Coleocentrus soleatus (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 : 25

Coleocentrus soleatus (Gravenhorst, 1829) (Fig. 3 A–B)

Coleocentrus spp. are large parasitoids, which can be recognised within the subfamily by their areolet (triangular) and clypeus (with a median apical tubercle). Ovipositor is 2.0–3.5 as long as hind tibia ( VARGA, 2013).

Both males and females of C. soleatus have red hind trochanters and trochantelli with black colouration (Fig. 3 A). Females at least have their fore trochanters reddish. The tarsomeres of the males are only partly white (admittingly, this is more difficult to see on photographic evidence) and the clypeus is completely yellow (Fig. 3B). This distinguishes it from the common Coleocentrus excitator (Poda, 1761) . C. soleatus is a presumably (very) rare species in Western Europe, known from only a few records, with Germany being the closest country to Belgium and the Netherlands. It seems highly probable the species has only recently expanded its territory from Eastern and Central Europe, thereby following many other ichneumonid wasps related to the presence of dead wood and forest areas (see VERHEYDE et al., 2020a). Hosts are unknown ( VARGA, 2013). First report for Belgium and the Netherlands.

MATERIAL EXAMINED:

BELGIUM: • 2 ♀♀; Somal (NA); 25/v/2012; P-N. Libert leg.; coll. PNL; field observation; P- N. Libert det. • 1 ♂; Somal (NA); 18/v/2013; P-N. Libert leg.; coll. PNL; field observation; P- N. Libert det. • 1 ♂; Londerzeel (VB); 50°59'15"N 4°16'19"E; 20/iv2020; S. De Rycke leg.; coll. SDR; field observation; F. Verheyde det. (ObsID: 193762942) ; Fig. 3A–B . • 1 ♂; Anderlecht , centrum (BR); 50°50'06"N 4°16'60"E; 22/iv/2020; M. Marblie leg.; field observation; O. Varga & F. Verheyde det. (ObsID: 193762942) . • 1 ♀; Hody (LG); 50°29’05”N 5°30’39”E; 7/v/2020; A. Derouax leg.; field observation; F. Verheyde det. (ObsID: 190791292) […].

THE NETHERLANDS: • 1 ♀; Udenhout , De Brand (NB); 51°37'35"N 5°06'29"E; 3/v/2020; J. van de Heuvel leg.; field observation; F. Verheyde det. (ObsID: 190311894) . • 1 ♀; Vlijmen , Bosje Hooge Bank (NB); 51°40’14”N 5°12’03”E; 8/vi/2020; H. van der Sterren leg.; field observation; F. Verheyde det. (ObsID: 193565619) .