Arctosa truncata, Tso & Chen, 2004

Tso, I-Min & Chen, Jun, 2004, Descriptions Of Three New And Six New Record Wolf Spider Species From Taiwan (Arachnida: Araneae: Lycosidae), Raffles Bulletin of Zoology 52 (2), pp. 399-411 : 402-403

Arctosa truncata , new species

( Figs. 11-16 )

Material examined. – Holotype - female, Lugu Country , Nantou County, Taiwan, 26 Aug.1995, coll. Wen-Hao Chou (NMNS-THU- Ar-02-0158).

Paratype – 1 male, Lugu Country , Nantou County, Taiwan, 24 Aug.1995, coll. Wen-Hao Chou (NMNS-THU-Ar-02-0156) .

Diagnosis. – Total length 4.66-5.88; carapace with distinct pattern; epigynal plate of female with a pair of slightly concaved lateral hollows; pedipalp with several thick setae clustering together, median apophysis triangle shaped, directed laterally, distal part twisted in 90 and curved ventrally, distal margin truncated, embolus slightly twisted, distal part thin and long, terminal apophysis slightly curved.

Etymology. – The specific name refers to the truncated distal part of the median apophysis.

Description. – Female: Holotype: Total length 5.88, carapace length 3.13, width 2.27; abdomen length 2.88, width 1.96. Body brown. Head sloped laterally. Carapace with distinct

pattern ( Fig. 11 ), median band extending anteriorly between PLEs; lateral bands broken; sublateral bands narrow; margins of carapace dark brown. Anterior eye row almost straight, AME slightly larger than ALE, AME-AME longer than AME-ALE. Clypeus about 0.9 times the diameter of AME. Chelicerae with 3 promarginal teeth and 3 retromarginal teeth. Sternum yellowish-brown, with brown spots along margins. Legs and pedipalp with distinct annulations. Leg measurements: I 7.35 (2.15, 0.98, 1.65, 1.59, 0.98); II 6.86 (1.96, 0.98, 1.41, 1.53, 0.98); III 6.62 (1.90, 0.92, 1.23, 1.65, 0.92); IV 9.93 (2.70, 1.23, 2.02, 2.76, 1.22). Dorsum of abdomen scattered with whitish pubescence, and with pale spots along and behind heart stripe; middle part of venter brown, lateral yellowish. Epigynal plate with a pair of slightly concaved lateral hollows ( Fig. 12 ), copulatory openings not distinct, copulatory tube short, spermathecae expanded, round ( Fig. 13 ).

Male: Total length 4.66, carapace length 2.70, width 2.02; abdomen length 2.08, width 1.47. Similar to female in general shape and colour. Body slightly darker than female. Clypeus about 0.6 times the diameter of AME. Legs measurements: I 7.04 (1.96, 0.92, 1.59, 1.53, 1.04); II 6.44 (1.72, 0.86, 1.35, 1.47, 1.04); III 5.93 (1.65, 0.67, 1.16, 1.59, 0.86); IV 9.20 (2.33, 0.98, 1.96, 2.70, 1.23). Pedipalp with several thick setae clustering together. Median apophysis triangular, directed laterally, distal part twisted in 90 and curved ventrally, distal margin truncated ( Figs. 14-15 ); embolus narrow, slightly twisted; terminal apophysis slightly curved ( Fig. 16 ).

Remarks. – This species is very close to Arctosa xunyangensis Wang & Qiu, 1992 . It can be distinguished from the latter by following: in A. truncata , body smaller (female length 5.88, male length 4.66), copulatory opening not distinct, distal part of median apophysis truncated; in A. xunyangensis , body larger (female length 7.50-8.20, male length 5.20-5.70), copulatory opening distinct, distal part of median apophysis pointed and long.

Distribution. – Taiwan.

Figures

Figs. 11-16. Arcotosa truncata, new species. 11. carapace (female, dorsal view); 12-13. epigynum (12. ventral view; 13. dorsal view); 14- 15. left pedipalp of male (14. ventral view; 15. retrolateral view); 16. terminal part of right pedipalp (ventral view). Scale bars: Fig. 11 = 0.80mm; Figs. 12-15 = 0.15mm; Fig. 16 = 0.10mm.