Allomacrus arcticus (Holmgren, 1880)

Verheyde, Fons, Hoekstra, Paul, Libert, Pierre-Nicolas, Meijer, Hilco, Ketelaere, Augustijn De, Vandaudenard, Thibaud, Belgers, Dick & Brosens, Edwin, 1880, Two hundred and five ichneumonid wasps reported for the first time in Belgium and the Netherlands (Hymenoptera: Ichneumonidae), Belgian Journal of Entomology 122, pp. 1-142 : 70

Allomacrus arcticus (Holmgren, 1880)

Cyllocerines can be recognised by a combination of a flattened clypeus, a rather elongate propodeum with median longitudinal carinae but no transverse carina, a granulate first tergite and well-defined notauli. Additionally, the males of Cylloceria sp. (see below) have very characteristic tyloids in the form of semi-circular excavations (Fig. 35 B). The females have long, notched ovipositors (BROAD et al., 2018).

A. arcticus belongs to a small genus. Its nervellus in the hind wing is inclivous and broken below the middle. The fore wing is less than 6 mm long. A. arcticus has a stumpy body, its clypeus is wide and flat without deep impression. Our male specimen also had longitudinal yellow spots running along the inner eye orbits ( HUMALA, 2002).

First report of the species and the genus for the Netherlands; unreported in Belgium.

MATERIAL EXAMINED:

THE NETHERLANDS: • 1 ♂; Tilburg , Leijbos (NB); 51°32’34”N 5°00’51”E; 23/iv/2020; IWG KNNV Tilburg leg.; coll . PH; malaise trap (16-23); P. Hoekstra & A. Humala det. (ObsID: 206464937) .