Scientists studying Greenland sharks pulled from the Arctic ocean have estimated one individual's age at 392 (plus or minus 120 years), another's at 335 (plus or minus 75 years) and 27 others averaging 272 year old. For reference, that's older than shit. I even know some undead warlocks who are younger, but even uglier.
Young or old, Greenland sharks (Somniosus microcephalus, literally "tiny-headed sleeper") are extraordinary creatures. They're the second-largest carnivorous sharks in the world, reaching 2500 pounds [and up to 24-feet]. Their teeth are shaped and angled to remove plugs of flesh from their prey, and their own flesh is poisonous.
Even so, Greenland sharks, like most sharks, present no risk to humans. They're incredibly slow swimmers and live deep, deep down in the icy waters of the Arctic Ocean.
If confirmed, this would make Greenland sharks the oldest known species of vertebrate. My enemies? My enemies aren't in the running because 1) they're all spineless and 2) I would never let them live long enough to to be the oldest known anything. Still, no word what kind of underhanded deal these sharks made with Ursula to live so long.
Thanks to Marcus O, who's convinced Greenland sharks clearly found the Holy Grail and each sips from it when they reach maturity.