shandong University, China, not examined.

Material examined. CHINA: Xizang, Nyingchi County, 13, 19 July 1988, F. P. Zhang leg. ( MHBU); 1Ƥ, 23, 17 August 2002, M. S. Zhu and J. X. Zhang leg. ( MHBU); Mainling County, 163, 19 August 2002, F. Zhang and J. X. Zhang leg. ( MHBU); Nang County, 13, 20 August 2002, J. X. Zhang leg. ( MHBU);Lhodak County [N 25.34°, E 100.13°], 13, 22 August 2002, F. Zhang and Z. S. Zhang leg. ( MHBU); Lhasa City [N 25.34°, E 100.13°] 1Ƥ, 23, 30 August 2002, M. S. Zhu and F. Zhang leg. ( MHBU); Gyirong County [N 25.34°, E 100.13°], 1Ƥ, 33 31 August 2002, M. S. Zhu and J. X. Zhang leg. ( MHBU);Nyalam County [N 25.34°, E 100.13°], 13, 31 August 2002, F. Zhang and Z. S. Zhang leg. ( MHBU); Nedong County [N 25.34°, E 100.13°], 9Ƥ, 13, 25 August 2002, M. S. Zhu and F. Zhang leg. ( MHBU); Yadong County [N 25.34°, E 100.13°], 6Ƥ, 83, 4 September 2002, F. Zhang and Z. S. Zhang leg. ( MHBU).

Remarks. Hu (2001) described T. alticolus from the male only. In the same book he also described Geodrassus digitusiformis (= Drassodes digitusiformis , Gnaphosidae ) from both sexes, and from the figures the female holotype is certainly a species of Trachelas , but its male allotype did not match with the female, and is probably a species of the genus Drassodes . For various reasons we could not examine the type specimens of T. alticolus and D. digitusiformis from Shandong University, so we must judge from the figures only. Additionally, during 2004 we collected many Trachelas specimens from Xizang Autonomous Region, among them males and females of T. alticolus , collected together in the same location. We also matched them together on the basis of somatic and genitalic characters.

Figures

FIGURES 11 – 16. Trachelas alticolus Hu, 2001. 11. Male body, dorsal view. 12. Left male palp, ventral view. 13. Same, prolateral view. 14. Same, retrolateral view. 15. Epigynum, ventral view. 16. Vulva, dorsal view. Scale bars: 1 mm (11); 0.3 mm (15 – 16); 0.4 mm (12 – 14).