Cheiracanthium circulum, Zhang, 2023

Li, Zhaoyi & Zhang, Feng, 2023, Five new species of the long-legged sac spider genus Cheiracanthium C. L. Koch, 1839 (Araneae: Cheiracanthiidae) from China, European Journal of Taxonomy 900, pp. 81-105 : 88-92

Cheiracanthium circulum sp. nov.

urn:lsid:zoobank.org:act:337E422F-6B3F-459F-BD13-A85167F0F4E7

Figs 3–4 , 11 , Table 1

Diagnosis

The male of this new species ( Fig. 4C–E ) is similar to C. uncinatum Paik, 1985 (Zhang & Zhu 1993: 77, figs 3–6) in having a beak-shaped cymbial spur and a semicircular embolus, but can be distinguished by: (1) the shorter DTA; (2) the thinner median apophysis; (3) the circular tegulum (vs. longitudinally oval in C. uncinatum ). The female can be easily distinguished from all other species of Cheiracanthium by the dumbbell-shaped spermathecae and arch-shaped anterior margin ( Fig. 4A–B ).

Etymology

The specific epithet is an adjective from the Latin ‘ circulus ’, referring to the circular tegulum in ventral view.

Type material

Holotype CHINA • ♂; Yunnan Province, Baoshan City, Longling County, Longxin Town , Xiaoheishan Nature Reserve ; 16 Feb. 2011; L.Y. Wang leg.; voucher code: ZYL130, Genbank: OQ866250 ; MHBUARA-1005 .

Paratype CHINA • 1 ♀; Yunnan Province, Lushui City, Pianma Town ; 9 May. 2004; Z.Z. Yang leg.; voucher code: ZYL122, Genbank: OQ866243 ; MHBU-ARA-1006 .

Description

Male (holotype)

MEASUREMENTS. Total length 6.63. Carapace 3.01 long, 2.31 wide; abdomen 3.62 long, 2.35 wide. Eye sizes and interdistances: AME 0.12, ALE 0.12, PME 0.13, PLE 0.13; AME–AME 0.18, AME–ALE 0.19, PME–PME 0.22, PME–PLE 0.25. MOA 0.47 long, front width 0.43, back width 0.55. Clypeus height 0.07. Sternum 1.45 long, 1.18 wide. Leg measurements: I missing, II 11.09 (2.94, 0.77, 2.96, 3.28, 1.14), III 8.70 (2.22, 0.62, 2.23, 2.65, 0.98), IV 11.29 (2.75, 0.87, 2.88, 3.54, 1.25).

BODY ( FIG. 3A–B ). Prosoma with distinct radial striae, cephalic region yellow, thoracic region yellowish brown. All eyes with black rings, AER slightly recurved in frontal view; PER slightly wider than AER, almost straight in dorsal view. Chelicerae yellowish brown, with 3 promarginal and 4 retromarginal teeth. Sternum yellowish brown. Labium and endites colored as sternum. Legs pale yellow, without distinct markings. Leg spines: I missing ẓ II 1p1r-1p1r-0, 1p-1p2v-1r1v, 1v-1p2v-1p2v; III 1p1r-1p1r-0, 1p1r-1r-1d, 1p1r1v-1p1r2v-2p1r1v; IV 1p1r-1p1r-0, 1p1r-1p1r-1v, 1p2r1d1v-1p1r1d1v-2p1r1v. Opisthosoma elongate-oval, dorsally grey, with scattered white small patches and numerous black hairs, narrow longitudinal band in middle, enclosed by light spots, two pairs of muscular impressions; venter greyish, with sparse white spots. Spinneret coniform, ALS larger and closed each other; PMS smallest; and PLS with two segments, length of distal segment nearly length of base segment.

PALP ( Fig. 4C–E ). Tibia long, ca ⅔ of cymbium’s length; RTA short, ca ¼ of tibia’s length, with wider base and hook-shaped tip, and pointed dorsally from ventral view; DTA slightly shorter than RTA, thin and rodlike; cymbium almost 2 × as long as wide; tip of cymbium long, ca ⅓ of cymbium’s length; cymbium retrolateral margin with shallow dent, cymbial furrow short and shallow; cymbial spur slightly longer than RTA; tegulum circular; median apophysis long, ca ½ of tegulum’s length, with wider base and hook-shaped apex in ventral view; embolus originating on retrolateral flank, at about 3 o’clock position, extending clockwise along tegular margin, tip covered by conductor; conductor membranous, with broad apex; sperm duct indistinct.

Female (paratype)

MEASUREMENTS. Total length 6.96. Carapace 2.98 long, 2.35 wide; abdomen 3.98 long, 2.60 wide. Eye sizes and interdistances: AME 0.15, ALE 0.16, PME 0.14, PLE 0.15; AME–AME 0.23, AME–ALE 0.28, PME–PME 0.32, PME–PLE 0.36. MOA 0.47 long, front width 0.49, back width 0.60. Clypeus height 0.04. Sternum 1.47 long, 1.33 wide. Leg measurements: I 13.03 (3.54, 1.14, 3.49, 3.66, 1.20), II 9.91 (2.76, 0.93, 2.40, 2.75, 1.07), III 7.44 (2.21, 0.64, 1.49, 2.13, 0.97), IV 10.55 (2.96, 0.89, 2.64, 3.00, 1.06).

BODY ( Fig. 3C–D ). Prosoma reddish brown, thoracic region darker than other parts except the eye area. Chelicerae with 3 promarginal and 5 retromarginal teeth. Sternum, labium and endites colored as carapace. Legs pale yellow. Leg spines: I 0-0-0, 0-0-0, 1v-0-2v; II 1p1r-1p-0, 1p-1v-1v, 1v-2v-2v; III 1p1r-1p-0, 1r-1r-1d, 1p1r2v-1v-2v; IV 1r-1p-0, 1r-1p-1v, 1p1r2v-2v-1v. Opisthosoma greyish brown, with scattered white spots and two pairs of muscular impressions.

EPIGYNE ( Fig. 4A–B ). Atrium heavily sclerotized, located at posterior portion of epigynal plate, with arch-shaped anterior margin and crescent-shaped lateral margins; two copulatory openings located at postero-lateral margins of atrium; part of dark copulatory duct and spermathecae visible through tegument of epigynal plate in ventral view; spermathecae dumbbell-shaped, connected with simple copulatory duct, copulatory ducts ascend, then fold backwards and lastly descend to spermathecae.

Distribution

China, Yunnan (localities in Fig. 11 ).

Figures

Fig. 3. Cheiracanthium circulum sp. nov. A–B. ♂, holotype (MHBU-ARA-1005). C–D. ♀, paratype (MHBU-ARA-1006). A, C. Habitus, dorsal view. B, D. Habitus, ventral view.

Fig. 4. Cheiracanthium circulum sp. nov. A–B. ♀, paratype (MHBU-ARA-1006). C–E. ♂, holotype (MHBU-ARA-1005). A. Epigyne, ventral view. B. Vulva, dorsal view. C. Left palp, prolateral view. D. Same, ventral view. E. Same, retrolateral view. Abbreviations: see Material and methods.

Fig. 11. Distribution records of the five new species of Cheiracanthium in China.