Scientists recently discovered the fossilized jawbone of Nanaimoteutit hagarti, a giant kraken-like octopus that roamed the Earth some 72 million years ago. These giant cephalopods were some of the largest marine creatures of the Cretaceous period, and may have been the largest invertebrates in history, according to a recent study published in the journal Science.
“These findings revise the view of the Cretaceous ocean as a world dominated only by large predators,” study co-author Yasuhiro Iba, a paleontologist at Hokkaido University in Japan, told Live Science. “They show that the octopus, a large invertebrate, also occupied the top of the food web.”
Where the fossilized remains of a kraken-like octopus were discovered
Researchers working in Japan’s Ezo Group, a large Late Cretaceous formation on Hokkaido Island, and the Nanaimo Group on Canada’s Vancouver Island have discovered an extremely large jaw fossil. The jaws appear to belong to an octopus-like creature, but its exact classification, size and possible ecological role remain a mystery, according to Science News.
The researchers identified 12 more jaw fossils in Japanese rocks and examined 15 previously discovered jaw fossils. According to the Natural History Museum, the creatures were classified into two species, N. Jeletzkyi and N. Haggarti, based on their size and shape.
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How big was the Kraken-sized octopus?
The top marine predators were all thought to be vertebrates such as plesiosaurs and mosasaurs.
The study calculated that N. zeretskii’s body length can reach 10 to 26 feet, based on its largest jaw, and the newly discovered N. hagarti’s body length is 23 to 62 feet. According to the Creation Research Institute, this suggests N. haggarti may be the largest invertebrate ever discovered.
The discovery may show that prehistoric marine ecosystems were much more complex than previously imagined, with a wide variety of predators.

