Water boatmen are shaped like a flat football and average in length from 1/3”-1/2” maximum. Their oar shaped legs are distinguishing because of their oaring locomotion. Boatmen carry a bubble on their belly. Their body color is a drab brownish black with subtle barring of dirty yellow, brown olive, gray-brown. The belly is a light to dark brown or dirty white to dull yellow.
Snails have a rather unique shell with a retractable body. Their body colors usually match the colorization of the water bottom, with olives, browns, or blackish shells.
Notonectidae (backswimmers, water boatmen; order Hemiptera, suborder Heteroptera)
Family of predatory, aquatic bugs, which swim in the water with their backs directed downwards, propelling themselves by means of the hair-fringed hind pair of legs; hence their common names. The front two pairs of legs are used to grasp prey. There are about 200 species, distributed world-wide.
Aquatic insect found worldwide. Its body is grey to black, oval and flat, with fringed, oar-like hind legs. Length: about 15mm (0.6in). Order Hemiptera; family Corixidae. The carnivorous ‘backswimmers’ of the family Notonectidae are also sometimes called water boatmen.