Wing length 10-13 mm. The peppered wing pattern is variable  and can be quite pale. The top of the femora are yellow fading into the darker basal half. The top of the thorax has a  broad central dark stripe, plus side stripes. The abdomen is grey with a dark bar on each segment.

Limnophila pictipennis has a similar wing pattern but the yellow on the femora stops abruptly with a black basal band.

Streams, woods and well vegetated damp places.

April and May.

The larvae live in marshy places.

Widespread but rather local in Britain.

Local and rather infrequent in Leicestershire and Rutland.