Dissomphalus oksanae, Fadeev, 2022

Fadeev, Kirill I., 2022, First record of Dissomphalus Ashmead (Hymenoptera: Bethylidae) from Russia with description of a new species, Zootaxa 5099 (3), pp. 382-390 : 385-389

Dissomphalus oksanae sp. nov.

( Figs 1–3 )

Description. Holotype. Male. Measurements. Body length ca. 3.0 mm; forewing length 2.2 mm, maximum forewing width 0.86 mm, hind wing length 1.7 mm, hind wing width 0.42 mm; HL 0.5 mm; HW 0.5 mm; WF 0.33 mm; OOL 0.2 mm; EL 0.2 mm; AOL 0.066 mm; WOT 0.15 mm; DAO 0.033 mm; POL 0.066 mm; LM 0.916 mm; LP 0.2 mm; WP 0.45 mm; LMPD 0.33 mm; WMPD 0.33 mm. Width of hypopygium 0.33 mm.

Colour. Head and mesosoma dark brown. Tegula, pronotal collar, mandible, and antenna brown. Palpi beige. Metasoma from brown ventral part of petiole, to brown-orange. Legs from brown at base to pale yellow-brown. Wings hyaline, veins pale. Genitalia yellow, distal part of harpe light brown.

Head. ( Fig. 1 B–G ) Head as long as wide. Mandible with three apical teeth; ventral tooth acute and largest ( Fig. 1 G ). Median clypeal lobe weakly protruded anterad and ventrad and wedge-shaped with sides incurved and slightly undulating; apex rounded. Median clypeal carina low, incurved in lateral view. Lateral clypeal lobe moderately developed, rounded. Eye with short erect setae. Ocelli equal-sized and arranged in almost equilateral triangle, frontal angle of ocellar triangle acute. Occipital carina completed, thin, cellular at base, in height to 0.3 DAO. Head surface with reticulate pattern and slender sparse punctures spaced at least one seta’s length apart. First five antennomeres in ratio of 13:5:5:5: 5 in length. Flagellomeres with sparse oval-pitted sensillae and erect setae. WF 0.66 × HW, WF 1.65 × EL, OOL 1.33 × WOT, POL = AOL, DAO 0.22 × WOT.

Mesosoma . ( Fig. 2 A–C ) Pronotum and mesonotum matte, with fine punctures and reticulate pattern dorsally and laterally. Dorsal pronotal area trapezoidal, with incurved posterior border. Transverse pronotal carina weakly expressed. LP 0.44 × WP. Anteromesoscutum elliptical, convex. Notauli distinct, narrow, not almost reaching posterior margin of mesoscutum, converging posteriorly. Parapsidal signum narrowly presented posteriorly. Posterior margin of mesoscutum with slender sulcus. Mesoscutellar disc triangular, with pair mesoscuto-scutellar pits anteriorly, forming together trapezoid depression extending posteriorly with posterior margin slightly incurved. Gap between these pits weakly expressed. Metanotal trough with longitudinal ridges. Mesopleuron reticulate, mesopleural pit and mesepimeral sulcus present. Metapectal-propodeal disc as long as wide, its posterior part rounded, posterior margin outcurved; metapostnotal median carina not reaching posterior margin of disc, present on 0.85 of anterior disc length, low and slightly sinuous, with short transverse wrinkles; lateral carina of metapectal-propodeal complex low; pair of transverse posterior carinae developed in anterior third of disc; basal triangular area of disc weakly reticulate-wrinkled; posterior third and lateral area of disc polish and shiny.

Wings. ( Fig. 2 D ) Forewing with costal (C) and subcostal (Sc+R) veins closely placed and parallel, but rolledup anterior wing edge in photo. Pterostigma slender. Poststigmal abscissa of R1 vein thin, equal to half of 2r-rs&Rs vein. R1 vein as long as pterostigma. 2r-rs&Rs vein long and smooth.

Metasoma. ( Fig. 1 H , 2 E ) Рetiolate, smooth and shining. Metasomal tergum II with pair smooth oval depressions in its mediolateral part; depressions relatively large, distant each other about their maximum diameter, with one–three setae anterolaterally; small low tubercles in its median part without tuft of setae. Hypopygium ( Fig. 3 G ) subtrapezoid, minimum width 0.56 × its maximum width, with anterior and posterior margins weakly incurved; anterior margin with long median spiculum as long as hypopygium and two pairs of anteromedial apodeme along sides; posterior margin with low median callus and two small lateral depressions. Median part of hypopygial plate in sparse long setae, their length up to half length of hypopygium.

Genitalia. ( Fig. 3 A–F, H ) Very broad, mittens-like. Genital ring thin. Aedeagal dorsal valva at basal quarter with flat plate, emblem-shaped; median quarters with median ridge on dorsal surface turning into median rounded tooth; apical quarter with pair of apical lobes, membranous and leaf-like and rounded with row of fine setae on outer margin ( Fig. 3 C ). Aedeagal ventral valve bifurcated; its parts wedge-shaped, elongated and narrowed distally, apex sharpened, as long as dorsal valve. Apical end of harpe sclerotized, hook-shaped, curved mesad, apex rounded with 5–6 apical setae. Volsella G-like shape ( Fig. 3 F, H ), with seta on inner margin; basivolsella without tooth. Cuspis arched. Digitus with basal projection in form of curved back tooth. Apodeme reaching genital ring.

Female. Unknown.

Type material. Holotype: ♂, RUSSIA, Krasnodar Territory, Krasnodar, VNIIBZR [= All-Russian Research Institute of Biological Plant Protection , Entomological Reservation ], 45°02’56.1”N 38°52’32.4”E, 13.VII.2013, Malaise trap, O. Kosheleva leg. ( ZISP) . Paratypes: 8 ♂, with same labels as in holotype (6 ♂ in ZISP, 2 ♂ in ZMMU).

Biology. Unknown.

Variation: Forewing length 2.0– 2.2 mm, maximum forewing width 0.78–0.86 mm; HL 0.50–0.53 mm; HW 0.48–0.50 mm; WF 0.30–0.33 mm: LM 0.91–0.96 mm; WP 0.42–0.45 mm; LMPD 0.30–0.35 mm; WMPD 0.27– 0.33 mm.

Distribution: Russia, Krasnodar Territory.

Etymology. This species is named in honor to Oksana V. Kosheleva (St Petersburg, Russia), a Russian chalcidologist and expert for the family Eulophidae , who collected the type series of this species.

Remarks. A new species is similar in external morphology to male of D. kyushuensis by having an elongated and single-toothed median lobe of clypeus, but differs of them by the following characters: 1) presence the sharp angle and a rounded apex of median lobe of clypeus (vs median lobe dully angulate medially), 2) head, pronotum, and mesonotum finely punctured (vs impunctate), 3) ocelli in an equilateral triangle (vs in obtuse ocellar triangle), 4) mesoscuto-scutellar pits forming together trapezoid depression extending posteriorly with posterior margin slightly incurved, medial partition weakly expressed (vs elongated rectangular depression non-separable into two pits), 5) metapectal-propodeal disc with the same width and length and its slightly outcurved sides, as well as rounded posterior side and posterior margin outcurved (vs 0.77 × as long as wide and parallel sides and posterior margin straight), 6) metapostnotal median carina metapectal-propodeal disc not reaching posterior margin of disc, present on 0.85 of disc length (vs reaching posterior margin of disc), 7) metasomal tergum II with pair large and smooth depressions, with a pit on median part (vs oval depressions laterally, depressions with a pit on its anterior portion).

I do have not the morphological basis for comparing a male of a new species with the females of three known European species due to their great sexual dimorphism.

Figures

FIGURE 1. Dissomphalus oksanae sp. nov. (♂; A–E, H—holotype; F, G—paratype). A. Habitus, lateral view. B. Clypeus, frontal view. C. Head, lateral view. D. Head, dorsal view. E.Antenna. F. Head, ventral view. G. Mandibles. H. Metasomal tergum I–II, dorsal view. Scale bars: 0.5 mm for A, E; 0.25 mm for B–C, F, H; 0.1 mm for G.

FIGURE 2. Dissomphalus oksanae sp. nov. (♂; A, B, D, E—holotype; C– paratype). A. Mesosoma, dorsal view. B. Meso- soma, lateral view. C. Mesosoma, ventral view. D. Forewing. E. Metasoma, dorsal view. Scale bars: 0.25 mm for A–C, E; 0.5 mm for D.

FIGURE 3. Dissomphalus oksanae sp. nov. (♂; A, B, D, E, G—holotype; C, F, H—paratype).A. Genitalia, ventral view, from slide. B. Genitalia, dorsal view, from slide. C. Apical lobe of aedeagus, lateral view. D. Genitalia, ventral view. E. Genitalia, dorsal view. F. Volsella, dorsal view. G. Hypopygium, outer view. H. Volsella, ventral view. Scale bars: 0.25 mm for A, B, G; 0.1 mm for H.