Endangered (proposed as a future Red Data Book species) in marshes, river-banks and damp areas in parts of East Anglia. Not recorded in Hampshire or on the Isle of Wight to date. Wingspan 12-14 mm. Similar to
A. badiana but distinguished by the lighter general coloration of the forewing, the narrower basal patch, the median fascia which has the outer edge lined throughout with white and the upper part more strongly concave, and in particular by the presence of three or sometimes four black dots at the base of the cilia below the subapical dash [Bradley]. Larva feeds on Marsh Pea, living between leaves spun together with silk, over-wintering in a cocoon.