Enigmatic octopuses that have been newly discovered in the waters off Costa Rica add to a growing registry of deep-sea dwellers.

True crabs evolved to migrate between marine and land environments multiple times throughout their 250 million-year-old history, new study finds.

A large population of snow crabs in the eastern Bering Sea collapsed after a marine heat wave in 2018 and 2019 that multiplied the crabs' caloric needs and drove them to starvation.

Irukandji jellyfish, which are around the same size as a dime, have a venom-filled sting that can trigger an extremely painful and occasionally deadly syndrome.

French photographer Laurent Ballesta has received this year's Wildlife Photographer of the Year award for his image of a tri-spine horseshoe crab off Pangatalan Island in the Philippines.

From the opportunistic "have-a-go" approach of octopuses to "accessory males" that supply female anglerfish with a lifetime of sperm, author Jon Copley explores the sex lives of deep sea creatures.

A new patch, which sticks to the inner lining of the cheek like an octopus sucker, effectively delivered two drugs in dogs and passed safety tests in humans.

The "yeti" crab is white and hairy, as its nickname suggests, and it thrives in hydrothermal vents in Antarctica's frigid waters.

These tiny crustaceans, also known as boxer crabs, use the venomous anenomes to protect themselves from predators and to eat with. They also wave them around while fighting with each other.

As Cold War tensions rose, Gregory Bateson was busy observing two solitary octopuses learning to live together in a single tank — and it gave him an idea about managing geopolitical relations.