Scutacarus heterotrichus sp. nov. (Figs. 9–12) Description. FEMALE. Length of idiosoma 200 (145–200), width 175 (135–185). Gnathosoma (Figs. 10 A, B): in general similar to that of S. moseri sp. nov. except for presence of tiny palpal solenidion just laterad to accessory setigenous structure. Idiosomal dorsum (Fig. 9 A, 10C). Prodorsum completely covered by tergite C, with 2 pairs of smooth needle-like setae v 2 and sc 2, 1 pair of barbed capitate trichobothria (Fig. 10 C) and 1 pair of oval stigmata associated with long tracheal trunks. Lateral propodosomal spine absent. All dorsal shields with numerous small dimples. Setae c 1, c 2, d, f and h 1 short, blunt-ended and sparsely barbed; setae e and h 2 long, curved, sparsely barbed and tapered at its end. Cupules ia on tergite D and ih on tergite H relatively small and round. Tergites EF and H each with 1 pair of oval porous fields situated anteromedially to setae f and anteriorly to setae h 1. Lengths of dorsal setae: c 1 17 (16 – 18), c 2 17 (15 – 17), d 11 (9–12), e 43 (32–44), f 11 (10–12), h 1 10 (8–10), h 2 40 (31–40). Distances between setae: c 1– c 1 46 (40–48), d–d 77 (70–78), f–f 65 (60–69), h 1– h 1 30 (26–30). Idiosomal venter (Fig. 9 B). All ventral plates with numerous small dimples. Ap1 well-developed and joined with appr, ap2 thin, u-shaped and joined with appr; apsej well developed and joined with appr. Sta present. Apodemes 3 absent, ap4 short and joined with appo. Apodemes 5 joined with appo and diffuse. Setae 2 b slightly thickened, smooth, blunt-ended, setae 4 a smooth, pointed, situated at same level as 4 b, setae ps 3 short and smooth. Other ventral setae sparsely barbed. Ags tongue-like, pgs large, triangular. Lengths of ventral setae: 1 a 27 (23–27), 1 b 23 (17–23), 2 a 20 (14–20), 2 b 19 (16–19), 3 a 18 (15–19), 3 b 18 (17–21), 3 c 52 (42–52), 4 a 15 (11–15), 4 b 60 (49–60), 4 c 57 (46–57), ps 1 16 (14– 16), ps 2 16 (14–16), ps 3 7 (5–7). Legs (Figs. 11, 12). Leg setation as in S. moseri sp. nov. except presence of 7 setae on tibiotarsus IV (tc” present). Leg I (Fig. 11 A). Tibiotarsus with large tarsal claw, tapered at the end. Seta k long, pointed and sparsely barbed, eupathidion tc” situated on long pinnaculum; tc’ on short protuberance. Lengths of solenidia: ω 1 9 (8–9)> ω 2 3 (3) φ 2 5 (4–5); ω 2 and φ 2 weakly clavate, φ 1 clavate, ω 1 finger-shaped. Seta dFe thickened, spine-like, sparsely barbed. Seta l’ of femur smooth, blunt-ended. Leg II (Fig. 11 B). Tarsus with large padded claws and well-developed flipper-like empodium. Solenidion ω 10 (9–10) finger-shaped, solenidion φ 5 (4–5) weakly clavate. Seta l’ of femur short, smooth and pointed; v” of femur short, spine-like. Seta pl” spine-like, smooth, u’ blunt-ended and barbed in distal half. Leg III (Fig. 12 A). Claws of same shape as on tarsus II. Solenidion φ 5 (4–5) weakly clavate. Setae pl” spine-like, smooth, u’ blunt-ended and barbed in distal half. Leg IV (Fig. 12 B). Setae d of femur and tc” of tibiotarsus blunt-ended. Tibiotarsus about 1.5 times longer than its width. Setae tc’ distinctly thicker than other setae of tibiotarsus. MALE and LARVA unknown. Type material. Female holotype (slide AK 150515) and 6 female paratypes, RUSSIA, Tyumen Province, vicinity of lake Kuchak, 57°20'13.9"N, 66°03'30.4"E, on ants and in nest of Lasius flavus, 15 May 2015, coll. A.A. Khaustov. Type deposition. Holotype and 4 paratypes deposited in TUMZ; 2 paratypes in ZISP. Etymology. The name of this new species derived from Greek words δεύτερος meaning “different” and τρίχα meaning “hair” and refers to the presence of the idiosomal setae of considerably different shape and length. Differential diagnosis. Female of this species is similar to S. ghosali Mahunka, 1971, described from India (Mahunka 1971a), by the similar relative length and shape of the dorsal idiosomal setae. It differs from S. ghosali by subequal and distinctly barbed setae ps 1-2 (vs. ps 1 much longer than ps 2 and both smooth in S. ghosali) and by much shorter setae ps 3, which are about two times shorter than ps 1-2 (vs. longer than ps 1-2).

Published as part of Khaustov, Alexander A., 2015, Myrmecophilous pygmephoroid mites (Acari: Pygmephoroidea) associated with Lasius flavus (Hymenoptera: Formicidae) in Russia, pp. 345-370 in Zootaxa 4044 (3) on pages 354-356, DOI: 10.11646/zootaxa.4044.3.2, http://zenodo.org/record/231968