BTB Stenichneumon culpator (Schrank, 1802)
Family: Ichneumonidae, (Ichneumon wasps)
Body length: 15 to 16mm
This Ichneumon wasp is widespread over most of Europe, as far south as southern Spain and over much of Great Britain (Scarce into the midlands and further north). It mainly preys on small insects, and can also be seen feeding on flower heads for nectar and pollen. Like most other Ichneumon wasps, they parasite lepidoptera larvae.
Habitat: Woodland edges, hedgerows and grasslands.
Adults on the wing from April till September.
There are three similar species (and the images below could be one of these, that’s why I have put BTB)