Wingspan 13-16 mm.
Virtually identical to the closely related N. singula from which it is best separated by locating the larva (see below). The moth is restricted to a few sites in Kent and, recently, at a single site in Middlesex.
The larva of both species feed on sheeps sorrel (Rumex acetosella) in May and early June in a silk tube at the base of the stem. The larva of N. peliella is chocolate-brown and that of N. singula pale dull green - both have black heads.
Adults fly during July and come to light.