This leggy creature may look like an octopus, but it's actually an immature, or larval, tube anemone (picture of an adult tube anemone).

(Watch video of the tiny sea creatures.)

Despite being so young and only about 0.4 inch (1 centimeter) wide, the anemone larva has already begun fishing with the tentacles it will use as an adult. This specimen's dark stomach suggests it's already a successful hunter, experts say.

The anemone larva was recently inventoried during the Census of Marine Life, a series of ocean projects aimed at documenting the myriad life-forms that live in Earth's oceans. On Sunday, the census announced results of a far-ranging study of hard-to-see sea species—microscopic animals, plankton, larvae, and burrowers.

"The ocean represents about 90 percent of the habitat on the planet, in terms of volume, whereas organisms on land only live within about a hundred meters [328 feet]" of sea level, said Ron O'Dor, a senior scientist with the Census of Marine Life.

"So there is a huge volume out there capable of supporting different kinds of life."

—Ker Than

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