Blue-ringed octopuses carry a killer concoction called tetrodotoxin (TTX), a potent neurotoxin that can paralyze living things, including humans. Tetrodotoxin is most famously known from pufferfish — ...

But for Octopus briareus and many other octopus species, the story has a nasty ending. After a mother octopus lays a clutch ...

Unlike other octopus species, dumbo octopuses don't have ink sacks, presumably because they don't encounter as many predators at such great depths. 5. of 11. Blue-Ringed Octopus .

A Casper octopus photographed deep underwater. Discovered in 2016, this is the first time this rare octopus species—yet to receive its scientific name—has been seen in the Southern Pacific.

For the roughly 300 known octopus species dwelling in the world's oceans, having eight arms is a defining characteristic. But that is not the way it started.

They also found that, for octopus species that live in reef systems, their entire visual system undergoes major changes to accommodate their daytime-dwelling lifestyle.

The fourth species is an oddball. “It was just so unlike anything I had seen; I didn’t know where to assign it,” Voight says. But she and Vásquez observed a single row of suckers on each of ...

A new species of octopus may have just been discovered off the coast of Costa Rica. It was found in a rare brooding site that marks only the third octopus nursery known to exist in the world.

The octopus already is an oddball of the ocean. Now biologists have rediscovered a species of that eight-arm sea creature that’s even stranger and shares some of our social and mating habits ...

WASHINGTON (AP) – The octopus already is an oddball of the ocean. Now biologists have rediscovered a species of that eight-arm sea creature that's even stranger and shares some of our social and ...

A new study found that some members of an octopus species hunt cooperatively in groups with fish. Video shows octopuses punching their companion fish to keep them on task and contributing to the hunt.

Scientists have discovered at least four new species of octopus in the deep waters of a 100-square-mile area near Costa Rica, officials from the Schmidt Ocean Institute said on Tuesday.