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

publication ID	https://doi.org/10.11646/zootaxa.5636.3.1
publication LSID	lsid:zoobank.org:pub:1A564430-7BA5-4159-A595-3BF3DF2F2D7A
DOI	https://doi.org/10.5281/zenodo.15561573
persistent identifier	https://treatment.plazi.org/id/24487D50-B402-FFCE-9B91-FC8DFA75F852
treatment provided by	Plazi
scientific name	Baiyuerius Zhao, B. Li & S. Li, 2023
status

Treatment

Genus Baiyuerius Zhao, B. Li & S. Li, 2023 View in CoL

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

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 View FIGURE 6 , 10A, B View FIGURE 10 , 24A, B View FIGURE 24 ; 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 View FIGURE 1 ; fig. 317 in Wang et al. 2012); 3) epigyne with large atrium, and copulatory ducts with distinct blind sac ( Fig. 2A–D View FIGURE 2 ; 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 View FIGURE 1 ) [vs. weakly sclerotized in the Yunguirius (fig. 317 in Wang et al. 2012)]; 2) embolic base enlarged ( Fig. 1A–E View FIGURE 1 ) [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 View FIGURE 2 ) [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 View FIGURE 2 ) [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 View FIGURE 21 )............................... digitus- species group Dorsal margin of conductor with modified process.......................................................... 3

3. Patella with two apophyses ( Figs 17C View FIGURE 17 , 19C View FIGURE 19 ).................................................. 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 View FIGURE 27 , 31C, E View FIGURE 31 )........................................................... 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 View FIGURE 1 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 View FIGURE 3 , 5B View FIGURE 5 , 11B View FIGURE 11 ).......................................................................... chongzu -species group

6. Epigynal teeth present ( Figs 9A View FIGURE 9 , 13A View FIGURE 13 , 15A View FIGURE 15 ).............................................. 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 View FIGURE 23 , 25A, B View FIGURE 25 )................................................................................ rotulus -species group Epigynal plate relatively small, width of epigynal pocket obviously longer than length, copulatory ducts short, with blind sacs ( Figs 29A, B View FIGURE 29 , 33A, B View FIGURE 33 )............................................................... zuojiang- species group