Sidydrassus shumakovi
Creators: name: Fomichev, Alexander A.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Gnaphosidae
Sidydrassus
Sidydrassus shumakovi

description: Sidydrassus shumakovi (Spassky, 1934)
Figs 3–4, 9–10, 25–30, 37–39, 44
Drassus shumakovi Spassky, 1934: 1, pl. 1, figs 1–2 (♂ ♀).
Sidydrassus shumakovi: Esyunin & Tuneva 2002: 177, figs 48–57 (transferred ♂ ♀ from Drassodes).
Sidydrassus shumakovi: Tuneva 2004: 326, figs 41–42 (♂).
Sidydrassus shumakovi: Wunderlich 2011: 37, figs 28–29 (♂ ♀).
For the complete list of references see WSC (2022).
Material examined. KAZAKHSTAN: Almaty Oblast: 1♂ (ISEA, 001.8940), 11 km SSE from Topar Village, Kosshar Natural Boundary, 44°56’N, 75°04’E, sandy semidesert, 360 m, 23– 24.04.2016, A.A. Fomichev; 1♀ (ISEA, 001.8941), 1♀ (ISEA, 001.8942), Malaisary Mt. Range, 44°17’N, 76°52’E, mountain stony steppe with rocks, 550–650 m, 17.04.2016, A.A. Fomichev.
Diagnosis. The male of this species differs from all the congeners in having a prolaterally bent branch of the median apophysis (Lb). In addition, it differs in the proportions of the embolic base (Eb), which is twice thicker than the median apophysis (Ma) in ventral view (vs. equal in its thickness in others species) (cf. Figs 25, 29 and Figs 13, 16, 20, 23, 31, 35). The female of S. shumakovi differs from those of all the congeners in having a slit-shaped epigynal fovea (Fo), not contiguous with the epigastric furrow (vs. wide and round, contiguous with the epigastric furrow in S. tianschanicus and S. rogue) and the posterior receptacles (Pr) with pronounced heads (Rh) (cf. Figs 37–39 and 40–43).
Description. Male. Total length 6.9. Carapace: 3.1 long, 2.15 wide. Colouration. Carapace yellow-brown. Chelicerae, labium and endites light brown. Sternum yellow. Coxae and legs pale yellow. Palps yellow, cymbium light brown.Abdomen and spinnerets yellow-beige. Leg measurements: I: 2.85, 1.4, 2.55, 2.15, 1.5 (10.45). II: 2.55, 1.3, 2.1, 1.9, 1.4 (9.25). III: 2.35, 1.1, 1.75, 1.9, 1.3 (8.4). IV: 3.15, 1.3, 2.55, 3.1, 1.4 (11.5). Leg spination: I: Fe d1-0-1 p0-0-1; Ti v1-2-0; Mt v2-0-0. II: Fe d1-0-1 p0-1-1; Ti v0-1-0; Mt v2-0-0. III: Fe d1-1-1 p0-1-1 r0-1-1; Ti d1-0-0 p1-1-1 r0-1-1 v1-1-2; Mt d1-2-0 p1-1-0 r1-1-0 v2-2-0. IV: Fe d1-1-1 p0-1-1 r0-1-1; Ti d1-0-1 p1-1-1 r1-1-1 v2-2-2; Mt d1-2-0 p1-1-0 r1-1-0 v2-2-0.
Palp as in Figs 25–30. Retrolateral tibial apophysis slightly shorter than tibia. Tegulum (Te) 1.5 times longer than wide. Sperm duct (Sd) clearly visible in ventral view. Median apophysis (Ma) with a robust prolateral branch (Lb). Membrane of median apophysis (Mm) well-developed. Triangular membrane (Tm) between embolus and median apophysis well-developed. Conductor (Cn) originates at a 12 o’clock position. Embolus (Em) slightly longer than median apophysis, bent prolaterad.
Female. Total length 11.0. Carapace: 4.0 long, 2.9 wide. Colouration. Carapace yellow-brown. Chelicerae light brown. Labium, endites and sternum yellow-brown. Coxae yellow. Palps yellow, darker distally. Legs yellow. Abdomen yellow-beige. Spinnerets yellow. Leg measurements: I: 3.05, 1.75, 2.65, 2.25, 1.6 (11.3). II: 3.2, 1.65, 2.5, 2.25, 1.6 (11.2). III: 3.1, 1.4, 2.3, 2.35, 1.55 (10.7). IV: 4.05, 1.65, 3.25, 3.85, 1.8 (14.6). Leg spination: I: Fe d1-0-1 p0-1-1; Ti p1-0-1 v2-0-2; Mt v2-0-0. II: Fe d1-0-1 p0-1-1; Ti p1-0-1 v1-2-0; Mt v2-0-0. III: Fe d1-1-1 p0-1-1 r0-1- 1; Ti d1-0-0 p1-1-1 r1-1-1 v1-2-2; Mt d0-2-0 p1-1-0 r1-1-0 v2-2-0. IV: Fe d1-1-1 p0-1-1 r0-0-1; Ti d1-0-1 p1-1-1 r2-0-1 v2-2-2; Mt d1-2-0 p1-1-0 r1-1-0 v2-0-2.
Epigyne as in Figs 37–39. Fovea (Fo) cross-inclined, with wide lateral margins (Lm). Median plate (Mp) expands anteriorly, rugose. Copulatory openings (Cp) well-visible. Anterior receptacles (Ar) converging, separated by 1.5 times of their diameter. Posterior receptacles (Pr) almost contiguous. Heads of posterior receptacles (Rh) inclined posteriorly.
Distribution. The species has the widest range in the genus. It is known from Azerbaijan throughout the southern part of Russian Plain and the South Urals to southern Kazakhstan, and southward to northern Iran (Esyunin & Tuneva 2002; Huseynov & Nuruyeva 2017; Zamani et al. 2016). The new records from Almaty Oblast represents the easternmost locality of this species (Fig. 44).
Comments. The epigynes of the newly collected females from Almaty Oblast of Kazakhstan differ from those of Iranian and Azeri females, which were illustrated by Zamani et al. (2016) and Huseynov & Nuruyeva (2017), in the following characters: the fovea is almost parallel to the epigastric furrow in Iranian and Azeri females but oblique in the Kazakh females. Yet, the females from Kazakhstan have pronounced heads of the posterior receptacles, which are not visible in Iranian and Azeri females (Zamani et al. 2016; Huseynov & Nuruyeva 2017).
Unfortunately, the females from Malaisary Mt. Range were collected without males to confirm the identification. At present, the above-mentioned differences in the structure of epigyne are treated as a variation, which is normal for the species with such large range. However, it is likely that Iranian and Azerbaijani specimens could belong to a separate, yet undescribed species.
description: Published as part of Fomichev, Alexander A., 2022, A survey of the East Palaearctic Gnaphosidae (Araneae). 12. A review of Sidydrassus Esyunin & Tuneva, 2002, pp. 260-272 in Zootaxa 5194 (2) on pages 267-269, DOI: 10.11646/zootaxa.5194.2.7, http://zenodo.org/record/7147403