Dichrogaster modesta (Gravenhorst, 1829)

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 : 90

Dichrogaster modesta (Gravenhorst, 1829)

Dichrogaster spp. are small Phygadeuontinae that can be recognised by their clypeus (very small) and their propodeum (very short, with its area superomedia defined by sharp carinae and measuring about three times as wide as long) ( TOWNES, 1970a).

The taxonomical status of this taxon is not entirely clear, but at the moment of writing it is still accepted as a valid species. HORSTMANN, 1991 stated it could be a variation of Dichrogaster aestivalis (Gravenhorst, 1829) but is not able to analyse it decisively. He proposes it is best to accept both species out of practical reasons (which we do now). Both species have a typical wing venation, with their mesoscutum coriaceous and more or less matt, and their mesopleuron shiny without many punctures (HORSTMANN, 1976). D. modesta , however, has a second tergite that is entirely red. Its metapleuron is more distinctly punctuated dorsally (HORSTMANN, 1991). It has been reported as a parasitoid of several beetles and green lacewings ( YU et al., 2012).

First report for the Netherlands; unreported in Belgium.

MATERIAL EXAMINED:

THE NETHERLANDS: • 1 ♀; Drachten-Azeven (FR); 53°06’49”N 6°09’02”E; 19/vii/2020; H. Meijer leg.; coll. HM; field observation; H. Meijer det. • 1 ♀; Almere (FL); 52°22’49”N 5°14’13”E; 25/vii/2020; P. Hoekstra leg.; coll . PH; field observation; M. Schwarz, P. Hoekstra & F. Verheyde det. (ObsID: 197700635) .