Scheloribates (Topobates) tredecim, Ermilov & Rybalov & Kuzmicheva, 2024

Ermilov, Sergey G., Rybalov, Leonid B. & Kuzmicheva, Evgeniya A., 2024, New Scheloribates (Acari, Oribatida, Scheloribatidae) from Ethiopia, Zootaxa 5492 (2), pp. 176-190 : 186-189

Scheloribates (Topobates) tredecim sp. nov.

( Figs 7 , 8 )

Material. Holotype (female) and seven paratypes (five males and two females): Southeastern Ethiopia, Oromia Region, Bale Zone, Bale Mountains National Park , 6°43′18.1″N, 39°44′12.1″E, 2570 m a.s.l., Harenna Forest , litter in bamboo belt (vegetation represented by dense bamboo thickets of Oldeania alpina , the African alpine bamboo, Hagenia abyssinica, Myrsine melanophloeos, and Schefflera volkensii trees accompany bamboo), 15.XI.2014 (E.A. Kuzmicheva).

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

Diagnosis. Body length: 390–450. Notogaster distinctly elongate. Rostrum protruding, rounded. Prolamella and translamella absent. Rostral, lamellar and interlamellar setae long, setiform, barbed; in ˃(=) le ˃ ro; bothridial seta long, lanceolate, barbed. Thirteen pairs of notogastral setae short, needleform. Four pairs of sacculi. Circumpedal carina long. Anal and adanal setae medium-sized, setiform, thin, roughened. Ventrobasal tubercle of leg tibiae I, II well observable; femur II broadly rounded ventrodistally; tarsus I with 19 setae (l” absent; v’ present). Tridactylous.

Description of adult. Measurements. Body length: 420 (holotype), 390–420 (male paratypes), 420–450 (female paratypes); body width (level of pteromorph): 240 (holotype), 225–240 (male paratypes), 255 (female paratypes); width of ventral plate: 225 (holotype), 195–225 (male paratypes), 225–240 (female paratypes).

Integument. Body color light brown. Surface densely microfoveolate (visible only under high magnification in dissected specimens; ×1000); podosomal region and lateral part of prodorsum partially with dense microgranulate cerotegument.

Prodorsum ( Figs 7A, C ). Rostrum protruding, rounded. Lamella about 1/2 length of prodorsum; prolamella and translamella absent; sublamella and lateral keel-shaped ridge distinct; sublamellar porose area (7) rounded. Rostral (71–75), lamellar (67–71) and interlamellar (75–79) setae setiform, barbed; bothridial seta (56–64) with lanceolate, barbed head, directed posterolaterad; bothridial stalk and head similar in length or stalk slightly longer than head; exobothridial seta (30–34) setiform, thin, roughened. Dorsosejugal porose area oval, poorly visible.

Notogaster ( Figs 7A, C ). Anterior notogastral margin convex medially. Notogaster distinctly elongate. Pteromorph medium-sized, broadly rounded laterally, its anterior margin straight (perpendicular to longitudinal axis of body in dorsal aspect). Thirteen pairs of notogastral setae (6) needleform. Four pairs of saccules with small opening and drop-like channel. Opisthonotal gland opening and all lyrifissures distinct.

Gnathosoma ( Figs 8A–C ). Subcapitulum size: 105–112 × 75–82; subcapitular setae (a: 19–22; m: 15–19; h: 26–30) setiform, roughened; m thinner than a and h; both adoral setae (13–15) setiform, barbed. Palp length: 60–64; postpalpal seta (7) spiniform, roughened. Chelicera length: 112–116; setae (cha: 34–37; chb: 22–24) setiform, barbed.

Epimeral and lateral podosomal regions ( Figs 7B, C ). Epimeral formula: 3–1–3–3; all setae (1a, 2a, 3a: 11–13; 1b, 3b, 3c: 26–28; others: 19–22) setiform, thin, roughened. Humeral porose areas Am and Ah poorly visible, elongate oval. Pedotectum II rounded laterally in ventral aspect. Discidium broadly rounded. Circumpedal carina long, directed to pedotectum II.

Anogenital region ( Figs 7B, C ). Genital (g 1: 19–22; g 2 – g 4: 11–13), aggenital (22), anal (22), and adanal (22) setae setiform, thin, roughened. Adanal lyrifissure distinct, close and parallel to anal plate. Marginal porose area band-like.

Legs ( Figs 8D–G ). Median claw thick; lateral claws thin, with small tubercle distoventrally; all claws slightly barbed on dorsal side. Ventrobasal tubercle of tibiae I, II well observable. Femur II broadly rounded ventrodistally. Proximoventral porose area on tarsi I–IV and distoventral porose area on tibiae I–IV present but poorly visible; dorsoparaxial porose area on femora I–IV and on trochanters III, IV distinct. 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 . Seta s on tarsus I eupathidial, located between (u) and (a).

Remarks. The new species is similar to S. (T.) scheloribatoides ( Ramsay, 1966) (= Setobates minor Hammer, 1967 ) from New Zealand in the presence of lanceolate bothridial seta, 13 pairs of minute notogastral setae and tridactylous legs, but differs from the latter by the absence (versus presence) of the prolamella, distinctly longer aggenital, anal and adanal setae, and narrower body.

Etymology. The specific epithet tredecim refers to the presence of 13 pairs of setae on the notogaster.

Figures

FIGURE 7. Scheloribates (Topobates) tredecim Ermilov sp. nov., adult: A—dorsal view (legs omitted); B—ventral view (legs omitted); C—right lateral view (legs omitted). Scale bar 100 μm.

FIGURE 8. Scheloribates (Topobates) tredecim Ermilov sp. nov., adult: A—subcapitulum, ventral view; B—palp, right, antiaxial view; C—chelicera, left, paraxial view; D—leg I, right, antiaxial view; E—leg II, left, paraxial view; F—leg III, left, antiaxial view; G—leg IV, left, antiaxial view. Scale bars 20 μm (A, C), 10 μm (B), 50 μm (D–G).