Researchers discovered four new "killer sponges" that are straight out of a nightmare and living at the bottom of the sea.

Carnivorous sponges were first discovered two decades ago , but since then only seven species have been discovered in the northeastern Pacific, a Monterey Bay Aquarium Research Institute news release reported.

"A far cry from your basic kitchen sponge, these animals look more like bare twigs or small shrubs covered with tiny hairs. But the hairs consist of tightly packed bundles of microscopic hooks that trap small animals such as shrimp-like amphipods," the news release reported.

Within a few hours of a creature getting caught in these barbs the sea sponge starts to digest it; it takes only a few days for the sponge to digest its prey, which are usually shrimp-like amphipods.

A research team videotaped the carnivorous sponges consuming their prey. When samples were taken back to the lab the researchers discovered "numerous crustacean prey in various states of decomposition," MBARI marine biologist Lonny Lundsten said in the news release.

Most sea sponges eat only bacteria and single-celled organisms; the sponges possess special cells, dubbed choancytes, which create a flow of water that draws in bacteria and other organisms. The cells have "whip-like tails" that they use to manipulate the water.

"To keep beating the whip-like tails of the choancytes takes a lot of energy. And food is hard to come by in the deep sea. So these sponges trap larger, more nutrient-dense organisms, like crustaceans, using beautiful and intricate microscopic hooks,"

The new "spiky" sponges' genus has been named Asbestopluma. One of the newly-discovered species was named Asbestopluma monticola  and was found at the top of an extinct volcano. Asbestopluma rickets, another new species was found off the shore of Southern California; the sponge was named after biologist Ed Ricketts, who was portrayed in John Steinbeck's book "Cannery Row." The researchers could not find any animals trapped in this specimen, suggesting it could have the ability to feed off bacteria.

The new species Cladorhiza caillieti  was found on lava flows along the Juan de Fuca Ridge offshore from Vancouver Island. The finals species, Cladorhiza evae, was found near a hydrothermal vent on the "Alarcon Rise, off the tip of Baja California," the news release reported.

"Numerous additional carnivorous sponges from the Northeast Pacific (which have been seen and collected by the authors) await description, and many more, likely, await discovery," the authors wrote in their paper, the news release reported.

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