Baiyuerius Zhao, B. Li & S. Li, 2023

Zhao, Zhe, Li, Bing, Zhang, Xiaoqing, Ballarin, Francesco, Pham, Dinh-Sac & Li, Shuqiang, 2023, Baiyuerius gen. nov., a new genus of Coelotinae (Araneae, Agelenidae) spiders from China and Vietnam, ZooKeys 1165, pp. 43-60 : 43

Genus Baiyuerius Zhao, B. Li & S. Li gen. nov.

Figs 2 , 3 , 4 , 5 , 6 , 7 , 8

Type species.

Baiyuerius zuojiang Zhao, B. Li & S. Li, sp. nov., from Chongzuo, Guangxi Zhuang Autonomous Region, China.

Etymology.

The generic name is derived from the pinyin word “Baiyue”, referring to the Baiyue region where the new genus is distributed. Baiyue, a loose term dating back to the first millennium BC, was used to denote various populations who inhabited southern China and northern Vietnam. The postfix “-rius” refers to the postfix commonly used in the genera of the Sinodraconarius clade. The gender is masculine.

Diagnosis.

The morphological characteristics of Baiyuerius gen. nov. resemble those of Yunguirius , which is the closest genus to Baiyuerius gen. nov., by the dark color of the carapace, endites and labium; tibia longer than patella of male palp; dorsal apophysis of conductor large; embolus thick with swollen base; copulatory ducts membranous, arising posteriorly, along the contour of epigynal atrium. However, it can be distinguished from Yunguirius as follows: 1) the base of cymbium enlarged, with 1 or 2 hypophyses (Figs 3C , 5C , 6C ) vs. without any hypophysis in Yunguirius ; 2) an atrium located anteriorly and occupying less than or equal to 1/2 of the epigyne (Figs 2A , 4A , 7A ) vs. located centrally and occupying more than 1/2 of the epigyne in Yunguirius (figs 2A, 3A, 4A in Li et al. 2023); and 3) the simple spermathecae (Figs 2B , 4B , 7B ) vs. spermathecal heads long and continuous with its copulatory ducts in Yunguirius (figs 2B, 3B, 4B in Li et al. 2023).

Description.

Medium-sized, total lengths from 8.60 to 11.98. Carapace black turning brown or brown turning yellow-brown, pear-shaped, with longitudinal fovea and darker radial grooves; chelicerae as the same color as the anterior carapace, with three promarginal and two retromarginal teeth; endites and labium dark brown or grey, anteriorly white with black hairs; sternum brown or milk-white, longer than wide. Abdomen yellow-brown, covered with grey hairs, with two pairs of apodemes and four darker chevron-like markings. Spinnerets lighter than sternum in color. Leg formula 4> 1> 2> 3. Male palp: femur more than 3 times than patella, patella approx. half of tibia, patellar apophysis thick and enlarged, finger-like, longer than half of tibia and extending over patella, retrolateral tibial apophysis rectangular and lamellar, extending beyond tibia, lateral tibial apophysis of the same shape as patellar apophysis but thinner and shorter, median apophysis spoon-shaped, length of cymbial furrow c. 1/2 length of cymbium, with an enlarged base, the base of cymbium with 1 or 2 hypophyses, embolus widen and slightly elongated, anterior widest, dorsal apophysis of conductor large and in different shapes, in some cases bearing a jagged margin; Female epigyne: epigynal teeth absent, atrium located anteriorly, over the swell of epigyne, internally milk-white, occupying more than or equal to 1/4 of the female epigyne, posterior epigynal sclerite varying in shape and between two swollen parts of epigyne, copulatory ducts beginning at the posterior margin of epigyne, extended anteriorly, copulatory opening located anterolaterally, spermathecae small and located posteriorly, shorter than 1/4 the length of its copulatory ducts, anterior part fist-like, while its base close to each other, fertilization ducts originating from inside of spermathecae.

Distribution.

Guizhou and Guangdong Province, Guangxi Zhuang Autonomous Region, China and Vinh Phuc Province, Vietnam (Fig. 8 ).

Figures

Figure 2. Epigyne and habitus of Baiyuerius daxi sp. nov. A epigyne, ventral view B vulva, dorsal view C female habitus, dorsal view D female habitus, ventral view E female habitus, lateral view. Scale bar equal for C-E. Abbreviations: A = atrium; CD = copulatory duct; CO = copulatory opening; FD = fertilization duct (white dotted lines); H = hood; PES = posterior epigynal sclerite; S = spermatheca; SE = swell of epigyne.

Figure 3. Left male palp of Baiyuerius pindong sp. nov. A prolateral view B ventral view C retrolateral view (red arrows = hypophyses of cymbium). Scale bar equal for A-C. Abbreviations: C = conductor; CDA = dorsal apophysis of conductor; CF = cymbial furrow; E = embolus; EB = embolic base; LTA = lateral tibial apophysis; MA = median apophysis; PA = patellar apophysis; RTA = retrolateral tibial apophysis; ST = subtegulum; T = tegulum.

Figure 4. Epigyne and habitus of Baiyuerius tamdao sp. nov. A epigyne, ventral view B vulva, dorsal view C female habitus, dorsal view D female habitus, ventral view E female habitus, lateral view. Scale bar equal for C-E. Abbreviations: A = atrium; CD = copulatory duct (black dotted lines); CO = copulatory opening; FD = fertilization duct (white dotted lines); H = hood; PES = posterior epigynal sclerite; S = spermatheca; SE = swell of epigyne.

Figure 5. Left male palp of Baiyuerius zhuping sp. nov. A prolateral view B ventral view C retrolateral view (red arrow = hypophysis of cymbium). Scale bar equal for A-C. Abbreviations: C = conductor; CDA = dorsal apophysis of conductor; CF = cymbial furrow; E = embolus; EB = embolic base; LTA = lateral tibial apophysis; MA = median apophysis; PA = patellar apophysis; RTA = retrolateral tibial apophysis; ST = subtegulum; T = tegulum.

Figure 6. Left male palp of Baiyuerius zuojiang sp. nov. A prolateral view B ventral view C retrolateral view (red arrow: hypophysis of cymbium). Scale bar equal for A-C. Abbreviations: C = conductor; CDA = dorsal apophysis of conductor; CF = cymbial furrow; E = embolus; EB = embolic base; LTA = lateral tibial apophysis; MA = median apophysis; PA = patellar apophysis; RTA = retrolateral tibial apophysis; ST = subtegulum; T = tegulum.

Figure 7. Epigyne and habitus of Baiyuerius zuojiang sp. nov. A epigyne, ventral view B vulva, dorsal view C male habitus, dorsal view D female habitus, dorsal view E female habitus, ventral view; Scale bar equal for C-E. Abbreviations: A = atrium; CD = copulatory duct; CO = copulatory opening; FD = fertilization duct (white dotted lines); H = hood; PES = posterior epigynal sclerite; S = spermatheca; SE = swell of epigyne.

Figure 8. Localities of Baiyuerius species in China and Vietnam 1 B. daxi sp. nov. 2 B. pindong sp. nov. 3 B. tamdao sp. nov. 4 B. zhuping sp. nov. 5 B. zuojiang sp. nov.