Wingspan 12-13 mm.
A rather local species which is slowly increasing its range. It occurs in scattered colonies in central and southern England, but also occasionally elsewhere.
Like other members of its genus, the larva creates a succession of cases, in this instance fashioned from parts of a leaf of the foodplant, alder (Alnus). The species overwinters in one of these cases, in some populations twice before emerging as an adult.
The moths are golden-brown in general colouration, with a cream or whitish leading edge to the forewing, and occur mainly in July and August. As mentioned, some populations only produce adults every two years.