Swimming through the shadowy waters off Palau, scuba divers watched life on a coral reef after dark. One reddish sea creature with 17 "feather"-like arms caught their attention - and for good reason.

In a laboratory aquarium in northern Russia, a fluorescent green sea creature with 14 tentacles moved about. It ate, grew and eventually reproduced. A patient scientist watched the process, ...

Scientists found a “large,” “cryptic” sea creature with a “whip-like tail” in the Atlantic Ocean and discovered a new species, study said. Photo from Getty / iStockphoto In the crystal waters of the ...

Scientists scuba diving at night in Palau found a “cryptic” sea creature with 17 arms and discovered a new species, a study said. Photo from Chen Irene via Unsplash Swimming through the shadowy waters ...