Description and notes
Previously known as Omalus violaceus. Identification keys and general biology are given in Spooner (1954), Morgan (1984), Falk (1991) and Kunz (1994).
Scarce, from South Devon to Kent, and north to North-east Yorkshire.
Overseas, the wasp occurs in Europe (including Norway, Sweden, Finland, Denmark, The Netherlands, Belgium, Luxembourg, France, Spain, Germany, Italy, Poland, Hungary) and Asia (including Manchuria and Siberia).
Status in Britain and Ireland
This species was regarded as being Notable B (now Scarce B) by Falk (1991).
Often associated with gardens and habitats with dead wood including lowland heathland, coastal sand dunes, lowland wood pasture and parkland, fen marsh and swamp, and lowland dry acid grassland.
Usually June to August, sometimes May, rarely April and September.
No specific information found.
This species is a parasitoid of the larvae of small aerial-nesting crabonid wasps including Pemphredon lugubris and Passaloecus corniger.