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

Wei, Mian, Zhu, Yang, Liu, Jie, Zhang, He & Liu, Fengjie, 2025, New species and new combinations of the spider genus Baiyuerius Zhao, B. Li & S. Q. Li, 2023 (Araneae, Agelenidae, Coelotinae), Zootaxa 5636 (3), pp. 401-442 : 403

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

Type species. Baiyuerius zuojiang Zhao, B. Li & S. Li, 2023

Diagnosis. Baiyuerius resembles Yunguirius B. Li, Zhao & S. Q. Li, 2023 in 1) carapace with high and broad cephalic region, and legs usually red or orange ( Figs 6A, B , 10A, B , 24A, B ; fig. 4A, B in Liu et al. 2020; fig. 4A, B in Luo et al. 2023; fig. 7A, B in Wei et al. 2024); 2) conductor large and crescent, with modified dorsal margin, median apophysis human-ear-shaped ( Fig. 1A–E ; fig. 317 in Wang et al. 2012); 3) epigyne with large atrium, and copulatory ducts with distinct blind sac ( Fig. 2A–D ; figs 2A, B, 8A, B in Wei et al. 2024). But males of Baiyuerius are diagnosed by the process on the dorsal margin of the conductor strongly sclerotized, except of the digitus- group species, which without the process ( Fig. 1A–E ) [vs. weakly sclerotized in the Yunguirius (fig. 317 in Wang et al. 2012)]; 2) embolic base enlarged ( Fig. 1A–E ) [vs. not so large in Yunguirius (fig. 317 in Wang et al. 2012)]. Females are distinguished from those of Yunguirius by 1) atrium without anterior margin, and the epigynal plate without sclerotized structure above atrium ( Fig. 2A, C ) [vs. atrium with or without anterior margin, but the epigynal plate with sclerotized part above atrium (fig. 3A in Zhao et al. 2023; figs 2A, 8A in Wei et al. 2024)]; 2) spermathecae nearly spherical, sometimes with tubercles ( Fig. 2B, D ) [vs. long and divided into two parts (fig. 2B in Zhao et al. 2023; fig. 2B in Wei et al. 2024)].

Key to the Baiyuerius species groups

1. Male............................................................................................... 2 Female (those of cuii and digitus -species groups unknown).................................................... 6

2. Dorsal margin of conductor without modified process ( Fig. 21B )............................... digitus- species group Dorsal margin of conductor with modified process.......................................................... 3

3. Patella with two apophyses ( Figs 17C , 19C ).................................................. cuii -species group Patella with only one apophysis......................................................................... 4

4. Patellar apophysis thick and cylindrical, lateral tibial apophysis expanded and round, conductor dorsal apophysis extremely long ( Figs 27C, D , 31C, E )........................................................... zuojiang -species group Patellar apophysis with pointed tip, lateral tibial apophysis long, with pointed tip, conductor dorsal apophysis short....... 5

5. Process of dorsal margin of conductor strongly sclerotized and divided into two branches, tegular sclerite Y-shaped ( Fig. 1C in Hoang et al. 2023)................................................................... rotulus -species group The process with a distinct basal stalk and separated from dorsal margin of conductor, tegular sclerite not Y-shaped ( Figs 3B , 5B , 11B ).......................................................................... chongzu -species group

6. Epigynal teeth present ( Figs 9A , 13A , 15A ).............................................. chongzu -species group Epigynal teeth absent.................................................................................. 7

7. Epigynal plate large, width of epigynal pocket subequal to length, copulatory ducts long, without blind sacs ( Figs 23A, B , 25A, B )................................................................................ rotulus -species group Epigynal plate relatively small, width of epigynal pocket obviously longer than length, copulatory ducts short, with blind sacs ( Figs 29A, B , 33A, B )............................................................... zuojiang- species group

Figures

FIGURE 1. Male palps of Baiyuerius spp. from different species groups, in ventral view A Baiyuerius arcticus sp. nov. from chongzu-group, (a) cymbial furrow of B. arcticus sp. nov., retrolateral view, and the white arrows point out the extended dorsal margin of the the cymbial furrow B Baiyuerius loong sp. nov. from chongzu-group C Baiyuerius jiquanyui sp. nov. from cuii- group D Baiyuerius digitus sp. nov. from digitus-group E Baiyuerius carcharus sp. nov. from zuojiang-group. The colored areas indicate the different parts of conductors: blue areas indicate the ventral margins, yellow areas indicate the dorsal margins (excluding the modified processes of dorsal margin), green areas indicate the modified processes of dorsal margin, red areas indicate the dorsal apophyses of conductor. The white dashed outlines show the tegular concave. Scale bars: 0.50 mm.

FIGURE 2. Epigynes and internal genitals of Baiyuerius spp. from two species groups. A, B Baiyuerius shaanxiensis sp. nov. from chongzu-group C, D Baiyuerius shenyunxiaoi sp. nov. from rutolus-group A, C epigynes, ventral view B, D internal genitals, dorsal view.Abbreviations:A = atrium; BS = blind sac; CD = copulatory duct; CO = copulatory opening; ET = epigynal teeth; FD = fertilization duct; H = hood; PES = posterior epigynal sclerite; S = spermatheca; SE = swollen epigyne. The colored areas indicate the different part of epigynes: blue areas indicated the epigynal pockets, the yellow areas indicate the atriums. The black dash lines divide the posterior epigynal sclerite and the swollen epigyne. Scale bars: 0.50 mm.

FIGURE 3. Male palp of Baiyueius arcticus sp. nov. A–C left palp D right bulb E conductor of right bulb F left embolic tip. A prolateral view B, F ventral view C retrolateral view D horizontally flipped dorsal view E horizontally flipped apical view. Abbreviations: BL = basal lamellar of conductor dorsal apophysis; C = conductor; CDA = dorsal apophysis of conductor; CDMP = process of dorsal margin of conductor; CF = cymbial furrow; E = embolus; EB = embolic base; EBA = basal apophysis of embolus; EO = embolic opening; LTA = lateral tibial apophysis; MA = median apophysis; PA = patellar apophysis; RTA = retrolateral tibial apophysis; T = tegulum; ST = subtegulum; TS = tegular sclerite. Scale bars: A–C 0.50 mm, D, E 0.25 mm, F 0.05 mm.

FIGURE 5. Male palp of Baiyueius chongzu sp. nov. A–C left palp D, E horizontally flipped right bulb F horizontally flipped right tibia G left embolic tip. A prolateral view B, G ventral view C retrolateral view D dorsal view E apical view G prolateral view. Abbreviations: BL = basal lamellar; C = conductor; CDA = dorsal apophysis of conductor; CDMP = process of dorsal margin of conductor; CF = cymbial furrow; EB = embolic base; Em = embolus; LTA = lateral tibial apophysis; MA = median apophysis; PA = patellar apophysis; PTA = prolateral tibial apophysis; RTA = retrolateral tibial apophysis; ST = subtegulum; T = tegulum; TS = tegular sclerite. Scale bars: A–C 0.50 mm, D–F 0.25mm, G 0.05mm.

FIGURE 6. Characters of the male of Baiyuerius chongzu sp. nov. A habitus, dorsal view B habitus, prolateral view C eye area, frontal view D eye area, dorsal view E cephalic rigion, lateral view. Scale bars: A, B 2.00 mm, C, D 0.50 mm, E 0.25 mm.

FIGURE 9. Epigyne and internal genitalia of Baiyuerius imitatus sp. nov. A epigyne, ventral view B internal genitalia, dorsal view. Abbreviations: A = atrium; BS = blind sac; CD = copulatory duct; CO = copulatory opening; ET = epigynal teeth; FD = fertilization duct; H = hood; PES = posterior epigynal sclerite; S = spermatheca; SE = swollen epigyne; SH = spermathecal head. Scale bar: 0.50 mm.

FIGURE 10. Characters of the female of Baiyuerius imitatus sp. nov. A habitus, dorsal view B habitus, prolateral view C eye area, frontal view D eye area, dorsal view E cephalic rigion, lateral view. Scale bars: A, B 2.00 mm, C, D 0.50 mm, E 0.25 mm.

FIGURE 11. Male palp of Baiyueius loong sp. nov. A–C left palp D, E horizontally flipped right bulb F left embolic tip. A prolateral view B, F ventral view C retrolateral view D apical view E dorsal view.Abbreviations: C = conductor; CDA = dorsal apophysis of conductor; CDMP = process of dorsal margin of conductor; CEBA = ecto-basal apophysis of cymbium; CF = cymbial furrow; CyDA = dorsal apophysis of cymbium; E = embolus; EB = embolic base; LTA = lateral tibial apophysis; MA = median apophysis; PA = patellar apophysis; RTA = retrolateral tibial apophysis; T = tegulum; ST = subtegulum; TS = tegular sclerite. Scale bars: A–C 0.50 mm, D, E 0.25 mm, F 0.05 mm.

FIGURE 13. Epigyne and internal genitalia of Baiyuerius loong sp. nov. A epigyne, ventral view B internal genitalia, dorsal view. Abbreviations: A = atrium; BS = blind sac; CD = copulatory duct; CO = copulatory opening; ET = epigynal teeth; FD = fertilization duct; H = hood; PES = posterior epigynal sclerite; S = spermatheca; SE = swollen epigyne; SH = spermathecal head. Scale bar: 0.50 mm.

FIGURE 15. Epigyne and internal genitalia of Baiyuerius shaanensis sp. nov. A epigyne, ventral view B internal genitalia, dorsal view. Abbreviations:A = atrium; CD = copulatory duct; CO = copulatory opening; ET = epigynal teeth; FD = fertilization duct; H = hood; PES = posterior epigynal sclerite; S = spermatheca; SE = swollen epigyne. Scale bar: 0.50 mm.

FIGURE 17. Male palp and right bulb of Baiyueius cuii sp. nov. A–C left palp D, E horizontally flipped right bulb F left embolic tip. A prolateral view B, F ventral view C retrolateral view D dorsal view E apical view. Abbreviations: BL = basal lamellar; C = conductor; CDA = dorsal apophysis of conductor; CDMP = process of dorsal margin 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; TS = tegular sclerite. Scale bars: A–C 0.50 mm, D, E 0.25 mm, F 0.05 mm.

FIGURE 19. Male palp of Baiyueius jiquanyui sp. nov. A–C left palp D, E horizontally flipped right bulb F left embolic tip. A prolateral view B, F ventral view C retrolateral view D dorsal view E apical view. Abbreviations: BL = basal lamellar; C = conductor; CDA = dorsal apophysis of conductor; CDMP = process of dorsal margin of conductor; CF = cymbial furrow; EB = embolic base; Em = embolus; LTA = lateral tibial apophysis; MA = median apophysis; PA = patellar apophysis; PTA = prolateral tibial apophysis; RTA = retrolateral tibial apophysis; ST = subtegulum; T = tegulum; TS = tegular sclerite. Scale bars: A–C 0.50 mm, D–F 0.25 mm, G 0.05 mm.

FIGURE 21. Male palp of Baiyueius digitus sp. nov. A–C left palp D left embolic tip.A prolateral view B, D ventral view C retrolateral view. Abbreviations: C = conductor; CDA = dorsal apophysis of conductor; CF = cymbial furrow; EB = embolic base; Em = embolus; LTA = lateral tibial apophysis; MA = median apophysis; PA = patellar apophysis; RTA = retrolateral tibial apophysis; ST = subtegulum; T = tegulum; TS = tegular sclerite. Scale bars: A–C 0.50 mm, D 0.05 mm.

FIGURE 23. Epigyne and internal genitalia of Baiyuerius shenyunxiaoi sp. nov. A epigyne, ventral view B internal genitalia, dorsal view. Abbreviations: A = atrium; CD = copulatory duct; CO = copulatory opening; FD = fertilization duct; H = hood; S = spermatheca; SE = swollen epigyne; SH = spermathecal head. Scale bar: 0.50 mm.

FIGURE 24. Characters of the female of Baiyuerius shenyunxiaoi sp. nov. A habitus, dorsal view B habitus, prolateral view C eye area, frontal view D eye area, dorsal view E cephalic rigion, lateral view. Scale bars: A, B 3.00 mm, C, D 0.50 mm, E 0.25 mm.

FIGURE 25. Epigyne and internal genitalia of Baiyuerius wenshanensis sp. nov. A epigyne, ventral view B internal genitalia, dorsal view.Abbreviations: A = atrium; AH = anterior hood; CD = copulatory duct; CO = copulatory opening; FD = fertilization duct; H = hood; S = spermatheca; SE = swollen epigyne. Scale bar: 0.50 mm.

FIGURE 27. Male palp of Baiyueius carcharus sp. nov. A–C left palp D, E horizontally flipped right bulb F left embolic tip. A prolateral view B, F ventral view C retrolateral view D retrolateral view E dorsal view. Abbreviations: BL = basal lamellar; C = conductor; CDA = dorsal apophysis of conductor; CDMP = process of dorsal margin of conductor; CF = cymbial furrow; EB = embolic base; Em = embolus; LTA = lateral tibial apophysis; MA = median apophysis; PA = patellar apophysis; RTA = retrolateral tibial apophysis; ST = subtegulum; T = tegulum; TS = tegular sclerite. Scale bars: A–E 0.50 mm, F 0.05 mm.

FIGURE 29. Epigyne and internal genitalia of Baiyuerius carcharus sp. nov. A epigyne, ventral view B internal genitalia, dorsal view. Abbreviations: A = atrium; BS = blind sac; CD = copulatory duct; CO = copulatory opening; FD = fertilization duct; H = hood; PES = posterior epigynal sclerite; S = spermatheca; SE = swollen epigyne; SH = spermathecal head. Scale bar: 0.50 mm.

FIGURE 31. Left male palp of Baiyueius daxi sp. nov. A–C left palp D, E horizontally flipped right bulb F left embolic tip. A prolateral view B, F ventral view C retrolateral view D retrolateral view E dorsal view. Abbreviations: BL = basal lamellar; C = conductor; CDA = dorsal apophysis of conductor; CDMP = process of dorsal margin of conductor; CEBA = ecto-basal apophysis of cymbium; CF = cymbial furrow; CyDA = dorsal apophysis of cymbium; EB = embolic base; Em = embolus; EO = embolic opening; LTA = lateral tibial apophysis; MA = median apophysis; PA = patellar apophysis; RTA = retrolateral tibial apophysis; ST = subtegulum; T = tegulum; TS = tegular sclerite. Scale bars: A–C 0.50 mm, D, E 0.25 mm, F 0.05 mm.

FIGURE 33. Epigyne and internal genitalia of Baiyuerius fengbini sp. nov. A epigyne, ventral view B internal genitalia, dorsal view. Abbreviations: A = atrium; BS = blind sac; CD = copulatory duct; CO = copulatory opening; FD = fertilization duct; H = hood; PES = posterior epigynal sclerite; S = spermatheca; SE = swollen epigyne; SH = spermathecal head. Scale bar: 0.50 mm.