The Pointed Campeloma snail has a large rounded shell. It lives on sand bars in shallow water.
The smaller sharp hornsnail has a thick, cone-shaped shell with one or two dark bands. This snail glides along the river bottom on its round, fleshy foot. It eats algae, including diatoms. Each of its two slender tentacles has an eye at its base. Its mouth is at the end of a long snout.
The sharp hornsnail occurs throughout the Mississippi and St. Lawrence River basins. Look for it on algae-covered stones in clean, shallow water.