Pergalumna paraobsidiana, Ermilov, 2024

Ermilov, Sergey G., 2024, Additions to the oribatid mite (Acari, Oribatida) fauna of Guatemala, with description of a new species of Pergalumna, Persian Journal of Acarology 13 (3), pp. 361-373 : 367-371

Pergalumna paraobsidiana sp. nov. ( Figs. 1–12 )

http://zoobank.org/ urn:lsid:zoobank.org:act:2128D02D-CAA8-4DEF-8CF8-7AECB8779CF7

Type material

Holotype (male) and five paratypes (two males and three females): Eastern Guatemala, Izabal Department, Las Escobar , 8 km SW Puerto Barrios, rainforest litter, 12–14.XI.1986 (E.E. Lindquist).

Type deposition

The holotype is deposited in the collection of the Canadian National Collection, Ottawa, Canada; five 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: 525–570. Prodorsum, pteromorph, ventral plate, and posterior part of notogaster densely tuberculate; anterior and central parts of notogaster with dense short longitudinal ridges. Rostrum pointed. Rostral, lamellar and interlamellar setae long, setiform, barbed; relative length: in˃le˃ro; bothridial seta long, setiform, unilaterally shortly ciliate. Dorsosejugal porose area present. Dorsosejugal suture present but indistinct. Three pairs of porose areas present: Aa and A3 oval; A1 elongate oval; Aa located between la and lm, closer and anteromedially to la. Median pore absent. Circumpedal carina directed to insertion of seta 3b. Epimeral and anogenital setae comparatively short. Postanal porose area absent. Leg famulus curved mediodistally, directed forwards, inserted between solenidia ω 1 and ω 2; solenidion on tibia IV with well-developed swollen mediobasal part, inserted in posterior part of the segment.

Description

Measurements – Body length: 540 (holotype), 525–570 (paratypes); notogaster width: 405 (holotype), 375–420 (paratypes). No differences between males and females in body size.

Integument – Body color brown. Body surface densely microgranulate sculpturing; additionally, prodorsum, pteromorph, ventral plate (including subcapitular mentum and genital and anal plates), and posterior part of notogaster densely tuberculate; anterior and central parts of notogaster with dense short longitudinal ridges.

Prodorsum – Rostrum pointed. Lamellar and sublamellar lines thin, parallel, curving backwards mediodistally. Rostral (67–75), lamellar (97–105) and interlamellar (124–127) setae setiform, barbed; le removed from L; bothridial seta (153–161) setiform, unilaterally shortly ciliate. Dorsosejugal porose area elongate oval (15–19 × 5), located posterolaterally to insertion of in. Dorsophragma comparatively long.

Notogaster – Dorsosejugal suture present but indistinct. All notogastral setae represented by setal alveoli. Three pairs of porose areas developed; Aa (30–37 × 15–19) and A3 (22–30 × 15–19) oval; A1 (45–60 × 15–19) elongate oval; Aa located between la and lm, closer and anteromedially to la. Median pore absent. Opisthonotal gland opening and all lyrifissures distinct: gla located laterally to A1; im anterolaterally to A1; ip between p 1 and p 2, closer to p 2; ih and ips close to each other, anteriorly to p 3.

Gnathosoma – Size of subcapitulum: 139–142 × 120–124; subcapitular (a, h: 28–30; m: 30–34) and adoral (15–17) setae setiform, barbed. Length of palp: 105–112; setation: 0–2–1–3–9(+ω); postpalpal seta (5) spiniform, smooth. Length of chelicera: 187–191; setae (cha: 52–56; chb: 37–39) setiform, barbed.

Epimeral and lateral podosomal regions – Epimeral setal formula: 1–0–2–3; setae (4a, 4b: 11; 1b: 17–19; 3b: 22–26; 3c, 4c: 30–34) setiform, smooth. Circumpedal carina medium-sized, directed to insertion of seta 3b.

Anogenital region – Anogenital formula: 6–1–2–3; genital (g 1: 17–19; others: 11), aggenital (11), anal (11), and adanal (11) setae setiform, roughened; anterior edge of genital plate with two setae; aggenital seta located between genital and anal apertures, slightly closer to the former; adanal setae ad 1 and ad 2 posteriorly, ad 3 laterally to anal plate; distance ad 1 – ad 2 shorter than ad 2 – ad 3. Adanal lyrifissure located close and parallel to anal plate. Postanal porose area absent.

Legs – Median claw distinctly thicker than lateral claws; all claws slightly barbed on dorsal side. Porose area on femora I–IV and on trochanters III, IV poorly visible; proximoventral porose area on tarsi and distoventral porose area on tibiae not observable. Formulas of leg setation and solenidia: I (1–4–3–4–20) [1–2–2], II (1–4–3–4–15) [1–1–2], III (1–2–1–3–15) [1–1–0], IV (1–2–2–3–12) [0–1– 0]; homology of setae and solenidia indicated in Table 1; famulus curved mediodistally, directed forwards, inserted between solenidia ω 1 and ω 2; solenidion on tibia IV with well-developed swollen mediobasal part, inserted in posterior part of the segment.

Comparison

Pergalumna obsidiana sp. nov. is most similar to P. obsidiana Palacios-Vargas & Villagómez, 2017 and P. ekaterinae Páez, Villagómez & Palacios-Vargas, 2019 from Mexico in the following main traits: rostrum pointed; bothridial seta long, setiform, shortly ciliate; rostral, lamellar and interlamellar setae long; solenidion of the leg tibia IV with mediobasal swollen part.

The new species differs from P. obsidiana by the following traits: body size larger (length: 525– 570 versus 443–513); anterior and central parts of notogaster with dense short longitudinal ridges (versus tuberculate); genital plate tuberculate (versus with strong transverse ridges); and rostral region without longitudinal ridge (versus with ridge).

The new species differs from P. ekaterinae by the following traits: body size larger (length: 525– 570 versus 434–503); prodorsum, pteromorph, ventral plate, and posterior part of notogaster densely tuberculate, and anterior and central parts of notogaster with dense short longitudinal ridges (versus surface without heavy sculpturing); notogaster with three pairs (versus four pairs) of notogastral porose areas; posterior part of notogaster without striate bands (versus with bands).

Etymology

The species name paraobsidiana refers to the similarity between the new species and P. obsidiana .

Figures

Figures 1–4. Pergalumna paraobsidiana sp. nov. (adult) – 1. Dorsal view of body; 2. Ventral view of body (legs and right pteromorph not shown); 3. Right lateral view of body (gnathosoma, legs and right pteromorph not shown); 4. Posterior view of body (part of left half not shown).

Figures 5–12. Pergalumna paraobsidiana sp. nov. (adult) – 5. Anterior view of prodorsum, dorsoanterior view; 6. Subcapitulum, ventral view; 7. Palp, left, paraxial view; 8. Chelicera, left, paraxial view; 9. Leg I, right, antiaxial view; 10. Leg II (trochanter not shown), right, antiaxial view; 11. Leg III, left, antiaxial view; 12. Leg IV, left, antiaxial view.