Cunaxa oblongostriata, Kalúz & Ermilov, 2022

Kalúz, Stanislav & Ermilov, Sergey G., 2022, Two new species of Cunaxa (Acari: Prostigmata: Cunaxidae) from Vietnam, Zootaxa 5087 (4), pp. 541-557 : 543-548

Cunaxa oblongostriata sp. n.

( Figs 1–4 )

Diagnosis (female). Proterosomal shield triangular, hysterosomal median plate absent. Hysterodorsal setae of different lengths, smooth, cuticular striae between setae d 1 –d 1 longitudinal. Palpal telofemur with a short and straight apophysis, and with two relatively long palpal tibiotarsal setae. Venter with 4 pairs of sts between coxae III and genital region; 3 sts and 0 sts present on basifemora III and IV, respectively.

Description (female; mean and range for holotype and 6 paratypes). Idiosoma. Body length 426 (390–440), width 303 (270–330).

Dorsum ( Fig.1 ). Propodosoma with smooth triangular shield, cone–shaped distally. Propodosomal shield reaching to anterior region of hysterosoma, bearing a pair of anterior (at) and posterior (pt) setose trichobothria and also two pairs of tactile setae (lps, mps). Anterior trichobothrium 277 (229–336), posterior trichobothrium 302 (269–323) long, distance between bases of mps–mps and lps–lps 28 (25–30) and 141 (137–144), respectively. Propodosoma separated from hysterosoma and hysterosomal tegument bearing fine striae, without hysterosomal shields or platelets. Six pairs of tactile setae present on dorsal hysterosoma; c 2, c 1 –h 1. Length of setae c 1 27 (25–29), c 2 21 (20–22), d 1 23 (18–28), e 1 26 (24–28), f 1 51 (44–54) and h 1 54 (52–59). Distance between bases of setae c 1 –c 1 98 (82–104) about three times length of c 1; d 1 –d 1 72 (64–81) about two and half times length of d 1; e 1 –e 1 93 (86–102) about three-four times longer e 1; f 1 –f 1 53 (44–62), as long as length of f 1; h 1 –h 1 39 (37–40) shorter than length of h 1, cupule im present.

Venter ( Fig.2 ). Coxal plates very weakly sclerotized, coxae I–II and III–IV contiguous and finely striated. Setal formula of coxae I–IV: 3-1-3-2 sts. Venter of hysterosoma ( Fig. 2 ) with a pair of simple centro–medial setae 21 (21– 22) between coxae III on longitudinally striated integument, and with 3 pairs of hysterogastral setae 22 (21–23) on transversally striated integument arranged anteriorly to genital plates. Two pairs of genital plates - each 58 (53–64) long and 29 (25–36) wide and with four pairs of simple setae on weakly sclerotized genital plates, setae increasing in length caudally: g 1 21 (19–23); g 2 22 (20–23); g 3 27 (22–29); g 4 26 (23–29), and two pairs of adjacent ps setae; ps 2 13 (12–14), ps 1 13 (10–15), close to anal plates.

Gnathosoma ( Fig. 3A–C ). Five–segmented palp 208 (202–213) long with palpal tibiotarsus slightly apically curved. Palp ( Fig. 3A ) with gently punctate surface. Palpal chaetotaxy as follows: trochanter—without setae; basifemur 80 (76–84) long with—1 dorso–medial simple seta 9 (8–10) long] inner surface of telofemur 47 (44–52) with 1 latero–medial apophysis 13 (11–15), dorso–distal seta 9 (9–10); inner ventral surface of genu 43 (40–45) long with 1 latero–distal spine–like seta 16 (14–18), dorsally with 1 latero–distal spine–like seta 9 (8–9) and ventrally with latero–distal seta 11 (9–12); tibiotarsus 71 (68–73) inner surface with 1 long simple proximal seta 32 (29–39) and medially with 1 stout spine–like seta 17 (15–19), medio–lateral simple seta 20 (19–23); outer surface with 1 dorso–distal simple seta 10 (9–11), dorso–distal solenidion 7 (7–8) and terminating with small short claw.

Chelicera ( Fig. 3C ). Slender, 156 (153–159) long and 26 (22–34) wide at widest part; cheliceral segment I as well as the proximal part of segment II with fine punctation, distal seta 11 (9–13) present.

Subcapitulum ( Fig. 3B ). Robust, 169 (160–168) long, with almost rounded basal part 75 (62–85) long and 93 (88–98) wide, subcapitulum distally cone–shaped with two pairs of short adoral setae and four pairs of hypognathal setae (hg). Setae hg 4 48 (43–51) long, about two times longer than hg 2 24 (21–29), three times longer than hg 1 14 (12–17) and about two times longer than hg 3 29 (28–31). Coxal region of subcapitulum finely punctate, basal subcuticular reticulate structure weakly developed.

Legs ( Fig.4 ). All legs smooth, legs I–III shorter than leg IV. Chaetotaxy I–IV (excluding coxae) as follows: trochanters 1-1-2-1 sts; basifemora 3-3-3-1 sts; telofemora 4-4-4-4 sts; genu I—2 asl, (1asl,1 mst), 5 sts; genu II—3asl, 4sts; genu III –5 sts; genu IV—7 sts; tibia I—1 asl, (1 asl, 1 mst), 4 sts; tibia II—1 asl, 5 sts; tibia III—1 bsl, 5 sts; tibia IV—1 smooth T, 4 sts; tarsus I—5 asl, famulus,1 dtsl, 11 sts, pretarsus with 1 dorsal and 1 ventral sts on each lobe; tarsus II—1 asl, 1 dtsl, 16 sts, pretarsus with 1 dorsal and 1 ventral sts on each lobe; tarsus III—9 sts, 1 dtsl, pretarsus with 1 dorsal and 1 ventral sts on each lobe; tarsus IV—10 sts, 1 dtsl, pretarsus with 1 dorsal and 1 ventral sts on each lobe. Length/width of leg segments I – IV (coxa and trochanter not measured): basifemur 80 (76–84)/27 (21–30); telofemur 47 (44–52)/ 26 (20–34); genu 29 (28–30)/ 19 (18–21); tibia 43 (40–45)/ 18 (15–19); tarsus 153 (150–155)/ 6 (5–7) wide at distal part.

Male and developmental stages: Unknown.

Material examined. Holotype: locus typicus: Vietnam, Dong Nai Province, Dong Nai Culture and Nature Reserve, Dipterocarp forest, 11°18’N, 107°04’E, soil and litter (sifter), 20 December 2013, coll. A.E. Anichkin and S.G. Ermilov— 1 female. Paratypes: same collection data as for holotype — 1 female; Vietnam, Dong Nai Province, Dong Nai Biosphere Reserve, 11°21′– 11°48′N, 107°10′– 107°34′E, polydominant forest, soil and litter (sifter), 30 November 2013 – 01 December 2013, coll. A.E. Anichkin and S.G. Ermilov — 3 females; Vietnam, Lam Dong Province, Bi Dup—Nui Ba National Park, mixed pine dominated forest, 12º10’– 12º11’N, 108º40’– 108º41’E, soil and litter (sifter), 06–07 December 2013, coll. A.E. Anichkin and S.G. Ermilov — 1 female; Vietnam, Binh Phuoc Province, Bu Gia Map National Park, mixed forest (mainly Dilleniaceae , Lecythidaceae , Anacardiaceae , Verbenaceae , Irvingiaceae and others), 12º05’– 12º18’N, 107º03’– 107º14’E, soil and litter (sifter), 13–14 November 2013, coll. A.E. Anichkin and S.G. Ermilov— 1 female.

Type deposition. Holotype and 3 paratypes at SNMB, 3 paratypes — MNSB.

Etymology. The name of a new species reflects the longitudinal striations in the central part of dorsum.

Remarks. The new species Cunaxa oblongostriata sp. n. is most similar to C. setirostris (Hermann, 1804) in having chaetataxy of basifemora I–IV: 3-3-3-1 sts, dorsal setae of unequal length, and by the absence of the hysterosomal medial plate. The new species differs from the above-mentioned species in having the propodosomal shield triangular and cuticular striae between d 1 –d 1 longitudinal, while in C. setirostris , the propodosomal shield is trapezoidal, with the posterior part twice as wide as the anterior part, and cuticular striae between dorsal setae d 1 –d 1 are transversal.

Figures

FIGURE1. Cunaxa oblongostriata sp. n., dorsal view of female idiosoma.

FIGURE2. Cunaxa oblongostriata sp. n., ventral view of female idiosoma.

FIGURE3. Cunaxa oblongostriata sp. n., gnathosoma of female. A—palp, dorsal view, B—subcapitulum, ventral view, C— chelicera, dorsal view.

FIGURE4. Cunaxa oblongostriata sp. n., legs I–IV of female (left side, dorsal view).