Description and notes
Identification keys and general biology are given in Krombein (1967), Morgan (1984) and Kunz (1994). Great care must be taken when distinguishing this species from O. puncticollis.
Devon to Kent and north to North Yorkshire.
Europe (including Norway, Sweden, Finland, Denmark, The Netherlands, Belgium, France, Spain, Germany, Italy, Poland, Hungary), north Africa, western Asia and North America.
Status (in Britain only)
This species is not regarded as being scarce or threatened.
Found in the open habitats of its stem and wood-nesting hosts.
May to August but usually during July, rarely during May.
Bird’s-foot-trefoil, hogweed and knotweeds.
No information available.
A brood parasite on species of Crabonidae, subfamily Pemphredoninae, including the genera Psen, Psenulus, Pemphredon, and Passaloecus. The parasite overwinters as a diapausing larva, pupating in the late spring.