Last modified: April 10, 2021, 11:21 a.m.
A rare species in Belgium, recorded from many localities but always in low numbers.
Forewing brownish grey with a row of inconspicuous, small whitish striae along the costa; some brownish spots in the middle of the wing and near the inner margin. Identification of the adults is difficult without knowledge of the larval host plant, because the resemblance with other Parornix species, and genitalia should be studied.
Yellowish to yellowish green, light brown head capsule. Legs yellowish green to pale brown (in Parornix finitimella the legs are black). First prothoracic segment with two dark brown to blackish spots (in Parornix finitimella four such spots), but this character cannot be used as an identification character as it is variable.
The first instar makes a short, narrow gallery on the underside of the leaf, soon widening into a blotch and later on, by applying some spinning, into a weakly inflated tentiform blotch with a quadrangular shape when it is situated between two veins, or triangular when it is situated in a vein axil. The dark frass is concentrated in a corner of the mine. The mine becomes transparant when almost all the tissue is consumed.
See also gracillariidae.net and bladmineerders.be.
The free living instars fold a leaf margin downwards and continue feeding on the leaf parenchyma within this fold. On small leaves, this fold can occupy the entire leaf.
Pupation in the fold, and hibernation between leaf litter on the ground.
The adults rest during the day in the oliage and they become active at dusk and during the night. They come to light.
The adults fly in one generation from May till mid July.