Perithous septemcinctorius (Thunberg, 1822)

Perithous septemcinctorius belongs to the subgenus Hybomischos Baltazar, 1961, which is sometimes treated as a valid genus name (Fitton et al., 1988). The species has a Holarctic distribution, and P. fuscipennis is already known as its host (Fitton et al., 1988). Additionally Aubert (1969) recorded it as a hymenopterous parasite for Andricus (Cynipidae), Pemphredon, Psen, Psenulus (Crabronidae) and listed Omalus as a possible host (Torgersen, 1972). The present study confirms Aubert’s intuition. As in the case of M. acasta, P. septemcinctorius attacked both P. fuscipennis (2.1 % of cells) and O. sculpticollis (4.5 % of cocoons).