Jacaena guiyang Yang, Yu & Zhong, 2023

Yang, Weicheng, Deng, Langju, Yu, Hao & Zhong, Yang, 2023, A new species of Jacaena Thorell, 1897 (Araneae: Liocranidae) from Guiyang southwestern China, Zootaxa 5339 (2), pp. 185-195 : 186-194

Jacaena guiyang Yang, Yu & Zhong , sp. nov.

Figs 1–6

Type material. Holotype J: CHINA: Guizhou Province: Guiyang City, Yunyan District, Luchongguan Forest Park (26.63ºN, 106.70ºE, 1310 m a.s.l.), 4.VI.2022, leg. Hao Yu and Qianle Lu et al. (MGNU-LIO-22-001, YHGY103 ).

Paratypes: CHINA: Guizhou Province: Guiyang City, Wudang District, Qingrengu Scenic Spot (26.61ºN, 106.80ºE, 1088 m a.s.l.), 9.VIII.2021, leg. Hao Yu and Qianle Lu, 2♀ f (MGNU-LIO-22-003~004, MGNU-LIO-22- 003 chosen as voucher YHGY104 ); same data as holotype, 1♁ (MGNU-LIO-22-002) .

Etymology. The species name is derived from the type locality; noun in apposition.

Diagnosis. The male of J. guiyang sp. nov. can be easily distinguished from other congeners, except J. aspera Mu & Zhang, 2020 , by the tegular apophysis with a very rough and granulated surface ( Figs 3A, C, D ; Mu & Zhang 2020: figs 2F, 3C–E), whereas not granulated in all other Jacaena species. It differs from J. aspera by the: (1) sperm duct on the tegulum distinct (vs. indistinct) (cf. Figs 3A, C, D and Mu & Zhang 2020: figs 3C–E); (2) tegular apophysis narrower and longer (vs. wider and shorter) (cf. Figs 3A , 4A and Mu & Zhang 2020: fig. 3D); and (3) conductor located ventrally to embolus (vs. behind embolus) (cf. Figs 4A, B, D and Mu & Zhang 2020: fig. 3D). The female of J. guiyang sp. nov. also resembles that of J. aspera in having copulatory ducts packed in several coils, but they can be separated by the different number of coils (2.5 coils in J. guiyang sp. nov. instead of 3.5 coils in J. aspera ) (cf. Figs 5B, D and Mu & Zhang 2020: fig. 3B). In addition, the two species can by separated by their habitus: for the males, abdomen dorsally with a W-shaped band in J. guiyang sp. nov., but with a inverted V-shaped band in J. aspera (cf. Fig. 6A and Mu & Zhang 2020: fig. 1D); for the females, abdomen dorsally gray and with three pairs of muscular impressions in J. guiyang sp. nov., whereas black with two pairs of muscular impressions in J. aspera (cf. Fig. 6D and Mu & Zhang 2020: fig. 1E).

Description. Male (holotype, MGU-LIO-22-001). Total body length 5.56: carapace 2.86 long, 2.28 wide; abdomen 2.70 long, 1.71 wide. Color of the living holotype male was basically dark except brown patella, tibia, metatarsus and tarsus, abdomen dorsally with three transverse yellow stripes ( Fig. 2A ). Habitus in ethanol ( Figs 5E , 6 A−C): carapace black ( Figs 5E , 6A, C ), surface granulated, nearly hexagonal in dorsal view, cephalic region distinctly narrowed, widest between coxae II and III. Eye sizes and interdistances: AME 0.11, ALE 0.12, PME 0.09, PLE 0.12; AME–AME 0.10, AME−ALE 0.04, PME–PME 0.13, PME−PLE 0.15; MOA 0.33 long, anterior width 0.32, posterior width 0.31. Clypeal height 0.26. Mouthparts ( Figs 5E , 6B ): chelicerae dark deep red-brown, robust, both promargin and retromargin with two teeth; endite coloured as chelicerae, length 0.77, width 0.37; labium nearly trapezoidal, proximally black, distally deep red-brown and with maxillar hair tuft, slightly longer than wide (0.45: 0.38). Sternum ( Fig. 6B ) length 1.49, width 1.23; dark brown, shield-shaped; anterior margin truncated; lateral margins strongly delimited, with intercoxal sclerites between coxae I and II, II and III, III and IV; precoxal triangles present; posterior region protruding between coxae IV. Legs ( Fig. 2A ): all legs proximally black (coxae, trochanters and femora), distally deep red-brown (patellae, tibiae, metatarsi and tarsi). Leg measurements: I 8.71 (2.10, 2.64, 1.65, 0.82); II 6.71 (1.93, 2.46, 1.47, 0.85); III 6.23 (2.00, 1.91, 1.44, 0.88); IV 8.69 (2.61, 2.76, 2.18, 1.14). Pedicel ( Fig. 6A ) cylindrical, sclerotized, relatively short, red-brown. Abdomen light black ( Figs 6 A−C), scutum small, indistinct; dorsum with W-shaped transverse yellow bands; venter with trapezoidal pattern centrally.

Palp ( Figs 3 , 4 ): Tibia relatively short, about 1/3 of cymbium length. Retrolateral tibial apophysis (RTA) with two processes: dorsal one (dRTA) relatively broad and triangular, approximately 5/6 of palpal tibia width; prolateral apophysis (pRTA) narrow, thumb-like, about 1/2 of palpal tibia length, with partly-membranous and slightly curved apex. Cymbium (Cy) ovoid, nearly 1.9 times longer than wide, dorsally with dense hairs. Tegulum (Te) approximately 1.5 times as long as its maximum width in ventral view; subtegulum (St) sclerotized, retrolateral margin distinct; sperm duct (SD) distinct, forming an unclosed loop in ventral view. Tegular apophysis (TA) claw-shaped, surface strongly rough and granulated, about 1/3 of tegulum length, originating from approximately 12 o’clock on tegulum; base wide, tapering to sharp and distinctly curved tip. Embolar base (EB) partly-membranous, originating from 10–11 o’clock relative of tegulum; free part of embolus (Em) filamentous and distinctly long, obliquely coiled; embolar tip (ET) curved behind tegular apophysis, terminating at approximately 11 o’clock position. Conductor (C) membranous indistinct, extending along with tegular apophysis.

Female (Paratype, MGNU-LIO-22-003). Total body length 4.77: carapace 2.16 long, 1.68 wide; abdomen 2.61 long, 1.69 wide. Habitus in ethanol ( Figs 5F , 6D–F ): carapace dark brown. Eye sizes and interdistances: AME 0.11, ALE 0.12, PME 0.09, PLE 0.13; AME–AME 0.09, AME–ALE 0.05, PME–PME 0.13, PME–PLE 0.13; MOA 0.30 long, anterior width 0.31, posterior width 0.31. Clypeal height 0.18. Leg I 5.90 (1.61, 2.00, 1.42, 0.87); II 6.37 (1.86, 2.27, 1.39, 0.85); III 5.96 (1.63, 2.00, 1.44, 0.89); IV 8.14 (2.24, 2.67, 2.31, 0.92). Abdomen ovoid and gray, without dorsal scutum, with three pairs of muscular impressions centrally. Venter of abdomen yellowish white. Other characters as in male.

Epigyne ( Figs 5 A−D): Epigynal plate nearly as wide as long, lateral and posterior margins indistinct. Copulatory openings (CO) large and circular, located at anterior of epigynal plate. Copulatory ducts (CD) long and tapered off, strongly convoluted, forming 2.5 entwined loops, leading to large spermathecae and acicular, membranous fertilisation ducts (FD). Spermathecae (Sp) located posteriorly, globular and small, separated by about 2 times their diameters.

Habitat and biology. The holotype of J. guiyang sp. nov. was obtained from foliage in bush close to a small pavement in the core zone of Luchongguan Forest Park ( Fig. 2B ). The female paratypes were obtained from shrubs close to a small stream in Qingrengu Scenic Spot ( Fig. 2C ). All types were collected by beating vegetation.

Phylogenetic relationships. The sequence of the cythochrome oxidase I gene was almost identical in the two individuals of both sexes of J. guiyang sp. nov. (the divergence was about 1.5%). The divergence with respect to the closest species ( J. schwendingeri ( Deeleman-Reinhold, 2001)) was 15.5% and 15.2%, respectively (see Table 2 ). In conclusion, we credibly matched the females and males together based on DNA barcoding data.

Distribution. Known only from the type locality, Guiyang City, Guizhou, China ( Fig. 1 ).

Figures

FIGURE 1. Collection locality of Jacaena guiyang sp. nov. A. Locality of Guizhou Province in China. B. Locality of Guiyang City in Guizhou Province. C. Distribution records of Jacaena guiyang sp. nov. in Guiyang City.

FIGURE 2. Jacaena guiyang sp. nov., live specimen and habitat. A. Male holotype from Lu Chong Guan Forest Park. B. Habitat of male holotype, Luchongguan Forest Park. C. Habitat of female paratypes, Qingrengu Scenic Spot. Photographs by Qianle Lu (Shenzhen, Guangdong).

FIGURE 3. Jacaena guiyang sp. nov., male holotype, left palp. A. Ventral view. B. Dorsal view. C. Prolateral view. D. Retrolateral view.Abbreviations: C = conductor; Cy = cymbium; EB = embolar base; Em = embolus; ET= embolar tip; dRTA = distal process of retrolateral tibial apophysis; pRTA = proximal process of retrolateral tibial apophysis; SD = sperm duct; St = subtegulum; TA = tegular apophysis; Te = tegulum. Scale bars: 0.2 mm (A–D).

FIGURE 4. Jacaena guiyang sp. nov., male holotype, left palpal bulb. A. Ventral view. B. Dorsal view. C. Prolateral view. D. Retrolateral view. Abbreviations: C = conductor; EB = embolar base; Em = embolus; ET= embolar tip; SD = sperm duct; St = subtegulum; TA = tegular apophysis; Te = tegulum. Scale bars: 0.2 mm (A–D).

FIGURE 5. Jacaena guiyang sp. nov., female paratype and male holotype, epigyne (A–D) and frontal views of prosoma (E, F). A–B. Macerated epigyne, ventral and dorsal. C–D. Epigyne, macerated and embedded in Arabic gum, ventral and dorsal (dashed line in D showing schematic course of copulatory duct, dorsal). E. Male. F. Female. Abbreviations: CD = copulatory duct; CO = copulatory opening; FD = fertilisation duct; Sp = spermatheca. Scale bars: 0.2 mm (A–D); 1 mm (E–F).

FIGURE 6. Habitus of Jacaena guiyang sp. nov., male holotype (A–C) and female paratype (D–F). A, C. Dorsal view. B, E. Ventral view. C, F. Lateral view. Arrows point to dorsal abdominal scutum. Scale bars: 1 mm (A–C, D–F).