Athyreacarus pusillus Khaustov & Frolov 2019, sp. nov.
Creators: name: Khaustov, Alexander A.
name: Frolov, Andrey V.
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Actinedida
Athyreacaridae
Athyreacarus
Athyreacarus pusillus

description: Athyreacarus pusillus sp. nov.
(Figs 33–37)
Description. Female (Figs 33–37). Body fusiform. Length of idiosoma 230 (240, 270), width 125 (130, 155).
Gnathosoma. Gnathosomal capsule, excluding palps, almost oval, length 44 (42, 45), width 46 (45, 53). One pair of barbed, blunt-ended cheliceral setae cha 20 (20, 21). Postpalpal setae (pp) 5 (4, 5) needle-like. Subcapitular setae m 11 (10, 12) and n 22 (24, 25) pointed and weakly barbed. Setae dFe 12 (13) and dGe 22 (20, 21) barbed and blunt-ended. Tibiotarsus dorsomedially with well developed rodlike eupathid. Tibial claw small, slightly hooked.
Idiosomal dorsum (Figs 33A, 36A, 37A, B). All dorsal shields with numerous small sparsely distributed dimples (Figs 37A, B). Hysterosomal shields almost completely covering hysterosoma and only lateral margins with soft cuticle. Prodorsal shield without lateral projections, only alveoli of setae sc 1 present. All dorsal setae blunt-ended and barbed. Cupules ia on tergite D, im on tergite EF, and ih on tergite H small, round. Pore-like structures on tergites C, D, and EF not evident. Cupules ip on tergite EF not evident. Cupules ih located dorsally, anterolaterally to bases of setae h 1. Pseudanal segment much shorter than tergite H. Lengths of dorsal setae: v 1 45 (45, 47), v 2 24 (23, 24), sc 2 72 (80, 81), c 1 26 (26, 29), c 2 69 (73, 87), d 80 (81, 94), e 21 (12, 17), f 96 (100, 105), h 1 61 (66, 72), h 2 21 (20–21). Distances between setae: v 1 –v 1 13 (15, 17), v 2 –v 2 37 (39, 42), sc 1 –sc 1 42 (45, 47), sc 2 –sc 2 38 (37, 42), c 1 – c 1 42 (42, 47), c 1 – c 2 27 (26, 32), d–d 46 (46, 54), e–e 44 (41, 47), f–f 46 (47, 49), h 1 – h 1 32 (34, 35), h 1 – h 2 11 (11).
Idiosomal venter (Figs 33B, 36B, 37C, D). All ventral plates with numerous small dimples (Figs 37C, D), dimples on aggenital and midsternal plates arranged slightly more densely than on other plates. All ventral and caudal setae weakly barbed and blunt-ended, except pointed ps 3. Ap1 slightly thickened, ap5 long, reaching beyond bases of setae 4 a. Aggenital plate with two pairs of aggenital setae. Anal opening subterminal. Length of mid-sternal plate 46 (44, 46), width 46 (43, 44); ratio length/width 1.0–1.1. Lengths of ventral setae: 1 a 17 (15, 18), 1 b 10 (11), 1 c 16 (14), 2 a 20 (20, 21), 2 b 15 (16), 2 c 10 (10, 11), 3 a 14 (14, 15), 3 b 16 (16, 17), 3 c 16 (15, 16), 4 a 16 (15, 17), 4 b 18/22 (19, 20), 4 c 15 (13, 16), ag 1 15 (12, 16), ag 2 16 (14, 16), ps 1 40 (45, 46), ps 2 35 (33, 42), ps 3 21 (21, 22).
Legs (Figs 34, 35). Length of legs: I 90 (85, 90), II 72 (75, 77), III 90 (86, 90), IV 105 (105, 110). Leg I (Fig. 34A): setae v’ of trochanter, v’ of femur, k of tibia, and pv” of tarsus smooth, other leg setae (except eupathidia) weakly barbed; setae l’, v” of genu, d, l’, v” of tibia, (pl), s and pv’ of tarsus pointed, other leg setae blunt-ended; lengths of solenidia ω 1 12 (9, 12), ω 2 7 (8, 9), φ 1 9 (8, 11), φ 2 7 (6, 7); ω 1 and φ 1 digitiform, ω 2 and φ 2 clavate. Leg II (Fig. 34B): solenidion ω 11 (12, 13) digitiform, solenidion φ 5 (4, 5) clavate; all leg setae barbed; setae v’ of trochanter, d, v’, l’ of femur, v’, l’, l” of genu, l’ of tibia, (tc) and pl” of tarsus blunt-ended, other leg setae pointed. Leg III (Fig. 35A) similar in shape and length to leg II; solenidion φ 5 (4) clavate; all leg setae barbed; setae d, v ’, v ” of tibia pointed, other leg setae blunt-ended. Leg IV (Fig. 35B): solenidion φ 3 (4) clavate: all leg setae barbed; seta v” of tibia pointed, other leg setae blunt-ended.
Type material. Female holotype, slide No. 1738.1, BRASIL, Distrito Federal, Brasilia, III.2001, N. Degallier leg., on a beetle A. brasilicus. Paratypes: 2 females, same data.
Type deposition. The holotype is deposited in the collection of UNESP—Universidade Estadual Paulista, Department of Zoology and Botany, 15054—000 São José do Rio Preto—SP, Brazil; two paratypes are deposited in the collection of the Tyumen State University Museum of Zoology, Tyumen, Russia.
Differential diagnosis. See differential diagnosis for A. vazdemelloi.
Etymology. The name of the new species derives from the Latin word “ pusillus ” meaning “ tiny ” and refers to the very small body size of females of this species.
description: Published as part of Khaustov, Alexander A. & Frolov, Andrey V., 2019, Revision of the genus Athyreacarus (Acari: Athyreacaridae), pp. 168-225 in Zootaxa 4647 (1) on pages 199-202, DOI: 10.11646/zootaxa.4647.1.14, http://zenodo.org/record/3352927