The blunt sixgill shark is a primitive shark that resembles extinct sharks more than living sharks. Its snout is broad and blunt, colored brown, brown, or black, and can reach lengths of up to 20 feet.

"Goblin sharks are often referred to as “living fossils” because they are the only living members of the Mitsukurinidae family that existed millions of years ago. They have a very long, flat snout and prominent jaws that can extend to the tip of their snout when feeding."

"Greenland sharks not only survive in the depths, but they also have the longest lifespan compared to all sharks, estimated to be between 250 and 500 years. They are large sharks, and their length typically reaches about 21 feet."

"This shark is one of the smallest sharks that ever existed, measuring only between 16 and 22 inches long. They are dark brown but have photophores on their underside, which are organs that appear as glowing spots."

Some of the most unique sharks are the swell sharks. Swell sharks are a species of catshark that live in the Pacific Ocean, between California and southern Mexico. Large sharks can be found at depths of 1,500 feet and inhabit rocky bottoms where they can hide in crevices all day.

"The other glowing shark is the kitefin shark. The kitefin shark lives in several populations around the world in tropical and subtropical waters near the seabed. They are mostly found at depths between 660 and 2,000 feet, although some have also been caught at depths of 5,900 feet."

The newly discovered deep-sea shark species found in 2010 is the ninja lanternshark. The ninja lanternshark lives along the continental slope in the eastern Pacific Ocean, and its depth ranges from 2,740 to 4,735 feet.

"Portuguese dogfish is the deepest deep-sea shark and is found at a depth of 12,057 feet. They are widely distributed around the world, but are most often found near the deepest ocean floors. Portuguese dogfish are sleeping sharks and usually have a length of about 3 feet."

The basking shark lives at great depths, making it rarely seen by humans, with fewer than a hundred observed since this species was first discovered in 1976. Like the basking shark and whale shark, the basking shark is a filter feeder and primarily consumes plankton.