About Achlya flavicornis Linnaeus, 1758
Achlya flavicornis, commonly known as the yellow horned, is a moth species belonging to the family Drepanidae. Carl Linnaeus first described this species in the 10th edition of Systema Naturae, published in 1758. Its distribution ranges from Europe across to the eastern Palearctic ecozone. This moth has a wingspan of 35–40 mm, with forewings measuring 17–20 mm in length. The base wing color is greenish grey, and some individuals are speckled or dusted with darker grey. The reniform and orbicular wing markings are typically clear and distinct; in some specimens, these marks fuse into a single whitish blotch outlined with blackish color. The cross lines on the wings are usually well defined, but they become very obscure in darker grey dusted individuals. This moth flies from February to April, with the exact flight period varying by location. Full-grown final instar larvae have two common color forms: some are entirely off-white, while others are off-white below the spiracles and darker greyish or olive green on the dorsal side. Larvae have a row of black spots paired with fine white black-edged dots. The species overwinters as a pupa inside a cocoon, located among leaf litter. Larvae feed on birch.
