Cosmopterix orichalcea

Cosmopterix orichalcea is a moth of the family Cosmopterigidae. It is known from most of Europe (except the Balkan Peninsula) east to Japan.

The wingspan is about 9 mm. The antennae with apex and two subapical rings white. Forewings black; a large brassy-metallic basal patch, edge very oblique; a broad orange fascia beyond middle, narrowed dorsally, edged with black scales and then with narrow violet-golden-metallic fasciae; a bluish-silvery-metallic sometimes interrupted streak along upper. The larva is pale yellow; dorsal line greenish; head black plate of 2 black, bisected.

Adults are on wing from August to May. Then the larva hibernates outside of the mine in a hibernaculum.

The larvae feed on Anthoxanthum odoratum, Festuca arundinacea, Hierochloe odorata, Milium species, Phalaris arundinacea and Phragmites australis. They mine the leaves of their host plant.