What is a Frilled Shark?

The Frilled Shark is a very unusual type of shark which most biologists believe is a primitive remnant of earlier shark species. Superficially resembling an eel, the Frilled Shark has an elongated body with the trademark six gills of a shark and distinctive three pronged teeth. The scientific name of the Frilled Shark is Chlamydoselachus anguineus, and the common name probably originates from the gills, which stick out more than normal gills, resembling a frilled collar.

It is believed that there is only one species in the Chlamydoselachus genus, although there may be additional species. Some biologists have suggested that the African Frilled Shark is actually a species separate from other Frilled Sharks. Reaching up to a length of six feet (two meters), the dull brown Frilled Shark is found in deep waters all over the world, where it lives on squid and other deep water dwelling fish. The Frilled Shark is known to be oviviparous, which means that the female retains the eggs inside her body until they hatch, although the gestation period is not known for certain. Studies off the coast have Japan have suggested that it may be as long as 3 ½ years, making it the longest gestation period of any animal on Earth.

The Frilled Shark has several identifying features in addition to the long, eel like body. The caudal or tail fin has only a vestigial lower lobe, meaning that the upper lobe of the caudal fin is much larger and more clearly defined. The Frilled Shark has a single small dorsal fin, and a larger and much more pronounced anal fin. The design of the fins may allow the Frilled Shark to rapidly propel itself at prey, and the large mouth of the Frilled Shark allows it to eat very large prey animals. Numerous dead specimens have been studied: so far, no Frilled Shark has survived in captivity.

The fossil record suggests that Frilled Sharks have been around for thousands of years: in fact, the Frilled Shark was initially thought to be extinct, until specimens were recovered in Japan during the 19th century. Due to their shy natures and bottom dwelling habits, Frilled Sharks are imperfectly understood. Biologists still argue over the proper taxonomy of the animal, although most biologists do agree that the Frilled Shark is a threatened species, and may be at serious risk of extinction.

The bizarre shape of the Frilled Shark may be the culprit behind “sea serpent” stings, especially off the coast of Japan. Cryptozoologists might be disappointed by this somewhat mundane explanation, but in actuality spotting a Frilled Shark is a cause for celebration, as the deep dwelling sharks rarely come near the surface of the ocean. In addition, Frilled Sharks represent one of the few animal species which has evolved very little over the millennia, and could almost be viewed as an evolutionary throwback. While seeing a mythological beast would be a thing to remember, a Frilled Shark just might be the next best thing.

The frilled shark is a rare, deep-sea shark known for its eel-like body and frilly gills. It inhabits depths of over 500 meters in the Atlantic and Pacific Oceans. This elusive creature is often found near the outer continental shelf and upper to middle continental slopes, making sightings by humans quite uncommon.

Frilled sharks employ a unique hunting strategy. They bend their bodies and lunge forward like a snake to capture prey. Their diet consists mainly of squid, bony fish, and other sharks. Their long, flexible jaws allow them to swallow prey whole, and their 300 trident-shaped teeth prevent escape.

Frilled sharks are distinguished by their slender, eel-like bodies, which can grow up to 2 meters in length. They have six pairs of gill slits with frilly edges, which are the origin of their name. Their mouths are wide and terminal, equipped with multiple rows of backward-facing teeth, and their coloration is a dark brown or gray.

Frilled sharks are rarely encountered by humans due to their deep-sea habitat. They are considered living fossils, with few evolutionary changes over millions of years. Encounters are usually incidental, occurring during deep-sea trawling operations or scientific research expeditions aimed at studying deep-sea biodiversity.

Frilled sharks have a lengthy gestation period, which can last up to 3.5 years, one of the longest known among vertebrates. They are ovoviviparous, meaning embryos develop inside eggs that remain within the mother's body until they hatch. A litter can range from 2 to 15 pups, which are born fully developed.

According to the International Union for Conservation of Nature (IUCN), frilled sharks are classified as "Near Threatened." Their deep-sea habitat offers some protection from human activities, but they are still affected by accidental bycatch in fisheries. Conservation efforts are important to monitor and protect this ancient species from further decline.