11-15mm, about the size of a large bluebottle. It has yellow-orange side patches to the abdomen and a black zig-zag central band. Like all Tachinids it has numerous bristly hairs on the abdomen.

Various habitats.

Peak time is June to August.

The maggot stage of the fly develops inside the Dark Arches moth, eating it from within, and then emerging to pupate.

This species is distributed in the southern half of Britain, mainly in southern England and South Wales.

Rarely recorded in Leicestershire and Rutland.