Wingspan 30 to 34 mm. Quite variable across its range, the northern populations often include a number of dark grey, melanic specimens.

Damper areas where Alder is present.

Flies from late April to July.

Alder (Alnus glutinosa) is the larval foodplant, the caterpillars spinning together the leaves during the autumn.

It is found throughout most of Britain. In a recent survey to determine the status of all macro moths in Britain this species was classified as common.

Fairly frequent but not common in Leicestershire and Rutland. L&R Moth Group status = B (scarce resident or restricted distribution or regular migrant).