A video is circulating on Twitter with claims that the animal shown is 80 million years old – while this is obviously not true, let’s give them the benefit of the doubt as to how they reached this conclusion.
The video is from 2007 and was filmed at Awashima Marine Park In Japan. It’s racked up an impressive 8.7 million views since it was posted on October 14.
The species in the video is a frilled shark (Chlamydoselachus anguineus), an extremely rare deep-sea beastie that typically lives at depths between 120-1,280 meters (394-4,199 feet).
The shark's name refers to its row of six frilled gill slits. This species can grow to 2 meters (7 feet) long and has around 300 trident-shaped teeth over 25 rows. This species has a wide but patchy distribution, popping up in places such as the coast of Norway, Portugal, and even Victoria, Australia.
With a body like an eel and that fearsome mouth, it does look like an ancient creature from the deep. Often given the nickname of “living fossils”, researchers think that the species (not the individual shown in the viral video) is one of the most ancient surviving, having not changed much in the last 100 million years of evolutionary history.
The frilled shark is in its own family, the Chlamydoselachidae, believed to be the oldest living family of elasmobranches (sharks, skate, and rays).
Frilled sharks belong to the order Hexanchiformes that lived in the time of the Cretaceous. Fossils of this species have been found that date back 80 million years, which means they were swimming around in the sea at the same times as Triceratops were roaming around on land.
However, the lifespan of an individual is thought to be around 25 years, not 80 million. If you’re still desperate for an impressive shark lifespan fact, Greenland sharks are the world’s longest-living vertebrates, with some living around 500 years.