Perscheloribates paratranslamellatus, Ermilov & Rybalov, 2014

Ermilov, Sergey G. & Rybalov, Leonid B., 2014, Ethiopian oribatid mites (Acari: Oribatida) from the Joint Russian-Ethiopian Biological Expedition (2012), with description of a new species, African Invertebrates 55 (1), pp. 27-37 : 28-33

Perscheloribates paratranslamellatus sp. n.

Figs 1–2

Etymology: From the Latin prefix para (near) referring to the the similarity between the new species and the species Perscheloribates translamellatus (Pérez-Íñigo & Baggio, 1991) .

Diagnosis: body size 481–531× 298–348; rostrum rounded; rudimentary translamellar line; prolamellar lines absent; prodorsal setae setiform, barbed; sensilli spindle-form, ciliate; exobothridial setae short; one pair of notogastral setae p 1 present; sacculi Sa, S1 with elongate openings, S2, S3 with rounded openings; ventral setae setiform, slightly barbed, and with little difference in length; leg claws serrate on dorsal side.

Description:

Measurements. Body (length × width): 481 × 298 (holotype ♂); 481–531 × 298–348 (paratypes: 1♂ 4♀).

Integument. Body brown and light brown. Dorsal and ventral surfaces of body smooth, lateral surfaces weakly microgranulate.

Prodorsum ( Figs 1A, 1B, 1D ; 2A, 2B ). Rostrum slightly protruding, rounded. Lamellae located dorsolaterally, as long as half of prodorsum (in lateral view), without cusps. Translamellar line (tr) rudimental, at tips of lamellae. Prolamellar lines absent. Sublamellar lines distinct, long. Sublamellar porose areas (Al) very small, rounded (2–4). Keel-shaped chitinised ridges (kf) distinct. Rostral (ro, 61–69), lamellar (le, 90–102) and interlamellar (in, 114–127) setae setiform, barbed. Sensilli (ss, 110–118) spindle-form (with long stalk, elongated lanceolate head and well developed thin apex), with numerous cilia. Exobothridial setae (ex, 4–6) short, thin, smooth.

Notogaster ( Figs 1A, 1C ).Anterior notogastral margin convex medially. Dorsophragmata (D) of medium size, widely rounded. Nine pairs of notogastral setae represented by alveoli; only one pair of thin, smooth setae developed (p 1, 8–10). Four pairs of sacculi present: Sa, S1 with elongate openings, S2, S3 with small, rounded openings. Circumgastric band of muscle sigillae distinct. Opisthonotal gland openings (gla) and lyrifissures developed in typical arrangement for genus.

Anogenital region ( Figs 1B, 1C ). Three pairs of adanal (ad 1 – ad 3, 16–20), one pair of aggenital (ag, 16–20), two pairs of anal (an 1, an 2, 12–16) and four pairs of genital (g 1 – g 4, 16–20) setae setiform, slightly barbed. Lyrifissures iad in para-anal position, located nearly to anal aperture.

Epimeral and lateral podosomal regions ( Figs 1B, 1D ). Apodemes 1, 2, 3 and sejugal apodemes distinct. Epimeral setal formula: 3–1–3–3. Setae (16–24) setiform, thin, slightly barbed; medial setae little shorter than others. Pedotecta I (Pd I) large, concave; pedotecta II (Pd II) rounded anteriorly. Discidia (dis) triangular, rounded. Circumpedal carina (cp) distinct.

Gnathosoma ( Figs 2C–2E ). Subcapitulum longer than wide: 118–123×82. Subcapitular setae setiform, barbed; h (28–32) longer than a, m (both 20). Lateral lips with two pairs of setiform, barbed adoral setae (or 1, or 2, 10–12). Palps (length 69–73) with setation 0–2–1–3–9(+ω). Solenidion coupled with eupathidium acm.All setae (except some on tarsi) weakly barbed. Chelicerae (length 118–123) with two setiform, barbed cheliceral setae; cha (36–41) longer than chb (24–28).

Legs ( Fig. 2F ). Claw of each leg with several minute barbs on dorsally side. Formulae of leg setation and solenidia: I (1–5–2–4–19) [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 2. Almost all setae (except p) barbed or with short cilia. Famulus (e) short, straight, indistinctly dilated apically, blunted. Solenidia ω 1 on tarsi I, ω 1 and ω 2 on tarsi II, σ on genua III short, thickened, blunt-ended; other solenidia longer, thinner, setiform.

Holotype: ♂ ETHIOPIA: Et-12–10. Preserved in ethanol ( ZISP).

Paratypes: 1♂ 4♀ ETHIOPIA: Et-12–10. Preserved in ethanol (1♂ 2♀ SZMN; 2♀ PC) .

Distribution: At present, this species is only known from the type locality.

Remarks: In having one pair of notogastral setae p 1 (other setae represented by alveoli), spindle-form and ciliate sensilli, and rounded rostrum, P. paratranslamellatus sp. n. is similar to P. translamellatus from Peru (Pérez-Íñigo & Baggio 1991); however, it differs from the latter by larger body size (481–531 ×298–348 versus 324–360 ×196–216), a rudimental translamellar line running nearly to lamellae (translamella complete in P. translamellatus ), absence of prolamellar lines (present, not reaching insertions of rostral setae in P. translamellatus ), longer setae p 1 (minute in P. translamellatus ) and elongate openings of sacculi Sa, S1 (rounded in P. translamellatus ).

From the Ethiopian species, Perscheloribates minutus ( Pletzen 1965; Corpuz-Raros 1980) is the closest morphologically to P. paratranslamellatus sp. n.; however, it differs from P. minutus in that it has a larger body size (481–531 ×298–348 versus 343–394 × 216–303 in P. minutus ), absence of prolamellar lines (present in P. minutus ), and development of a single pair of notogastral setae p 1 (versus p 1 – p 3 developed in P. minutus ).

Figures

Fig. 1. Perscheloribates paratranslamellatus sp. n.: (A) dorsal view (legs not shown); (B) ventral view (gnathosoma and legs not shown); lateral view of (C) body posterior; (D) body anterior. Scale bars A, B=100 μm; C, D=50 μm.

Fig. 2. Perscheloribates paratranslamellatus sp. n.: (A) rostral seta; (B) sensillus; (C) subcapitulum, right half; (D) palptarsus; (E) anterior part of chelicera; (F) tarsus and anterior part of tibia, leg I, left, antiaxial view. Scale bars A–C, E=20 μm; D=10 μm; F=50 μm.