Scheloribates (Scheloribates) monosetosus Ermilov, 2024

Ermilov, Sergey G., Rybalov, Leonid B. & Kuzmicheva, Evgeniya A., 2024, New Scheloribates (Acari, Oribatida, Scheloribatidae) from Ethiopia, Zootaxa 5492 (2), pp. 176-190 : 181-183

Scheloribates (Scheloribates) monosetosus Ermilov sp. nov.

( Figs 3 , 4 )

Material. Holotype (female) and five paratypes (two males and three females): Southeastern Ethiopia, Oromia Region, Bale Zone, Bale Mountains National Park , 6°48′40.7″N, 39°51′07.7″E, 4050 m a.s.l., Sanetti Plateau , Afroalpine community, predominance of cushion-shaped shrubs of Helichrysum citrispinum and H. splendidum , co-dominance of Festuca richardii , Pentaschistis pictigluma , Agrostis quinqueseta , and Alchemilla haumannii , litter, 16.XI.2014 (E. Kuzmicheva).

The holotype is deposited in the collection of the Senckenberg Museum of Natural History, Görlitz, Germany; five 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 large, length: 885–960. Notogaster broad. Rostrum protruding, rounded. Prolamella complete; translamella represented by two short lines near lamellae. Rostral, lamellar and interlamellar setae long, setiform, barbed; in ˃ le ˃ ro; bothridial seta long, lanceolate, barbed. One pair of notogastral setae (p 1) short, needleform; other setae represented by alveoli. Circumpedal carina long. Anal and adanal setae medium-sized, setiform, thin, roughened. Ventrobasal tubercle of leg tibiae I, II absent; femur II broadly rounded ventrodistally; tarsus I with 19 setae (l” absent; v’ present); genu II with two setae (v’ absent).

Description of adult. Measurements. Body length: 885 (holotype), 885–960 (paratypes); body width (level of pteromorph): 780 (holotype), 705–810 (paratypes); width of ventral plate: 690 (holotype), 615–690 (paratypes). No differences between males and females in body size.

Integument. Body color brown to dark 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 3A, C ). Rostrum protruding, rounded. Lamella about 1/2 length of prodorsum; prolamella complete (reaching insertion of ro); translamella represented by two short lines near lamellae; sublamella and lateral keel-shaped ridge distinct; sublamellar porose area (13–15) rounded. Rostral (131–142), lamellar (210–214) and interlamellar (281–307) setae setiform, barbed; bothridial seta (120–124) with lanceolate, barbed head, directed posterolaterad; bothridial stalk slightly longer than head; exobothridial seta (22–30) setiform, thin, roughened. Dorsosejugal porose area oval, poorly visible.

Notogaster ( Figs 3A, C ). Anterior notogastral margin convex medially. Notogaster broad. Pteromorph large, broadly rounded laterally, its anterior margin straight (perpendicular to longitudinal axis of body in dorsal aspect) or slightly convex. Nine pairs of notogastral setae represented by alveoli and one pair (p 1) by needleform (34–37) setae. Four pairs of saccules with small opening and drop-like channel. Opisthonotal gland opening and all lyrifissures (except ia) distinct.

Gnathosoma ( Fig. 3B ). Generally, similar to S. (S.) flexibilis . Subcapitulum size: 169–184 × 131–139; subcapitular setae (a: 34–41; m: 28–34; h: 64–75) setiform, roughened; m thinner than a and h; both adoral setae (19) setiform, barbed. Palp length: 112–116; postpalpal seta (9) spiniform, roughened. Chelicera length: 184–191; setae (cha: 60–64; chb: 41–45) setiform, barbed.

Epimeral and lateral podosomal regions ( Figs 3B, C ). Epimeral formula: 3–1–3–3; all setae (1a, 2a, 3a: 26–34; 1b, 3b, 3c: 60–75; others: 34–49) setiform, thin, roughened. Humeral porose areas Am and Ah not observable. Pedotectum II rounded laterally in ventral aspect. Discidium triangular, with rounded top. Circumpedal carina long, directed to pedotectum II.

Anogenital region ( Figs 3B, C ). Genital (g 1: 34–49; g 2 – g 4: 22–34), aggenital (22–34), anal (41–56), and adanal (56–64) setae setiform, thin, roughened; both aggenital setae absent in the holotype. Adanal lyrifissure distinct, close and parallel to anal plate. Marginal porose area band-like, sometimes shortly interrupted.

Legs ( Figs 4A–D ). Median claw thick; lateral claws thin, with small tubercle distoventrally; all claws slightly barbed on dorsal side. Ventrobasal tubercle of tibiae I, II absent. Femur II broadly rounded ventrodistally. Proximoventral porose area on tarsi I–IV, distoventral porose area on tibiae I–IV, 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 setiform (not eupathidial), barbed, located between (a) and (pv).

Remarks. The new species is similar to S. (S.) concentricus Balogh, 1962 from Tanzania in the presence of large body size, one pair of remaining notogastral setae (p 1), protruding rostrum, and bothridial seta with elongate head, but differs from the latter by the presence of medium-sized (versus short) anal and adanal setae, short (versus medium-sized) translamellar lines near lamellae and lanceolate (versus fusiform) bothridial seta.

Etymology. The specific epithet monosetosus refers to the presence of one pair of notogastral setae.

Figures

FIGURE 3. Scheloribates (Scheloribates) monosetosus Ermilov sp. nov., adult: A—dorsal view (legs omitted); B—ventral view (legs and part of right pteromorph omitted); C—right lateral view (gnathosoma and legs omitted). Scale bar 200 μm.

FIGURE 4. Scheloribates (Scheloribates) monosetosus Ermilov sp. nov., adult:A—leg I, right, antiaxial view; B—leg II, right, antiaxial view; C—leg III, left, antiaxial view; D—leg IV, left, antiaxial view. Scale bar 100 μm.