Arkadiserphus leleji Rasnitsyn, 2021

Rasnitsyn, Alexandr P., 2021, First Jurassic representative of the extinct family Peleserphidae (Hymenoptera, Proctotrupoidea), Journal of Hymenoptera Research 84, pp. 295-300 : 295

Arkadiserphus leleji Rasnitsyn sp. nov.

Figure 1

Holotype.

PIN, 2784/1225; near Mikhailovka village, southern Karatau Range, S. Kazakhstan; Karabastau Formation, Upper Jurassic; lateral imprint of whole insect with incomplete legs and obliterate details of body structure.

Diagnosis.

Same as for the genus because of monotypy.

Description.

Female (male unknown). As preserved, body and appendages dark except that fore and mid tibiae, tarsi and hind tarsi distally paler.

Head: Rather small (in side view), eyes large, almost perfectly circular, distant from mandible base for less than basal width of mandible, temples very narrow, clypeus rather long, with details obscure. Antenna 13-segmented, long (probably reaching half-length of metasoma), with scape thick, ca. 1.5 × as long as wide, pedicel small, subquadrate in side view, flagellomeres 1-6 similar in length and width, about as long as scape and pedicel combined and slightly narrower than pedicel, following flagellomeres distinctly shorter and wider, with apical segment longest. Mandibles of medium size, apparently narrowed apically and with two apical teeth.

Mesosoma: Details rather obscure, pronotum convex and moderately narrow dorsally, mesonotum weakly convex, occupying more than half of mesosoma dorsum, metanotum moderately short, convex, propodeum also moderately short, convex. Coxae medium-sized, hind ones moderately enlarged, fore and middle trochanters rather thin, elongate, hind one wider, possibly subquadrate, trochantelli not visible except possibly hind one, if correctly interpreted, of size similar to that of hind trochanter. Femora short and moderately thick (about 3.0-3.3 × as long as wide), most tibiae thin and short, but hind one very long (ca. 1.7 × as long as femur). Forewing ca. 2.5 × as long as wide, with pterostigma dark, 3.3 × as long as wide, with 2r-rs near its base, RS base distant from pterostigma at length of 1-RS, 2r-rs almost as long as 1-RS, 2-RS+M as long as 1-RS, 3-RS+M very short and of different length in right and left wings, cell 3r (marginal) ca. 0.8 × as long as its distance to wing apex, Cu with very slight kinks at 1cu-a and 2cu-a, 1-Cu ca. 0.5 × as long as 2cu-a, 2cu-a complete, meeting A at right angle. Hind wing with only R visible.

Metasoma: Somewhat distended because of postmortem decomposition, preserved subovate, slightly longer than head and mesosoma combined, widely connected with propodeum, with all visible terga and sterna free (apical terga apparently hidden under 7th one), neither strongly shortened nor elongate but some of them (terga I, V, VII and sterna 1, 2, 6) 0.5-0.7 × as long as others. Ovipositor sheaths thin, slightly bent downward, their visible parts as long as pterostigma and marginal cell combined.

Measurements

(mm). Length of body 4.8, head 0.63, antenna 3.62, mesosoma 1.89, fore femur 0.69, fore tibia 0.44, mid tibia 0.71, hind tibia 1.36, fore wing 2,64, metasoma 2.56, ovipositor sheath 0.82.

Material.

Holotype only.

Etymology.

Species name is also dedicated to Prof. Arkady Lelej.

Figures

Figure 1. Arkadiserphus leleji sp. nov., holotype A general appearance, side view B interpretation (cly, clypeus; cx 1, cx 2, cx 3, pro-, meso- and metacoxa; f 1, f 2, pro- and mesofemur; md, mandible; N 1, N 2, N 3, pro-, meso- and metanotum; ppd, propodeum; scl 2, mesoscutellum; ti 3, hind tibia; tl 3, hind trochantellus; I-VII, metasomal terga; 1 - 6, metasomal sterna) C fore wing (vein names standard). Scale bar: 1 mm.