fairly common species in Belgium.
yellowish larva makes a leafmine on Betula. Egg is usually laid on
the underside of the leaf, close to a vein. The
mine starts as a narrow not strongly contorted gallery, not
discolouring the leaf tissue and the brown or black coiled frass lying
in arches, leaving very narrow clear margins. Often the mine starts
near the leaf margin and after the usually early whirls progresses in a
straight line beside a rib. Pupation in a pale buff
cocoon among leaf litter.
adults fly probably in two generations a year or perhaps in a single protracted generation.
Brabant, Zemst, 26 September 2008.
mine on Betula
(Photo © Jorgen Ravoet)