Troxodania problematica ( Mahunka, 1975 ) Khaustov & Frolov, 2018

Khaustov, Alexander A. & Frolov, Andrey V., 2018, A new species, new genus and new records of heterostigmatic mites (Acari: Heterostigmata) phoretic on scarab beetles of the subfamily Orphninae (Coleoptera: Scarabaeidae), Zootaxa 4514 (2), pp. 181-201 : 188-189

Troxodania problematica ( Mahunka, 1975) comb. nov.

( Figs 6–10 )

Bakerdania problematica Mahunka, 1975, p. 69 , Figs 20A-F.

Redescription. FEMALE ( Figs 6–10 ). Length of idiosoma 245–255, width 160–165.

Gnathosoma ( Fig. 7 ). Gnathosomal capsule almost round in outline, length 23–25, width 24–27. Dorsum with two pairs of distinctly barbed and pointed cheliceral setae cha 12–13 and chb 17–18. Dorsal median apodeme present, weakly developed. Postpalpal setae (pp) needle-like and blunt-ended, situated anterolaterally to setae cha. Ventral gnathosoma with one pair of smooth, pointed subcapitular setae m 9–10 and round pits situated posteriorly to setae m. Palps with smooth, pointed setae dFe and dGe dorsolaterally; setae dGe distinctly longer than dFe. Palps ventrally each with mushroom-like ass and small finger-shaped solenidion laterally to ass. Palps terminated with small tibial claw and tiny eupathidium-like seta; palpal tibiotarsus usually completely covered by anterior part of femorogenu. Pharyngeal pumps not clearly visible.

Idiosomal dorsum ( Figs 6A , 10A ). Only posterior part of prodorsum covered by anterior part of tergite C. All dorsal shields with numerous tiny, barely discernable dimples ( Fig. 10A ). Prodorsal shield with two pair of setae (v 2, sc 2), one pair of weakly barbed capitate trichobothria and one pair of round stigmata ( Fig. 10A ). Stigmata associated with well developed tracheal trunks branched posteriorly. All dorsal setae barbed. Setae c 2 and h 2 pointed, other dorsal setae moderately blunt-ended. Cupules ia on tergite D and ih on tergite H small, round. Posterior margin of tergite H with subtriangular median projection. Setae h 2 situated on the same transverse level as h 1. Lengths of dorsal setae: v 2 13–14, sc 2 55–60, c 1 55–61, c 2 70–72, d 66–69, e 31–33, f 84–91, h 1 73–74, h 2 73–74. Distances between setae: v 2 –v 2 59 –62, sc 2 –sc 2 51–52, c 1 – c 1 69–70, c 1 – c 2 28–30, d–d 72–78, e–f 10–11, f–f 86–90, h 1 – h 1 40–45, h 1 – h 2 16–17.

Idiosomal venter ( Figs 6B , 10B ). All ventral plates with numerous tiny dimples ( Fig. 10B ). All ventral setae barbed and pointed. Ap1 well developed and joined with appr; ap2 vestigial; apsej well developed, thick; ap3 very weak, linear, joined with appo; ap4 well developed, exceeding far beyond bases of setae 3 b. Apodemes 5 absent. Ags and pgs small, subrectangular; median genital sclerite (mgs) small, oval. Posterior margin of posterior sternal plate almost straight. Posterior margin of aggenital plate rounded. Lengths of ventral setae: 1 a 40–50, 1 b 32–37, 2 a 43–46, 2 b 24–30, 3 a 36–38, 3 b 36–37, 3 c 32–34, 4 a 32–34, 4 b 44–45, 4 c 38–40, ps 1 30–31, ps 2 28–32, ps 3 25–28.

Legs ( Figs 8 , 9 , 10C ). Leg I ( Figs 8A , 10C ) distinctly thicker and slightly shorter than leg II. Setal formula: 1– 3–4–16 (4). Tibiotarsus strongly enlarged, with massive blunt-ended claw ( Fig. 10C ). Seta tc” situated on short and wide pinnaculum. Solenidion ω 1 thumb-like, other solenidia weakly clavate. Lengths of solenidia ω 1 6, ω 2 5, φ 1 6– 7, φ 2 4–5. Seta d of femur hook-like; seta l’ of femur blunt-ended and smooth, other setae (except eupathidia) pointed and barbed. Leg II ( Fig. 8B ). Setal formula: 1–3–3–4(1)–6(1). Tarsus with thickened padded claws and flipper-like empodium. Solenidia ω 6–7 clavate and φ 3–4 weakly clavate. All setae barbed. Seta d of femur bluntended, other setae pointed. Leg III ( Fig. 9A ). Femur divided into basi- and telofemur. Setal formula: 1–2–2–4(1)–6. Claws and empodium of same shape as on tarsus II. Solenidia φ 3–4 weakly clavate All setae barbed. Seta d of femur blunt-ended, other setae pointed. Leg IV ( Fig 9B ). Femur divided into basi- and telofemur. Setal formula: 1– 2–1–4(1)–6. Claws simple, hooked, empodium smaller than those on tarsi II and III. Solenidion φ 2–3 weakly clavate. All setae barbed. Setae d of femur blunt-ended, other setae pointed.

MALE and LARVA unknown.

Material examined. SRI LANKA: 3 females on Orphnus mysoriensis, Kala Oya 7.II.1983 . BURKINA FASO: 4 females on Orphnus macleayi Laporte de Castelnau and 2 females on Orphnus subfoveatus Fairmaire, Ouagadougou , 6.VI.1927, G. Olsoufieff leg.

Remarks. We accommodated this species in the genus Troxodania because of the presence of the median genital sclerite, small anterior and posterior genital sclerites and characteristic shape (strongly thickened, oval) of tibiotarsus I. Troxodania problematica ( Mahunka, 1975) comb. nov. was described from Ghana, collected on fruits ( Mahunka 1975). Examined specimens from Africa and Sri Lanka fit well with the original description of T. problematica .

Figures

FIGURE 6. Troxodania problematica (Mahunka, 1975) comb. nov., female: A—dorsum of the body, B—venter of the body. Legs omitted.

FIGURE 7. Troxodania problematica (Mahunka, 1975) comb. nov., female: A—gnathosoma in dorsal view, B—gnathosoma in ventral view.

FIGURE 8. Troxodania problematica (Mahunka, 1975) comb. nov., female: A—left leg I in dorsal view, B—left leg II in dorsal view.

FIGURE 9. Troxodania problematica (Mahunka, 1975) comb. nov., female: A—left leg III in dorsal view, B—left leg IV in dorsal view.

FIGURE 10. DIC micrographs of Troxodania problematica (Mahunka, 1975) comb. nov., female: A—prodorsum, Banterior part of posterior sternal plate, C—claw on tibiotarsus I.