A small orange-grey fly with dark spotted wings.  Although this species usually has more extensive darkening on the front margin of the wings it is very similar to other members of the group and  detailed examination is needed to determine to species level.  If this detailed examination has not taken place records should be added to the aggregate page.

The female ovipositor curves slightly upwards in lateral view, so the upper and lower halves are not symmetrical.

Opomyza petrei females have an ovipositor that is more or less symmetrical in lateral view.

Unless identified by a recognised expert, a photo is required and the specimen should be examined with a microscope. Specimens that have not been examined in this way should be recorded to the aggregate page.

Prefers moist habitats and can be found in grasses and leaf litter.

June to October.

Breeds in grass stems. Walks very slowly and is reluctant to fly.

Widespread and common in Britain.

Status in Leicestershire & Rutland not known.