Athyreacarus grandis, Khaustov & Frolov, 2019

Khaustov, Alexander A. & Frolov, Andrey V., 2019, Revision of the genus Athyreacarus (Acari: Athyreacaridae), Zootaxa 4647 (1), pp. 168-225 : 174-178

publication ID	https://doi.org/ 10.11646/zootaxa.4647.1.14
publication LSID	lsid:zoobank.org:pub:4AD08401-412E-4A7C-AAD4-3B524B8DBB8F
persistent identifier	https://treatment.plazi.org/id/14654C1D-1C79-A260-B0D4-FF526E0287D8
treatment provided by	Plazi
scientific name	Athyreacarus grandis
status	sp. nov.

Treatment

Athyreacarus grandis sp. nov.

( Figs 1–7 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 )

Description. Female ( Figs 1–7 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 ). Body elongate, almost fusiform. Length of idiosoma 505 (460–575), width 275 (250–300). This is one of the largest known heterostigmatic mite species.

Gnathosoma ( Figs 6B View FIGURE 6 , 7A View FIGURE 7 ). Gnathosomal capsule, excluding palps, almost oval, length 53 (50–55), width 57 (52–57). Dorsally with one pair of barbed, blunt-ended cheliceral setae cha 23 (21–27). Postpalpal setae (pp) 12 (12–13). Subcapitular setae m 10 (9–11) and n 55 (53–62) ( Fig. 7A View FIGURE 7 ) smooth. Setae m blunt-ended, n pointed. Setae dFe 28 (15–30) and dGe 39 (32–40) smooth and pointed. Tibial claw well-developed, slightly hooked.

Idiosomal dorsum ( Figs 1A View FIGURE 1 , 4A View FIGURE 4 , 5B View FIGURE 5 , 6 View FIGURE 6 A–E). All dorsal shields with numerous dimples ( Fig. 5B View FIGURE 5 ). Central part of tergite C in some specimens with very weak subcuticular reticulation. Dorsal shields wide, almost completely covering idiosoma. Prodorsal shield without lateral projections, setae v 2 and sc 1 vestigial ( Fig. 6D View FIGURE 6 ). Setae sc 2, c 2, d, f, h 1, and h 2 with distinctly thickened basal half. Setae e short, spiniform. Setae c 1 absent. All dorsal setae smooth. Setae e usually blunt-ended, other dorsal setae pointed. Cupules ia on tergite D, im, ip on tergite EF and ih on tergite H small, round. Cupules ih located lateroventrally. Pseudanal segment unusually long, only slightly shorter than tergite H. Lengths of dorsal setae: v 1 95 (75–97), sc 2 51 (43–53), c 2 50 (46–55), d 44 (47–49), e 7 (6–10), f 33 (32–38), h 1 33/39 (23–40), h 2 36/52 (22–52). Distances between setae: v 1 –v 1 44 (44–50), v 2 –v 2 105 (105–120), sc 1 –sc 1 115 (115–130), sc 2 –sc 2 92 (88–93), c 2 – c 2 185 (170–200), d–d 97 (88–100), e–e 98 (95–105), f–f 84 (83–93), h 1 – h 1 70 (70–82), h 1 – h 2 18 (17–29).

Idiosomal venter ( Figs 1B View FIGURE 1 , 4B View FIGURE 4 , 5A, C, D View FIGURE 5 , 6F View FIGURE 6 , 7 View FIGURE 7 B–D). All ventral plates with numerous dimples ( Fig. 5A, C, D View FIGURE 5 ), dimples on aggenital and midsternal plates located more densely than on other plates. All ventral setae smooth and pointed, sometimes seta ag 1 blunt-ended. Ap5 short, located near base of legs IV. Aggenital plate with two pairs of aggenital setae. Anal opening terminal, with long anal valves forming cone-like structure. Length of mid-sternal plate 110 (105–120), width 90 (83–95); ratio length/width 1.2–1.3. Lengths of ventral setae: 1 a 62 (45–63), 1 b 22/44 (22–61), 1 c 45 (33–46), 2 a 74 (65–80), 2 b 54 (53–61), 2 c 36 (29–50), 3 a 35/47 (30–55), 3 b 61 (49–67), 3 c 53/70 (43–70), 4 a 54 (53–63), 4 b 60 (54–71), 4 c 36 (28–44), ag 1 34/45 (32–54), ag 2 77 (76–125), ps 1 160 (150–195), ps 2 155/170 (145–180), ps 3 120/145 (120–170).

Legs ( Figs 2 View FIGURE 2 , 3 View FIGURE 3 , 7E, F View FIGURE 7 ). Length of legs: I 170 (165–190), II 200 (185–215), III 260 (255–295), IV 345 (340– 380). Leg I ( Figs 2A View FIGURE 2 , 7E View FIGURE 7 ): all leg setae smooth; setae l’, v’ of femur, v’, l” of genu, l” and k of tibia, and pv” of tarsus blunt-ended; other leg setae (except eupathidia) pointed; setae (pl) weakly thickened and flattened subapically; lengths of solenidia ω 1 15 (15–16), ω 2 11 (11–12), φ 1 10 (10–12), φ 2 10 (9–10); ω 1 and ω 2 digitiform, φ 1 and φ 2 weakly clavate. Leg II ( Figs 2B View FIGURE 2 , 7E View FIGURE 7 ): solenidion ω 15 (14–15), digitiform solenidion φ 11 (11–12) baculiform; setae d of femur and tibia, (u) and (tc) of tarsus smooth, other leg setae weakly barbed; setae l’, v’ of femur and (tc) of tarsus blunt-ended; other leg setae pointed; setae (tc) of tarsus distinctly spatulate distally. Leg III ( Figs 3A View FIGURE 3 , 7F View FIGURE 7 ): similar in shape and length to leg II; solenidion φ 10 (10–13) baculiform; setae v’ of trochanter, d, v’ of femur, d of tibia, (u) and (tc) of tarsus smooth, other leg setae weakly barbed; seta v’ of femur, (l), v’ of genu, l’ of tibia and (tc) of tarsus blunt-ended; other leg setae pointed; setae (tc) of tarsus distinctly spatulate distally ( Fig. 7F View FIGURE 7 ). Leg IV ( Fig. 3B View FIGURE 3 ): solenidion φ 10 (10–12) baculiform; setae v’ of trochanter, d, v’ of femur, d of tibia and tc’ of tarsus smooth, other leg setae weakly barbed; seta v’ of trochanter, v’ of femur, v’, l” of genu, l ’, (v) of tibia, p’ and tc’ of tarsus blunt-ended; other leg setae pointed; seta tc’ of tarsus distinctly spatulate distally.

Type material. Female holotype, slide No. 1734.1, BRASIL, Mato Grosso, Itiquira, Fazenda Espigão , 10.I.2013, T. Semedo leg., on a beetle Neoathyreus lanuginosus ( Klug) . Paratypes : 16 females, same data ; 18 females, BRA- SIL, Minas Gerais, Conceição dos Ouros, Rio Sapucaí-Mirim , 860 m, on a beetle N. lanuginosus ; 21 females, BRASIL, Minas Gerais, Fazenda Costinha , I.1994, F.Z.Vaz-de-Mello leg., on a beetle N. lanuginosus .

Type deposition. The holotype and seven paratypes are deposited in the collection of UNESP—Universidade Estadual Paulista, Department of Zoology and Botany, 15054—000 São José do Rio Preto—SP, Brazil; 20 paratypes are deposited in the collection of the Tyumen State University Museum of Zoology , Tyumen, Russia; 10 paratypes are deposited in the collection of the Zoological Institute of RAS, Saint Petersburg, Russia.

Differential diagnosis. The new species is most similar to A. pleiotretus Lindquist, Kaliszewski and Rack, 1990 by the absence of setae c 1 and vestigial setae v 2. The new species differs from A. pleiotretus by setae sc 2, c 2, d, f, h 1, and h 2 with distinctly thickened basal half (vs. not thickened in A. pleiotretus ) ( Figs. 54A, B View FIGURE 54 ), spiniform setae e (vs. not modified in A. pleiotretus ) ( Fig. 54B View FIGURE 54 ), and small dimples on segment ps, which do not differ from dimples on tergite H and aggenital plate (vs large dimples, distinctly larger than on tergite H and aggenital plate in A. pleiotretus ) ( Figs. 54 B, D View FIGURE 54 ).