Helicoprion shark with a unique set of serrated teeth. 

First excavated in the Ural Mountains in the late 1800s, the jaws belong to an extinct genus that lived about 270 million years ago.

According to National Geographic, according to National Geographic, the crooked tooth is located in the lower jaw of the shark. The sharks, up to 25 feet (7.6 m) long, have no upper teeth, so as not to interfere with the arrangement of the lower serrated teeth.

Eagle shark

Eagle sharks lived 93 million years ago.

93 million years ago, in what is now Mexico, eagle sharks (Aquilolamna milarcae) glided across the sea with wing-like fins. This shark is 1.9 m wide, wider than their length, as they have a length of 1.65 m.

Wobbegong shark

Wobbegong shark lurking on the ocean floor. 

These bottom-dwelling creatures belong to the family Orectolobidae, camouflaged with colorful orange patterns. The “beards” are the sensory lobes located along their jaws.

There are dozens of species of Wobbegong sharks, spanning the eastern Indian Ocean and the western Pacific Ocean. The largest type is more than 3 m long.

Ninja lantern shark

This fish lives off the coast of Central America.

These sharks also have an interesting scientific name: Etmopterus benchleyi, after Peter Benchley, author of the book “Jaws”.

Ninja sharks are small, only about 0.5 m long. They live off the coast of Central America.

Phoebodus shark

The nearly complete skeleton of an ancient shark of the genus Phoebodus.

The Phoebodus shark is up to 1.2 m long. The first shark scales ever found date back to 450 million years ago. And, the first shark teeth were about 410 million years ago. So this shark appeared quite early.

The Phoebodus shark had three-pointed teeth, an eel-like body and a long snout, and may have looked a bit like a modern pleated shark.

Shark “bulge”

Bulky sharks can absorb water to make their bodies double in size. 

Bulge sharks often suck in huge amounts of seawater to swell to twice their normal size. This helps them intimidate predators or make it impossible for predators to pull them out of the rock crevices in which they hide.

Bulge sharks live everywhere, from the coast of California to the waters near the Philippines.

Genie dog shark

This shark is famous for its huge blue eyes.

These sharks (Squalus clarkae) are deep-water creatures that live in the Gulf of Mexico and the Western Atlantic Ocean.

The genie dog shark (Squalus clarkae) is famous for its huge blue eyes. This feature makes them look like Japanese anime characters.

Ghost shark

Sharp-nosed blue mousefish (or ghost shark). 

The pointy blue mousefish (Hydrolagus trolli) look like strange ghosts. Therefore, these elusive sharks are sometimes referred to as “ghost sharks”.

What’s odd is the stick-like organ on top of the male’s head, says Lonny Lundsten, a senior research technician at MBARI. This organ is used to position the female during intercourse.

Viper Shark

Their appearance is quite strange. 

Viper shark (Trigonognathus kabeyai) was discovered in 1986 with extremely strange triangular jaws. Their appearance is so strange that they are called alien sharks.

In addition, Viper sharks can glow. Bioluminescent organs called photocells are located underneath the undersides of these sharks.

Skinless black-mouthed cat shark

A “naked” shark pulled from the Mediterranean in July 2019 is not a new species but a completely mysterious individual with a strange condition: No teeth and no skin.

The blackmouth shark is typical for its age, growing up to 70 cm long, and has a full belly.

The gill shark

Scaly sharks have barely changed in 80 million years. 

Scaly sharks (Chlamydoselachus anguineus) get their name from their 300 3-pointed teeth, which are arranged in rows to look like frills. Frilled sharks up to 1.5 m long, up to 5 feet (1.5 m) long, attack prey larger than their own weight, using their sharp rear-facing teeth to bite fish, squid, and other species. Other sharks are twice their size.

Incredibly, these sharks have remained essentially the same for 80 million years, since before the dinosaurs went extinct. They live between 65 feet and 4,900 feet (20 to 1,500 m) underwater in the Atlantic and Pacific oceans, according to the International Union for Conservation of Nature (IUCN).