Oligoneurus Szépligeti, 1902

Belokobylskij, Sergey A., Vasilenko, Dmitry V. & Perkovsky, Evgeny E., 2024, The first record of the highly derived genus Oligoneurus Szépligeti, 1902 (Hymenoptera, Braconidae, Ichneutinae, Muesebeckiini) from Eocene Danish amber with description of a new species, Ecologica Montenegrina 71, pp. 292-299 : 293-294

Genus Oligoneurus Szépligeti, 1902

Type species. Oligoneurus concolor Szépligeti, 1902 , by monotypy and original designation.

Diagnosis of the genus. Head. Occipital carina absent; malar space short to very short; malar suture always present. Maxillary palpus 5-segmented, second segment distinctly widened; labial palpus 4 or 3- segmented, second segment widened. Antenna usually filiform, with 13–30 segments. First flagellar segment without multiparous plate-like sensillae (rhinaria). Mesosoma. Pronotum without dorsolateral pit (subpronope). Notauli often completely absent, but sometimes present only in basal vertical one– third of mesoscutum. Prescutellar depression short and sculptured. Posterior scutellar depression and prepectal carina absent. Precoxal sulcus absent or sometimes present, but very shallow, sculptured or smooth. Propodeum usually smooth, but sometimes areolate to areolate-rugose. Wings venation strongly reduced. In fore wing, basal vein (1-M) mostly straight but its anterior portion strongly and abruptly curve forwards. Incomplete discoidal (discal) cell sessile anteriorly on parastigma. Metacarp (1-R1) incomplete, absent distally, long or short. Distinctly sclerotised only basal vein (1-M), first radial abscissa (r) and first abscissa of medial vein (1-SR+M). Absent or strongly desclerotised: distal parts of radial (SR1), first and second radiomedial (2-SR and r-m), recurrent (m-cu), distal abscissa of medial (2-M) and parallel (CU1a) veins; also absent veins on distal and posterior parts of brachial (subdiscal) cell. Longitudinal anal vein (1-1A) of hind wing complete, reaching sclerotised nervellus (cu-a); its submedial (subbasal) cell closed distally. Legs. Hind coxa large. Hind tarsal claw simple. Metasoma. First tergite with or without longitudinal lateral carinae, usually mostly smooth, with or without margined median longitudinal depression, often narrow distally behind spiracles. Second tergite with two strongly divergent posteriorly and narrow sublateral furrows. Seventh tergite of male setose and without lateral pits (tergal gland openings), with large medial excavations on sixth and seventh tergites. Female hypopygium pointed distally, without dense patch of setae apically.

Hosts. Parasitoid of the lepidopteran leaf-miners Bucculatrix sp. ( Bucculatrigidae ), Cosmopterix phyllostachysea Kuroko, 1975 ( Cosmopterigidae ), and Desmia benealis Schaus, 1920 ( Crambidae ).

Distribution. Neotropical, Oriental, and Palaearctic regions.