Scutacarus moseri Khaustov, 2015, sp. nov.

Scutacarus moseri sp. nov.

(Figs. 1–4)

Description. FEMALE. Length of idiosoma 160 (155–170), width 175 (150–175). Gnathosoma (Figs. 2 A, B): gnathosomal capsule oval, with well-developed dorsal median apodeme, dorsally with 2 pairs of sparsely barbed and pointed setae (cha, chb) and 1 pair of postpalpal setae (pp), situated anterolaterally to bases of setae cha (Fig. 2 A); setae chb slightly longer than cha. Palps dorsolaterally with setae dFe and dGe; dGe slightly longer than dFe. Palps ventrally with large mushroom-like accessory setigenous structure (ass). Palpal solenidion absent. Palptarsus with tiny seta-like process. Palps terminated with small tibial claw. Gnathosomal venter with 1 pair of pointed subcapitular setae m and pair of round pits situated posteriorly to bases of setae m (Fig. 2 B). Gnathosomal capsule without rough microsculpture. All pharyngeal pumps transversely striated. Pharyngeal pump 1 oval, separated from pharyngeal pump 2 by 2 lengths of pharyngeal pump 1, pharyngeal pump 2 distinctly larger than pump 1, oval, pharyngeal pump 3 oval, subequal to pharyngeal pump 1(Fig. 2 A). Idiosomal dorsum (Figs. 1 A, 2C). 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. 2 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 and h 1 distally thickened and strongly barbed; setae f not thickened, long, blunt-ended and distinctly barbed; setae e and h 2 curved, sparsely barbed and pointed. Cupules ia on tergite D and ih on tergite H large, round. Pair of small pore-like structures situated posteromedially to setae c 1. 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 30 (26 – 31), c 2 27 (23 – 27), d 30 (27– 31), e 33 (29–33), f 64 (51–65), h 1 28 (23–28), h 2 36 (30–36). Distances between setae: c 1– c 1 65 (55–66), d–d 115 (88–115), f–f 76 (53–76), h 1– h 1 43 (34–44). Idiosomal venter (Fig. 1 B): All ventral plates with numerous small dimples. Apodemes 1 (ap1) well developed and joined with prosternal apodeme (appr), apodemes 2 (ap2) ushaped, joined with appr; sejugal apodeme (apsej) well developed and joined with appr. Secondary transverse apodeme (sta) present. Apodemes 3 absent, apodemes 4 (ap4) short, joined with poststernal apodeme (appo). Apodemes 5 indistinct. Setae 2 b distinctly thickened, smooth, blunt-ended, setae 4 a smooth, with thickened base, situated distinctly anteriorly to 4 b, setae ps 1-2 subequal, blunt-ended, distinctly barbed on one side; setae ps 3 short and smooth. Other ventral setae distinctly barbed. Bases of setae of poststernal plate covered by short cuticular outgrowths. Anterior genital sclerite (ags) bell-like, posterior genital sclerite (pgs) large, triangular. Lengths of ventral setae: 1 a 29 (24–30), 1 b 23 (22–25), 2 a 19 (17–20), 2 b 13 (10–13), 3 a 26 (23–26), 3 b 27 (24–28), 3 c 32 (26–32), 4 a 15 (12–15), 4 b 61 (47–63), 4 c 34 (31–35), ps 1 26 (26–29), ps 2 26 (26–29), ps 3 14 (12–14). Legs (Figs. 3, 4). Leg I (Fig. 3 A). Leg setation: Tr-1, Fe-3, Ge-4, TiTa-16(4). Tibiotarsus with large tarsal claw, tapering on its end. Seta k blunt-ended, with several weak barbs, eupathidion tc” situated on long pinnaculum; tc’ on short protuberance. Lengths of solenidia: ω 1 9 (8–9)> ω 2 5 (4–5) <φ 1 7 (6–7)> φ 2 5 (4–5); ω 2 and φ 2 baculiform, φ 1 clavate, ω 1 finger-shaped. Seta dFe thickened and pointed. Seta l’ of femur blunt-ended and smooth. Leg II (Fig. 3 B). Leg setation: Tr-1, Fe-3, Ge-3, Ti-4(1), Ta-6(1). Tarsus with large padded claws and well-developed flipperlike empodium. Solenidion ω 8 (6–8) finger-shaped, solenidion φ 4 (3–4) weakly clavate. Seta l’ of femur short, smooth, pointed; v” of femur short, spine-like. Seta pl” spine-like, with several short barbs, u’ blunt-ended and barbed in distal half. Leg III (Fig. 4 A). Leg setation: Tr-1, Fe-2, Ge-2, Ti-4(1), Ta-6. Claws of same shape as on tarsus II. Solenidion φ 4 (3–4) weakly clavate. Setae pl” spine-like, weakly barbed, u’ blunt-ended and barbed in distal half. Leg IV (Fig. 4 B). Leg setation: Tr-1, Fe-2, Ge-1, TiTa-6. Setae d of femur, d and tc’ of tibiotarsus bluntended. Tibiotarsus shorter than its width. Seta tc” absent. Trochanter ventrodistally with spine-like process.

MALE and LARVA unknown.

Type material. Female holotype (slide AK 240815) and 29 paratypes, RUSSIA, Tyumen Province, Tyumen District, vicinity of Tyumen, 57°09'50.4"N, 65°27'26.7"E, in nest of Lasius flavus, 24 August 2015, coll. A.A. Khaustov;

Type deposition. Holotype and 31 paratypes deposited in TUMZ; 2 paratypes in ZISP.

Non-type material. 4 females, RUSSIA, Crimea, Dolgorukov mountain pasture, 44°50'01.1"N, 34°23'19.1"E, on ants Lasius flavus, 9 August 2015, coll. A.A. Khaustov.

Etymology. The new species is named after the well-known U.S.A. acarologist and entomologist, Dr. John Moser, who passed away in 2015, to honor his remarkable contributions to knowledge of myrmecophilous mites.

Differential diagnosis. Female of this new species is most similar to S. velutinosus Sevastianov, 1983 by the presence of distally thickened and strongly barbed setae c 1, c 2 and d, the presence of six setae on tibiotarsus IV and by the presence of the secondary transverse apodeme. It differs from S. velutinosus by setae h 1 thickened distally and strongly barbed and similar to c 1, c 2 and d (vs. h 1 short, not thickened and slightly barbed, not similar to c 1, c 2 and d in S. velutinosus) and by thickened basally setae 4 a (vs. not thickened).