Argyresthia semitestacella is a moth of the family Yponomeutidae. It is found in Europe.
The wingspan is 11–14 mm. The head is yellowish white. Forewings are light ferruginous-brown, faintly purplish tinged; a thick whitish dorsal streak to tornus, interrupted by a dark ferruginous-brown triangular median spot. Hindwings are grey.[1]
In the United Kingdom, the moth flies from Aguust to September. The larvae feed on beech.