Nanaimoteuthis haggarti re-estimated at 7-19m in new study
Updated
Updated · BBC Discover Wildlife · May 2
Nanaimoteuthis haggarti re-estimated at 7-19m in new study
3 articles · Updated · BBC Discover Wildlife · May 2
The Science paper says the Late Cretaceous octopus, known from 84-million-year-old fossils from Vancouver Island and Hokkaido, may have rivalled or exceeded the colossal squid and Mosasaurus hoffmani.
Researchers revised the animal from a supposed vampire squid to a cirrate octopus after re-examining more than a dozen jaws and an exceptionally well-preserved specimen, using jaw-to-body scaling from living octopuses.
They infer it lived in deep North Pacific shelf seas and ate hard-shelled prey such as ammonites, though some scientists dispute the size estimates because cephalopod body dimensions are difficult to infer from jaws alone.
A fossil jaw suggests a 19-meter octopus existed. What evidence could finally prove this prehistoric 'Kraken' was real?
This giant octopus may have topped the food chain. Could it truly have preyed upon the mighty 17-meter Mosasaurus?
AI helped reveal this colossal octopus. What other 'invisible' ecosystems is this technology now uncovering from Earth's deep past?
In 2025-2026, researchers used AI-assisted fossil mining and 3D modeling to re-estimate the size of the prehistoric octopus Nanaimoteuthis haggarti, revealing it could reach up to 18.6 meters long. This challenged the belief that large marine reptiles were the only apex predators in the Cretaceous seas. Evidence from asymmetric beak wear and fin structures showed N. haggarti had complex hunting behaviors and was an active predator, competing with marine reptiles for prey like ammonites and fish. The species went extinct around 72 million years ago, possibly due to prey decline or ocean changes, and ongoing research continues to explore its ecology and extinction.