Agelena chayu, Zhang & Zhu & Song, 2005

Zhang, Zhi-Sheng, Zhu, Ming-Sheng & Song, Da-Xiang, 2005, On Agelena labyrinthica (Clerck, 1757) and some allied species, with descriptions of two new species of the genus Agelena from China (Araneae: Agelenidae), Zootaxa 1021 (1), pp. 45-63 : 50-52

Agelena chayu sp. nov. ( Figs. 7–12 )

Type material: Holotype male, Xiachayu (28°30’N, 97°00’E), Chayu, Tibet, China, 8 August 2002, M.S. Zhu et al. leg. ( MHBU) ; Paratypes: 2 males, 23 females, same data as holotype ; 7 males, 8 females, same locality as holotype, 8 July 1980, G. CHEN leg. ( MHBU) .

Etymology: The specific name refers to the type locality, and is a noun in apposition.

Diagnosis: The new species is similar to A. limbata ( Figs. 25–31 ), but can be distinguished from the latter by the small patellar apophysis, the thin embolus, the absence of the conductor median apophysis, the small median apophysis of the male palp; the wide epigynal median septum, the strong spermathecal heads; and the not round spermathecal base of the female.

Description: Male (holotype): Total length 11.93: prosoma 6.22 long, 4.59 wide; opisthosoma 6.22 long, 3.67 wide. Fovea longitudinal. Cervical groove and radial furrow distinct. Both eye rows strongly procurved and the posterior row wider than the anterior one. AME 0.30, ALE 0.28, PME 0.23, PLE 0.30. AME–AME 0.15, AME–ALE 0.10, PME–PME 0.28, PME–PLE 0.23. MOA 0.80 long, front width 0.73, back width 0.70. Clypeus height 0.73. Chelicerae with 3 promarginal and 3 or 4 retromarginal teeth. Distal segment of posterior spinnerets much longer than basal one. Leg formula: 4123.

Measurements of legs:

Femur patella+ tibia metatarsus tarsus total

I 6.73 8.47 7.04 3.16 25.40

II 6.32 7.75 6.43 2.96 23.46

III 5.92 6.73 6.22 2.55 21.42

IV 7.24 8.16 8.57 3.06 27.03

Coloration of male holotype: Prosoma deep yellow, eyes area and its retrolateral areas yellow brown. Chelicerae brown, with orange lateral condyles. Labium and endites yel­ lowish brown. Sternum deep yellow. Legs yellow. Dorsum of the opisthosoma grey, with two longitudinal stripes and four chevron­like markings. Spinnerets yellowish.

Male palp ( Figs. 10–12 ), with a small, blunt patellar apophysis and two tibial ones. Anterior portion of the embolus thin, with an acute tip. Distal portion of conductor with ventral, distal and dorsal apophyses. Median apophysis membranous and small, with a sharp tip.

Female (one paratype): Total length 15.40: prosoma 7.29 long, 5.00 wide; opisthosoma 9.28 long, 6.83 wide. Distal portions of femora and tibia with distinct brown annulate patches. Other characters as in male.

Measurements of legs:

Femur patella+ tibia metatarsus tarsus total

I 6.02 7.34 5.10 2.35 20.81

II 5.71 6.73 4.79 2.35 19.58

III 5.41 5.81 4.69 2.04 17.95

IV 6.63 7.55 6.43 2.45 23.06

Epigyne ( Figs. 8–9 ), with wide median septum of epigynal atrium and two acute processes on the posterior margin near the intersections to lateral margins and copulatory openings situated in the inner part of the processes. Copulatory ducts saccate, anterior parts broad and gradually decreased backwards. Spermathecal heads near midline. Spermathecal stalks short. Spermathecal apophysis originated anteriorly. Fertilization ducts arising from posterior end of spermathecae.

Distribution: China (Tibet).

Figures

FIGURES 7–12. Agelena chayu sp. nov. 7. Male, dorsal view. 8. Female, epigynum, ventral view. 9. Same, vulva, dorsal view. 10. Left palp of the male, prolateral view. 11. Same, ventral view. 12. Same, retrolateral view. Scale bar: 7, 1.0mm; 812, 0.2 mm.

FIGURES 25–30. Agelena limbata Thorell, 1897. 25. Male, dorsal view. 26. Female, epigynum, ventral view. 27. Same, vulva, dorsal view. 28. Left palp of the male, prolateral view. 29. Same, ventral view. 30. Same, retrolateral view. Scale bar: 25, 1.0mm; 26–30, 0.2 mm.

FIGURES 31–39. Agelena silvatica Oliger, 1983. 31. Male, dorsal view. 32–35. Female, epigynum, ventral view. 36. Same, vulva, dorsal view. 37. Left palp of the male, prolateral view. 38. Same, ventral view. 39. Same, retrolateral view. Scale bar: 31, 1.0mm; 32–39, 0.2 mm.