A brown, sometimes mottled, medium-sized (7.5 to 8.3 mm) water beetle which may be very similar to Agabus conspersus. Agabus nebulosus differs mainly in having two dark spots on the pronotum which are visible in the field. It is only safe to conclude whether pronotal spots are present by examination of a reasonably dry insect. 

Agabus conspersus has pale olive elytra with the central area mottled darker and a uniformly pale pronotum. As an additional check, the undersides of the front and middle femora in conspersus are usually marked with a black patch – this is absent in nebulosus.

Unless identified by a recognised expert, a photo is required and the specimen should be examined with a microscope. In the comments box, state the key or ID method used and describe the size and identifying characters.

Pools and small water bodies.

Recorded in most months of the year.

Widespread and fairly frequent in Britain.

Fairly frequent in Leicestershire and Rutland.