Endangered (proposed as a future Red Data Book species) and confined to unimproved grassland in the Breckland area of East Anglia, a species of conservation concern under the UK Biodiversity Action Plan. Not recorded in Hampshire or on the Isle of Wight to date. Wingspan 16-19 mm. Similar to C. lixella, but with upperside of apical portion of antenna ringed fuscous (MBGBI Vol 3). Larva mines leaves of Basil Thyme and various grasses, living within a movable case; case length 9 mm.