Benyllus rufostriatus, Riedel, 2023

Riedel, Matthias, 2023, Contribution to the knowledge of the Ichneumoninae (Hymenoptera, Ichneumonidae) from Maritime Southeast Asia, Zootaxa 5363 (1), pp. 1-94 : 28-30

Benyllus rufostriatus nov. sp.

( Figs 10A–D )

Holotype. (♀) West-Sumatra, Maninjau lake , 0°16´13.76´´S 100°13´57.96´´E, 19.xi.2015, leg. V. Gromenko (coll. Riedel).

Paratype. (♀) similar label (coll. Riedel).

Etymology. The species name refers to the red-banded basal tergites.

Description. ♀. Body length 8.8–9.6 mm.

Head. Flagellum with 34–36 flagellomeres, slightly lanceolate; 1 st flagellomere 4.4 × longer than wide, about 14 th flagellomere square, widest flagellomeres 1.2–1.3 × wider than long. Temple very short, strongly and linearly narrowed behind eye, dorsally 0.1 × as long as eye (fig. 10B). OED 1.0 × and OOD 0.8 × ocellar diameter. Frons shining, with some fine superficial punctures. Face rather densely punctate, shining, slightly impressed above anterior tentorial pits, laterally as side of clypeus slightly swollen (fig. 10A). Clypeus with sparse punctures, apical margin sharp and straight. Mandible long, and distinctly narrowed behind base, with two teeth, lower tooth smaller. Malar space 1.0 × as long as width of mandibular base. Gena with sparse fine punctures. Genal carina reaching hypostomal carina close to mandibular base.

Mesosoma . Notaulus indistinct. Mesoscutum finely and densely rugose-punctate, posterior margin ± with longitudinal striae, dull. Mesopleuron with fine superficial punctures, shining; speculum smooth. Epicnemial carina low, dorsally reaching frontal margin of mesopleuron. Metapleuron with rather dense superficial punctures; juxtacoxal carina present. Scutellum moderately elevated, slightly longer than wide, densely punctate and with complete lateral carina. Propodeum completely carinated, with distinct apophysis (fig. 10C); spiracle slit-shaped. Area basalis trapezoid, wider than long and with median tubercle. Area superomedia dome-shaped, slightly longer than wide; costula reaching at apical 0.8 of its length. Hind coxa with dense punctures, without scopa; hind femur densely punctate, 4.3–4.5 × longer than wide. Claws simple. Areolet pentagonal, frontal distance between veins 2rsm and 3rs-m 3.0 × their diameter. Vein 1cu-a slightly antefurcal by 1.0 × its width.

Metasoma. Oxypygous. Petiole about as wide as high. Postpetiole slightly widened, without latero-median carina; median field not separated, finely aciculate; lateral field striate and punctate. Gastrocoelus small, much longer than wide. Thyridium very small, pit-shaped (fig. 10D). 2 nd tergite 1.1 × wider than long, with fine very dense punctures, dull. Following tergites with superficial punctures, ± shining. 2 nd to 5 th sternites with median folds. Ovipositor sheath narrow, reaching widely behind metasomal apex by length of 2 nd hind tarsomere.

Colour. Head black; palp, clypeus, face, frontal orbit up to vertex (widened dorsally) ivory. Mandible reddish. Antenna black; scape ventrally and basal flagellomere red, flagellomeres 7–15 with ivory stripes. Mesosoma red; collar and spot of subtegular ridge ivory. Mesoscutum except reddish margins and spots on area externa of propodeum blackish. Petiole red; postpetiole blackish, with wide red apical band. 2 nd to 3 rd tergite black, with wide apical red bands; 4 th tergite red, with black basal spot; following tergites reddish. Ovipositor sheath black. Legs red; hind femur black in apical 0.4; hind tibia reddish-yellow, black in apical half; mid tarsus brown, hind tarsus black. Wings hyaline; pterostigma blackish, with paler margins.

♂ unknown.

Remarks. This new species runs to Benyllus rufopictus Heinrich in his key ( Heinrich 1934: 159–160), but differs from this (and other Indonesian) species by its reduced ivory coloration and black/red banded basal tergites.

Distribution. Only known from Sumatra.

Figures

FIGURE 10. Benyllus rufostriatus n. sp. HT ♀. A face, frontal view, B head, dorsal view, C propodeum, dorsal view, D basal tergites, dorsal view.