Chrysso bicuspidata, Zhang, Bao-Shi & Zhang, Feng, 2012

Zhang, Bao-Shi & Zhang, Feng, 2012, Two new spider species of the genus Chrysso O. P. - Cambridge, 1882 (Araneae, Theridiidae) in Hainan Island, China, ZooKeys 190, pp. 21-31 : 23-24

Chrysso bicuspidata sp. n. Figs 7-12

Type material.

Holotype ♂, CHINA, Hainan Island: Jianfengling Mountain, 29 May 2009, C. Zhang leg. Paratypes: 2 ♀, same data as holotype; 3 ♀, Jianfengling Mountain, 12 November 2008, G.X. Han leg.; 3 ♂, 1 ♀, Bawangling Mountain (19°07'N, 109°04'E), 25 May 2009, C. Zhang leg.; 5 ♀, Bawangling Mountain, 7 November 2008, G.X. Han leg.; 2 ♂, 1 ♀, Diaoluo Mountain (18°45'N, 109°45'E), 6 June 2009, C. Zhang leg.; 1 ♂, 2 ♀, Limu Mountain, 19 August 2007, F. Zhang leg.

Diagnosis.

Males can be distinguished from most Chrysso species by membranous conductor, wider embolus and acuate apex of cymbium. And it resembles Chrysso cyclocera Zhu, 1998 and Chrysso oxycera Zhu & Song, 1993 in the general shape of the palpal organ, but differs from them by the wider embolus (Figs 8-9). Females differ from all other Chrysso species except Chrysso viridiventris Yoshida, 1996 by the epigynum with a big atrium and a large posterior lobe. It differs from Chrysso viridiventris by the bigger spermathecae and shorter copulatory ducts (Figs 10-12).

Etymology.

The species name refers to the shape of embolic tip.

Description.

Male (holotype). Total length 1.84: cephalothorax 0.92 long, 0.71 wide; abdomen 0.92 long, 0.82 wide, 0.92 high. Carapace longer than wide, yellowish, lateral margin with thin black striations, anterior median with a triangular black patch. Only anterior part with several gray setae. Cervical groove yellowish. Median furrow yellowish, almost triangle. Each eye with a black ring. Both the eye rows recurved from dorsal view (Fig. 7). Diameters of eyes: AME 0.05, ALE 0.04, PME 0.04, PLE 0.04. Interdistances of eyes: AME–AME 0.10, AME–ALE 0.03, ALE–ALE 0.33, PME–PME 0.10, PME–PLE 0.08, PLE–PLE 0.38, ALE and PLE closed to each other. MOA long 0.13, front width 0.18, back width 0.18. Clypeus 0.20 high and furnished with few short gray setae. Chelicerae armed with sparse gray setae, promargin with 2 teeth, fangs short and thin. Endites, labium and sternum yellowish. Anterior margin of endites armed with gray scopula. Sternum furnished with sparse gray setae. Legs yellowish, the end of tibia with gray spots. Measurements of legs: leg I 7.14 (1.94, 0.41, 1.94, 1.63, 1.22), II 3.69 (1.33, 0.31, 0.82, 0.82, 0.41), III 2.14 (0.71, 0.20, 0.31, 0.61, 0.31), IV 3.86 (1.12, 0.31, 0.82, 1.20, 0.41). Leg formula: 1423.

Abdomen oval, longer than wide and armed with brown setae. Dorsum yellowish, anterior part with a pair of black patches (Fig. 7). Venter yellowish. Spinnerets yellowish.

Apical cymbium of male palp acuate; embolus big, thick, and end with a thin ramus; conductor membranous, falciform from ventral view; apex of median apophysis with some small tubers (Figs 8-9).

Female (one paratype from Limu Mountain) total length 2.32: cephalothorax 0.92 long, 0.71 wide; abdomen 1.43 long, 1.22 wide, 1.43 high. Diameters of eyes: AME 0.05, ALE 0.05, PME 0.03, PLE 0.05. Interdistances of eyes: AME–AME 0.05, AME–ALE 0.02, ALE–ALE 0.30, PME–PME 0.09, PME–PLE 0.08, PLE–PLE 0.33, ALE and PLE closed to each other. MOA long 0.13, front width 0.15, back width 0.15. Clypeus 0.30 high. Measurements of legs: leg I 7.75 (2.24, 0.51, 1.94, 2.35, 0.71), II 3.59 (1.24, 0.31, 0.71, 0.92, 0.41), III 2.04 (0.71, 0.20, 0.31, 0.51, 0.31), IV 3.79 (1.24, 0.31, 0.81, 1.02, 0.41). Leg formula: 1423. Dorsal abdomen yellowish. Other characters as in holotype.

Female genitalia lightly sclerotized, and with a circular atrium and a large posterior lobe; spermathecae big, oval; copulatory ducts short, thick and connected with spermathecae from anterior part; each fertilization duct with a global head (Figs 10-12).

The new species with putative Chrysso synapomorphies as follow:(1) carapace pars stridens smooth; (2) abdomen extending beyond spinnerets; (3) cymbial hood of male palp broad; (4) subconductor of male palp present; (5) median apophysis of male palp with apophysis; (6) palpal claw of female dentition sparse; (7) anterior margin of female genital atrium medially acute.

Variation.

The anterior part of dorsal abdomen of some species examined with a pair of black patches, some species without. Males total body length from 1.73-1.88, females total length from 2.22-2.35.

Distribution.

China (Hainan).