Ectoedemia argyropeza

Wingspan about 7 mm. It lacks discrete white spots but does show a suggestion of mid-costal and dorsal white spots; frontal tuft pale ferruginous, collar concolorous; eyecaps white. The larva mines the leaves of Aspen, first galling the leaf petiole, then forming a triangular blotch extending from the midrib.  The larvae continue to feed in 'green islands' in fallen leaves. 

Adult Leafmine

Where Aspen is present.

There is a single generation, and the adults are on the wing in May and June.

The larva mines the leaves of Aspen (Populus tremula). Parthenogenetic (females only).

Locally distributed throughout mainland Britain, though more plentiful in the south. In the Butterfly Conservation's Microlepidoptera Report 2011 this species was classified as local.

Increasingly well recorded in Leicestershire and Rutland in recent years, particularly from the leafmines on Aspen

http://www.leafmines.co.uk/html/Lepidoptera/E.argyropeza3.htm

https://bladmineerders.nl/parasites/animalia/arthropoda/insecta/lepidoptera/monotrysia/nepticuloidea/nepticulidae/ectoedemia/ectoedemia-argyropeza/