Cheiracanthium auriculatum, Zhang, Jianshuang, Zhang, Guren & Yu, Hao, 2018

Zhang, Jianshuang, Zhang, Guren & Yu, Hao, 2018, Four species of spider genus Cheiracanthium C. L. Koch, 1839 (Araneae, Eutichuridae) from Jinggang Mountains, Jiangxi Province, China, ZooKeys 762, pp. 33-45 : 33

Cheiracanthium auriculatum sp. n. Figs 1, 5

Type material.

Holotype ♂ (SYSU-JX-11-177): China, Jiangxi Province, Jinggang Mountains Nature Reserve, Xiangzhou village (380 m; 26°35'30.23"N, 114°15'59.93"E), 26 April 2011, Hao Yu and Zhenyu Jin leg. Paratypes: 1♂ and 3 ♀, same data as holotype.

Etymology.

The specific epithet is an adjective and is derived from a Latin word “auriculatus“ (ear-like), referring to the tegular apophysis which is like the contour of an ear in ventral view.

Diagnosis.

Cheiracanthium auriculatum sp. n. is distinguished from all other Cheiracanthium species, except C. zhejiangense Hu & Song, 1982 (Fig. 4 A–E), by having a distally filiform cymbial spur in the male, and by the general shape of the vulva in the female. From C. zhejiangense , the male can be distinguished by the ear contour-shaped tegular apophysis and the uncoiling tip of cymbial spur (vs the falciform tegular apophysis and the coiled tip of the cymbial spur in C. zhejiangense ) (Figs 1 A–C; 4 A–C), the female can be differentiated by the indistinct atrium and copulatory ducts (vs the distinct atrium and copulatory ducts in C. zhejiangense ), the more or less lengthwise receptacles (vs the nearly horizontal receptacles in C. zhejiangense ) (Figs 1 D–E; 4 D–E), and by the different coil number of copulatory ducts (7 coils in C. auriculatum sp. n., instead of 8 coils in C. zhejiangense ) (Figs 1E; 4E). In addition, the two species can by separated by their habitus: abdomen without distinct colour pattern in C. auriculatum sp. n. (Fig. 1 F–G), but with a median heart-shaped mark which reaches half of the opisthosoma length in C. zhejiangense (Fig. 4 F–G).

Description.

Male. Total length 8.58-9.15. Holotype (Fig. 1 A–C, F): TL 9.15; CL 3.73, CW 2.41, CI (CL/CW) 1.55; AL 4.05, AW 2.42. Carapace (Fig. 1F) brown, uniformly coloured, without distinct pattern. Eye sizes and inter-distances: OAL 0.39, OAW 1.45; AME 0.14, ALE 0.16, PME 0.16, PLE 0.17; AME–AME 0.27, AME–ALE 0.27, PME–PME 0.36, PME–PLE 0.35; MOQA 0.56, MOQP 0.67, CLL 0.10. Chelicerae protruding and reddish brown, with 3 teeth on promargin and 3 on retromargin respectively. Sternum dark brown, STL 1.69, STW 1.44. Labium and endites brown. Legs yellowish-white, without distinct colour markings. Leg measurements: I 18.84 (4.65, 1.22, 5.10, 5.60, 2.26), II 12.09 (3.30, 1.14, 3.24, 3.23, 1.19), III 8.61 (2.38, 0.86, 1.92, 2.40, 1.05), IV 12.47 (3.72, 0.95, 3.17, 4.00, 1.07); LL:CL 5.03. Leg spines: I 0-0-1p, 2v-1v-1p, 2v1p-1p1v-1v; II 0-0-1p, 1v-2v-1p, 2v1p-1v1p-1v; III 0-0-1p1r, 0-1p1r-0, 2v1p-1p1r-1v2p2r; IV 0-0-1p1r, 1v-1v1p-0, 2v1p-1v1p1r-1v2p2r. Abdomen (Fig. 1F) elongate-oval, dorsally grey, dorsum with indistinct heart-shaped mark and two pairs of not obvious muscle depressions; venter brownish without distinct pattern.

Palp (Fig. 1 A–C). Tibia extremely long, about as long as cymbium, with two apophyses; retrolateral tibial apophysis (RTA) about 20% of tibia length, with a more or less bifurcate apex and hiding behind tegulum; prolateral tibial apophysis (PTA) small and round; cymbial spur (CS) is approximately equal in length to tibia, tapering off into a filiform; cymbial fold (CF) poorly developed, for approximately 4/5 the length of cymbium; tip of cymbium short, about 1/4 of cymbium length. Tegulum oblong, 1.3 times longer than wide; tegular apophysis (TA) long and sinuate, more than 4/5 of tegulum length, filamentous and like an ear’s contour in ventral view; embolus (E) arising at approximately 10 o’clock position, terminating at approximately 11 o’clock position, it’s tip covered by conductor (C); conductor large, falciform.

Female. Total length 8.66-9.30. Slightly larger in size and lighter in colour. Allotype (Fig. 1 D–E, G) measured: TL 9.30; CL = 3.03, CW = 2.22, CI (CL/CW) = 1.36; AL = 4.95, AW = 2.92. Eye diameters and inter-distances: OAL 0.37, OAW 1.23; AME 0.14, ALE 0.19, PME 0.13, PLE 0.14; AME–AME 0.23, AME–ALE 0.11, PME–PME 0.31, PME–PLE 0.23; MOQA 0.46, MOQP 0.58, CLL 0.24. PMT: RMT = 6:6.STL 1.47, STW 1.23. Leg measurements: I 12.70 (3.30, 1.06, 3.42, 3.39, 1.54), II 8.51 (2.42, 0.86, 2.23, 2.05, 0.96), III 6.42 (1.92, 0.69, 1.35, 1.65, 0.80), IV 9.67 (2.75, 0.89, 2.39, 2.68, 0.96); LL:CL 4.19. Leg spines: I 0-1p-1p, 2v-2v-0, 2v-1p1r-1v; II 0-0-1p, 1v-2v-1p, 2v1p-1p1r-1v; III 0-1p-1p1r, 1v-1p1r-0, 2v1p1r-1p1r-1v2p2r; IV 0-0-1p1r, 1v-1v1p1r-0, 2v1p1r-1v1p1r-1v2p2r.

Epigyne (Fig. 1 D–E). Atrium (A) indistinct, without delimited margin, about four times wider than long; receptacles (R) are faintly visible through epigynal plate in ventral view; two copulatory openings (CO) located at lateral borders of atrium; the transparent copulatory ducts (CD) running spirally (length of spira about 1.4 times longer than receptacles), forming 7 entwined loops (including 4 ascending coils and 3 descending coils); receptacle sickle-shaped, separated by three diameters.

Distribution.

Presently known only from the type locality, Jinggang Mountains, Jiangxi, China (Fig. 5).