Common Backswimmer - Notonecta glauca


Up to nearly 2 cm in size, and commonly called backswimmers because they swim upside down and are often seen at the surface of the water. Notonecta glauca is light brown in colour with a number of dark markings and large reddish eyes. It often looks silvery as air becomes trapped in a layer of bristles covering the lower surface. The powerful oar-like hind legs are modified for swimming; they are long, flattened and fringed with hairs


Water dwelling, in ponds, cattle troughs, etc.

When to see it

All year round.

Life History

Backswimmers are predators that attack prey as large as tadpoles and small fish, the forelegs, which are short and strong, are used for grabbing prey. In contrast to other aquatic insects that cling to submerged objects using the extra oxygen supply from haemoglobin in their abdomen, instead of using oxygen dissolved in the water.

UK Status

Common: the most widespread and abundant of the genus in Britain.

VC55 Status

Very common in Leicestershire and Rutland.

Leicestershire & Rutland Map

UK Map