Stigmaeus silvestris Khaustov

Khaustov, Alexander A., 2014, New species and new records of mites of the genus Stigmaeus (Acari: Prostigmata: Stigmaeidae) from Crimea, Zootaxa 3794 (2), pp. 237-253 : 245-246

Stigmaeus silvestris Khaustov sp. nov.

( Figs. 18–25 , 30–32 )

Description. FEMALE. Length of idiosoma 468 (420–470), width 325 (300–320). The chaetotaxy of body and legs as in S. mitrofanovi sp. nov. Idiosomal dorsum ( Fig. 18 ). Central plate with 2 pairs of setae c 1 and d 1; intercalary plates paired. All plates coarsely reticulated; Postocular bodies of medium size, smooth ( Fig. 30 ). Eyes absent. Striation anterolateral to propodosomal plate generally without microtubercles, sometimes with few tubercles on striae above leg II ( Fig. 31 ). All dorsal setae barbed. Setae ve and c 2, longer than others and pointed. Other dorsal setae distinctly blunt-ended and barbed in distal half. Setae e 2 subequal to d 2, and distinctly shorter than sce and c 2. Ratio ve/sci = 3.0. Length of dorsal setae: vi 45, ve 89, sci 29, sce 46, c 1 34, c 2 87, d 1 40, d 2 44, e 1 35, e 2 44, f 1 50, h 1 46, h 2 54. Distances between setae: vi-vi 20, ve-ve 59, sci-sci 129, c 1 -c 1 78, d 1 -d 1 65, h 1 -h 1 46, h 1 -h 2 29. Idiosomal venter ( Fig. 19 ). All ventral plates reticulated. All ventral setae pointed and smooth, except for bluntended and barbed h 1. Length of ventral setae: 1 a 22, 1 b 20, 1 c 41, 2 b 35, 2 c 30, 3 a 25, 3 b 23, 3 c 25, 4 a 23, 4 b 21, 4 c 19, ag 1 22, ag 2 20, ag 3 22, g 17, ps 1 34, ps 2 27, ps 3 28. Gnathosoma ( Figs. 20–21 ). Tibial claw large. All setae on femur, genu and tibia of palps are pointed, except for spine-like l’ on palpal tibia ( Fig. 20 ). Palpal supracoxal setae (elcp) seta-like. Rostrum of subcapitulum ( Fig. 21 ) relatively short and wide. Subcapitular setae smooth and pointed. Basal part of subcapitulum with distinct reticulation ( Fig. 32 ). Length of subcapitular setae: m 20, n 19, or 1 19, or 2 25. Legs ( Figs. 22–25 ). Empodial raylets pointed. Leg segments with reticulations. Leg I ( Fig. 22 ). Coxae I posterodorsally with seta-like leg supracoxal setae (elcl). Setae l”, d on genu and l”, d on femur blunt-ended and distinctly barbed in distal half. Seta d (28) on genu shorter than seta k (32). Solenidion ω short (16), finger-shaped; solenidion φ (12) baculiform, φp attenuate (27). Leg II ( Fig. 23 ). Setae d on tibia, p’ and tc’ on tarsus representing by eupathidia. Setae d and l” on genu and d on femur blunt-ended and distinctly barbed in distal half. Solenidion ω (15) finger-shaped; solenidion φ (23) attenuate. Seta k short (8), about 4 times shorter than setae d on genu. Leg III ( Fig. 24 ). Solenidion ω (10) finger-shaped; solenidion φ (23) attenuate. Setae d on genu and d, l’ on femur bluntended and distinctly barbed. Leg IV ( Fig. 25 ). Solenidion ω (10) finger-shaped; solenidion φ (23) attenuate. Setae d on genu and d on femur blunt-ended and distinctly barbed. Seta d on tibia long (77), almost smooth, 2.4 times longer than l’ on tibia.

Type material. Female holotype, slide № AK 110201, and 4 female paratypes, CRIMEA: Nikita mountain pasture, about 1250 m.a.s.l., in rotten log of pine, Pinus pallasiana D. Don. , 11 February 2001, coll. Khaustov A.A..

Etymology. The specific epithet refers to the distribution of new species in rotten wood in forests.

Differential diagnosis. The new species is most similar to S. uzunolukensis Özçelik and Dogan, 2011 by the presence of two setal pairs on the central plate, six and five setae on femora I and II, respectively, by having medium size postocular bodies, similar relative lengths of dorsal setae, and by the absence of eyes. It differs from S. uzunolukensis by not widened distally dorsal idiosomal setae (vs. most of dorsal idiosomal setae have distinctly widened tips in S. uzunolukensis ), by having setae ve and c 2 subequal in the length (ve is distinctly longer than c 2 in S. uzunolukensis ), and by the distinctly larger body size: length of idiosoma 469, width 325 (300–350 long and 150–200 wide in S. uzunolukensis ).

Figures

FIGURES 18. Stigmaeus silvestris Khaustov sp. nov., female: 18 — idiosomal dorsum.

FIGURES 19 – 21. Stigmaeus silvestris Khaustov sp. nov., female: 19 — opisthosomal venter, 20 — gnathosoma dorsally, 21 — anterior part of subcapitulum.

FIGURES 22 – 23. Stigmaeus silvestris Khaustov sp. nov., female: 22 – 23 – legs I – II, respectively.

FIGURES 24 – 25. Stigmaeus silvestris Khaustov sp. nov., female: 24 – 25 – legs III – IV, respectively.

FIGURES 26 – 32. Stigmaeus mitrofanovi Khaustov sp. nov., female: 26 — postocular body, 27 — anterolateral part of prodorsum showing striae with microtubercles, 28 — palpal supracoxal seta (elcp); Stigmaeus kuznetsovi Khaustov sp. nov., female: 29 — postocular body; Stigmaeus silvestris Khaustov sp. nov., female: 30 — postocular body, 31 — lateral part of prodorsum, 32 — subcapitulum.