Bud-borer and case-bearer: The larva bores into expanding leaf buds, and later skeletonizes young leaves, rarely mining a leaf in the usual manner of other Coleophora species. It builds a 'pistol case' from silk and fragments of leaf and frass. The sides of the case are usually adorned with hairs from the leaf surface, this feature serving to distinguish it from the similar case of C. anatipennella, which feeds on sloe (Prunus spinosa) and other rosaceous trees and shrubs (UKMoths).

Blackish brown pistol case of about 7 mm, with a mouth angle of c. 70° standing almost erect on the leaf. The case is decorated with white wool, originating from the hostplant. In comparison with C. zelleriella the case is more paunchy (Bladmineerders van Europa).

The case is also illustrated in British leafminers and the Encyclopedia of Life.

Larva: Details unknown.

Pupa: Details unknown.

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

Hosts in Britain:

Hosts elsewhere:

Time of year - larvae: Autumn-May (British leafminers). Larvae are full grown about end May (Emmet et al., 1996a).

Time of year - adults: June and July, and often comes to mercury vapour light (UKMoths).

Distribution in Great Britain and Ireland: Widely distributed in the southern half of the British Isles in wet or marshy areas, damp woodland and fixed dunes (UKMoths) including Anglesey, Cambridgeshire, Denbighshire, East Cornwall, East Kent, East Suffolk, Flintshire, Glamorgan, North Essex, North Somerset, Pembrokeshire, South Hampshire, South Lancaster, South Wiltshire, West Cornwall, West Gloucestershire, West Suffolk and Westmorland (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) and Ireland (Karsholt and van Nieukerken in Fauna Europaea).

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 Austria, Belgium, Crete, Czech Republic, Danish mainland, Estonia, Finland, French mainland, Germany, Hungary, Italian mainland, Latvia, Liechtenstein, Lithuania, Luxembourg, Norwegian mainland, Poland, Portuguese mainland, Romania, Russia - East and South, Sicily, Slovakia, Slovenia, ? Spanish mainland, Sweden, Switzerland and The Netherlands (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.