Trachyoribates insularis, Ermilov & Corpuz-Raros & Naredo & Eusebio, 2022

Ermilov, Sergey G., Corpuz-Raros, Leonila, Naredo, Jeremy C. B. & Eusebio, Orlando L., 2022, New Faunistical Data On Oribatid Mites From The Philippines, With A Description Of A New Species Of The Genus Trachyoribates (Acari, Oribatida, Haplozetidae), Acta Zoologica Academiae Scientiarum Hungaricae 68 (3), pp. 217-229 : 224-228

Trachyoribates insularis sp. n.

( Figs 1–2 )

Diagnosis. Body length: 348–398. Prodorsum, notogaster (except smooth longitudinally elongate median part), pteromorph, epimeral and anogenital (except oval region between genital and anal apertures) regions, and anal plate reticulate; genital plate with several strong longitudinal stria. Rostrum pointed. Rostral and lamellar setae medium-sized, setiform, barbed; Interlamellar seta short, needleform; bothridial seta long, clavate, barbed. Ten pairs of notogastral setal alveoli present. Five pairs of genital setae. Pretarsus of all legs with three claws.

Description of adult. Measurements. Body length: 365 (holotype: male), 348–365 (4 male paratypes), 381–398 (8 female paratypes); notogaster width: 257 (holotype), 257–265 (male paratypes), 282–298 (female paratypes).

Integument. Body color brown. Prodorsum (except smooth basal part), notogaster (except longitudinally elongate median smooth part), pteromorph, epimeral and anogenital (except oval region between genital and anal apertures) regions, and anal plate with reticulate pattern; some cells on pteromorph elongate. Subcapitular mentum and partially subcapitular gena and antiaxial side of legs (except leg III and genu of legs I, II, IV) with small foveolae. Genital plate with several strong longitudinal stria. Lateral prodorsum (between rostral margin and tutorium) granulate.

Prodorsum. Rostrum pointed. Lamella long (3/4 of prodorsum length); cusp with small lateral tooth. Prolamella, sublamella, keel-shaped ridge, and tutorium well visible; tu posteriorly connected to kf. Sublamellar porose area oval (8–12 × 4–6). Rostral (22–28) and lamellar (34–41) setae setiform, barbed; ro inserted at tutorial end, le inserted on the lamellar end, thicker than ro. Interlamellar seta (6–8) needleform. Exobothridial seta not observed. Bothridial seta (49–57) with elongate clavate, barbed head. Lateral tooth of both- rior view. Scale bar 50 μm

ridium well developed. Dorsosejugal porose area poorly visible, oval (16–20 × 4–6), located posterolateral to in. Dorsophragma elongate.

Notogaster. Anterior notogastral margin slightly convex medially. Incision on anterior part of pteromorph (behind bothridium) absent, with poorly visible short, light ventral groove in its place. Ten pairs of setal alveoli present. Four pairs of sacculi with small opening and drop-like chamber. Distance S1–S1 shorter than S2–S2. Opisthonotal gland opening and lyrifissures ia, im, ip well visible; ih and ips not observed.

Gnathosoma . Subcapitulum size: 90–94 × 69–73. Subcapitular (a, h: 12–14; m, 16–18) and adoral (6–8) setae setiform, barbed. Palp (length: 57–61) with setation 0-2-1-3-9(+ω). Postpalpal seta (4) spiniform, roughened. Chelicera (length: 102–106) with two setiform, barbed setae (cha: 28–30; chb: 18–20).

Epimeral and lateral podosomal regions. Epimeral setal formula: 3-1-3-3. Epimeral setae 1b, 3b, 3c (14–16) and 3a, 4c (10–12) setiform, slightly barbed; 1a, 1c, 2a, 4a, 4b (6–8) needleform. Discidium triangular. Humeral porose area Ah elongate oval; Am not observed. Circumpedal carina long, extended into pedotectum II as ventrolateral ridge.

Anogenital region. Genital seta g 1 (10–12) setiform, slightly barbed; genital seta g 2 – g 5, aggenital, anal and adanal setae (6–8) setae needleform. Adanal lyrifissure distinct. Adanal setae ad 1 and ad 2 lateral (rarely ad 1 posterior), ad 3 anterior to anal aperture. Marginal porose area represented by several rounded and oval parts. Ovipositor elongate (147–155 × 36–41), blade (57–61) shorter than length of distal section (beyond middle fold; 90–94); each of the three blades with four smooth setae, ψ 1 ≈ τ 1 (32–30) setiform, ψ 2 ≈ τ a ≈ τ b ≈ τ c (8) thinly thornlike; all coronal setae not observed.

Legs. Heterotridactylous, all claws barbed on dorsal side, lateral claws with small tooth ventrodistally. Dorsoparaxial porose area well visible on femora I-IV and on trochanters III, IV. Ventroproximal porose area on all tarsi and ventrodistal porose area on all tibiae not observed. Tibia II with broad process ventrodistally. 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. Famulus of tarsus I short, straight, slightly swollen distally, located posterior to solenidion ω 2. Solenidion ω 1 on tarsus I, ω

1

and ω

2

on tarsus II, σ on genu III bacilliform, other solenidia setiform.

Material examined. Holotype (male) and nine paratypes (three males and six females): locality 14; two paratypes (one male and one female): locality 13; one paratype (one female): locality 3.

Type deposition. The holotype is deposited in the collection of the Senckenberg Institute, Görlitz, Germany; twelve paratypes are deposited in the collection of the Tyumen State University Museum of Zoology , Tyumen, Russia . All specimens are preserved in 70% solution of ethanol with a drop of glycerol.

Etymology. The specific name insularis refers to the insular place of origin. Note: Roman letters refer to setae, Greek letters to solenidia (except ε = famulus); single quotation mark (’) designates setae on the anterior and double quotation mark (”) setae on the posterior side of a given leg segment; parentheses refer to a pair of setae.

Remarks. Trachyoribates insularis sp. n. is morphologically most similar to Trachyoribates filipinus ( Corpuz-Raros, 1979) (see also CORPUZ-RAROS 1991) from the Philippines in having all legs with three claws, short interlamellar seta and a pointed rostrum. However, the new species differs from the latter by the presence (versus absence) of smooth longitudinally elongate median part of the notogaster and striate genital plate, and the absence (versus presence) of notogastral setae (setal alveoli versus short setae).

Figures

Fig. 1. Trachyoribates insularis sp. n., adult: A = dorsal view (legs not shown); B = ventral view (gnathosoma and legs not shown); C = right lateral view (legs not shown); D = poste-

Fig. 2. Trachyoribates insularis sp. n., adult: A = subcapitulum, ventral view; B = palp, left, paraxial view; C = chelicera, left, paraxial view; D = leg I, right, antiaxial view; E = leg II, without tarsus, right, antiaxial view; F = leg III, without tarsus, left, antiaxial view; G = leg IV, left, antiaxial view. Scale bars 20 μm (A, C–G), 10 μm (B)