Last modified: April 20, 2020, 11:06 a.m.
A rare species in Belgium, mainly in azalea nurseries and parks with Rhododendron.
A whitish, transparant cocoon.
The young larvae make a gallery in the lower epidermis of a leaf of Rhododendron simsii, R. indicum, etc. This gallery leads to a blotch contorting the leaf. Later, the larva constructs a cone by rolling a leaf downwards from the tip. Pupation on the underside of the leaf, where the larva first spins a whitish, transparant cocoon which is actually just a membrane. The pupa hibernates and after emergence of the adult the exuvium protrudes from the mine. The adults come to light.
The adults fly in two generations a year: in May and in July–August. In mild seasons there is a small third generation during September–October.