the world > animals > invertebrates > phylum Arthropoda > class Insecta > order Coleoptera or beetles and weevils > [noun] > member of (beetle) > aquatic > that swims on it's back (2)
A predatory aquatic bug of the genus Notonecta (family Notonectidae), which swims on its back propelled by its long back legs; a backswimmer. Also…
A predatory aquatic bug of the family Notonectidae; a backswimmer. Cf. Notonecta, n.