I've never seen a snail quite like that before. The nearest I can think of is an apple snail, Pomacea diffusa.
Some of the photos are missing from this thread but if you compare your snail to the photos which are still there, you might be able to ID it.
Basic Terminology for Identification Anatomy: Foot: the bottom, muscular portion of the animal used for locomotion. Siphon: a proboscis-like appendage appearing on the side of the shell in some species. Mantle: the soft tissue inside the opening of the shell. Spire: the conical part of a...
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