The wingspan is 10–13 millimetres (0.39–0.51 in). Forewings purplish - ferruginous ; dorsum suffused with yellow towards base ; a large triangular yellow median costal blotch, apex often rounded. Hindwings dark grey. .[3]
The moth flies from May to July depending on the location.
^Meyrick, E., 1895 A Handbook of British Lepidoptera MacMillan, London pdf This article incorporates text from this source, which is in the public domain. Keys and description