Acantholycosa sidorovi Fomichev 2021, sp. n.

Acantholycosa sidorovi sp. n.

Figs 16–17, 24–27, 34–35, 60–62, 75–76

Types. RUSSIA: Altai Krai: holotype ♂ (ISEA, 001.8653), Tigirek Mt. Range, without precise locality and date, collector unknown (donated by V. V. Sidorov); paratypes: 1♂ (ISEA, 001.8654), 1♀ (ISEA, 001.8724), together with the holotype; 2♂ 1♀ (ISEA, 001.8655), Tigirek Mt. Range, the upper reaches of Babii Klyuch River, 51°03’N, 82°58’E, 1400–1500 m, 9.07.2016, collector unknown (donated by V. V. Sidorov).

Etymology. The specific name is a patronym given in honor of my friend, Vladislav V. Sidorov (Barnaul, Russia), who donated the types of the new species.

Diagnosis. The new species is closely related to A. altaiensis, which is also known from the Western Altai. Both species have a spine (Sp) near base of the embolus (Em), laminar apical arm (Aa) of the tegular apophysis (Tg) and diamond-shaped epigynal fovea (Fo) with pentagonal septal base (Sb). The male of A. sidorovi sp. n. differs by the enlarged and more curved paleal outgrowth (Po), more prominent spine near base of the embolus (in retrolateral view) and by underdeveloped apical arm of the tegular apophysis (cf. Figs 25, 27, 34 and figs 2, 4, 6 in Marusik et al. 2004). The female of the new species can be separated from the female of A. altaiensis by the apical pocket (Ap) almost as wide as the epigynal fovea (vs. significantly narrower) and by the longer and thinner receptacles (Re, cf. Figs 60, 62 and figs 8–9 in Marusik et al. 2004).

Description. Male (holotype). Total length 7.5. Carapace: 3.8 long, 3.2 wide. Coloration. Carapace dark brown. Eye field almost black. Chelicerae, sternum and palps brown. Labium, endites and coxae yellow-gray. Legs yellowbrown. Femora of legs with brown transverse stripes and longitudinal yellow stripes. Abdomen yellow-brown dorsally. Cardiac mark almost indistinct. Venter of the abdomen yellow-gray. Spinnerets dark gray. Spination of leg I: Fe d1-1-1 p0-0-2 r0-1-1; Ti p1-0-0 r1-0-0 v2-2-2-2-1-2; Mt p1-1-0 r0-1-0 v2-2-0. Leg measurements: I 4.4, 1.7, 4.2, 4.6, 1.8 (16.7); II 4.3, 1.7, 4.0, 4.7, 1.85 (16.55); III 4.2, 1.55, 3.6, 5.45, 1.85 (16.65); IV 4.9, 1.6, 4.3, 6.3, 1.55 (18.65).

Palp as in Figs 16–17, 24–27, 34–35. Tegular apophysis almost square, with a poorly developed basal arm (Ba). Palea (Pl) rounded. Paleal outgrowth strongly bent. Terminal apophysis (Ta) straight, spine-like. Embolus with a semicircular notch in the distal part.

Female. Total length 8.7. Carapace: 3.4 long, 2.75 wide. Coloration. Carapace dark brown. Eye field almost black. Chelicerae, sternum and labium brown. Endites and coxae yellow-gray. Legs and palps yellow-gray with brown annulation. Abdomen brown-gray dorsally. Cardiac mark dark brown. Venter of the abdomen yellow. Spinnerets yellow-gray. Spination of leg I: Fe d1-1-1 p0-0-2 r0-0-1; Ti p1-0-0 r1-0-0 v2-2-2-2-1-2; Mt p0-1-0 r0- 1-0 v2-2-0. Leg measurements: I 3.15, 1.45, 2.8, 2.75, 1.35 (11.5); II 3.15, 1.4, 2.65, 2.85, 1.3 (11.35); III 2.9, 1.25, 2.45, 3.45, 1.4 (11.45); IV 3.75, 1.4, 3.25, 5.15, 1.95 (15.5).

Epigyne and internal genitalia as in Figs 60–62. Fovea slightly longer than wide. Septal base smooth, 2 times longer than wide. Septal stem undeveloped. Lips of the epigyne (Li) not touching each other. Apical pocket with one hood. Receptacles fusiform. Copulatory ducts (Cd) almost straight, as long as receptacles.

Distribution. Known only from the type locality in the Altai Mountains (Figs 75–76).