(order Hemiptera, suborder Heteroptera)
Family of aquatic bugs which swim by means of the hair-fringed hind pair of legs, with their backs uppermost. They filter edible animal and vegetable matter from the debris at the bottom of ponds with their scoop-shaped and bristle-fringed front pair of legs. There are more than 200 species distributed world-wide.
Subjects: Zoology and Animal Sciences.