ram's horn snail planorbella trivolvis freshwater air-breathing snail

tiny underwater community biology breathing wildlife lush aquatic delicate life horn miniature hanging air species wild crustacean freshwater little shell conch mollusk clean small snail healthy animal pond green mussel water snails nature slug environment escargot gastropod plant airbreathing leftcoiling planorbella planorbidae planorbids pulmonate rams ramshorn sinistral trivolvis