Neoamerioppia (Neoamerioppia) mexicoensis, Ermilov & Kontschán, 2023

Ermilov, Sergey G. & Kontschán, Jenő, 2023, Three new species of Oppiidae (Acari, Oribatida) from Mexico, Zootaxa 5360 (1), pp. 113-126 : 118-121

Neoamerioppia (Neoamerioppia) mexicoensis sp. nov.

( Figures 3 , 4 )

Type material. Holotype (female) and seven paratypes (five males and two 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: 285–330. Rostrum protruding, triangularly narrowed. Costula and transcostula absent. Rostral and lamellar setae setiform, barbed (ro longer and thicker than le); bothridial seta clavate, barbed (head and stalk similar in length). Interbothridial region with three pairs of muscle sigillae. Notogastral seta c very short, setiform, smooth; other setae short (la, lm, lp, h 1 – h 3 long; p 1 – p 3 medium-sized) setiform, with flagellate tip, barbed. Epimeral setae short or medium-sized, setiform, slightly barbed. Discidium present, pointed distally. Genital setae short; other anogenital setae medium-sized, slightly barbed. Leg tarsus II with one solenidion.

Description. Measurements. Body length: 315 (holotype), 285 (male paratypes), 315–330 (female paratypes); body width: 195 (holotype), 165 (male paratypes), 195–203 (female paratypes).

Integument ( Fig. 3C ). 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 3A, C ). Rostrum protruding, triangularly narrowed. Costula and transcostula absent. Rostral (37–41), lamellar (26–30) and exobothridial (15–17) setiform, barbed; ro thickest, ex thinnest; bothridial seta (37– 41) clavate, barbed; head and stalk similar in length. Interbothridial region with three pairs of muscle sigillae; postbothridial tubercle present; triangular tubercle located posterolateral to bothridium. Small oval porose area located posterior to bothridium. Lateral carina absent.

Notogaster ( Figs 3A, C ). Anterior border convex medially. Notogastral seta c (7) setiform, smooth; other setae (la, lm, lp, h 1 – h 3: 67–71; p 1 – p 3: 37–41) setiform, with flagellate tip, barbed; la inserted posterolateral to lm. All notogastral lyrifissures (except ip not observable) and opisthonotal gland opening distinct.

Gnathosoma ( Figs 4A–C ). Subcapitulum size: 67–71 × 52–56; subcapitular setae (a: 13–15; m: 18–20; h: 20–22) setiform, a and h slightly barbed, m sparsely barbed unilaterally; both adoral setae (5) setiform, smooth. Palp length: 43–45; formula: 0–2–1–3–8(+ω); solenidion short, swollen distally, appressed to tarsus surface and located in its mediodistal part connected with setae ul; postpalpal seta (4) spiniform, smooth. Chelicera length: 67–71; seta cha (19) setiform, with strong barbs unilaterally, chb (13) setiform, barbed; antiaxial side of chelicera with three diagonal ridges.

Epimeral and lateral podosomal regions ( Figs 3B, C ). Epimeral setal formula: 3–1–3–3; all setae (3c: 32–34; 1a, 1c, 2a, 3a: 9–11; 1b, 3b, 4a, 4b, 4c: 26–28) setiform, slightly barbed. Epimeral border IV arch-like. Discidium present, pointed distally.

Anogenital region ( Figs 3B, C ). Genital (7), aggenital (19–22), adanal (19–22), and anal (15–17) setae setiform, genital setae roughened, others slightly barbed. Adanal lyrifissure located close and parallel to anal aperture.

Legs ( Figs 4D–G ). Claw of each leg smooth. Trochanter III with posterior tooth. Porose area on femora I–IV and on trochanters III, IV present, large, covering antiaxial and paraxial sides. Formulas of leg setation and solenidia: I (1–5–2–4–20) [1–2–2], II (1–5–2–4–16) [1–1–1], 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 . Light tubercle located between famulus and solenidion ω 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 posterior to solenidion ω 1. Solenidia ω 1 on tarsus I, ω on tarsus II and σ on genu III medium-sized, thickened, rounded distally; φ 1 on tibia I very long, subflagellate; other solenidia medium-sized or long, rod-like or setiform.

Remarks. Neoamerioppia (Neoamerioppia) mexicoensis sp. nov. is morphologically similar to N. (N.) aelleni ( Mahunka, 1982) from Fiji (see Mahunka 1982) and N. (N.) flagelliapex Ohkubo & Aoki, 1995 from Mariana Islands (see Ohkubo & Aoki 1995) in having long notogastral setae with flagellate tip, but differs from both by the morphology of the rostrum (protruding, triangularly narrowed versus not protruding, rounded), medium-sized bothridial seta, with similar length of head and stalk (versus bothridial seta long, head distinctly shorter than stalk), and the absence (versus presence) of prodorsal costulae. Also, N. (N.) aelleni has short (versus long in the new species) notogastral seta h 1; N. (N.) flagelliapex is larger (body length: 414–438 versus 285–330 in the new species) and has rostral setae located comparatively very close to each other (versus distant from each other in the new species).

Etymology. The species name mexicoensis refers to the country of origin, Mexico.

Figures

FIGURE 3. Neoamerioppia (Neoamerioppia) mexicoensis sp. nov., adult (gnathosoma and legs omitted): A—dorsal view; B—ventral view; C—right lateral view. Scale bar 100 μm.

FIGURE 4. Neoamerioppia (Neoamerioppia) mexicoensis 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), right, ventroantiaxial view; F—leg III (tarsus omitted), left, ventroantiaxial view; G—leg IV, right, paraxial view. Scale bars 50 μm (D–G), 20 μm (A–C).