Holostaspis isotricha Kolenati

Figures 38–42.

Holostaspis isotricha Kolenati, 1858: 87 .

Holostaspis isotricha .— Oudemans, 1914: 68 (in part); Vitzthum, 1929: 26; Bregetova, 1977: 549; Keum et al., 2017: 490; Babaeian et al., 2019.

Hypoaspis (Holostaspis) isotricha .— Evans & Till, 1966: 203; Karg, 1982: 248; 1993: 157.

Specimens examined. Six females, RUSSIA, Tyumen Province, vicinity of lake Kuchak, 57°21’N, 66°03’E, 27 April 2018, O. Joharchi coll., in the nest of F. rufa L. ( Hymenoptera: Formicidae); three females, Tyumen Province, vicinity of Uspenka, 57°04’N, 65°04’E, 21 May 2018, O. Joharchi coll., in the nest of F. fusca L. ( Hymenoptera: Formicidae) in the rotting stems of trees; ten females, Tyumen Province, vicinity of lake Kuchak, 57°21’N, 66°03’E, 16 June 2016, A.A. Khaustov coll., in the nest of Formica polyctena Förster and F. rufa L. ( Hymenoptera: Formicidae).

Notes. Holostaspis isotricha was described from Brno, Czech Republic (Kolenati, 1858) where it was found from nests of Formica rufa L. ( Hymenoptera: Formicidae). Vitzthum (1929) synonymised H. isotricha and H. oophila (Wasmann, 1897), but did not provide any explanation for that decision, and did not give details of the specimens he examined. We followed here Evans & Till (1966), and consider them as separate species. Our concept of the species is based on that of Evans & Till (1966), and our specimens agree completely with Evans & Till (1966, Fig. 36) and Babaeian et al. (2019, Figs 33–43). This species very widely distributed in Europe and Russia in ants’ nests (Evans & Till, 1966; Bregetova, 1977; Karg, 1982; Babaeian et al., 2019), and it is now recorded in Western Siberia for the first time, from the same host. The species is easily recognised by thick, long dorsal setae, almost all setae with 2–4 minute barbs distally and reaching base of next posterior setae (Fig. 38), epistome smooth (Fig. 41), anal shield with anterolateral extension, post-anal seta long and thick (Fig. 39), ad1 on femur I-IV well thickened and fixed digit of chelicera with a small tooth distaly and movable digit with terminal hook (Fig. 42).