The term ramshorn snail or ram's horn snail is used in two different ways. In the aquarium trade it is used to describe various kinds of freshwater snails whose shells are planispiral, meaning that the shell is a flat coil. Such shells resemble a coil of rope, or a ram's horn. In a more general natural history context, the term "ramshorn snails" is used more precisely to mean those aquatic pulmonate gastropod mollusks in the family Planorbidae that have planispiral coiled shells.
Marisa cornuarietis, common name the Colombian ramshorn apple snail, is a species of large freshwater snail with an operculum, an aquatic gastropod mollusc in the family Ampullariidae, the apple snail family.
Planorbidae, common name the ramshorn snails or ram's horn snails, is a family of air-breathing freshwater snails, aquatic pulmonate gastropod molluscs. Unlike most molluscs, the blood of ram's horn snails contains iron-based hemoglobin instead of copper-based hemocyanin. As a result, planorbids are able to breathe oxygen more efficiently than other molluscs. The presence of hemoglobin gives the body a reddish colour. This is especially apparent in albino animals.
Planorbarius corneus, common name the great ramshorn, is a relatively large species of air-breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails, or planorbids, which all have sinistral or left-coiling shells.
Gyraulus crista, commonly called the Nautilus ramshorn, is a minute species of freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails.
Anisus vorticulus is a species of minute, air-breathing, freshwater snail, an aquatic gastropod mollusk in the family Planorbidae, the ramshorn snails.
Planorbella is a genus of freshwater air-breathing snails, aquatic pulmonate gastropod mollusks in the family Planorbidae, the ram's horn snails, or planorbids, which all have sinistral, or left-coiling, shells.
Anisus spirorbis is a species of small freshwater air-breathing snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails.
Anisus leucostoma is a European species of small air-breathing freshwater snail, an aquatic pulmonate gastropod in the family Planorbidae, the ram's horn snails and their allies.
Planorbella multivolvis, the acorn ramshorn, was a species of small freshwater air-breathing snail, a pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails.
Planorbis carinatus is species of air-breathing freshwater snail, a pulmonate gastropod mollusk in the family Planorbidae, the ramshorn snails.
Physa fontinalis, common name the common bladder snail, is a species of air-breathing freshwater snail, an aquatic gastropod mollusc in the family Physidae. The shells of species in the genus Physa are left-handed or sinistral.
Bathyomphalus contortus is a species of small air-breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails and their allies.
Gyraulus albus, common name white ramshorn, is a small species of freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails.
Helisoma anceps, common name the two-ridge rams-horn, is a species of air-breathing freshwater snail, a pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails.
Menetus is a North American genus of freshwater snails, aquatic pulmonate gastropod mollusks in the family Planorbidae, the ramshorn snails.
Freshwater snails are gastropod mollusks that live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs to major rivers. The great majority of freshwater gastropods have a shell, with very few exceptions. Some groups of snails that live in freshwater respire using gills, whereas other groups need to reach the surface to breathe air. In addition, some are amphibious and have both gills and a lung. Most feed on algae, but many are detritivores and some are filter feeders.
