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Maybe pythons - some types of crocodile/alligators. But that's very region specific.

Sharks as well.

Sturgeon. Maybe lamprey (I've never tried it)

Molluscs? Snails have been around a very long time in one form or another.

Oysters and other bivalves too...

Catshark maybe, although I don't know if that species in particular is old enough.

Any. Title says "food".