Wingspan 7-8 mm.
Distributed mainly in the south and east of England, this species frequents waste ground and similar habitats where its foodplant, mugwort (Artemisia vulgaris) is plentiful.
The moths occur in two generations, flying in May and in August, usually in the late afternoon.
The larva feeds initially in a gallery on the underside of a mugwort leaf, eventually forming a blotch or blister that becomes inflated and turns at first yellowish, and later purple.
Leafmine (British Leaf Mining Fauna)