Aivalykus microaciculatus Ranjith et Belokobylskij, 2020

Ranjith, A. P., Belokobylskij, Sergey A., Sureshan, P. M. & Nasser, M., 2020, The genus Aivalykus Nixon, 1938 (Hymenoptera: Braconidae: Doryctinae) with description of a new species from India and Arabian Peninsula, Zootaxa 4822 (2), pp. 269-276 : 271-275

Aivalykus microaciculatus Ranjith et Belokobylskij , sp. nov.

( Fig. 1–3 )

urn:lsid:zoobank.org:act:C4D670CB-F1DE-4878-813C-452380DD1011

Type material. Holotype, female, “ INDIA: Maharashtra Wildlife Sanctuary, Lonar Crater, Buldhana Dist. , 19.xi.2003, coll. Sureshan P.M. ” ( ZSIK).

Paratypes: 1 female with same data of holotype ( DZUC) ; 1 male, “ INDIA: Kerala, Malappuram, Calicut University Botanical Garden , malaise Trap, 29.iii–12.iv.2016, col. Ranjith A.P. ” ( DZUC) ; 3 females, 2 males, “United Arab Emirates, Hatta (6394), at light, 19–28.iii.2006, 24˚49’ N 56˚07’ E, A. v. Harten, RNMH’06” ( RMNH, ZISP) .

Description. Female. Body length 2.0 mm; fore wing length 1.5 mm; ovipositor sheath length 1.3 mm.

Head. Head width 1.4 × its median length. Temple roundly narrowed behind eye; transverse diameter of eye 1.6 × length of temple. Ocelli small, arranged in equilateral triangle with base as long as its sides. POL 1.33 × Od, 0.2 × OOL. Eye glabrous, 1.3 × as high as broad. Malar space 0.4 × height of eye, 0.6 × basal width of mandible. Face width almost equal to height of eye and 1.2 × height of face and clypeus combined. Malar suture absent. Clypeal suture shallow, but distinct, interrupted medially. Hypoclypeal depression round, its transverse width 0.9 × distance from edge of depression to eye, 0.3 × width of face. Occipital carina reduced below, not fused with the hypostomal carina. Antennae incomplete, with more than 15 antennomeres (missing apically). Scapus 1.4 × longer than its maximum width. First flagellomere not flattened, straight, 7.0 × longer than its apical width, 0.8 × longer than second flagellomere.

Mesosoma. Mesosoma 1.8 × longer than high. Neck of prothorax short. Pronotal carina distinct. Mesoscutum highly and almost perpendicularly elevated above pronotum. Notauli deep in anterior half, very shallow or almost absent in posterior half, anteriorly finely crenulate. Prescutellar depression (scutal sulcus) deep, with three longitudinal carinae, very finely rugulose to smooth between carinae, 0.3 × as long as scutellum. Subalar depression shallow, wide, very finely rugulose. Sternaulus shallow, smooth, connected with prepectal carina anteriorly, running along approximately half of lower part of mesopleuron.

Wings. Fore wing 3.25 × longer than its maximum width. Radial vein (r) arising almost from middle of pterostigma. Radial (marginal) cell not shortened. First radial abscissa (r) almost perpendicular to pterostigma, 1.3 × longer than maximum width of pterostigma, 0.75 × as long as first radiomedial vein (2-SR). Second radial abscissa (3-SR) weakly evenly curved, 6.0 × longer than first abscissa (r), 4.6 × longer than first radiomedial vein (2-SR). Discoidal (first discal) cell 2.3 × longer than wide. Recurrent vein (m-cu) antefurcal, 2.6 × longer than second abscissa of medial vein (2-SR+M). Brachial (first subdiscal) cell narrow, gently closing apically distinctly before recurrent vein (m-cu). Distance from nervulus (cu-a) to basal vein (1-M) about 2.0 × nervulus (cu-a) length. In hind wing medial (basal) cell closed anterodistally.

Legs. Hind femur 4.0 × longer than wide. Hind tarsus as long as hind tibia. Hind basitarsus 0.85 × as long as second–fifth tarsomeres combined. Second tarsomere 0.45 × as long as basitarsus, about 2.0 × longer than fifth tarsomere (without pretarsus).

Metasoma. Metasoma 1.1 × longer than head and mesosoma combined. First tergite without spiracular tubercles (spiracles situated on basal 0.3 of tergite), distinctly and linearly widened from base to apex. Maximum width of first tergite 1.65 × its width at level of dorsope; length 0.85 × its apical width. Second tergite without depressions, length of tergite 0.6 × its basal width, 1.4 × length of third tergite. Second suture shallow and almost straight. Ovipositor sheath 0.65 × as long as body, 1.2 × longer than metasoma, 1.9 × longer than mesosoma, 0.86 × as long as fore wing.

Sculpture and pubescence. Vertex and frons micro-aciculate; temple smooth; face very finely and sparsely rugulose-striate, medially smooth, laterally coriaceous. Sides of pronotum almost entirely smooth. Mesoscutum distinctly coriaceous, with mid longitudinal carina in posterior third. Scutellum coriaceous, glabrous medially. Mesopleuron mainly smooth, coriaceous medially. Metapleuron smooth, posteriorly rugulose. Propodeum mainly smooth, with fine and short rugulosity along carinae, with median carina in basal half, with distinctly delineated by carinae, long, relatively wide and striate areola in posterior half of propodeum; lateral carina complete and rather strong. Hind femur coriaceous. First metasomal tergite with distinct and complete dorsal carinae, densely and rather finely striate, smooth medially and medioposteriorly. Remaining tergites completely smooth. Hind tibia on dorsal surface with rather sparse and semi-erect setae, length of these setae 0.7–0.8 × maximum width of hind tibia.

Colour. Body mainly light reddish brown with yellow areas; flagellomeres, ocellar area, eyes, lateral lobes of mesoscutum entirely and middle lobe anteriorly, mesopleuron, pterostigma in apical half, second metasomal tergite, tip of ovipositor and ovipositor sheath brownish yellow to dark brown.

Variation. Body length 2.0– 2.3 mm; fore wing length 1.5–1.7 mm; ovipositor sheath length 1.3–1.4 mm. Head width 1.4–1.5 × its median length. POL 1.2–1.4 × Od, 0.2–0.4 × OOL. Malar space 0.6–0.8 × basal width of mandible. Hypoclypeal depression transverse width 0.8–0.9 × distance from edge of depression to eye, 0.3–0.4 × width of face. Antennae with 18-antennomeres, 0.9 × as long as body. Scapus 1.4–1.5 × longer than its maximum width. First flagellar segment 5.5–7.0 × longer than its apical width, 0.80–0.85 × longer than second segment. Penultimate segment 3.8 × longer than maximum width, 0.6 × as long as first flagellar segment, 0.9 × as long as apical segment; the latter acuminate apically. Mesosoma 1.8–1.9 × longer than high. Notauli deep in anterior third or half. Scutellum and mesopleuron sometimes entirely smooth. Fore wing 3.2–3.6 × longer than its maximum width. First radial abscissa (r) 1.3–1.4 × longer than maximum width of pterostigma, 0.70–0.75 × as long as first radiomedial vein (2- SR). Second radial abscissa (3-SR) 6.0–6.5 × longer than first abscissa (r), 4.5–4.6 × longer than first radiomedial vein (2-SR). Discoidal (first discal) cell 2.0–2.3 × longer than wide. Recurrent vein (m-cu) 2.0–2.6 × longer than second abscissa of medial vein (2-SR+M). Distance from nervulus (cu-a) to basal vein (1-M) 1.5–2.0 × nervulus (cu-a) length. Hind femur 3.6–4.0 × longer than wide. Hind basitarsus 0.75–0.85 × as long as second–fifth tarsomeres combined. Second tarsal segment 0.35–0.45 × as long as basitarsus, 1.5–2.0 × longer than fifth tarsomere (without pretarsus). Metasoma 1.1–1.2 × longer than head and mesosoma combined. Maximum width of first tergite 1.6–1.7 × its width at level of dorsope; length 0.80–0.85 × its apical width; sometimes with dorsal carinae only in basal half. Length of second tergite 0.6–0.9 × its basal width, 1.4–1.9 × length of third tergite. Ovipositor sheath 0.60–0.65 × as long as body, 1.1–1.2 × longer than metasoma, 1.9–2.0 × longer than mesosoma, 0.8–0.9 × as long as fore wing. Sometimes head dorsally, mesoscutum, scutellum and mesopleuron brown or reddish brown; pterostigma light brown in apical half.

Male. Body length 1.6–3.0 mm; fore wing length 1.05–1.85 mm. Nervulus (cu-a) only weakly postfurcal. Hind femur wider, 3.0–3.1 × longer than wide. Metasoma very long, strongly narrowed behind third tergite, then almost parallel-sided and depressed; 1.5–1.8 × longer than mesosoma and head combined. First metasomal tergite longer, its length 0.9–1.1× apical width. Basal four antennomeres yellow, then brown to dark brown. Body yellow except eyes, second metasomal tergite dorsally and wing veins brown; sometimes mesosoma mainly reddish brown.

Etymology. Named after very thin and dense aciculation of vertex.

Distribution. India (Kerala and Maharashtra), United Arab Emirates.

Host. Emerged from unidentified beetle larvae infesting fig tree in India.

Remarks. This new species is the most peculiar within Aivalykus based on the micro-aciculate sculpture of vertex. Most of other species have the vertex transversely striate or smooth. Aivalykus microaciculatus sp. nov. differs from one of the species described from India and rather widespread A. eclectes Nixon in having fore wing recurrent vein (m-cu) antefurcal (vs interstitial in A. eclectes ). This new species is also similar to Oriental A. nitidus ; the differences between them are showed in the key provided above. Aivalykus microaciculatus sp. nov. comes close to Neotropical A. flavus in having second metasomal tergite smooth, but it differs from it in having vertex densely micro-aciculate (vs smooth in A. flavus ), propodeum with areola distinctly delineated by carinae (vs indistinct areola in A. flavus ) and fore wing nervulus (cu-a) postfurcal (vs interstitial in A. flavus ).

Figures

FIGURE 1. Fore and hind wing of Aivalykus microaciculatus Ranjith et Belokobylskij, sp. nov. (paratype, female). 1. Radial (marginal) cell, 2. Discoidal (first discal) cell, 3. Brachial (first subdiscal) cell, 4. Medial (basal) cell of hind wing.

FIGURE 2. Aivalykus microaciculatus Ranjith et Belokobylskij, sp. nov. (holotype, female).A. Habitus, lateral view. B. Head, anterior view. C. Head, dorsal view. D. Mesosoma, lateral view. E. Head and mesosoma, lateral view. F. Propodeum, dorsal view.

FIGURE 3. Aivalykus microaciculatus Ranjith et Belokobylskij, sp. nov. (holotype, female). A. First and second metasomal tergites, dorsal view. B. Second to six metasomal tergites, dorsal view. C. Wings. D. Male habitus, in lateral view.