Sinostidia shuangjiao Yu & Li, 2021

Zhang, Jianshuang, Yu, Hao & Li, Shuqiang, 2021, On the clubionid spiders (Araneae, Clubionidae) from Xishuangbanna, China, with descriptions of two new genera and seven new species, ZooKeys 1062, pp. 73-122 : 73

Sinostidia shuangjiao Yu & Li sp. nov.

Figs 21 , 22

Type material.

Holotype: ♂ (IZCAS-Ar34738), China: Yunnan: Xishuangbanna: Mengla County: Menglun Town: Menglun Nature Reserve: Anogeissus acuminata plantation (~ 20 years old) (21°53.993'N, 101°16.810'E, 610 m), 19 August 2007, G. Zheng leg. Paratype: 1♀ (IZCAS-Ar34739, YHCLU0155), G213 roadside, Leprosy village (21°53.590'N, 101°17.296'E, 540 m), 4 May 2019, H. Yu leg.

Other material examined.

1♂ (YHCLU0151), same data as the paratype .

Etymology.

The specific name is derived from the Chinese pinyin shuâng ji ǎ o, meaning two-horned, referring to the forked tegular apophysis; noun in apposition.

Diagnosis.

Sinostidia shuangjiao sp. nov. closely resembles S. dujiao sp. nov. (Figs 23 , 24 ) but can be distinguished by the shape of the copulatory organs. Males of the new species differ from those of S. dujiao sp. nov. by: (1) the bifid tip of the tegular apophysis represented by two tooth-shaped apophyses (vs. not bifid) (cf. Figs 21A-E and 23C-E ); (2) the filiform or claw-shaped embolic tip (vs. large and conical, cf. Figs 21B-E and 23B-E ); (3) the conductor is transparent and membranous (vs. thick and partly membranous) (cf. Figs 21D, E and 23D, E ). The female of the new species can be differentiated from S. dujiao sp. nov. by lacking an atrium (vs. atrium present) (cf. Figs 22A, B and 24A, B ), the copulatory openings located laterally on the epigynal plate (vs. located at anterior atrial border) (cf. Figs 22A, B and 24A, B ), and by the globular bursae which are smaller than the spermathecae (vs. reniform burse distinctly larger than the spermathecae) (cf. Figs 22C, D and 24C, D ).

Description.

Male (holotype) (Fig. 22E, F ). Total length 4.73; carapace 1.75 long, 1.49 wide; opisthosoma 2.98 long, 1.16 wide. Carapace pyriform, ocular region distinctly narrowed; light orange, slightly darker frontally, without distinct pattern; fovea reddish. Eyes: AER slightly recurved, PER slightly wider than AER and procurved in dorsal view. AME dark, other eyes light; with black rings. Eye sizes and interdistances: AME 0.09, ALE 0.09, PME 0.12, PLE 0.11, AME-AME 0.03, AME-ALE 0.02, PME-PME 0.14, PME-PLE 0.08, MOQL 0.32, MOQA 0.28, MOQP 0.41. Chelicerae red-brown. Labium and endites light orange. Sternum yellowish white. Legs yellowish orange. Leg measurements: I 7.05 (1.95, 2.91, 1.43, 0.77), II 6.61 (1.86, 2.1, 1.44, 0.70), III 5.27 (1.55, 1.72, 1.44, 0.56), IV 7.67 (2.12, 2.59, 2.23, 0.73). Abdomen (Fig. 22E, F ) lanceolate, dorsum with numerous inconspicuous patches; venter white; all spinnerets without distinct markings.

Palp (Fig. 21A-E ): Retrolateral tibial apophysis claw-shaped, retrolaterally pointed, ~ 1/2 of tibia length, with curved, sharp apex; ventral tibial apophysis pointed anteriorly, thumb-like, ~ 1/3 of tibia length. Bulb oval, ~ 2 × longer than wide, sperm duct indistinct in ventral view. Tegular apophysis large, as long as tegulum width, originating retrolaterally on tegulum, with bifurcated distally, covering embolic base. Embolus claw-shaped, tip extended to apex of cymbium, directed antero-prolaterally; embolic base as long as free (filamentous) part of embolus, represented by enlarged tubercle located prolaterally (~ 10 o’clock relative to tegulum). Conductor membranous, ~ 1/2 embolus length, originating distally on tegulum, base wide, apex narrowed, folded.

Female (paratype IZCAS-Ar34739). Total length 5.60; carapace 2.36 long, 1.74 wide; opisthosoma 3.21 long, 1.54 wide. General characters as in males, but slightly larger and lighter (Fig. 22G, H ). Eye sizes and interdistances: AME 0.11, ALE 0.13, PME 0.13, PLE 0.09, AME-AME 0.06, AME-ALE 0.05, PME-PME 0.21, PME-PLE 0.11, MOQL 0.34, MOQA 0.36, MOQP 0.52. Legs uniformly white. Leg measurements: I 6.97 (1.97, 2.85, 1.38, 0.77), II 6.16 (1.70, 2.43, 1.34, 0.69), III 5.41 (1.66, 1.71, 1.50, 0.53), IV 7.97 (2.01, 2.80, 2.22, 0.95).

Epigyne (Fig. 22A-D ): Plate distinctly wider than long, with shallow depression located anteriorly. Depression broad, width almost equal to the plate width, ellipsoid, ~ 1.6 × wider than long; bounded by numerous, relatively long setae, sparse anteriorly, dense posteriorly and laterally. Copulatory openings small but distinct, located laterally in depression, separated by ~ 15 diameters, leading to short copulatory ducts which descend obliquely to spermathecae. Spermathecae consisting of twisted base and globular head; spermathecal heads separated by 2/3 of their diameter. Bursae globular, close together, translucent. Fertilisation ducts indistinct.

Distribution.

Known only from the type locality.

Figures

Figure 21. Male palp of the holotype of Sinostidia shuangjiao sp. nov. A prolateral view B retrolateral view C bulb, prolateral view D bulb, ventral view E bulb, retrolateral view. Abbreviations: C = conductor; E = embolus; EB = embolic base; RTA = retrolateral tibial apophysis; TA = tegular apophysis; VTA = ventral tibial apophysis. Scale bars: 0.10 mm (equal for A, B, equal for C-E).

Figure 22. Sinostidia shuangjiao sp. nov., female paratype and male holotype, epigyne (A-D), male habitus (E, F) and female habitus (G, H) A intact, ventral view B cleared, ventral view C cleared, dorsal view D cleared, dorsal view E dorsal view F lateral view G dorsal view H ventral view. Abbreviations: BS = bursa; CD = copulatory duct; CO = copulatory opening; SB = spermathecal base; SH = spermathecal head; SP = spermatheca. Scale bars: 0.10 mm (equal for A-D); 1 mm (equal for E, F, equal for G, H).

Figure 23. Male palp of the holotype of Sinostidia dujiao sp. nov. A prolateral view B retrolateral view C bulb, prolateral view D bulb, ventral view E bulb, retrolateral view. Abbreviations: C = conductor; E = embolus; EB = embolic base; RTA = retrolateral tibial apophysis; TA = tegular apophysis; VTA = ventral tibial apophysis. Scale bars: 0.10 mm (equal for A, B, equal for C-E).

Figure 24. Sinostidia dujiao sp. nov., female paratype and male holotype, epigyne (A-D), male habitus (E, F) and female habitus (G, H) A intact, ventral view B cleared, ventral view C cleared, dorsal view D cleared, dorsal view E dorsal view F lateral view G dorsal view H ventral view. Abbreviations: BS = bursa; CD = copulatory duct; CO = copulatory opening; SB = spermathecal base; SH = spermathecal head; SP = spermatheca. Scale bars: 0.10 mm (equal for A-D); 1 mm (equal for E, F, equal for G, H).