Chrysso bifurca, 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 : 22-23

Chrysso bifurca sp. n. Figs 1-6

Type material.

Holotype ♂, CHINA, Hainan Island: Jianfengling Mountain (19°07'N, 109°13'E), 29 May 2009, C. Zhang leg. Paratypes: 2 ♀, same data as holotype; 1 ♀, Limu Mountain (19°10'N, 109°39'E), 20 August 2007, C. Zhang leg.; 3 ♂, 12 ♀, Limu Mountain, 20 November 2008, G.X. Han leg.

Diagnosis. Males can be distinguished from other Chrysso species by the following characters: apex of cymbium bifurcate; embolus short and thin; theridiid tegular apophysis erect, with obtuse apex (Figs 3-4). Females differ from other Chrysso species by the bigger and oval spermathecae, and the longer and winding copulatory ducts, differ from Chrysso octomaculata ( Bösenberg & Strand, 1906) by the process of copulatory ducts (Fig. 6).

Etymology.

The species name refers to bifurcate apex of cymbium.

Description.

Male (holotype). Total length 2.70: cephalothorax 1.26 long, 1.08 wide; abdomen 1.44 long, 0.99 wide, 0.90 high. Carapace yellow, longer than wide, lateral margin with thin black striations. Only anterior part with several gray setae. Cervical groove distinct. Median furrow almost triangle, yellowish. Each eye with a black ring. Both the eye rows recurved from dorsal view (Fig. 1). Diameters of eyes: AME 0.12, ALE 0.10, PME 0.10, PLE 0.10. Interdistances of eyes: AME–AME 0.10, AME–ALE 0.08, ALE–ALE 0.64, PME–PME 0.10, PME–PLE 0.14, PLE–PLE 0.66, ALE and PLE closed to each other. MOA long 0.29, front width 0.34, back width 0.31. Clypeus 0.32 high, yellow and furnished with few short gray setae. Chelicerae armed with sparse gray setae, promargin with 2 teeth, fangs short and thin. Anterior margin of endites armed with gray scopula. Labium armed with sparse long black setae. Sternum furnished with sparse black setae, its anterior margin lightly procurved. Legs yellow, patella, metatarsus and the base of femur and tibia reddish-brown. Measurements of legs: leg I 9.44 (2.52, 0.59, 2.55, 2.88, 0.90), II 4.38 (1.49, 0.45, 1.13, 0.90, 0.41), III 3.16 (0.90, 0.36, 0.59, 0.90, 0.41), IV 5.09 (1.58, 0.36, 1.17, 1.44, 0.54). Leg formula: 1423.

Abdomen oval, longer than wide and armed with brown setae. Dorsum yellowish, armed with six pairs of irregular black patches, posterior with a median black patch (Figs 1-2). Venter yellowish, with a black median patch. Anal tubercle yellow. Spinnerets yellow.

Male palp with long cymbium, apical part of cymbium bifurcate; embolus short, base with a lunate process, distal part thin; theridiid tegular apophysis erect, with wide base, apex thin and obtuse; conductor lying behind theridiid tegular apophysis (Figs 3-4).

Female (one paratype from Jianfengling Mountain) total length 3.33: cephalothorax 0.95 long, 0.94 wide; abdomen 2.34 long, 1.62 wide, 1.58 high. Diameters of eyes: AME 0.12, ALE 0.10, PME 0.10, PLE 0.10. Interdistances of eyes: AME–AME 0.13, AME–ALE 0.09, ALE–ALE 0.59, PME–PME 0.14, PME–PLE 0.16, PLE–PLE 0.61, ALE and PLE closed to each other. MOA long 0.27, front width 0.30, back width 0.31. Clypeus 0.32 high. Measurements of legs: leg I10.81 (3.24, 0.63, 2.70, 3.29, 0.95), II 6.44 (2.03, 0.54, 1.44, 1.80, 0.63), III 3.52 (1.13, 0.41, 0.63, 0.90, 0.45), IV 7.08 (1.94, 0.54, 2.21, 1.80, 0.59). Leg formula: 1423. Other characters as in holotype.

Female genitalia lightly sclerotized, posterior part with a kidney-shaped atrium; spermathecae big, oval; copulatory ducts long, thick, winding and connected with spermathecae from posterior part (Figs 5-6).

The new species with putative Chrysso synapomorphies as follow:(1) carapace pars stridens irregular; (2) abdomen extending beyond spinnerets; (3) cymbial hood of male palp broad; (4) median apophysis of male palp with distinct apophysis; (5) palpal claw of female dentition sparse.

Variation.

The lateral part of dorsal abdomen of some females examined with eight to eleven pairs of irregular black patches. Males total body length from 2.64-2.80, female total length from 3.28-3.35.

Distribution.

China (Hainan).