Leaf-miner and case-bearer: This species produces a distinctive larval case in its later stages with a noticeably serrated upper edge, and affixed almost parallel to the leaf surface. The larvae overwinter when small and recommence feeding in late spring (UKMoths).

Oviposition generally in a vein axil. From there a short, relatively wide corridor is made that quickly widens into an elliptical blotch. Much of the frass is ejected through the hole that the larva has made to bore itself into the leaf (in C. badiipennella, on the same host plant, the frass remains within the mine. This blotch is excised to make the juvenile case. The full grown larva lives in a brown spatulate leaf case of 9-11.5 mm; its rear end is bivalved. Mouth angle 0°-20°; just behind the mouth the case shows a conspicuous bend (Bladmineerders van Europa).

Feeding traces and the case are illustrated in the Encyclopedia of Life.

Larva: The larva is illustrated in Bladmineerders van Europa.

Pupa: Details unknown.

Adult: The adult is illustrated in UKMoths. The male and ? female genitalia are illustrated by the Lepidoptera Dissection Group.

Hosts in Britain:

Hosts elsewhere:

Time of year - larvae: September to October, feeding again in June and July (British leafminers).

Time of year - adults: The elusive adults emerge in June and July (UKMoths).

Distribution in Great Britain and Ireland: Distributed mainly in the south and south-east of England (UKMoths) including Bedfordshire, Cambridgeshire, East Kent, East Norfolk, East Suffolk, Herefordshire, Hertfordshire, North Ebudes, North Essex, North Hampshire, North Somerset, North Wiltshire, Radnorshire, Shropshire, South Essex, South Hampshire, South Wiltshire, Stafford, Surrey, Warwickshire, West Gloucestershire, West Kent, West Suffolk and Worcestershire (NBN Gateway - N.B. includes Watsonian Vice Counties having publicly available records that fall within or overlap the vice county border at 10km resolution or better i.e. a record for a vice county may relate to an adjacent vice county - for included datasets see NBN Grid map below).

NBN Grid map: Note that not all datasets on the NBN Gateway may be available on the map below. If you are an NBN Gateway registered user you can request access for missing datasets via the link 'Open interactive map in new window' below.

Distribution elsewhere: Widespread in continental Europe including Albania, Austria, Belgium, Croatia, Czech Republic, Danish mainland, Estonia, Finland, French mainland, Germany, Greek mainland, Hungary, Latvia, Lithuania, Macedonia, Norwegian mainland, Poland, Romania, Sardinia, Sicily, Slovakia, Sweden, Switzerland, The Netherlands. Also recorded in Near East (Karsholt and van Nieukerken in Fauna Europaea).

NBN interactive distribution map(s) of known host species in Great Britain and Ireland and elsewhere:

Parasitoids in Britain and elsewhere: Unknown.