Allonotus rufiventris, Riedel, 2023

Riedel, Matthias, 2023, Contribution to the knowledge of the Ichneumoninae (Hymenoptera, Ichneumonidae) from Maritime Southeast Asia, Zootaxa 5363 (1), pp. 1-94 : 11-13

Allonotus rufiventris nov. sp.

( Figs 3A–D )

Holotype. (♀) Indonesia: N Sumatra, Ketambe , c 400 m, near N.P. Gn. Leuser, Mal. trap, xi.1994, Y. v. Nierop & C. van Achterberg, RMNH´95 (Leiden).

Paratypes. (♂) Indonesia: N Sumatra, Ketambe , c 400 m, near N.P. Gn. Leuser, Mal. trap, vii.1994, Y. van Nierop & C. van Achterberg, RMNH´95; (2 ♀♀) Indonesia: N Sumatra, Aceh, Ketambe , 400 m, viii.1995, Mal. trap, nr edge rainforest, leg. Y. van Nierop & C. van Achterberg, RMNH´99; (♀) Indonesia: N Sumatra, Aceh, Ketambe , 400 m, x.1995, Mal. trap, nr edge rainforest, leg. Y. van Nierop & C. van Achterberg, RMNH´99; (♂) Indonesia: N Sumatra, Aceh, Ketambe , 400 m, v.1995, Mal. trap, nr edge rainforest, leg. Y. van Nierop & C. van Achterberg, RMNH´99; (♂) Indonesia: N Sumatra, Aceh, Ketambe , 400 m, vi.1995, Mal. trap, nr edge rainforest, leg. Y. van Nierop & C. van Achterberg, RMNH´99 (all in Leiden and coll. Riedel) .

Etymology. The species name refers to the largely reddish metasoma.

Description. ♀: Body length 10.0– 12.5 mm.

Head. Flagellum with 38–41 flagellomeres, slender and slightly lanceolate; 1 st flagellomere 4.1–4.2 × longer than wide, widest flagellomeres 1.1–1.3 × wider than long. Temple short, strongly and roundly narrowed behind eye (fig. 3B). OED 1.6 × and OOD 0.7 × ocellar diameter. Temple with fine sparse punctures. Frons with microsculpture and fine very sparse punctures. Face with sparse superficial punctures. Clypeus large, moderately swollen baso-medially, slightly concave centrally, with sparse punctures; apical margin sharp, slightly rounded (fig. 3A). Mandible sickle-shaped, ventral tooth slightly smaller than dorsal tooth and completely turned inwards. Malar space 0.7 × as long as width of mandibular base. Gena with fine rather dense punctures. Genal carina reaching mandibular base.

Mesosoma . Notaulus impressed in frontal 0.3 of mesoscutum. Mesoscutum finely rugose-punctate, dull. Mesopleuron and metapleuron with fine superficial punctures, shining. Juxtacoxal carina present. Scutellum moderately elevated, longer than wide, with complete lateral carina. Propodeum completely carinated (fig. 3C), with blunt short apophysis. Area basalis with median ridge. Area superomedia hexagonal, c 1.5 × longer than wide, usually with median ridge; costula reaching at 4/10 of its length. Legs slender. Hind coxa densely finely punctate and pilose, without distinct scopa. Hind femur 4.1–4.2 × longer than wide. Claws simple. Areolet pentagonal; frontal distance of veins 2rs-m and 3rs-m 1-2 × their width. Vein 1cu-a interstitial or antefurcal by 1.0 × its width.

Metasoma. Slender, oxypygous. Postpetiole slightly widened, finely granulate but shining; median field not separated. Gastrocoelus indicated by longitudinal ridges. Thyridium transverse, separated from basal margin of 2 nd tergite by 2.0 × its length, 2.5–3.0 × wider than the interval between thyridia (fig. 3D). 2 nd tergite 1.2–1.4 × longer than wide. All tergites very finely rugose-punctate and dull; 2 nd tergite rugose-punctate basally. Ovipositor sheath long and slender, reaching behind metasomal apex by length of 7 th tergite.

Colour. Red. Scape black dorsally, red ventrally; flagellum black, flagellomeres 7–15/16 ivory. Clypeus and face yellowish or cream-yellow. Frons dorsally and temple frontally reddish-brown. Tergites reddish-yellow; postpetiole reddish-brown; 2 nd tergite basally and apically reddish-brown. Thyridium black. 3 rd tergite blackish basally, reddish-brown apically. Following tergites with diffuse reddish-brown suffusion. 7 th tergite with small yellowish or ivory apical spot. Legs red; mid tarsus brown; hind femur black, narrowly red basally; hind tibia black, sometimes with reddish basal spot; hind tarsus black. Wings hyaline; pterostigma brown.

♂. Body length 9.5–10.0 mm.

Head: Flagellum with 36 flagellomeres, bristle-shaped; 1 st flagellomere 4.0 × longer than wide. Tyloids indistinct, on flagellomeres 10–16, long-oval, maximally 0.7 × as long as their flagellomeres. Malar space 0.7 × as long as width of mandibular base. Hind femur 4.0–4.3 × longer than wide. 2 nd tergite 1.4–1.6 × longer than wide. Apical margin of hypopygium slightly rounded. Structure otherwise as described for the ♀. Colour reddish. Flagellomeres 10–16 ivory dorsally. 2 nd tergite with black thyridia and black apical margin. Coloration otherwise as described for the ♀.

Remarks. This new species is closely related to Allonotus rufus Cameron. It differs by wider thyridium, stouter 2 nd tergite, paler face and clypeus and a different coloration of metasoma.

Distribution. Only known from Sumatra.

Figures

FIGURE 3. Allonotus rufiventris n. sp. HT ♀. A face, fontal view, B head, dorsal view, C propodeum, dorsal view, D basal tergites, dorsal view.