The gall fly Terellia tussilaginis is mainly pale greeny yellow in colour with distinctive brown banding on its wings.

The larva form galls in the achenes of Burdock (Arctium) flowerheads; the achene is swollen with a tiny entrance hole near the top and larger hole at base blocked by debris.  Pale-brown puparia are in the old flowerheads over winter

Tephritis bardanae also galls burdock

Adult Gall

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Around Burdock.

June to August.

The larvae feed on Burdock and cause galls to form.

Fairly frequent and widespread in southern Britain at least.

Fairly frequent in Leicestershire and Rutland