Bifidocoelotes mammiformis, Liao & Wang & Yin & Xu, 2022

Liao, Rongrong, Wang, Ziwei, Yin, Haiqiang & Xu, Xiang, 2022, A review of the genus Bifidocoelotes Wang, 2002, with the description of three new species from China (Araneae, Agelenidae), Zootaxa 5222 (2), pp. 179-189 : 183-186

Bifidocoelotes mammiformis sp. nov. (ĀffiȒDĦ)

Figures 4 , 5 , 7

Type material. Holotype male ( HNU604 ), China, Guangdong Province, Shaoguan City, Shixing County, Chebaling National Nature Reserve , 24°42.19'N, 114°09.29'E, 532 m, 3 IX, 2020, Ailan He, Jinxin Liu, Huijuan Sheng, Jia Tang and Yun Liang leg. Paratype ( HNU605 ) : 1 female, with the same data as holotype .

Etymology. The specific epithet is a Latin adjective meaning “having the form of a breast”, referring to the shape of vulva.

Diagnosis. The male of the new species resembles those of B. obscurus Zhou, Yuen & Zhang, 2017 and B. tsoi Li & Blick, 2020 in having a strongly bifid conductor ( Figs 2A, B, D , 4D, E ), but the conductor of the new species has a part shaped like an upright plate in ventral view ( Fig. 4D, E ), which is lacking in the other two species. The female of the new species is similar to those of B. primus ( Fox, 1937) , B. quadratus sp. nov., and B. tsoi Li & Blick, 2020 in having a strongly bifurcated epigynal tooth ( Figs 1B–D, F , 5C , 6C ), but it can be distinguished by the different shape of spermathecae, which is globular in the new species ( Fig. 5D ), but longitudinally extending in Bifidocoelotes tsoi Li & Blick, 2020 ( Wang et al. 2001: fig. 2), and more or less transversely extending in B. primus ( Fox, 1937) ( Zhou et al. 2017: figs 3B, 4D) and B. quadratus sp. nov. ( Fig. 6D ).

Description. Male: Total length 7.59, carapace 3.89 long, 2.52 wide, abdomen 3.43 long, 2.25 wide. Carapace pyriform, almost completely dark except for bright yellow center of head region and lateral margins of thoracic region. Fovea brown, long, linear. Eye sizes and interdistances: AME 0.11, ALE 0.16, PME 0.17, PLE 0.15, AME– AME 0.06, AME–ALE 0.05, PME–PME 0.12, PME–PLE 0.12, ALE–PLE 0.04, AME–PME 0.13, ALE–ALE 0.67, PLE–PLE 0.86. MOA 0.42 long, anterior width 0.26, posterior width 0.41. Clypeus height 0.10. Leg measurements: I 12.6 (3.10, 1.16, 2.87, 3.29, 2.18); II 10.4 (2.88, 1.13, 2.05, 2.67, 1.67); III 9.68 (2.42, 1.18, 1.91, 2.88, 1.29); IV 12.81 (3.07, 1.25, 2.98, 4.06, 1.45); leg formula IV, I, II, III. Abdomen oval, dorsum black, with four brown chevrons and numerous brown patches ( Fig. 4A ); ventral side grey, with irregularly scattered black dots. Spinnerets yellowish ( Fig. 4B ).

Palp ( Fig. 4C–E ): Cymbial furrow (CF) extremely long, almost reaching distal end of cymbium, and with dorsal edge strongly concave. Patellar apophysis (PA) strong, finger-like in retrolateral view. Retrolateral tibial apophysis (RTA) wide, with a somewhat rounded distal end, extending slightly beyond distal end of tibia. Lateral tibial apophysis (LTA) small. Embolus (Em) very long and slender, originating at approximately six o’clock position. Conductor (Co) strong and slightly spiral, with a strongly bifid end and with a part shaped like an upright rounded dish in ventral view. Conductor lamella (CL) well developed, broad, membranous. Median apophysis (MA) relatively small and spoon-like.

Female: Total length 8.31, carapace 3.64 long, 2.14 wide, abdomen 4.41 long, 3.28 wide. Eye sizes and interdistances: AME 0.08, ALE 0.13, PME 0.14, PLE 0.11, AME–AME 0.05, AME–ALE 0.07, PME–PME 0.09, PME–PLE 0.10, ALE–PLE 0.07, AME–PME 0.12, ALE–ALE 0.61, PLE–PLE 0.81. MOA 0.38 long, anterior width 0.27, posterior width 0.40. Clypeus height 0.13. Chelicerae yellow-brown. Endite brown, longer than wide. Labium brown. Sternum yellow-brown, with sparse brown setae. Legs yellow-brown, with black annulations and some spines. Leg measurements: I 7.97 (2.21, 1.05, 1.73, 1.81, 1.17); II 7.54 (2.13, 0.93, 1.42, 1.99, 1.07); III 7.29 (2.06, 0.80, 1.70, 1.69, 1.04); IV 9.42 (2.61, 0.79, 2.02, 2.78, 1.22); leg formula IV, I, II, III. Other characteristics as in male.

Epigyne ( Fig. 5C, D ): Epigynal tooth (ET) long, bifurcation less than one half of its total length, originating from antero-mesal portion of epigyne. Copulatory openings (CO) small, located on both sides of ET. Copulatory ducts (CD) long, strongly convoluted, situated between spermathecae. Spermathecae situated close to each other. Spermathecal heads (SH) small, mammiform, located anteriorly. Fertilization ducts (FD) short, membranous, distant from each other, originating from posterior margins of spermathecae.

Distribution. Known only from the type locality in China (Guangdong) ( Fig. 7 ).

Figures

FIGURE 1. The epigynes of six Bifidocoelotes spp., ventral view. A. Bifidocoelotes obscurus (after Zhou et al. 2017); B. Bifidocoelotes primus (after Zhou et al. 2017); C. Bifidocoelotes tsoi (after Wang et al. 2001); D. Bifidocoelotes mammiformis sp. nov.; E. Bifidocoelotes elongatus sp. nov.; F. Bifidocoelotes quadratus sp. nov.. Scale bar: 0.3 mm.

FIGURE 2. The distal parts of conductors of four Bifidocoelotes spp., ventral view.A. Bifidocoelotes mammiformis sp. nov.; B. Bifidocoelotes tsoi (after Wang et al. 2001); C. Bifidocoelotes primus (after Zhou et al. 2017); D. Bifidocoelotes obscurus (after Zhou et al. 2017). Scale bars: A, B, D = 0.1 mm; C = 0.05 mm.

FIGURE 4. Bifidocoelotes mammiformis sp. nov., holotype male. A. Habitus, dorsal view; B. Same, ventral view; C. Left palp, prolateral view; D. Same, ventral view; E. Same, retrolateral view. Abbreviations: CF, cymbial furrow; CL, conductor lamella; Co, conductor; Em, embolus; LTA, lateral tibial apophysis; MA, median apophysis; PA, patellar apophysis; RTA, retrolateral tibial apophysis. Scale bars: A, B = 1 mm; C–E = 0.3 mm.

FIGURE 5. Bifidocoelotes mammiformis sp. nov., paratype female.A. Habitus, dorsal view; B. Same, ventral view; C. Epigyne, ventral view; D. Same, dorsal view. Abbreviations: CD, copulatory duct; CO, copulatory opening; ET, epigynal tooth; FD, fertilization duct; SH, spermathecal head; Sp, spermatheca. Scale bars: A, B = 1 mm; C, D = 0.2 mm.

FIGURE 6. Bifidocoelotes quadratus sp. nov., holotype female. A. Habitus, dorsal view; B. Same, ventral view; C. Epigyne, ventral view; D. Same, dorsal view. Abbreviations: At, atrium; CD, copulatory duct; ET, epigynal tooth; FD, fertilization duct; SH, spermathecal head; Sp, spermatheca. Scale bars: A, B = 1 mm; C, D = 0.1 mm.

FIGURE 7. Collection localities for Bifidocoelotes in China. 1. B. mammiformis sp. nov.; 2. B. elongatus sp. nov.; 3. B. quadratus sp. nov.; 4. B. tsoi; 5. B. obscurus; 6. B. primus.