Wingspan about 12 mm.  There are a number of very similar Coleophora species and adults need to be determined by examination of the genitalia. 

Adult   Cased Larva (or feeding signs)

Adult Coleophora need to be determined by examination of the genitalia. 

Cased Larva (or feeding signs) - please provide close-up photographs and state the host plant.

Roadside verges, waste places and disturbed ground where Mugwort is present.

Flight period is July and August.

The cased larvae feed on Mugwort.  They produce a case resembling the seed heads, and feed my moving from one seed head to the next, leaving a tell-tale hole in the seed head where feeding has taken place.

Coleophora artemisicolella has a scattered distribution extending from southern England to northern England and North Wales.

Rarely recorded in Leicestershire and Rutland. The Broughton Astley record of 11th July /2025 is the first for our area.