The ground colour is light brown or white brown to reddish brown
The forewings, which exhibit a fine regular pattern of dark, finely serrated lines have a dark eye patch in the middle. Under the sickle, or on the outer part of the outer edge of the wing, there is a purple stain. From the wing tip, a clearly curved, dark brown band runs under the stain up to the edge of the wing.
The hindwings are also light brown in colour, but brighter than the forewings. Their pattern is similar to but not so strong as that of the forewings. In the females the hindwings are white with the same dark patterning.
Srpokřídlec vrbový
Birkeseglvinge
Heller Sichelfluegler
Kase-sirptiib
Pebble Hook-tip
Faucille 
Bērzu sirpjspārnis
Juodataškis lenktasparnis
Nyárfa-sarlósszövő
Berkeneenstaart
Bjørkesigdvinge
Wycinka sierpianka
Srpokrídlovec jelšový
Täpläsirppisiipi
Ockragul sikelvinge
Серпокрылка березовая