A migrant to the UK, it has been recorded less than four hundred times, most often at light from coastal counties of England but numbers are increasing, possibly supported by transitory breeding. Easily recognised by large metallic silver 'dog-leg' mark in the centre of a pinkish-brown bar on the forewing.
In mainland Europe, it is widely distributed and expanding its range westwards since the end of the 19th Century. Can be found on the continent from spring to late autumn in two broods, sometimes seen flying by day. Spends the winter as a young caterpillar.