Eresus da Lin & Li, 2022

Lin, Yejie, Li, Shuqiang, Zhao, Xin, Chen, Zhanqi & Chen, Haifeng, 2022, Two new Eresus species (Araneae, Eresidae) from Xinjiang, China, Biodiversity Data Journal 10, pp. 94853-94853 : 94853

Eresus da Lin & Li sp. n.

Materials

Type status: Holotype. Occurrence: recordedBy: Xin Zhao; individualID: IZCAS-Ar43547; sex: female; occurrenceID: 9B247645-5769-574E-9924-00D870022C35; Taxon: taxonID: urn:lsid:zoobank.org:act:A52C7C88-A951-4E80-8B28-751DDF692327 ; scientificName: Eresus da Lin & Li, sp. n.; kingdom: Animalia; phylum: Arthropoda; class: Arachnida; order: Araneae; family: Eresidae; genus: Eresus; Location: country: China; stateProvince: Xinjiang Uygur Autonomous Region ; county: Changji Hui Autonomous Prefecture; municipality: Fukang City; locality: Wutonggou National Desert Park ; verbatimElevation: 388 m; decimalLatitude: 44.3920; decimalLongitude: 87.8707; Identification: identifiedBy: Yejie Lin; Event: year: 2022; month: 7; day: 25

Description

Female (Holotype, IZCAS-Ar43547): Habitus as in Fig. 2 A and B. Carapace 10.88 long, 8.62 wide, 8.92 high. Carapace nearly equally wide at pars cephalica and pars thoracica. Carapace red-brown with white setae; pars cephalica elevated. Eye sizes and interdistances: AME 0.21, ALE 0.26, PME 0.51, PLE 0.33, AME-AME 0.37, AME-ALE 3.56, PME-PME 0.65, PME-PLE 2.52, AME-PME 0.11. Pars cephalica with a pointed posterior margin dorsally, almost as long as wide. Chelicerae covered with narrowed white and black setae. Legs with a white ring of setae at joints. Legs with ventral macrosetae on Ta, Mt and Ti I-IV. Leg measurements: I: 17.83 (5.17+5.90+3.94+2.82); II: 16.46 (5.54+5.89+2.94+2.09); III: 14.77 (4.80+5.68+2.63+1.66); IV: 19.53 (6.33+7.29+3.74+2.17). Abdomen dark brown, covered with black setae, with white spots, sigilla conspicuous, surrounded by white setae.

Epigyne (Fig. 3 ) with sclerotised margins, longer than high. Middle plant beyond posterior edge of epigyne margin. Fissure bow-shaped. Copulatory duct translucent, with spermathecal epithelium on anterior edge. Spermathecae distinctly lobed, reaching further laterally than copulatory ducts.

Male. Unknown.

Diagnosis

Females of Eresus da sp. n. are similar to those of E. kollari by a relatively gentle slope of the ocular area (Fig. 2 C and D; Řezáč et al. 2008, fig. 4D; Miller et al. 2012, fig. 2F) and with the epigynal area longer than high (Fig. 3 A; Řezáč et al. 2008, figs. 2A-J). This species can be distinguished from E. kollari by the abdomen with a large number of white spots (Fig. 2 D) (vs. abdomen uniformly black in E. kollari ), the anterior edge of copulatory duct within the anterior edge of epigyne (vs. beyond the anterior edge of epigyne in E. kollari ) and the ventral of fissure curved (vs. almost straight in E. kollari ) (Fig. 4 ).

Etymology

The species name is a noun in apposition derived from the Chinese pinyin “dà” (giant) and refers to the large size of this new species.

Distribution

Known only from the type locality (Xinjiang, China).

Ecology

The spider was found behind a clump of desert plants (Fig. 1 A). The spider habitat is under the ground, with a silk tunnel (around 20 cm in length) connecting its opening and underground nest (Fig. 1 A and B). This underground living strategy may be an adaptive strategy for escaping from the sunlight heating and extremely high temperature of the ground surface. As the silken tunnel was wrapped with dozens of empty beetle exoskeletons (Fig. 1 C and D), we assume that the desert-living beetles are the main diet of the spider, which has a thick fang to pierce the beetles while feeding. In addition, the small size of the spider’s eyes suggest that the spider may adopt a sit-and-wait hunting strategy and that it does not rely on visual signals for hunting.

Figures

Figure 1. Eresus da sp. n. holotype female. A habitat; B microhabitat; C tunnel wrapped with beetle skeleton; D beetle skeleton (Pimeliinae sp.); E spider with nest.

Figure 2. Eresus da sp. n. holotype female (A, B) and E. yukuni sp. n. holotype male (C, D), habitus. A, C dorsal view; B, D lateral view.

Figure 3. Eresus da sp. n. holotype female A epigyne, ventral view; B vulva, dorsal view.

Figure 4. Eresus spp., outlines of copulatory organs (green line, Eresus da sp. n.; red line, E. kollari, changed after Řezac et al. (2008). A epigyne, ventral view; B vulva, dorsal view.