With 35,000 different gastropod species classified, there's a lot of variety in snail habitats and diets. Snails, which are all gastropods, have adapted to life on land, fresh water and salt water. Most snails are omnivores, while others are herbivores or even carnivores.
Terrestrial snails live in in Africa, Asia, Australia, Europe, North America and South America. They can live in a wide range of temperatures, from cool mountain tops to steamy jungles. Land snails may live on the ground or in trees, or move between both. The common garden snail (Helix aspersa) is widespread in Europe. It's a small snail with a shell only about 1 inch long that spends its days munching on plant leaves and hiding under rocks, logs or overhanging leaves to avoid predators. The giant African land snail has become notorious in many countries for its prolific breeding and huge appetite. It has been named one of the most invasive species in the world. GALS' shells can grow up to six inches long and their bodies can stretch to 10 inches. They're native to African rainforests, but easily adapt to just about any habitat where winters aren't extremely harsh. They primarily eat fruits, vegetables and leaves and live terrestrially as well as arboreally.
Aquatic snail species are abundant on almost every continent. Ponds, streams, lakes and rivers are often populated with snails. Freshwater snails may subsist on a variety of diets, such as decaying matter or algae. Certain species of freshwater snails are commonly kept as aquarium pets, such as the mystery and apple snails (family Ampullariidae). In the wild they live in subtropical waters of South America. Tylomelania snails are striking freshwater snails, with long, black, spiraled, textured shells and bright yellowish-orange bodies. They originate from high altitude lakes in Sulawesi, near Borneo.
The largest, most colorful and intricately-shaped snails live in the world's oceans, which are home to 18,000 marine snail species. Saltwater snails live in a variety of habitats, from warm tropical reefs to inky black ocean depths. Conch shells that supposedly hold the sound of the ocean are actually home to very large tropical snails. The recently discovered armor-plated snail (Crysomallon squamiferum) is especially adapted to life near hydrothermal vents, thousands of feet below the ocean's surface. The world's largest marine snail is the Australian trumpet, Syrinx aruanus. Its shell can range in size from 4 to 27 inches long.
Most snails are omnivorous, meaning they eat just about anything that doesn't move. Often scavengers, omnivorous snails will eat living plants, dead plants and dead animal matter. Detritivorous marine snails may be benthic grazers, filter feeders or suspension feeders. Some snails are herbivores, eating almost exclusively plants. Humans consider them pests because they love to eat crops. A few snail species are even parasitic, such as the marine snail Melanella araeosomae.
Snails can be aggressive hunters, like the marine geographic cone snail (Conus geographus). It's considered one of the most venomous animals in the world and can even kill a human with its sting. Cone snails deliver their venom via a long tooth propelled by a proboscis they use to stun fish, their primary prey. The large, terrestrial Powelliphanta snails of New Zealand eat earthworms that they suck into their mouths like spaghetti. They may even eat slugs -- their fellow terrestrial gastropod brethren. The rosy wolfsnail (Euglandina rosea), a small arboreal snail native to Florida, is specially adapted to eat other snails.
- New Zealand Department of Conservation: Facts About Powelliphanta Snails
- The Living World of Molluscs: The Rosy Wolf Snail (Euglandina rosea)
- National Geographic: Geographic Cone Snail
- The Wonders of the Seas: Snails and Their Relatives
- The Apple Snail Website: The Ecology of Apple Snails
- Practical Fishkeeping: Snails from Sulawesi
- ARKive: Giant African Snail (Achatina fulica)
- ARKive: Garden Snail (Helix aspersa)
- Sea World: Marine Snails
- National Geographic: Armor-Plated Snail Discovered in Deep Sea
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