Wingspan 17 to19 mm. This moth derives its English name from the reddish patches at the tips of the forewings.

The species inhabits fens, marshes and other damp localities.

It flies between May and July.

Larvae feed inside the stems of various species of Willow and especially Osier.

It can be found locally throughout much of England, southern Scotland, south Wales and scarcely in parts of Ireland. In a recent survey to determine the status of all macro moths in Britain this species was classified as Nationally Scarce B, but the introduction of an effective pheromone lure for this species has shown it to be more common than previously thought.

Previously thought uncommon in Leicestershire & Rutland, but the introduction of an effective pheromone lure for this species has shown it to be more common in our area than previously thought.