Neoribates (Neoribates) monodactylus, Ermilov, Sergey G. & Anichkin, Alexander E., 2014

Ermilov, Sergey G. & Anichkin, Alexander E., 2014, Taxonomic study of oribatid mites (Acari, Oribatida) of Bi Dup — Nui Ba National Park (southern Vietnam), Zootaxa 3834 (1), pp. 1-86 : 61-66

Neoribates (Neoribates) monodactylus sp. nov.

( Figures 42–45 )

With characters of the genus Neoribates Berlese, 1914 as summarized by Ermilov & Kaluz (2013).

Diagnosis. Body size 332–348 × 207–232. Prodorsal setae long. Bothridial setae setiform, thickened, weakly dilated in medial part, ciliate. Four pairs of genital setae. Legs monodactylous.

Description. Measurements. Body length 332 (holotype: female), 348 (one paratype: male); body width 207 (holotype), 232 (one paratype).

Integument. Body color brown. Body surface smooth. Pteromorphs with weakly developed radiate wrinkles.

Prodorsum. Rostrum widely rounded. Lamellae distinct, reaching insertions of lamellar setae. Rostral setae (28–36) setiform, ciliate. Lamellar (49–53) and interlamellar (77) setae setiform, sparsely barbed. Bothridial setae (98–102) longest on prodorsum, setiform, thickened, weakly dilated in medial part, ciliate unilaterally. Exobothridial setae absent.

Notogaster. Anterior notogastral margin convex medially. Notogastral setae represented by 10 pairs of alveoli. Four pairs of small sacculi well visible: (Sa and S3 elongate, S1 and S2 oval). Opisthonotal gland openings located laterally to S1.

Gnathosoma. Subcapitulum longer than wide (77 × 69). Subcapitular setae a (12) and h (16) setiform, sparsely barbed; h represented by alveoli. Two pairs of adoral setae (6) setiform, barbed. Palps (45) with setation 0–2–1–3–9(+ω). Solenidion little longer than half of palptarsus length, straight, thickened, dilated distally, attached to eupathidium. Chelicerae (86) with two barbed setae; cha (28) longer than chb (20). Trägårdh’s organ distinct.

Epimeral and lateral podosomal regions. Apodemes (1, 2, sejugal, 3) well visible. Epimeral setal formula: 3–1–3–3. All setae setiform; 1a, 1b, 2a, 3a, 3c barbed, others smooth. Setae 1b, 3b, 3c (12–14) longer than 1a, 2a, 3a (8–10) and 1c, 4a, 4b, 4c (6–8). Setae 3c inserted on pedotecta II; 4c inserted on discidia. Discidia triangular, blunted. Circumpedal carinae distinct.

Anogenital region. Four pairs of genital (8), one pair of aggenital (4), two pairs of anal (12–16) and three pairs of adanal (ad 1, ad 2, 16–20, ad 3, 12) setae setiform, smooth. Adanal setae ad 3 inserted anteriorly to lyrifissures iad.

Legs. Monodactylous; claw of each leg smooth. Formulae of leg setation and solenidia: I (1–5–3–4–20) [1–2–2], II (1–5–3–4–15) [1–1–2], III (2–2–1–3–13) [1–1–0], IV (1–2–2–4–11) [0–0–0]; homologies of setae and solenidia indicated in Table 11 . Setae l’ on femora III, (it) and on tarsi III and a’ on tarsi IV absent.

See Table 2 for explanations.

Type material. Collection data for holotype (female): locality 4 (soil); collection data for one paratype (male): locality 1 (soil).

Type deposition. The holotype is deposited in the collection of the Zoological Institute of the Russian Academy of Sciences, St. Petersburg, Russia; paratype is deposited in the collection of the Tyumen State University Museum of Zoology, Tyumen, Russia.

Etymology. The specific name “ monodactylus ” refers to the monodactylous legs.

Remarks. The subgenus Neoribates (Neoribates) comprises more than 38 species having a cosmopolitan distribution except the Ethiopian and Antarctic regions (data summarized by Subías 2004, updated 2014).

In having the monodactylous legs I, Neoribates (Neoribates) monodactylus sp. nov. is similar to Neoribates (Neoribates) spindleformis Ermilov & Anichkin, 2012 (d) from Vietnam. However, it clearly differs from the latter by the smaller body size (332–348 × 207–232 versus 481–498 × 332–348 in N. (N.) spindleformis ), monodactylous legs II–IV (versus bidactylous in N. (N.) spindleformis ) and setiform bothridial setae (versus spindle-form in N. (N.) spindleformis ).

Figures

FIGURE 42. Neoribates (Neoribates) monodactylus sp. nov., adult: A—dorsal view; B—lateral view of prodorsum and anterior part of notogaster (leg I not illustrated). Scale bar 100 Μm.

FIGURE 43. Neoribates (Neoribates) monodactylus sp. nov., adult: A—ventral view (gnathosoma and legs not illustrated); B—posterior view of notogaster. Scale bar 100 Μm.

FIGURE 44. Neoribates (Neoribates) monodactylus sp. nov., adult: A—pteromorph; B—rostral seta; C—lamellar seta; D—bothridial seta; E—subcapitulum, left half, ventral view; F—palp; G—chelicera; H—pedotectum II, discidium and epimeral setae 3 b, 3 c, 4 c; I—genital plate, left; J—anal plate, left, and adanal setae. Scale bar (A) 50 Μm; scale bar (B, F) 10 Μm; scale bar (C – E, G – J) 20 Μm.

FIGURE 45. Neoribates (Neoribates) monodactylus sp. nov., adult: A—leg I, without trochanter, right, antiaxial view; B—trochanter, femur and genu III, right, antiaxial view; C—leg IV, left, antiaxial view. Scale bar 20 Μm.

Tables

TABLE 11. Leg setation and solenidia of Neoribates (Neoribates) monodactylus sp. nov.

Leg	Trochanter	Femur	Genu	Tibia	Tarsus
I	v'	d, (l), bv'', v''	(l), v', σ	(l), (v), φ1, φ2	(ft), (tc), (it), (p), (u), (a), s, (pv), v', (pl), l'', e, ω1, ω2
II	v'	d, (l), bv'', v''	(l), v', σ	(l), (v), φ	(ft), (tc), (it), (p), (u), (a), s, (pv), ω1, ω2
III	l', v'	d, ev'	l', σ	l', (v), φ	(ft), (tc), (p), (u), (a), s, (pv)
IV	v'	d, ev'	d, l'	d, l', (v)	ft'', (tc), (p), (u), a'', s, (pv)