Dasythyreus polytrichus Khaustov and Abramov 2010
Creators: name: Khaustov, Alexander A.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Trombidiformes
Dasythyreidae
Dasythyreus
Dasythyreus polytrichus

description: Dasythyreus polytrichus Khaustov and Abramov, 2010
(Figs 1–17)
Dasythyreus polytrichus Khaustov and Abramov, 2010, p. 266, Figs 1–8
Description. LARVA (Figs 1–3, 16, 17A). Length of body 255–260, length of idiosoma 205, width 180–190.
Idiosomal dorsum (Figs 1A, 16 A–C). Body almost round, soft, striated, with weakly defined prodorsal and hysterosomal plates of segments C, D, E, F, and H delineated by more thin stria than interscutal cuticle (Fig. 16B). All dorsal setae located on short protuberances. Prodorsum with three pairs of setae ve, sci, sce and one pair of round eyes anteriad setae sce. Segments C and D with four pairs of setae each; segments E and F with three pairs of setae each; segment H with two pairs of setae. Setae vi, ve, c 1, c 3, c 4, e 2, e 3, f 2, and f 3 with attenuate thin tips, other dorsal setae with rounded tips. Short transverse row of small round dimples situated between gnathosoma and anterior margin of prodorsal plate.
Idiosomal venter (Figs 1B, 16D, E). Ventral idiosoma striated; coxal fields I–III delineated by more thin stria than interscutal cuticle; two pairs of intercoxal setae 1 a and 3 a; one pair of setae 1 b on coxal fields I; pseudanal segment long, conical, with two pairs of pseudanal setae ps 1, 2; one pair of cupules ih located anterolaterad pseudanal segment (Fig. 16E). All ventral setae thin, pointed, smooth, except weakly barbed 1 b.
Gnathosoma (Figs 2, 16F). Length of gnathosoma 50–51, width 68–70. Stylophore weakly striated, attenuated distally, with 6-segmented peritremes; palpal supracoxal seta ep weakly clavate. Palps 5-segmented; palp setation: Tr 0, Fe 1 (d), Ge 1 (d), Ti 3 (d, l’, l”), Ta 6(1) (va, ba, bp, sul, ul’ξ, ul”ξ, ω); setae (ul) blunt-ended, eupathid-like,, other palpal setae pointed; seta d of femur distinctly barbed; setae d of genu and va with few barbs; other palpal setae smooth; solenidion ω weakly clavate; tibial claw long, straight, narrow and with distinctly rounded tip. Subcapitulum weakly striated, with two pairs of smooth, blunt-ended adoral setae (or 1, 2), distally with sucker-like lips (Fig. 16F).
Legs (Figs 3, 17A). Lengths of legs: I 145–155, II 120–130, III 115–120. All tarsi with long and thin pretarsi, pair of small claws with several short dorsomedian projections in basal half, and elongate empodium with numerous capitate chaetoids. Leg I (Figs 3A, 17A). Leg setation: Tr 0, Fe 2 (d, bv”), Ge 2 (d, k), Ti 4(1) (d, l”, v’, v”, φ), Ta 9(1) (tc’ξ, tc”, p’, p”ξ, a’, a”, pl’, u’, u”, ω); setae p” and tc’ eupathid-like, blunt-ended, p” smooth, tc’ weakly barbed in basal half; seta p’ blunt-ended and barbed; seta k clavate; seta d of femur blunt-ended and strongly barbed; other leg setae pointed and barbed; solenidia uniformly thin; lengths of solenidia: ω 11–12, φ 92–94; leg supracoxal seta (el) clavate. Leg II (Fig. 3B). Leg setation: Tr 0, Fe 2 (d, bv”), Ge 1 (k), Ti 4 (d, l”, v’, v”), Ta 8(1) (tc’, tc”, p’ ξ, p”ξ, a’, a”, u’, u”, ω); setae (p) eupathid-like, smooth, blunt-ended; seta a’ weakly blunt-ended, barbed; setae d of femur and tibia strongly and densely barbed, with rounded tips; other leg setae pointed and barbed; seta k slightly thickened distally; solenidion ω (14–17) uniformly thin. Leg III (Fig. 3C). Leg setation: Tr 0, Fe 1 (d), Ge 0, Ti 4 (d, l”, v’, v”), Ta 6 (tc’, tc”, a’, a”, u’, u”); seta a’ weakly blunt-ended, barbed; setae d of femur and tibia strongly and densely barbed, with rounded tips; other leg setae pointed and barbed.
PROTONYMPH (Figs 4–7, 17 B–F). Length of body 315–325, length of idiosoma 250–270, width 215–230.
Idiosomal dorsum (Figs 4A, 15A, 17 B–D). In general similar to larva, but with more dorsal setae (polytrichy). Idiosoma dorsally with 35 pairs of setae: seven pairs of prodorsal, eight pairs on segment C, seven pairs on segment D, six pairs on segment E, five pairs on segment F, and two pairs on segment H. One pair of median setae on segments D, E, and F with very long and strong lateral projections (Fig. 17D); 17 pairs of setae with attenuate tip, other dorsal setae with rounded tips. Short transverse row of small round dimples situated between gnathosoma and anterior margin of prodorsal plate.
Idiosomal venter (Figs 4B, 17E). In general similar to larva, but setae 1 c, 2 c, 3 c and ag 1 added. All ventral setae thin and pointed; setae 1 a, 1 b, and ag 1 weakly barbed, other ventral setae smooth.
Gnathosoma (Fig. 5). Length of gnathosoma 54–64, width 80–81. Stylophore as in larva, but with 9-10-segmented peritremes. Palps as in larva, except presence of seta v” on femur and tarsal seta sul eupathid-like and bluntended. Subcapitulum as in larva, except presence of weakly barbed and pointed setae m.
Legs (Figs 6, 7, 17F). Lengths of legs: I 190–195, II 150–155, III 145–150, IV 125–130. Leg I (Fig. 6A). Leg setation: Tr 1 (v’ N 1), Fe 2 (d, bv”), Ge 2 (d, k), Ti 5(1) (d, l’ N 1, l”, v’, v”, φ), Ta 10(1) (tc’ξ, tc” ξ, p’ ξ, p”ξ, a’, a”, pl’, u’, u”, pv” N 1, ω); lengths of solenidia: ω 15–17, φ 98–110. Setae tc” and p’ eupathid like; setae v” of trochanter, l’ of tibia, and pv” of tarsus barbed and pointed; other setae as in larva. Leg II (Fig. 6B). Leg setation: Tr 1 (v’ N 1), Fe 2 (d, bv”), Ge 1 (k), Ti 5 (d, l’ N 1, l”, v’, v”), Ta 9(1) (tc’, tc”, p’ ξ, p”ξ, a’, a”, u’, u”, pv” N 1, ω); solenidion ω 18–21; setae v” of trochanter, l’ of tibia, and pv” of tarsus barbed and pointed; other setae as in larva. Leg III (Fig. 7A). Leg setation: Tr 1 (v’ N 1), Fe 1 (d), Ge 0, Ti 4 (d, l”, v’, v”), Ta 7 (tc’, tc”, a’, a”, u’, u”, pv” N 1); setae v” of trochanter and pv” of tarsus barbed and pointed; other setae as in larva. Leg IV (Figs 7B, 17F). Leg setation: Tr 0, Fe 1 (d N 1), Ge 0, Ti 4 (d N 1, l” N 1, v’ N 1, v” N 1), Ta 6 (tc’ N 1, tc” N 1, a’ N 1, a” N 1, u’ N 1, u” N 1); seta a’ weakly bluntended, barbed; setae d of femur and tibia strongly and densely barbed, with rounded tips; other leg setae pointed and barbed.
DEUTONYMPH (Figs 8–10, 15A). Length of body 465–515, length of idiosoma 395–440, width 300–325.
Idiosomal dorsum (Fig. 8A). In general similar to protonymph, but with more dorsal setae Idiosoma dorsally with 54 pairs and two unpaired setae: 25 pairs and one unpaired of prodorsal and segment C, 12 pairs and one unpaired on segment D, nine pairs on segment E, six pairs on segment F, and two pairs on segment H. One pair of median setae on segments D, E, and F with very long and strong lateral projections; 15 pairs of setae with long attenuate tip, other dorsal setae with rounded tips. Short transverse row of small round dimples situated between gnathosoma and anterior margin of prodorsal plate (Fig. 15A).
Idiosomal venter (Fig. 8B). In general similar to protonymph, but setae 2 b, 3 b, 4 c, ag 2 and g 1 added. All ventral setae thin and pointed; setae 1 a, 2 b, 3 b distinctly barbed; 1 c, 2 c, 3 a, 3 c, and 4 c smooth, other ventral setae with few weak barbs.
Gnathosoma as in protonymph.
Legs (Figs 9, 10). Lengths of legs: I 270–275, II 210–235, III 205–220, IV 190–215. Leg I (Fig. 9A). Leg setation: Tr 1 (v’ N 1), Fe 2 (d, bv”), Ge 2 (d, k), Ti 5(1) (d, l’ N 1, l”, v’, v”, φ), Ta 11(1) (tc’ξ, tc” ξ, p’ ξ, p”ξ, a’, a”, pl’ξ, u’, u”, pv’ N 2, pv” N 1, ω); lengths of solenidia: ω 18–19, φ 110–130. Seta pl’ eupathid like; seta a’ blunt-ended, similar to a”; seta pv’ of tarsus barbed and pointed; other setae as in protonymph. Leg II (Fig. 9B). Leg setation: Tr 1 (v’ N 1), Fe 2 (d, bv”), Ge 1 (k), Ti 5 (d, l’ N 1, l”, v’, v”), Ta 10(1) (tc’, tc”, p’ ξ, p”ξ, a’, a”, u’, u”, pv’ N 2, pv” N 1, ω); solenidion ω 26–29; both setae (a) similar in shape, blunt-ended and barbed; seta pv’ of tarsus barbed and pointed; other setae as in protonymph. Leg III (Fig. 10A). Leg setation: Tr 1 (v’ N 1), Fe 1 (d), Ge 0, Ti 4 (d, l”, v’, v”), Ta 8 (tc’, tc”, a’, a”, u’, u”, pv’ N 2, pv” N 1); both setae (a) similar in shape, blunt-ended and barbed; seta pv’ of tarsus barbed and pointed; other setae as in protonymph. Leg IV (Fig. 10B). Leg setation: Tr 1 (v’ N 2), Fe 1 (d N 1), Ge 0, Ti 4 (d N 1, l” N 1, v’ N 1, v” N 1), Ta 8 (tc’ N 1, tc” N 1, a’ N 1, a” N 1, u’ N 1, u” N 1, pv’ N 2, pv” N 2); both setae (a) similar in shape, blunt-ended and barbed; setae (pv) of tarsus barbed and pointed; other setae as in protonymph.
MALE (Figs 11–14, 15B). Length of body 450–575, length of idiosoma 365–465, width 310–390.
Idiosomal dorsum (Fig. 11C). Number and shape of dorsal idiosomal setae as described in female (see Khaustov & Abramov 2010), except area near anal opening with two pairs of simple and smooth pseudanal setae. No dimples between gnathosoma and anterior margin of prodorsal plate.
Idiosomal venter (Fig. 11A). In general similar to deutonymph, but seta 4 b added. All ventral setae thin and pointed; setae 1 b, 2 b, 3 b, 4 b distinctly barbed; other setae as in deutonymph. Coxal fields I and II fused medially forming prosternal apodeme (appr) fused with apodemes 1 (ap1); apodemes 2 (ap2) well developed; apodemes 3, 4, and 5 (ap3–5) well developed and fused together medially. Aedeagus long, retractable (Figs 11B, C).
Gnathosoma (Figs 12, 15B). Length of gnathosoma 90–110, width of gnathosoma 105–140. Stylophore with 13–14 segmented peritremes (Fig. 15B). Palpal setation similar with that of deutonymph, except presence of seta l” on genu. Tibial claw very thick, attenuate distally and slightly curved. Seta d of femur blunt-ended and located very close to inner lateral surface of segment. Femur and genu partly fused by outer lateral surfaces.Adoral setae pointed; ventral surfaces of palp and subcapitulum with sparse small round dimples.
Legs (Figs 13, 14). Lengths of legs: I 320–450, II 250–320, III 235–295, IV 235–300. Leg I (Fig. 13A). Leg setation: Tr 1 (v’ N 1), Fe 3 (d, l’ Ad, bv”), Ge 2 (d, k), Ti 5(1) (d, l’ N 1, l”, v’, v”, φ), Ta 13(1) (tc’ξ, tc” ξ, p’ ξ, p”ξ, a’, a”, pl’ξ, u’, u”, pv’ N 2, pv” N 1, bl’ Ad, bl” Ad, ω); lengths of solenidia: ω 46–52, φ 105–110. Setae v’ of femur and (bl) of tarsus barbed and pointed; other setae as in deutonymph. Leg II (Fig. 13B). Leg setation: Tr 1 (v’ N 1), Fe 3 (d, l’ Ad, bv”), Ge 1 (k), Ti 5 (d, l’ N 1, l”, v’, v”), Ta 12(1) (tc’, tc”, p’ ξ, p”ξ, a’, a”, u’, u”, pv’ N 2, pv” N 1, bl’ Ad, bl” Ad, ω); solenidion ω 52–59; setae v’ of femur and (bl) of tarsus barbed and pointed; other setae as in deutonymph. Leg III (Fig. 14A). Leg setation: Tr 1 (v’ N 1), Fe 2 (d, l’ Ad,), Ge 0, Ti 4 (d, l”, v’, v”), Ta 10(1) (tc’, tc”, a’, a”, u’, u”, pv’ N 2, pv” N 1, bl’ Ad, bl” Ad, ω ♂); male solenidion ω ♂ 55–67 long and thin; setae v’ of femur and (bl) of tarsus barbed and pointed; other setae as in deutonymph. Leg IV (Fig. 14B). Leg setation: Tr 1 (v’ N 2), Fe 1 (d N 1, l’ Ad,), Ge 0, Ti 4 (d N 1, l” N 1, v’ N 1, v” N 1), Ta 8 (tc’ N 1, tc” N 1, a’ N 1, a” N 1, u’ N 1, u” N 1, pv’ N 2, pv” N 2, bl’ Ad, bl” Ad, ω ♂); male solenidion ω ♂ 60–70 long and thin; setae v’ of femur and (bl) of tarsus barbed and pointed; other setae as in deutonymph.
Material examined: 1 female, 2 males, Russia, Tyumen Province, Tyumen region, vicinity of settlement Uspenka, on the bark of dead spruce, 25 May 2019, coll. Khaustov A.A.; 7 females, same locality, 28 June 2019; 2 females, 1 PN, 1 DN, Russia, Tyumen, Zatyumenskiy park, on the bark of dead spruce, 15 June 2019, coll. Khaustov A.A.; 2 larvae, 5 PN, same locality, 9 June 2019; 1 male, 2 DN, same locality, 23 June 2019.
description: Published as part of Khaustov, Alexander A., 2020, First description of male and immatures in mite genus Dasythyreus (Acari: Dasythyreidae), pp. 196-214 in Zootaxa 4857 (1) on pages 197-206, DOI: 10.11646/zootaxa.4857.1.10, http://zenodo.org/record/4396353