Background
Carcelia iliaca (C. iliaca) is a parasitoid that is associated with Oak Processionary Moth (Thaumetopoea processionea; OPM).
C. iliaca parasitises older, almost full-grown OPM larvae inside or outside OPM nests and then completes its development by overwintering in a spent OPM nest before emerging the following spring.
Identification
C. iliaca:
- resembles a dark grey housefly or bluebottle-shaped fly
- has a body length of approximately eight-10 millimetres
- can be observed running over OPM nests and caterpillars
- can be found in the general vicinity of active OPM nests.
Where C. iliaca is observed on OPM nests, caterpillars may appear agitated.
Images of C. iliaca
Bottom picture: credit The Royal Parks
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