Coleophora serratella (Linnaeus, 1761)
Betula pubescens, Belgium, prov. Luxembourg, Bovigny, Chifontaine: mine; © Jean-Yves Baugnée
very young youth case
Crataegus, Ankeveen: old youth case, after hibernation
Ulmus, Duin- en Kruidberg: case of full grown larva
Betula pubescens, Belgium, prov. Luxembourg, Bovigny, Chifontaine: case of full grown larva; © Jean-Yves Baugnée
Betula pubescens, Heerde, lg de Dellen © Hans Jonkman. The case is so young that the teeth, originating from the leaf margin, still are green.
same case, dorsal view
The egg is deposited at the underside of the leaf, usually in a vein axil in the basal half of the leaf. The larva emerges through the micropyle (on top), and first crawls some distance over the leaf, before penetrating. The strongly curved youth case is is a “composite leaf case”, the adult case is a “tubular leaf case”. The adult case s trivalved, about 7 mm in length; the mouth angle is around 30°. The case is straw coloured and almost always has a toothed dorsal keel (remnant of the margin of the leaf from which the case was cut).
Rather polyphagous on woody plants
Alnus glutinosa, incana, viridis; Amelanchier ovalis; Betula nana, pendula, pubescens; Carpinus betulus; Chaenomeles; Corylus avellana; Cotoneaster; Crataegus monogyna; Cydonia; Eriobotrya japonica; Forsythia; Hippophae; Malus domestica, sylvestris; Mespilus germanica Myrica gale; Ostrya; Populus; Prunus Ribes; Salix caprea; Sorbus aucuparia; Spiraea bumalda, x vanhouttei; Ulmus glabra.
Despite all polyphagy, the species is, at least in the Netherlands, by far most common on Alder and Birch. References to Rosaceae often actually refer to coracipennella (see below).
The larvae easily stray to other plants; this explains the reference by Buhr (1936a) of serratela as an occasional miner on Ribes; also the reference by Szőcs (1977a) to Geranium must thus be explained.
Larvae start feeding in September and continue to the end of October. They hibernate in their case, and resume feeding in April. After some weeks they exchange their youth case for the definite one, and continue till early June (Emmet ao, 1996a).
This time table is not without exceptions: the picture above of the young youth case by Jean-Yves Baugnée was on April 24th, 2011.
BE recorded (Phegea, 2009).
NE recorded (Kuchlein & de Vos, 1999a; Microlepidoptera.nl, 2009); very common.
LUX recorded (Fauna Europaea, 2009).