Snails don't make the easiest mouthful, but two groups of snakes (from Asia and South America) are particularly adept at consuming these slippery molluscs, says Laurie Jackson.
The snakes' jaws aren't powerful enough to crush rigid shells, but they have a secret weapon: more teeth on the right side than the left.
This lopsided dentition, combined with the unusual ability to move the sides of their jaws independently, enables them to firmly grip the shell Many snails have a hard operculum (used to block the shell entrance) that is potentially damaging if swallowed.
- Elephants have 'conveyor belt’ teeth, dolphins grow theirs in layers like trees, while sharks have a never-ending supply - so why are we stuck with just 2 sets?
- Deadliest teeth and most murderous mouths on the planet: Lethal weapons that kill by slicing, sucking, crushing, slashing or delivering deadly venom
The blunt headed snail-eating snake has a novel way of dealing with this. It repositions the freshly extracted snail to one side of its jaw, and uses the other to saw off the appendage in as little as six strokes.
The snake does have one nemesis, though: left-spiralling (sinistral) shells are unsuited to their bite and make for a challenging meal.
