Diaparsis (Diaparsis) alpha Khalaim & Villemant, 2021

Khalaim, Andrey I. & Villemant, Claire, 2021, Tersilochinae (Hymenoptera: Ichneumonidae) of Papua New Guinea: genus Diaparsis Förster, part 2. Species with notaulus, Zootaxa 5016 (1), pp. 56-80 : 58

1. Diaparsis (Diaparsis) alpha Khalaim & Villemant , sp. nov.

( Figs 1–3 )

Material examined. Holotype female ( MNHN) PNG, Madang Prov., Mt. Wilhelm (-5.759269, 145.2356), 1700 m, 25–27.X.2012, leg Valeba, Tulei, Novotny, Leponce, understorey; FIT-MW1700D-1/8-d01, P1902-15374.

Description. Female. Body length 3.8 mm. Fore wing length almost 2.8 mm.

Head roundly constricted behind eyes in dorsal view ( Fig. 1 ); gena 0.65× as long as eye width. Clypeus about twice as broad as long, lenticular, separated from face by distinct impression, smooth in lower half, scabrous and dull in upper half, with very fine sparse punctures in upper part; clypeus weakly and evenly convex in lateral view. Mandible slender, slightly constricted in basal half; upper tooth distinctly longer than lower tooth. Malar space about as long as basal mandibular width. Antennal flagellum ( Fig. 2 ) basally slender, with 13 flagellomeres; second flagellomere about 2.5× as long as broad; subapical flagellomeres somewhat elongate; flagellomeres 4 and 6 bearing thin and long subapical finger-shaped structures on outer surface (in flagellomere 5 this structure probably present but indiscernible in light microscope, or broken). Face weakly convex, without distinct median prominence. Face, frons and vertex finely granulate, dull, impunctate. Gena subpolished, weakly shining, without distinct punctures. Occipital carina complete, evenly arcuate in dorsal view.

Mesosoma finely and shallowly granulate, dull to weakly shining, impunctate. Notaulus distinctly impressed ( Fig. 1 ), with weak irregular wrinkles in notaular groove. Scutellum with lateral longitudinal carinae present in basal 0.1. Foveate groove extending in anterior 0.6 of mesopleuron, strongly oblique, straight, deep and sharp, with distinct transverse wrinkles. Propodeum with weak basal keel which is 0.65× as long as apical area. Propodeal spiracle separated from pleural carina by almost 2.0× diameter of spiracle. Apical area flat, rounded anteriorly; apical longitudinal carinae reaching transverse carina anteriorly.

Fore wing with second recurrent vein (2m-cu) postfurcal, weakly pigmented in anterior part, distinct posteriorly. First abscissa of radius (Rs+2r) straight, longer than width of pterostigma. First and second sections of radius (Rs+2r and Rs) meeting at right angle. Intercubitus (2rs-m) short and thick. Metacarpus (R1) almost reaching tip of the wing. Second abscissa of postnervulus (Cu&2cu-a) weak and short, thus brachial cell is partly open posteriorly. Hind wing with nervellus (cu1&cu-a) weakly reclivous. Legs slender.

First tergite 3.2× as long as posteriorly broad, slightly trapeziform in cross-section centrally, smooth dorsally and with petiole striate laterally, without distinct glymma; in dorsal view, petiole with lateral margins subparallel, and postpetiole rather strongly and evenly widened towards apex; upper margin of tergite, in lateral view, weakly arcuate in basal 0.7 and somewhat stronger arcuate in apical 0.3. Second tergite 1.25× as long as anteriorly broad. Thyridial depression deep, about 1.5× as long as broad, with posterior end rounded. Ovipositor robust and very short, upcurved, as long as apical depth of metasoma, with weak dorsal subapical depression ( Fig. 3 ); sheath 0.4× as long as first tergite.

Head, mesosoma and first segment of metasoma black; clypeus brownish in lower 0.4. Palpi and mandible (except red teeth) yellow. Scape and pedicel of antenna yellow-brown, dorsally darker; flagellum predominantly black with basal flagellomeres brownish. Tegula and pterostigma brown. Wings hyaline. Legs predominantly brown; fore partly yellowish. Metasoma posterior to first tergite predominantly dark brown, with distal end yellow ( Fig. 3 ).

Male. Unknown.

Etymology. The species is named after the first letter of the Greek alphabet (alpha).

Distribution. Papua New Guinea.

Comparison. Diaparsis alpha sp. nov. may easily be distinguished from all its Oriental and Oceanic congeners by its exceptionally short, robust and strongly upcurved ovipositor ( Fig. 3 ).

Figures

FIGURES 1–8. Diaparsis alpha sp. nov., holotype, female: 1—head and mesoscutum, dorsal; 2—head with antenna, lateral; 3—apex of metasoma with ovipositor, lateral. Diaparsis beta sp. nov., holotype (6, 7) and paratype (4, 5, 8), females: 4—head and mesoscutum, dorsal; 5—head, front; 6—antenna, lateral; 7, 8—propodeum, dorso-posterior.