Stenoma cyanarcha is a moth in the family Depressariidae. It was described by Edward Meyrick in 1915. It is found in Guyana.[1]
The wingspan is about 10 mm. The forewings are dark fuscous, the basal half suffused with pale metallic green bluish and with a somewhat irregular almost straight white line from beyond the middle of the costa to two-thirds of the dorsum, rather dilated on the costa. The hindwings are dark fuscous.[2]