Aquarius paludum (14 to 16 mm) and A. najas (13 to 17 mm) can be distinguished from all other skaters found in England by their larger size. A. paludum is characterised by long abdominal spines that are angled upward and reach the tip of the abdomen, and by a yellow line along the side of the pronotum. A. najas has shorter spines and no yellow line.

Aquarius najas

Good close up images required showing identification features. Detailed examination may be required.

Aquarius paludum inhabits the surfaces of a wide variety of freshwater habitats both temporary and permanent.

Most likely to be observed in summer and autumn.

Widespread in the southern half of Britain, it seems to be rather infrequent and most often recorded in the south east of England.

Rarely recorded in Leicestershire and Rutland.