Eustigmaeus vietnamiensis, Khaustov & Tsurikov, 2018

Khaustov, Alexander A. & Tsurikov, Sergey M., 2018, A new species of Eustigmaeus (Acari: Prostigmata: Stigmaeidae) from Vietnam, Persian Journal of Acarology 7 (3), pp. 235-244 : 236-239

publication ID	https://doi.org/ 10.22073/pja.v7i3.39903
publication LSID	lsid:zoobank.org:pub:E0F452E7-D407-4F11-9B83-92668FF57DE9
persistent identifier	https://treatment.plazi.org/id/B5E54A13-C39C-4F5F-8487-F18F24D1D76D
taxon LSID	lsid:zoobank.org:act:B5E54A13-C39C-4F5F-8487-F18F24D1D76D
treatment provided by	Felipe
scientific name	Eustigmaeus vietnamiensis
status	sp. nov.

Treatment

Eustigmaeus vietnamiensis sp. nov. ( Figs. 1–5 View Figure 1 View Figure 2 View Figure 3 View Figure 4 View Figure 5 )

Description

FEMALE. Idiosoma oval in outline. Length of idiosoma 260, width 190.

Idiosomal dorsum ( Figs. 1A View Figure 1 , 4 View Figure 4 , 5A–D View Figure 5 ) – Idiosoma completely covered by two large plates ( Fig. 4 View Figure 4 ). Plates with large round dimples of similar size without punctations. Diameter of eyes 12. Dorsal setae brush-like ( Figs. 5A–D View Figure 5 ). A very weak subcuticular reticulate pattern visible in central parts of dorsal plates. Setae h 1 and h 2 situated ventrally. Setae h 2 only slightly thickened, not brushlike distally. Length of dorsal setae: vi 27, ve 32, sci 28, sce 25, c 1 28, c 2 20, d 1 30, d 2 26, e 1 29, e 2 28, f 1 28, h 1 23, h 2 14.

Idiosomal venter ( Figs 1B View Figure 1 , 5E, F View Figure 5 ) – Callosities absent. Endopodal plates separated medially, smooth. Humeral plates triangular, with round dimples as on dorsal plates. With two pairs of simple aggenital, and three pairs of simple pseudanal setae. All ventral setae smooth and pointed. Length of ventral setae: 1 a 17, 1 b 17, 1 c 14, 2 b 15, 2 c 13, 3 a 18, 3 b 16, 3 c 13, 4 a 17, 4 b 18, 4 c 17, ag 1 13, ag 2 11, ps 1 16, ps 2 14, ps 3 11.

Gnathosoma ( Figs 2A View Figure 2 , 5E View Figure 5 ) – Chelicerae mostly smooth dorsally, with several transverse lines in posterior half. Palpal segments not reticulated. Tibial claw well-developed. Setae l’ on palpal tibia spine–like. Setae on palpal femur and genu weakly barbed, other palpal setae smooth. Palpal supracoxal setae (ep) spine-like. Number of setae on palpal segments: Tr 0, Fe 3 (d, l’, v”), Ge 2 (d, l”), Ti 3 (d, l’, l”), Ta 8(1) (fused eupathidia ul’ξ, ul” ξ, sul ξ, eupathidion acm ξ, ba, bp, lp, 1 solenidion ω). Rostrum of subcapitulum ( Fig. 5E View Figure 5 ) relatively short and wide. All subcapitular setae smooth, setae or 1 and or 2 slightly thickened, curved and blunt-ended; other subcapitular setae simple, pointed. Basal part of subcapitulum without distinct reticulation, with several weak longitudinal lines in posterior half ( Fig. 5E View Figure 5 ). Length of subcapitular setae: m 17, n 16, or 1 8, or 2 9.

Legs ( Figs 2B, C View Figure 2 , 3 View Figure 3 ) – Empodial raylets weakly capitate. Length of legs: I 115, II 105, III 110,

IV 115. Leg I ( Fig. 2B View Figure 2 ). Coxae I posterodorsally with spine-like leg supracoxal setae (el). Leg

chaetotaxy: Tr 1 (v’), Fe 6 (d, l’, l”, v’, v”, bv”), Ge 4 (d, l’, l ”, k), Ti 5(2) (dξ, l’, l”, v’, v”, φ, φp), T a 13(1) (p’ξ, p”ξ, tc’ξ, tc”, ft’ξ, ft”ξ, u’, u”, a’, a”, pl’, pl”, vs, ω). Setae d on tibia and (p), (tc), (ft) on tarsus are eupathidia. All setae (except eupathidia) barbed. Setae d on femur and genu brushlike with hyaline sheaths; setae l” of genu and l’ of tibia thickened, with hyaline sheaths distally; setae l” of femur and l’ of genu blunt-tipped, other setae (except eupathidia) pointed. Seta k 8. Solenidion ω 13, finger-shaped; solenidia φ 5 and φp 12 baculiform. Leg II ( Fig. 2C View Figure 2 ). Leg chaetotaxy: Tr 1 (v’), Fe 5 (d, l’, l”, v’, bv”), Ge 4 (d, l’, l”, k), Ti 5(1) (dξ, l’, l”, v’, v”, φ), Ta 9(1) (p’ξ, tc’ξ, tc”, u’, u”, a’, a”, pl’, vs, ω). Setae d on tibia, p’ and tc’ on tarsus represented by eupathidia. All setae (except eupathidia) barbed. Setae d, l” on femur and genu brush-like with hyaline sheaths; seta l’ of tibia thickened, with hyaline sheath distally; seta l’ of genu blunt-tipped, other setae (except eupathidia) pointed. Solenidion ω 12 finger-shaped; solenidion φp 9 baculiform. Seta ĸ 5. Leg III ( Fig. 3A View Figure 3 ). Leg setation: Tr 1 (v’), Fe 3 (d, l’, ev’), Ge 1 (d), Ti 5(1) (d, l’, l”, v’, v”, φ), Ta 7 (1) (tc’, tc”, u’, u”, a’, a”, vs, ω). Solenidioa ω 6 and φp 9 baculiform. All setae barbed. Setae l’ of trochanter, d, l’ of femur, d of genu, d and l’ of tibia distinctly thickened, brush-like with hyaline sheaths, other setae pointed. Leg IV ( Fig. 3B View Figure 3 ). Leg setation: Tr 1 (v’), Fe 2 (d, ev’), Ge 1 (d), Ti 5(1) (d, l’, l”, v’, v”, φ), Ta 7(1) (tc’, tc”, u’, u”, a’, a”, vs, ω). Solenidia ω 4 and φ 8 baculiform. Setae d of femur, d of genu, d and l’ of tibia distinctly thickened, brush-like with hyaline sheaths, other leg setae pointed. Setae (tc), (u) and a” of tarsus smooth, other setae barbed.

Type material

Female holotype, slide No. ZISP T-St-001, VIETNAM, Cat Tien National Park, on the bark of fig tree ( Ficus sp.), 16 January 2015, coll. S. Tsurikov. Paratypes: three females, same data, slides ZISP T-St-oo2, ST160115, ST160115 /1.

Type deposition

The holotype and one paratype are deposited in the in the mite collection of the Zoological Institute of Russian Academy of Sciences, Saint Petersburg, Russia , two paratypes are deposited in the mite collection of the Tyumen State University Museum of Zoology , Tyumen, Russia .

Etymology The name of the new species is refers to distribution in Vietnam.

Differential diagnosis

The new species is most similar to E. clavigerus ( Wood, 1966) , described from the New Zealand ( Wood 1966; Fan and Zhang 2005), and E. barrioni Rimando & Corpuz-Raros, 1997 , described from the Philippines ( Rimando and Corpuz-Raros 1997), by the presence of eyes, absence of callosities, not fused endopodal plates medially, presence of two pairs of aggenital setae and brush-like dorsal idiosomal setae. The new species can be distinguished from both species by very weak subcuticular reticulation pattern visible only in central parts of dorsal plates (vs. dorsal plates strongly reticulated in E. clavigerus and E. barrioni ), and dorsal setae densely barbed, strongly clavate, with rounded tips, distal barbs rounded and with hyaline sheaths (vs. dorsal setae not so densely barbed, weakly clavate, with attenuated tips, distal barbs attenuated in E. clavigerus and E. barrioni ). From E. clavigerus it differs by the endopodal plates smooth (vs. endopodal plates reticulated in E. clavigerus ), distinctly shorter solenidion on tarsus I (13) (vs. 17-20 in E. clavigerus ), and seta d on palpfemur pointed, weakly barbed (vs. seta d of palpfemur blunt-ended, with several strong subapical barbs in E. clavigerus ). From E. barrioni it also can be distinguished by smooth dimples on dorsal idiosomal plates (vs. with punctations in E. barrioni ), and by distinctly widened distally, strongly clavate setae c 2 (vs. setae c 2 baculiform, not clavate in E. barrioni ).