im Emmet ist lediglich der Jugendsack von C. kuehnella abgebildet (dort unter dem Namen C. palliatella). Im Text heißt es dazu: Raupenschlupf Ende September, keine Anfangsmine. "A black silken case, c. 5.0 mm long, is constructed and later coated with frass. The dorsal surface is arched and the ventral surface straight except for a slight projecting keel in the centre; the oral opening is at 0° to the long axis. The larva mines the leaf from the underside, the feeding pattern being distinctive. Holes no bigger than the oral opening are chewed out, leaving the upper epidermis intact; there is no lateral extension as in the mines of most coleophorids. The mines are arranged in contiguous groups numbering from two or three to c. 30. The larva avoids even the smallest veinlet... The anterior end of the case is soon extended and wing-like flaps are constructed which extend laterally from a point near the oral opening. These 'wings' are corrugated and slightly concave and are composed of a mixture of grey and whitish silk. The original part of the case extends backwards like a tail and at this stage the case resembles a miniature skate or ray." (skate, ray = Rochen) "The larva continues to feed often into November before attaching its case to an angle of a twig for the winter."
Zu C. currucipennella schreibt er: "The larval habits in the autumn seem to have been almost unobserved. Probably a silken case is constructed before feeding begins; the larva then mines leaves in the normal manner. After the winter it ceases to mine and eats out windows or complete holes in the leaves."
Zu C. ibipennella: Raupenschlupf Mitte September, danach Minierstadium. "During this period it forms its case from silk mixed with frass; it is c. 1.5 mm long, black and roughened by the frass particles; dorsal surface slightly arched; ventral surface weakly keeled; oral opening at 0° to the long axis. Once the case has been formed, the larva ceases to mine and grazes on the lower surface of the leaf, leaving the upper epidermis intact and even the smallest veinlets uneaten. The feeding patches, which are contiguous, resemble a series of tiny mines but if the larva is watched whilst feeding it is clear that it is grazing externally." Jetzt wird's interessant: "C. lutipennella Zeller and C. flavipennella (Duponchel) feed wholly by mining and their mines are less closely grouped; consequently the feeding of the pistol-case species can easily be recognized from the upper surface of the leaf before the case itself has been seen. As the case is enlarged, more frass is incorporated, but the shape is altered little in the autumn. Feeding continues until late October, when the larva enters diapause with its case fixed at an angle of a twig or at the base of a bud."
Zeig doch mal die Säcke. Haben sie bereits "Flügelchen", so sollte es C. kuehnella sein.