Tectodamaeus heterotrichus, 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 : 15-20

Tectodamaeus heterotrichus sp. nov.

( Figures 7–10 )

With characters of the genus Tectodamaeus Aoki, 1984 as summarized by Aoki (1984 a).

Diagnosis. Body size 481–614 × 398–448. Rostral and lamellar setae setiform, slightly barbed. Interlamellar setae short, weakly thickened, smooth. Bothridial setae long, thick, weakly dilated in medial part, densely barbed. Spinae adnatae absent. Dorsal notogastral setae thorn-like, slightly barbed, differ in length: h 1, h 3> c 1, c 2> lp> la, lm, h 2. Parastigmatic tubercles Sa triangular, Sp rectangular. Epimeral tubercles E2a, E2p, Va and Vp present. Leg tibiae with nine setae.

Description. Measurements. Body length 531 (holotype: female), 481–614 (three paratypes: one female and two males); body width 415 (holotype), 398–448 (three paratypes).

Integument. Body color brown to black. Body covered with tuberculate cerotegument (diameter tubercles up to 4). Body surface smooth.

Prodorsum. Rostrum narrowly rounded. Rostral (82–90) and lamellar (139–155) setae setiform, slightly barbed. Interlamellar setae short (16–20), weakly thickened, smooth, covered by several granules on their surface. Bothridial setae longest setae on prodorsum (217–233), thick, weakly dilated in medial part, densely barbed. Exobothridial setae (32–36) thin, slightly barbed. Three pairs of prodorsal tubercles (Da, Ba, Bp) developed, triangular, round-ended.

Notogaster. Oval. Anterior notogastral margin convex medially. Spinae adnatae absent. Dorsal notogastral setae inserted in 2 sub-parallel rows, thorn-like, slightly barbed, differ in length: h 1, h 3 (86–98) longer than c 1, c 2 (53–61), lp (32–41), la, lm, h 2 (20–28). Posterior setae p 1– p 3 (65–69) setiform, thickened, slightly barbed.

Gnathosoma. Subcapitulum longer than wide (143–147 × 86–90). Subcapitular setae setiform; h (41) barbed, longer than a and m (both 32), slightly barbed. Two pairs of adoral setae (12) setiform, smooth. Palps (114–118) with setation 0–2–1–3–9(+ω). Solenidion shorter than half of palptarsus length, straight, thickened, blunt-ended, not attached to eupathidium. Chelicerae (98–106) with two setae, having flagellate tip; cha (61–65) barbed, longer than chb (36–41) with long cilia in middle part. Trägårdh’s organ distinct.

Epimeral and lateral podosomal regions. Apodemes (1, 2, sejugal) weakly visible. Parastigmatic tubercles large: Sa elongate, triangular, blunt-ended; Sp rectangular. Epimeral tubercles E2a and E2p small, broadly triangular in ventral view. Ventrosejugal tubercles Va and Vp strongly developed, triangular to broadly rounded. Epimeral formula: 3–1–3–4. Setae setiform, slightly barbed; 1b, 3b (61–73) longer than 3c, 4a, 4b, 4c, 4d (45–53) and 1a, 1c, 2a, 3a (28). Setae 3b and 4a inserted on Vp. Discidia (dis) well developed, triangular, blunt-ended.

Anogenital region. Six pairs of genital (g 1, 53; g 2–g6, 32–36) and two pairs of anal setae (an 1, an 2, 32–36) setiform, smooth. One pair of aggenital (ag) and three pairs of adanal (ad 1– ad 3) similar in length (41–45), setiform, slightly barbed. Adanal lyrifissures (iad) located anteriorly to ad 3. Ovipositor typical for Damaeidae (Ermilov 2010) , short (89 × 69); length of lobes 28, length of cylindrical distal part 61. Each lobes with four setae; all thornlike, smooth, similar in length: ψ1 ≈ τ1 ≈ ψ2 ≈ τ a ≈ τ b ≈ τ c (16). Six coronal setae short (6), thin, smooth.

Legs. Monodactylous; claws smooth. Lengths of legs and their segments are given in Table 3. Formulae of leg setation and solenidia: I (1–7–3–9–21) [1–2–2], II (1–7–4–9–18) [1–1–2], III (2–4–3–9–18) [1–1–0], IV (1–4–2–9–15) [0–1–0]; homologies of setae and solenidia indicated in Table 4 .

Leg Trochanter Femur Genu Tibia Tarsus

I v' d, (l), (v), v'', bv'' d σ, l'', v' d, l'', (v 1), v 2 ', (v 3), (v 4), (ft), (tc), (it), (p), (u), (a), s, (pv), (v 1), v 2 ',

φ1, φ2 (pl), e, ω1, ω2

II v' d, (l), (v), v'', bv'' d σ, (l), v' d, l'', (v 1), v 2 ', (v 3), (v 4), φ (ft), (tc), (it), (p), (u), (a), s, (pv), (v 1), v 2 ',

ω1, ω2

III l', v' d, l', v', ev' d σ, l', v' d, (v 1), (v 2), (v 3), (v 4), φ (ft), (tc), (it), (p), (u), (a), s, (pv), (v 1), v 2 ' IV v' d, l', v', ev' d, v' d, (v 1), (v 2), (v 3), (v 4), φ ft'', (tc), (p), (u), (a), s, (pv), (v 1), v 2 '

See Table 2 for explanations.

Type material. Collection data for holotype (female): locality 6 (litter); collection data for three paratypes (one female and two males): locality 6 (litter).

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

Etymology. The specific name “ heterotrichus ” refers to the heterotrichy of notogastral setae.

Remarks. The genus Tectodmaeus comprises about 20 species (see different opinions on classification, for example: Wang & Cui 1994; Subías 2004), which are distributed in the Palaearctic and Oriental regions (data summarized by Subías 2004, updated 2014).

In having the characteristic morphology of ventral side of the body, absence of spinae adnatae and the presence of notogastral heterotrichy, Tectodamaeus heterotrichus sp. nov. is most similar to Tectodamaeus brevisetus ( Wang, 1994 in Wang & Cui 1994) from southern China. However, it clearly differs from the latter by the smaller body size (481–614 × 398–448 versus 733–766 × 479–499 in T. brevisetus ), rectangular parastigmatic tubercles (versus thorn-like in T. brevisetus ), more clear heterotrichy of notogastral setae (h 1, h 3> c 1, c 2> lp> la, lm, h 2 versus c 2> c 1, la, la, lm, lp, h 3> h 2> h 1 in T. brevisetus ) and nine setae on all leg tibiae (versus I(7)–II(6)–III(5)–IV(5) in T. brevisetus ).

Figures

FIGURE 7. Tectodamaeus heterotrichus sp. nov., adult: A—dorsal view (legs not illustrated); B—lateral view of prodorsum and anterior part of notogaster (gnathosoma and legs I, II, III except trochanter III not illustrated). Scale bar 200 Μm.

FIGURE 8. Tectodamaeus heterotrichus sp. nov., adult: A—ventral view (gnathosoma and legs not illustrated); B—posterior part of body, lateral view. Scale bar 200 Μm.

FIGURE 9. Tectodamaeus heterotrichus sp. nov., adult: A—part of prodorsal region with interlamellar and exobothridial setae, bothridium, tubercles Da, Ba, Bp; B—bothridial seta; C—notogastral seta lm; D—notogastral seta lp; E—notogastral seta h 1; F—notogastral seta p 3; G—subcapitulum, left half, ventral view; H—palp; I—chelicera; J—epimeral tubercles E 2 a, E 2 p and epimeral seta 1 b; K—epimeral tubercles Va, Vp and epimeral setae 3 b, 4 a; L—genital plate, right; M—anal plate, right, and adanal seta ad 3. Scale bar (A, B, J – M) 50 Μm; scale bar (C – I) 20 Μm.

FIGURE 10. Tectodamaeus heterotrichus sp. nov., adult: A—leg I, without trochanter, right, antiaxial view; B—leg IV, right, antiaxial view; C—genu III, dorsal view. Scale bar 100 Μm.

Tables

TABLE 4. Leg setation and solenidia of Tectodamaeus heterotrichus sp. nov.

Legs Trochanter Femur	Genu	Tibia	Tarsus	All
I 33 481	132	365	398	1409
II 33 365	83	232	348	1061
III 116 365	116	348	348	1293
IV 116 581	166	514	415	1792
See Table 2 for explanations.