Adelius myriolus, Belokobylskij & Lee & Ku, 2024

Belokobylskij, Sergey A., Lee, Hye-Rin & Ku, Deokseo, 2024, The genus Adelius Haliday, 1833 in the fauna of Korean Peninsula (Hymenoptera: Braconidae: Cheloninae: Adeliini), Zootaxa 5468 (1), pp. 167-178 : 172-177

Adelius myriolus sp. nov.

http://zoobank.org/ 197DB9FC-5287-46C2-9AB3-8CF9EB565887

Figs 3 , 4

Type material. Holotype: female, “ Korea ( JJ) Dongbok-ri, Gujoa-up, Jeju-si , Jeju-do, IX.10 ~ IX.24.2017 (Malaise Trap)” ( NIBR).

Paratypes. 1 female, “ Korea (GB) Uiseong-gun, Angye-myeon, Dodeok-ri , 16.VIII ~ 29.VIII.2017, Hyung-Geun Lee , Malaise trap, N 36°25’49.02”, E 128°27’35.7” “ ( ZISP) ; 1 male, “ Korea, Gyeongsangnam-do, Hadong-gun, Bukcheon-myeon, Jikjeon-ri , Mt. Bongmyeongsan , light trap, 25.VII.2015, Deokseo Ku , Tae-Ho An ” ( SMNE) .

Description. Female. Body length 1.6–1.7 mm; fore wing length 1.3–1.5 mm.

Head 1.8–2.0 × wider than medial length (dorsal view), approximately as wide as mesoscutum. Occiput distinctly evenly concave. Head behind eyes distinctly roundly narrowed; transverse diameter of eye 2.0–2.5 × longer than temple (dorsal view). Ocelli arranged in triangle with base 1.1 × its sides. POL 1.2–1.3 × Od, 0.4–0.5 × OOL. Eye 1.4–1.5 × as high as broad. Malar space 0.8–1.0 × basal width of mandible, 0.15–0.20 × height of eye. Face weakly convex, its width 1.2 × median height, almost equal to height of eye. Tentorial pits distinct, distance between pits almost equal to distance from pit to eye. Clypeus high and weakly convex, its width 1.6–2.0 × median height, 0.7 × width of face; its lower margin weakly concave medially. Head distinctly roundly narrowed below eyes (front view).

Antenna with 21 antennomeres, thickened, setiform, its submedial antennomeres very weakly elongate or subsquare. Scape 2.0–2.4 × longer than wide. First flagellomere 2.1–2.2 × longer than its apical width, 1.15–1.20 × longer than second flagellomere. Tenth antennomere 1.0–1.1 × longer than its maximum width. Penultimate flagellomere 1.5–2.0 × longer than its width, 0.7–0.8 × as long as weakly acuminate apical flagellomere; the latter apically with distinct narrow spine.

Mesosoma 1.4–1.5 × longer than its maximum height. Mesoscutum highly and curvedly elevated above pronotum (lateral view), 1.5–1.7 × wider than its medial length (dorsal view). Prescutellar depression (scutellar sulcus) short and shallow, with distinct numerous carinae. Scutellum almost as long as anterior width. Prepectal carina present only laterally. Precoxal sulcus distinct, long, oblique, sinuate, subvertical anteriorly and subhorizontal posteriorly, extending almost along all mesopleuron length, crenulate.

Wings. Fore wing 2.5–2.6 × longer than its maximum width. Pterostigma 3.0–3.5 × longer than its maximum width. Metacarp (1-R1) sclerotised at most basal part, only shortly desclerotised distally, its sclerotised part 0.8–0.9 × as long as pterostigma. Radial vein (r) arising from anterior 0.3–0.4 of pterostigma; first radiomedial vein (2- SR) arising from radial vein (r) very closed to pterostigma. Present two abscissae of radial vein: very short first (r) and long second (3-SR); second abscissa (3-SR) distinctly curved, at least weakly sclerotised in basal 0.4 and desclerotised on remaining part, reaching as track distal margin of wing. Radial (marginal) cell weakly shortened, ~ 2.8 × longer than its maximum width. First radiomedial vein (2-SR) 8.5–10.0 × longer than recurrent vein (m-cu). Recurrent vein (m-cu) distinctly postfurcal to first radiomedial vein (2-SR), weakly divergent with basal vein (1-M) posteriorly. Discoidal (discal) cell shortly sessile anteriorly, 1.4–1.5 × longer than its maximum width. Nervulus (cu-a) weakly postfurcal, distance between basal vein (1-M) and nervulus (cu-a) 0.3–0.4 × nervulus (cu-a) length. Hind wing 3.3–3.5 × longer than its maximum width. First abscissa of mediocubital vein (M+CU) 2.0–2.5 × longer than second abscissa (1-M).

Legs. Hind coxa rather long and wide, 1.4–1.7 × longer than its maximum width, 1.1–1.3 × longer than propodeum (lateral view). Hind femur ~ 3.3 × longer than its maximum width. Hind tibia claviform, 3.9–4.3 × longer than maximum width, only weakly narrower than hind femur; longest inner tibial spur 0.7 × length of hind basitarsus. Hind tarsus ~ 0.9 × as long as hind tibia, at least first and second segments with distinct transparent ventral keel; its basitarsus 0.6–0.7 × as long as second–fifth segments combined; second segment 0.4 × as long as basitarsus, 1.2 × longer than fifth segments (excluding pretarsus).

Metasoma 0.9–1.0 × as long as mesosoma, its tergites rather weakly sclerotised. First and second sutures almost indistinct. First tergite with distinct, wide and oval median depression in basal 0.5–0.6; tergite 0.4–0.5 × as long as its apical width, 0.8–1.0 × as long as second tergite. Length of first to third tergites combined almost equal to their maximum width. Third tergite almost straight on posterior margin. Hypopygium distinctly acuminated distally (lateral view). Ovipositor sheaths widened distally, short, 0.6–0.8 × as long as hind basitarsus.

Sculpture. Vertex and frons of head densely areolate-punctate, face laterally widely curvedly striate, but sometimes striae fine, face sparsely punctate medially, clypeus densely and finely punctate, smooth between punctures. Mesoscutum densely and distinctly punctate; scutellum less distinctly punctate. Mesopleuron smooth in upper posterior half, mainly finely and rather sparse punctate in lower anterior half; metapleuron mainly smooth. Propodeum with areas distinctly delineated by carinae, with large and inversely-pentagonal areola, elongated basolateral and subhexagonal apico-lateral areas, petiolate area short and triangular; propodeum almost entirely smooth, only partly with fine punctation. Metasoma mainly smooth, first tergite finely or distinctly rugulose-striate in basomedian cavity.

Colour. Body mainly light reddish brown, metasoma medially widely yellow, infuscate anteriorly and posteriorly. Antenna light brown in basal 0.5–0.6, brown to dark brown in apical 0.4–0.5. Palpi pale yellow. Legs mainly light reddish brown, all trochanters, fore tibia basally and sometimes fore tarsus (except dark fifth segment) yellow to pale yellow. Fore wing hyaline or subhyaline in wide basal and apical areas, with distinct oblique infuscate band under pterostigma and to brachial (subdiscal) cell. Pterostigma brown, yellow or pale yellow basally and shortly apically; parastigma pale yellow or yellow.

Male. Body length 1.6 mm; fore wing length 1.5 mm. Antenna with 21 antennomeres, evenly setiform, without widened median antennomeres, 1.2 × longer than body. First flagellomere 2.0 × longer than its apical width, 1.1 × longer than second flagellomere. Tenth antennomere 1.45 × longer than its maximum width. Penultimate flagellomere 2.5 × longer than its width. Otherwise similar to female.

Etymology. This species is named after the former generic name Myriola , currently synonymised with Adelius , because this species has wing venation similar to this generic name, i.e., with the first radiomedial vein (2-SR) arising from the same point as the radial vein (r) or directly from the radial vein (r).

Comparative diagnosis. This new species belongs to the Adelius group of species having the first radiomedial vein (2-SR) arising from the same point of pterostigma as radial vein (r) or directly from radial vein (r) and is most similar to A. aridus ( Tobias, 1967) from Turkmenistan ( Tobias 1967). However, A. myriolus sp. nov. differ from the latter by having the propodeum with complete areas delineated by high carinae and entirely smooth between carinae (areas only partly delineated by high carinae and propodeum rugose-reticulate at least in basal half in A. aridus ), medial flagellomeres of antenna subsquare (weakly elongate in A. aridus ), pterostigma mainly brown and pale brown or yellowish basally (entirely dark brown in A. aridus ), segments of hind tarsus short and thickened (long and slender in A. aridus ), and the hind leg yellow (dark reddish brown in A. aridus ).

The new species is also similar to the Central American A. gauldi Shimbori et Shaw, 2019 from Costa Rica ( Shimbori et al. 2019), but it differs from the latter by the antenna setiform with distinctly narrow and elongate their apical flagellomeres (almost filiform and with wide and subsquare their apical flagellomeres in A. gauldi ), sculpture in basomedial cavity of the first tergite present (absent in A. gauldi ), the different types of the propodeum areolation and coloration of the antenna and legs, and species distribution (Eastern Palaearctic versus Neotropics).

Host. Unknown.

Distribution. Korean Peninsula.

Figures

FIGURE 3. Adelius myriolus sp. nov. (female, holotype). (A) Habitus, lateral view. (B) Head, front view. (C) Head and mesoscutum, dorsal view. (D) Antenna. (E) Apical part of antenna. (F) Head and mesosoma, lateral view. (G) Mesosoma and first metasomal tergite, dorsal view. (H) Hind leg, dorsal view. (I) Hind leg, lateral view.

FIGURE 4. Adelius myriolus sp. nov. (female, holotype).(A) Wings.(B) Propodeum and metasoma, dorsal view.(C) Propodeum and metasoma, lateral view.