Ramusella (Insculptoppia) quintanaensis, Ermilov & Kontschán, 2023

Ermilov, Sergey G. & Kontschán, Jenő, 2023, Three new species of Oppiidae (Acari, Oribatida) from Mexico, Zootaxa 5360 (1), pp. 113-126 : 121-124

Ramusella (Insculptoppia) quintanaensis sp. nov.

( Figures 5 , 6 )

Type material. Holotype (female) and seven paratypes (seven females): Mexico, 20°41’N, 87°03’W, Quintana Roo, Municipio de Solidaridad, vicinities of Playa del Carmen, leaf litter in a large karst pit under trees and bushes in secondary semi-evergreen tropical forest (data and collector unknown; collection of the Tyumen State University Museum of Zoology, Tyumen, Russia; Gashev et al. 2005).

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 70% solution of ethanol with a drop of glycerol.

Diagnosis. Body length: 165–180. Rostrum rounded. Costulae and transcostula forming elongate trapezoid structure. Rostral, lamellar and interlamellar setae setiform, slightly barbed (ro longest); bothridial seta pectinate (head absent), with 11–12 branches. Interbothridial region with three pairs of muscle sigillae and one pair of interbothridial tubercles. Notogastral seta c represented by alveolus or completely absent; other setae short, setiform, slightly roughened; la inserted slightly posterolateral to lm. Epimeral and anogenital setae short, setiform, slightly roughened. Discidium pointed distally.

Description. Measurements. Body length: 180 (holotype), 165–180 (paratypes); body width: 90 (holotype), 90–97 (paratype).

Integument ( Fig. 5C ). Body color light brown. Body surface mostly smooth but lateral part of body between bothridium and acetabula I–III densely microtuberculate (diameter of tubercle up to 2).

Prodorsum ( Figs 5A, C ). Rostrum rounded. Costulae and transcostula present, thin, forming elongate trapezoid structure; sometimes angles of these structure point. Rostral (17–19), lamellar (9–11), interlamellar (13–15), and exobothridial (9–11) setae setiform, slightly barbed; le and ex thinner than ro and in; le inserted behind transcostula or on it; bothridial seta (45–49) pectinate (head absent), with 11–12 branches on one side and several barbs on opposite side. Interbothridial region with three pairs of muscle sigillae and one pair of short slight longitudinal carinae connected with simple interbothridial tubercle; postbothridial tubercle present but poorly observable; slight triangular tubercle developed posterolateral to bothridium. Lateral carina present, short, arch-like.

Notogaster ( Figs 5A, C ). Anterior border convex medially. Notogastral seta c represented by alveolus or completely absent; other setae short (9–11) setiform, slightly roughened; la inserted slightly posterolateral to lm. All notogastral lyrifissures and opisthonotal gland opening distinct.

Gnathosoma ( Figs 6A–C ). Subcapitulum size: 41–45 × 34–37; subcapitular setae (a: 7–11; m, h: 11–15) setiform, a and h slightly roughened, m sparsely barbed unilaterally; both adoral setae (4–5) setiform, smooth. Palp length: 34–37; formula: 0–2–1–3–9(+ω); solenidion medium-sized, bacilliform, appressed to tarsus surface and located in its mediodistal part; postpalpal seta (2) spiniform, smooth. Chelicera length: 41–45; seta cha (11–13) setiform, with strong barbs unilaterally, chb (7–9) setiform, barbed; antiaxial side of chelicera with two diagonal ridges.

Epimeral and lateral podosomal regions ( Figs 5B, C ). Epimeral setal formula: 3–1–3–3; all setae (5–7) setiform, slightly roughened. Ventrosejugal tubercles absent but several slight tubercle-like thickenings observable. Epimeral border IV arch-like. Discidium present, pointed distally.

Anogenital region ( Figs 5B, C ). Genital (5–7), aggenital (7–9), adanal (7–9), and anal (5–7) setae setiform, slightly roughened. Adanal lyrifissure located close and parallel to anal aperture.

Legs ( Figs 6D–G ). Claw of each leg smooth. Trochanter III with posterior tooth. Porose area on femora I–IV and on trochanters III, IV not observable. Formulas of leg setation and solenidia: I (1–5–2–4–20) [1–2–2], II (1–5– 2–4–16) [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 . Setae p’ and p” setiform on tarsus I versus very short, conical on tarsi II–IV; seta s eupathidial on tarsus I; famulus short, erect, slightly swollen distally, located medial to solenidion ω 1. Solenidia ω 1 on tarsus I, ω 1 and ω 2 on tarsus II, φ 2 on tibia I, σ on genu III medium-sized, thickened, rounded distally; φ 1 on tibia I and φ on tibia IV very long, subflagellate; other solenidia medium-sized, rod-like or slightly thickened.

Remarks. Ramusella (Insculptoppia) quintanaensis sp. nov. is morphologically similar to R. (I.) soror ( Balogh, 1958) from the Afrotropical region and Caucasus (see Balogh 1958, 1961) in the absence of developed head on the bothridial seta, but differs from the latter by the smaller body length (165–180 versus 300), the morphology of the rostrum (not protruding, broadly rounded versus protruding, narrowly rounded), the presence (versus absence) of transcostula and one pair of interbothridial tubercles, and the position of notogastral setae la (slightly posterolateral to lm versus slightly anterolateral to lm).

From the Neotropical Ramusella -species, R. (I.) quintanaensis sp. nov. is morphologically similar to R. (R.) hippy ( Mahunka, 1983) from Mexico (see Mahunka 1983) in having elongate trapezoid costular-trancostular complex and the absence of developed head on the bothridial seta, but differs from the latter by the smaller body length (165–180 versus 204–213), the morphology of the rostrum (rounded versus incised medially), the presence of one pair of interbothridial tubercles (versus tubercles absent but three longitudinal ridges developed), and short (versus medium-sized) notogastral setae.

Etymology. The species name quintanaensis refers to the place of origin, the Free and Sovereign State of Quintana Roo.

Figures

FIGURE 5. Ramusella (Insculptoppia) quintanaensis sp. nov., adult (gnathosoma and legs omitted): A—dorsal view; B— ventral view; C—right lateral view. Scale bar 50 μm.

FIGURE 6. Ramusella (Insculptoppia) quintanaensis 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 (tarsus omitted), left, paraxial view; F—leg III (tarsus omitted), right, ventroparaxial view; G—leg IV, left, antiaxial view. Scale bars 20 μm (D–G), 10 μm (A–C).