Cheletogenes vietnamiensis Khaustov, Salavatulin, Tsurikov, Thinh & Khaustov, 2024, sp. nov.
Creators: name: Khaustov, Alexander A.
name: Salavatulin, Vladimir M.
name: Tsurikov, Sergey M.
name: Thinh, Nguyen Van
name: Khaustov, Vladimir A.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Trombidiformes
Cheyletidae
Cheletogenes
Cheletogenes vietnamiensis

description: Cheletogenes vietnamiensis sp. nov.
(Figures 1–16)
Description. Female (n=19) (Figs 1–7). Length of idiosoma 240 (225 – 255), width 190 (175 – 190).
Dorsum (Figs 1A, 5, 7B, C). Prodorsum with eight pairs of fan-shaped setae; setae vi distinctly larger than other dorsal setae (Fig. 7B). Main part of prodorsum with cuticular tubercles; cuticle between tubercles weakly striated (Fig. 7B); setae c2 situated on small platelets. Hysterosomal dorsum with eight pairs of fan-shaped setae, smaller than those on prodorsum; hysterosomal shield poorly sclerotized, weakly striated, subtriangular, with one pair of setae e1 (Fig. 7C); other dorsal hysterosomal setae situated on small platelets. Cuticle around hysterosomal shield with tubercles and striae between them; lateral and posterior parts of hysterosomal dorsum striated. Lyrifissures im and ip not evident. Cuticle between gnathosoma and prodorsal shield punctate. Lengths of dorsal setae: vi 33 (30– 33), ve 23 (20–23), si 21 (18–21), se 16 (14–16), anterior prodorsal dorsocentral setae 20 (18–20), middle prodorsal dorsocentral setae 19 (17–19), posterior prodorsal dorsocentral setae 18 (16–18), c2 15 (14–17), d1 16 (14–16), d2 16 (13–16), e1 14 (13–14), e2 14 (13–14), f1 15 (12–15), f2 15 (12–15), h1 15 (13–15), h2 13 (12–14).
Venter (Figs 1B, 6, 7D). Idiosomal venter with three pairs of intercoxal (1a, 3a, 4a), three pairs of aggenital (ag1–ag3), two pairs of genital (g1, g2), and three pairs of pseudanal setae (ps1–ps3); coxisternal fields I with two setae (1b, 1c), coxisternal fields II with one seta (2c), coxisternal fields III with two setae (3b, 3c), and coxisternal fields IV with two setae (4b, 4c). Ventral soft cuticle with small granules (Fig. 7D). Lyrifissures ih located laterad genital setae. Setae 3b blunt-tipped and weakly barbed; other ventral setae smooth and pointed. With two pairs of smooth elongate cuticular areas posteriad coxisternal fields II and laterad setae 3a.
Gnathosoma (Figs 2, 7A). Protegmen smooth, with only a few longitudinal striae laterally; tegmen with median depression and characteristic ornamentation as in Figure 7A. Peritremes with 8-9 pairs of arch-like segments; posterior segment characteristically bent medially. Palpal supracoxal setae (ep) hidden under lateral parts of peritremes. Palpal femur and genu fused laterally. Palpfemur with one broadly lanceolate and strongly barbed dorsal (d) and two smooth, filiform ventral setae, (v’, v”); palpgenu with one fan-shaped dorsal (d) and lanceolate, strongly barbed lateral seta (l”); palptibia with three setae: smooth and pointed d situated near anterior margin of flat anteromedian flange, filiform l’, and broadly lanceolate and strongly barbed l”; setae d on femur and genu situated on short protuberances. Tibial claw with 6–8 processes. Tarsus with two comb-like setae (acm, sul), two sickle-like eupathidia (ul’ϛ, ul”ϛ) and one baculiform solenidion (ω); inner comb-like seta (acm) with 15-19 projections; outer comb-like seta (sul) with 11–14 projections. Adoral setae smooth, pointed; ao1 slightly shorter than ao2. Subcapitulum finely punctate, with one pair of long filiform setae n.
Legs (Figs 3, 4). Lengths of legs: leg I 130 (115–130), leg II 120 (110–120), leg III 130 (125–135), leg IV 145 (135–150). Leg I (Fig 3A). Tarsus with short solenidion ω 8 (8–9) situated on prominent nipple; seta ft minute, hardly discernible, situated near the base of solenidion; with two blunt-tipped tectal eupathidia (tc’ϛ, tc”ϛ) as long as leg I; tarsus with one pair of ventrodistal unguinal setae (u’, u”), both smooth, pointed and short (Fig. 3 A’); other tarsal setae absent. Tibia with one fan-shaped seta (d), three lanceolate setae (l”, v’, v”), and tiny club-shaped dorsodistal solenidion φ 2 (2); genu with two fan-shaped setae (d, l’) and short rod-like dorsodistal sensory seta k 2 in shallow depression; femur with one fan-shaped seta (d) and one lanceolate seta (v’); trochanter with one lanceolate seta (v’); leg supracoxal seta (el) weakly clavate, similar in shape to k on genu, situated dorsomesad trochanter and usually covered by lateral margins of idiosomal soft cuticle. Leg II (Fig. 3B). Tarsus with three smooth and pointed setae (tc’, tc”, vs), two weakly barbed, curved and slightly thickened setae (a’, a”), two filiform pointed and with long barbs unguinal setae (u’, u”), and lateral baculiform solenidion ω 12 (10–12); tibia with one fan-shaped seta (d), one lanceolate seta (l”), and two filiform smooth and pointed setae (v’, v”); genu with one dorsal fan-shaped seta (d) and one broadly lanceolate lateral seta (l’); femur with one dorsal fan-shaped seta (d) and one ventral lanceolate seta (v”); trochanter with one baculiform and barbed seta (v’). Leg III (Fig. 4A). Tarsus with three smooth pointed setae (tc’, tc”, vs), two weakly barbed, curved and slightly thickened setae (a), and wo filiform pointed and with long barbs unguinal setae (u’, u”); tibia with two broadly lanceolate setae (d, l”), one narrowly lanceolate seta (v’), and one filiform smooth and pointed seta (v”); genu with one dorsal fan-shaped seta (d) and one broadly lanceolate lateral seta (l’); femur with one dorsal fan-shaped seta (d) and one ventral lanceolate seta (v’); trochanter with two narrowly lanceolate setae (l’, v’). Leg IV (Fig. 4B). Tarsus with three smooth pointed setae (tc’, tc”, vs), two weakly barbed, curved and slightly thickened setae (a), and wo filiform pointed and with long barbs unguinal setae (u’, u”); tibia with two broadly lanceolate seta (d, l”), one narrowly lanceolate seta (v’), and one filiform smooth and pointed seta (v”); genu with one dorsal fan-shaped seta (d) and one broadly lanceolate lateral seta (l’); femur with one dorsal fan-shaped seta (d); trochanter with one baculiform and weakly barbed seta (v’).
Male (n=13) (Figs 8, 9). Length of idiosoma 160–175, width 145–155.
Idiosoma similar to that of female, except following character states: opisthosoma narrower posteriorly; setae h1 and ps1 smooth, baculiform, setae h2 smooth and weakly clavate; genital setae absent; idiosomal venter with smooth striae; tegmen without distinct depression. Aedeagus simple, slightly curved and attenuate distally.
Legs (Fig. 9). In general leg setation as in female, except presence of well-developed ventral solenidia on tarsi III and IV, and relatively longer solenidia on tibiae I and II. Lengths of legs: leg I 95–105, leg II 91–100, leg III 95–105, leg IV 100–110. Lengths of solenidia and seta k: ω I 11–12, φ I 3, k 2, ω II 14–19, ω III 16–20, ω IV 20–24.
Tritonymph (n=20) (Fig. 10). Length of idiosoma 210–220, width 165–175.
Dorsum as in female.
Venter (Fig. 10). Similar to that of female, except presence of only two pairs of aggenital and one pair of genital setae, and ventral striae smooth.
Gnathosoma and legs as in female. Lengths of legs: leg I 105–115, leg II 100–110, leg III 105–115, leg IV 110–120.
Protonymph (n=16) (Figs 11–12). Length of idiosoma 145–150, width 125–140.
Dorsum (Fig. 10A). Prodorsum with seven pairs of setae (Fig. 11A); hysterosomal dorsum with six pairs of setae (d1, d2, e, f1, f2, h1); setae h1 usually located ventrally; hysterosomal shield without setae.
Venter (Figs 11C, D). Idiosomal venter with two pairs of intercoxal (1a, 3a), one pair of aggenital (ag1), and three pairs of pseudanal setae (ps1–ps3). Coxisternal fields I–III as in female; coxisternal fields IV without setae. Ventral striae smooth.
Gnathosoma (Fig. 11C) similar to that of female except absence of setae l” of genu and v’ of femur.
Legs (Fig. 12). Lengths of legs: leg I 85–92, leg II 77–83, leg III 84–90, leg IV 85–91. Setation of legs similar to that of female, except the following: trochanters I, II and IV without setae; trochanter III with one seta (l’); femur III with one seta (d); genu IV without setae; tarsus IV without setae vs and a”.
Larva (n=5) (Figs 13–16). Length of idiosoma 140–160, width 120–135.
Dorsum (Figs 13A, 14). All dorsal setae broadly lanceolate. Prodorsum with six pairs of setae (vi, ve, si, se, c1, c2); hysterosoma without dorsal shied; with five pairs of setae (d1, d2, e, f1, f2).
Venter (Fig. 13B). Idiosomal venter with two pairs of intercoxal (1a, 3a), three pairs of pseudanal (ps1–ps3), and one pair of setae h1. Coxisternal fields I each with one seta (1b), coxisternal fields II and III without setae. All ventral setae smooth and pointed.
Gnathosoma (Fig. 15). In general similar to that of protonymph, except absence of setae n on subcapitulum and v” on palpfemur.
Legs (Fig. 16). Lengths of legs: leg I 66–70, leg II 63–67, leg III 69–72. In general legs I–III similar to those of protonymph, except the following: tarsus I with only one long eupathid-like seta (tc”ϛ), seta tc’ very short; trochanter III without seta; genua II and III with one seta each (l’); tarsi II and III without setae vs and a”.
Type material. Female holotype, slide VS201122, Vietnam, Cat Tien National Park, on Dipterocarpus alatus; crown, branches at the height of 20–25 m; 11°26′35.11′′ N, 107°26′01.38′′ E; 20.XI.2022 – 10.XII.2022, collected by V.M. Salavatulin; paratypes: 8 females, 6 males, 4 TN, 6 PN, 1 larva, same data; 9 females, 6 males, 16 TN, 10 PN, 4 L, Vietnam, Cat Tien National Park, on Dipterocarpus alatus; crown, branches at the height of 20–25 m; 11°26′34.97′′ N 107°26′02.64′′ E; 20.XI.2022 – 10.XII.2022, collected by V.M. Salavatulin; 1 female, 1 male, Vietnam, Cat Tien National Park, on Dipterocarpus alatus; crown, branches at the height of 20–25 m; 11°26′30.60′′ N, 107°25′56.15′′ E; 20.XI.2022 – 10.XII.2022, collected by V.M. Salavatulin.
Type deposition. The holotype and one protonymph paratype are deposited in the collection of the Zoological Institute of RAS, St, Petersburg, Russia, other paratypes are deposited in the acarological collection of the Museum of Zoology, University of Tyumen, Tyumen, Russia.
Differential diagnosis. The new species is most similar to Cheletogenes meihuashanense Lin and Liu, 1994 in having the same leg and idiosomal chaetotaxy, and presence of subtriangular dorsal hysterosomal shield with one pair of setae (e1). Female of the new species differs from Ch. meihuashanense in having much larger dorsal idiosomal setae, especially vi which touching or almost touching to each other at their median margins (vs. median margins of setae vi far separated from each other in Ch. meihuashanense); seta d of palpgenu fan-shaped (vs. seta d of palpgenu lanceolate in Ch. meihuashanens); seta d of tibia I fan-shaped (vs. lanceolate in Ch. meihuashanense); setae c2 fan-shaped with evenly rounded anterior margin (vs. setae c2 broadly lanceolate with attenuate tip in Ch. meihuashanense); protegmen smooth (vs. protegmen with U-shaped striation in Ch. meihuashanense).
Etymology. The name of the new species refers to its geographical distribution in Vietnam.
description: Published as part of Khaustov, Alexander A., Salavatulin, Vladimir M., Tsurikov, Sergey M., Thinh, Nguyen Van & Khaustov, Vladimir A., 2024, Free-living predatory cheyletid mites (Acariformes: Cheyletidae) from Cat Tien National Park, Vietnam, pp. 268-295 in Zootaxa 5556 (1) on pages 269-280, DOI: 10.11646/zootaxa.5556.1.20, http://zenodo.org/record/14595308