notes

In many parts of the world, the adults of

Dytiscidae, particularly the large-bodied

genera Cybister and Dytiscus, form part

of the human diet. Although crunchy in

texture, they are high in protein and readily

available. However, there have been

concerns that because of their relatively

long life and predatory habits, they may

accumulate pollutants

Most great diving beetles are greenish, oily black

or brown, often with yellow margins and a patterned

underside. The male has suction pads on the fore

legs to hold the female during mating, and the

females of several genera have evolved ridges

on their backs to prevent unwanted attention.

right | Dytiscus marginalis Female (left)

and male (right) adults. The female

is recognizable from the ridged elytra,

the male by the suctorial pads found

on the fore legs.

above | Eretes australis An Australian

diving beetle with a large air bubble.

The hind legs are for swimming, the

others for anchoring on substrate.