Scheloribates (Scheloribates) daoensis, Ermilov & Starý, 2017

Ermilov, Sergey G. & Starý, Josef, 2017, A new species of Scheloribates (Acari, Oribatida, Scheloribatidae) from Vietnam, with key to the striolatus-group, Ecologica Montenegrina 10, pp. 14-21 : 15-19

Scheloribates (Scheloribates) daoensis sp. nov.

( Figs 1–11 )

Diagnosis. Body size: 465–531 × 265–348. Translamellar line represented by two short, rudimentary parts. Prolamellae complete. Rostral, lamellar and interlamellar setae long, setiform, barbed, ro shortest, in longest. Bothridial setae spindle-form, barbed unilaterally, apex longer than heads. Notogastral setae minute. Distance between pair of sacculi S1–S1 longer than that of S2–S2. Epimeral and anogenital setae thin, slightly barbed. Lateral leg claws each with small tooth ventrodistally. Leg tarsi I with 19 setae (v’ present, l” absent).

Description. Measurements. Body of medium size, one female larger than two males. Body length: 531 (holotype, female), 465, 481 (two paratypes, two males); notogastral width: 348 (holotype), 265, 298 (two paratypes).

Integument ( Figs 1–4 ). Body color light brown. Body surface microporose (visible under high magnification, × 1000). Lateral parts of prodorsum microgranulate. Notogaster, ventral parts of pedotecta I and lateral sides of anal plates and ano-adanal region heavily striate.

Prodorsum ( Figs 1, 2 , 4 ). Rostrum narrowly rounded. Lamellae (lam) located dorso-laterally, as long as half of prodorsum (measured in lateral view). Prolamellae (plam) complete, lineate, curving backwards distally. Sublamellae (slam) thin, little shorter than lamellae. Translamellar line (tlam) represented by two rudimentary parts (well separated medially) near lamellae. Sublamellar porose areas (Al) oval (8–10 × 6). Rostral (ro, 65–69), lamellar (le, 90–102) and interlamellar (in, 110–123) setae setiform, barbed. Bothridial setae (bs, 118–131) spindle-form, barbed unilaterally, stalks longest, heads shortest, well dilated, elongate oval, apex thin, setiform. Anterocentral transverse ridge (r), lateral keel-shaped ridges (kf) and lateral prodorsal ridges (prl) present. Exobothridial setae (ex, 22–24) thin, indistinctly barbed. Sejugal porose areas not visible.

Notogaster ( Figs 1, 3 , 4 ). Anterior notogastral margin convex medially. Dorsophragmata (D) semioval. Ten pairs of notogastral setae present, all minute (2), visible only under high magnification (× 1000). Four pairs of sacculi (Sa, S1, S2, S3) with small openings and channels, distance S1–S1 longer than S2–S2. Setae lp inserted medially to S1. Lyrifissures (ia, im, ip, ih, ips) and opisthonotal gland openings (gla) clearly visible.

Gnathosoma ( Figs 5–7 ). Subcapitulum longer than wide (98–123 × 73–82). Subcapitular setae setiform, barbed, h (30–32) longer and thicker than a (20–22), setae m shortest (14–16) and thinnest. Two pairs of adoral setae (or 1, or 2, 10–12) setiform, heavily ciliate. Palps (length 61–73) with setation 0–2–1–3– 9(+ω). Solenidia slightly dilated anterodorsally. Postpalpal setae (4) spiniform, smooth. Chelicerae (length 98–123) with two barbed setae, cha (32–36) longer than chb (20–24). Trägårdh’s (Tg) organ elongate triangular.

Epimeral and lateral podosomal regions ( Figs 2 , 4 ). Epimeral setal formula: 3–1–3–3. Setae thin, slightly barbed, 1a, 1c, 2a and 3a (12–16) shorter than other setae (24–32). Setae 1c inserted ventrolaterally on pedotecta I. Pedotecta I (Pd I) and II (Pd II) represented by small laminae, Pd II trapezoid. Discidia (dis) slightly developed, elongate triangular. Circumpedal carinae (cp) very short.

Anogenital region ( Figs 2 , 4 ). Four pairs of genital (g 1 – g 4), one pair of aggenital (ag), two pairs of anal (an 1, an 2) and three pairs of adanal (ad 1 – ad 3) setae similar in length (12–16), setiform, slightly barbed. Adanal lyrifissures (iad) located close and parallel to anal plates. Preanal organ (p.o.) trapezoid in ventral view.

Legs ( Figs 8–11 ). Median claw thicker than laterals, all serrate on dorsal side; lateral claws each with small tooth ventrodistally. Dorso-paraxial porose areas (p.a.) on femora I–IV and trochanters III, IV and ventral porose areas in basal parts of tarsi and distal parts of tibiae well visible. Formulas of leg setation and solenidia: I (1–5–3–4–19) [1–2–2], II (1–5–2–4–15) [1–1–2], III (2–3–1–3–15) [1–1–0], IV (1–2–2–3–12) [0–1–0]; homology of setae and solenidia indicated in Table 1 . Solenidia ω 1 on tarsi I, ω 1 and ω 2 on tarsi II and σ on genua III thickened, blunt-ended, other solenidia longer, setiform. Famuli short, straight, slightly dilated and truncated distally, inserted posterior to solenidia ω 2.

Type deposition. The holotype is deposited in the collection of the Senckenberg Institute , Görlitz, Germany ; two paratypes are deposited in the collection of the Tyumen State University Museum of Zoology , Tyumen, Russia .

Etymology. The specific name daoensis refers to the second part of the name of the Tam Dao National Park, Northern Vietnam, where the new species was collected.

Remarks. Scheloribates daoensis sp. nov. is morphologically most similar to S. striolatus Balogh, 1960 from Madagascar in having striate notogaster, spindle-form bothridial setae and rudimentary parts of translamellar line. However, the new species differs from the latter by the smaller body size (465–531 × 265–348 vs. 700 × 498), bothridial setae with apex longer head (vs. apex shorter than head), very short circumpedal carinae (vs. long) and distance between sacculi S1–S1 longer than S2–S2 (vs. shorter).

Figures

Figures 1–3. Scheloribates (Scheloribates) daoensis sp. nov.: 1 — dorsal view; 2 — ventral view (gnathosoma and legs not shown); 3 — posterior view (part of right half not shown); Scale bar 100 μm.

Figures 4–7. Scheloribates (Scheloribates) daoensis sp. nov.: 4 — lateral view (gnathosoma and legs not shown); 5 — subcapitulum, ventral view; 6 — palp, right, antiaxial view; 7 — chelicera, right, antiaxial view. Scale bar 100 μm (4), 20 μm (5, 7; 6).

Figures 8–11. Scheloribates (Scheloribates) daoensis sp. nov.: 8 — leg I, right, antiaxial view; 9 — trochanter, femur and genu of leg II, right, antiaxial view; 10 — trochanter, femur and genu of leg III, left, antiaxial view; 11 — leg IV, left, antiaxial view. Scale bar 50 μm.