Last modified: Jan. 5, 2020, 5:13 p.m.
This is a very rare species that is easily confused with some other Coleophora species (see remark in 'Bionomics').
This species is uniformly dark grey. Its wingspan is 8–12 mm. The antennae are alternately ringed ochreous brown till the tip.
At first, the tubular and tri-valved leaf case is light brown but when it reaches its final length of 6–7 mm it has darkened considerably. The mouth angle is circa 45°.
See also bladmineerders.be.
Initially, the larvae live at the underside of the leaves making small blotch mines which are excised to construct a case. After hibernation inside the case, the caterpillars resume feeding, construct a new case and cause sizeable fleck mines. They reach maturity by the end of May and pupate in June within the case which is attached to the upper side of a leaf.
Dissection of the genitalia is required to identity this moth with certainty since nor the external morphology, nor the larva or case allow to distinguish it from some other Coleophora species (C. prunifoliae, C. serratella and C. spinella). The hostplant can give a hint into the right direction but, Coleophora larvae being rather active when searching for a suitable pupation spot, this can lead to erroneous conclusions.
For this reason, often the name Coleophora nigricella (Stephens, 1834) –that is in fact a junior synonym of C. coracipennella– is used as a collective name for the four species mentioned.
The adults are on the wing from the end of June till the beginning of August.
The caterpillar is polyphagous on Rosaceae but is found mostly on Prunus spinosa and Malus spp. Also species of Cotoneaster, Crataegus, Prunus and Sorbus are accepted as hostplant.