Apple snails are tropical and sub-tropical freshwater snails from the family Ampullariidae. The Ampullariidae are divided in several genera. The genera Asolene, Felipponea, Marisa, and Pomacea are the New World genera (South America, Central America, the West Indies and the Southern U.S.A.). The genera Afropomus, Lanistes and Saulea are found in Africa. The genus Pila is native in both Africa and Asia.
Apple snails are exceptionally well adapted to tropical regions with periods of drought alternated with periods of excessive rainfall. This adaptation is reflected in their life style: moderately amphibious and being equipped with a shell door enabling the snail to close its shell (to prevent drying out while hiding in the mud during dry periods).
A typical adaptation of apple snails is the combination of a branchial respiration system comparable with the gills of a fish (at the right side of the snail body) and a lung (at the left side of the body). This lung/gill combination expands the action radius of the snail in search for food.
Many apple snail species deposit the eggs above the waterline in a calcareous clutch. This remarkably strategy of these aquatic snails protect their eggs against predation by fish and other water inhabitants. Another predator specific adaptation in the apple snail genera Pomacea and Pila, is the tubular siphon at their left side, used to breathe air while they stay submerged, thus making them less vulnerable to snail eating birds.
Apple snails inhabit various ecosystems: ponds, swamps and rivers. Although they occasionally leave the water, they remain mainly submerged.
In spite the fact that many snail species are hermaphrodite (being male and female at the same time) apple snails are definitely not: they have separated sexes (gonochoristic) and a male and a female are needed for reproduction.
Pomacea diffusa (spike-topped apple snail, Brazilian apple snail, golden mystery snail and ivory snail) prefers dead and rotting plants above fresh green ones. Occasionally they eat the softer vegetation. Pomacea diffusa snails are thus a good choice for an aquarium equipped with a nice collection of water-plants. What is even more: they tend to starve to dead in the middle of the vegetation if you don’t provide them with enough food. The Pomacea diffusa apple snails do very well on all kind of fish food and soft vegetables.
Although floating food might seems a bit strange for snails, apple snails know very well how to handle it. They go to the surface and form a funnel with their foot in which they let the water from the surface flow through. The food at the surface then floats towards the snail and gets stuck in this funnel after which the snail eats the catch.