Sesieutes zhui, Zhang, Feng & Fu, Jianying, 2011

Zhang, Feng & Fu, Jianying, 2011, FIRST REPORT OF THE GENUS SESIEUTES SIMON (ARANEAE: LIOCRANIDAE) FROM CHINA, WITH DESCRIPTION OF ONE NEW SPECIES, Entomological News 121 (1), pp. 69-74 : 71-74

Sesieutes zhui , new species, Figs. 1 - 15

Type Data: Holotype male and one female paratype, from Xishuangbanna Dai Autonomous Prefecture (21.08°N, 99.56°E), Yunnan Province, China, 23 October 1986 ( MHBU), collected by M. S. Zhu .

Other type materials: Thailand, Chiang Mai Province, Chomthong District, Doi Inthanon National Park, Doi [Mt.] Inthanon , evergreen hill forest, 1600-1650 m, extraction of soil sample, 1 male and 1 juvenile, 11 January 2006 ; 1 female, pitfall trap, 25 March to 23 April, 2000 [ MHNG] ; 2 males and 2 females, soil sieving, 10 September 2005 [ TNHM] ; 1 female and 3 juveniles, soil sieving, 10 January 2005 [ MHNG] ; 1 male, soil sieving, 9 October 1999 [ MHNG] ; 1 male, evergreen hill forest, 1750 m, soil sieving, 15 January 2000 [ MHNG]. All leg. P. Dankittipakul. Diagnosis: Among its close Sesieutes relatives (see Deeleman-Reinhold 2001) , this species is very similar to S. schwendingeri Deeleman-Reinhold, 2001 (cf. Figs. 771 - 774) in the general body shape, coloration, and shapes of the palpal bulb and epigynum, but distinguished from S. schwendingeri by the anterior copulatory openings ( Fig. 10 ), while situated centrally in S. schwendingeri ; by the length of the copulatory ducts and coiling direction ( Fig. 11 ); also by the distance between the embolus tip and cymbium, nearly touching ( Fig. 14 ), while in S. schwendingeri obviously apart.

Description. Male (holotype) ( Fig. 1 ). Total length 4.88: carapace 2.50 long, 1.95 wide; abdomen 2.38 long, 1.55 wide. Carapace elongate-ovoid, dark reddish brown, with distinct, regular and dense pits. Eye sizes and interdistances ( Fig. 4 ): AME 0.15, ALE 0.15, PME 0.10, PLE 0.13; AME–AME 0.18, AME–ALE 0.13, PME–PME 0.20, PME–PLE 0.20, ALE–PLE 0.20. MOA 0.25 long, front width 0.18, back width 0.23. Clypeus ( Fig. 3 ) height 0.15. Thoracic groove replaced by a deep round pit ( Fig. 1 ). Chelicerae ( Fig. 5 ) usually with three promarginal and two retromarginal teeth. Labium brown ( Fig. 6 ), nearly smooth with few pits, distal with several long bristles, basal with two large pits; endites ( Fig. 6 ) also brown and smooth with few pits, apical inner margin with cluster of fine short hairs. Leg spination: femur I with 2 strong pl spines ( Figs. 8-9 ), other femora spineless; tibia I ( Fig. 7 ) with 7 pv and 8 rv spines, tibia II with 6 pv and 7 rv spines, tibia III with 1 pv, 1 pl and 1 rv spines, tibia IV with 3 pv and 2 rv spines; metatarsus I ( Fig. 6 ) with 5 pairs spines ventrally, metatarsus II with 4 pairs spines ventrally, metatarsus III with 1 pl, 1 pv, and 1 rv spines, metatarsus IV with 3 pv and 2 rv spines. Leg I: 6.81 (1.28+0.85+1.95+1.80+0.93); Leg II: 6.03 (1.68+0.69+1.29+1.45+0.92); Leg III: 3.19 (0.59+0.56+0.69+0.92+0.43); Leg IV: 7.32 (1.52+0.96+1.91+1.95+ 0.98). Leg formula: 4123. Abdomen dark grey dorsally and laterally ( Fig. 1 ), with a pair of small transverse oval white spots and a pair of black muscle impressions centrally, behind these three white chevrons and a white pre-anal spot. Dorsal scutum deep brown, more than 1/3 abdomen length. Ventral side of abdomen light grey, with a pair of parallel white stripes ( Fig. 2 ). Male palp tibia with two apophyses ( Figs. 13-15 ): a blunt distal retrolateral apophysis, and a relatively sharp proximal retrolateral apophysis, with membranous portion surrounding a central groove. Cymbium ( Figs. 12, 14, 15 ) with a dense cluster of fine hairs near apical tip. Tegulum nearly rectangular, inflated, with distinct wide sperm duct centrally ( Fig. 13 ); small subtegulum, prolateral ( Fig. 12 ); embolus filiform, very long, originating from prolateral tegulum, bending dorsally and running alveolus, hidden behind bulb, and tip of embolus aligned with articulating conductor ( Figs. 12-15 ). Conductor apical, somewhat helix-shaped, with a central groove to accommodate the embolus.

Female (paratype). Total length 6.13: cephalothorax 3.23 long, 2.26 wide; abdomen 2.90 long, 1.64 wide. Eye sizes and interdistances: AME 0.16, ALE 0.16, PME 0.11, PLE 0.13; AME–AME 0.19, AME–ALE 0.16, PME–PME 0.23, PME–PLE 0.26, ALE–PLE 0.25. MOA 0.23 long, front width 0.26 back width 0.32. Clypeus height 0.16. Eyes, endites, labium, sternum, and legs almost as in male. Carapace like male but with small granules along border. Abdomen without dorsal scutum, pattern as in male. Spination similar to male. Leg I: 8.33 (0.97+2.10+2.23+0.71+ 2.32); Leg II: 6.12 (1.02+1.61+1.87+0.68+1.94); Leg III: 5.59 (0.88+1.351.10+ 0.65+1.61); Leg IV: 8.92 (1.07+2.23+2.32+0.94+2.36). Leg formula: 4123. Epigynum as illustrated ( Figs. 10-11 ), flat plate, a little wider than long; with paired copulatory openings anteriorly, leading through long and winding sclerotized ducts into posterior spermathecae. Spermathecae nearly globose.

Etymology. The specific name is a patronym in honor of Prof. Mingsheng Zhu, who collected the holotype and one paratype specimens.

Distribution. China, Thailand.

Natural History. Typically a ground-dwelling liocranid sac spider, these specimens were collected from the sunlit monsoon forest by sifting leaf litter in tropical China. The specimens of Thailand were collected from evergreen hill forest in various times of year by several methods, for example, extraction of soil sample, pitfall trap and soil sieving.

Figures

Figures 1 - 9. Sesieutes zhui sp. nov 1. Male body, dorsal view. 2. Male abdomen, ventral view. 3. Carapace and chelicerae of male, front view, showing clypeal lobe and lateral condyle. 4. Eye region of male, dorsal view. 5. Left chelicerae of male, posterior view. 6. Endites, labium and sternum of male, ventral view, showing granulations. 7. Tibia, metatarsus and tarsus of male right leg I, showing spines. 8. Male femur I, dorsoprolateral view, showing two strong spines. 9. Male femur I, showing larger spines. CL = clypeal lobe; DS = dosal scutum; ES = epigastric scutum; LC = lateral condyle; MI = muscle impression; P = pits; PS = prolateral spine; TG = thoracic groove. Scale bars: 1 – 3, 6 – 8, 1 mm; 4 and 9, 0.5 mm; 5, 0.7 mm.

Figures 10 - 15. Sesieutes zhui sp. nov. 10. Epigynum, ventral view. 11. Vulva, dorsal view. 12. Left male palp, prolateral view. 13. Left male palp, ventral view. 14. Left male palp, retrolateral view. 15. Left palp, dorsal view, showing tibial apophyses and fine hairs of cymbium. C = conductor; CH = cymbium hairs; CD = copulatory duct; CO = copulatory opening; E = embolus; FD = fertilization duct; T = tegulum; SD = sperm duct; ST = subtegulum; dRTA = distal retrolateral tibial apophysis; pRTA = proximal retrolateral tibial apophysis; S = spermathecae. Scale bars: 10 - 15, 0.5 mm.