10 weird creatures found in the deep sea .

If you're looking for bizarre creatures that defy explanation, there is no better place to look than the deep sea. Every year, researchers capture incredible footage of alien-looking animals and strange new species lurking in the deep, and this year was no different. Here is our list of the top 10 weirdest deep-sea creatures seen in 2021.

Blood-red jellyfish
The mysteries red jelly may be a new species previously unknown to science, NOAA researchers say.

This mysteries red jelly may be a new species previously unknown to science, NOAA researchers say. (Image credit: NOAA)
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In August, researchers with the National Oceanic and Atmospheric Administration (NOAA) announced the discovery of a brand-new and unnamed species of blood-red jellyfish. The dark red jelly likely belongs to the genus Poralia, according to the researchers.

They first spotted the new jelly on July 28 using a remotely operated vehicle (ROV) at a depth of around 2,300 feet (700 meters) just off the coast of Newport, Rhode Island. Other animals, including other cnidarians (jellyfish & corals), ctenophores (comb jellies), crustaceans and Actinopterygii (ray-finned fishes), were also seen on the dive.

Lots of deep-sea creatures have evolved a similar red color because red wavelengths of light do not penetrate into the deep ocean. This means that red animals appear black because there is no red light to reflect back toward potential predators.

Read more: Mysterious blood-red jellyfish may be rare species unknown to science, researchers say