Coelacanthiformes
Size – average 6.5 ft
Weight – around 200lb
They have unique characteristics compared to other living fish. These include the “rostrum organ” which is located in their snout and it part of their electro-sensory system. An intracranial joint or hinge in the skull that allows the anterior portion of the skull to swing upward which gives the fish a much larger mouth is another characteristic exclusively found in Coelacanths.
They primarily live near the Comoros Islands, the Western Indian Ocean between Madagascar and the East Coast of Africa. They can also be found along the East African Coast and in waters surrounding Indonesia. They are found in depths around 500-800ft off of steep rocky slopes of volcanic islands. They can sometimes be found beneath ledges and in shallow caves.
Coelacanths are predatory fish that primarily feed on small fish and squid. They have been observed hunting during both day and night, using their large, bony jaws and powerful jaws to capture prey. They are also known to feed on crustaceans and mollusks.
Coelacanths are relatively solitary creatures and are not known to exhibit much social behavior. They are mostly active at night and spend most of their time in deep waters, typically between 180 and 600 meters. They are slow-moving fish and are not known to migrate over long distances. Coelacanths are also known to be able to survive in low oxygen environments by adjusting their blood chemistry. They are also able to control the buoyancy of their body by adjusting the amount of oil in their lungs. This allows them to hover in the water column, making them difficult for predators to catch.
They have two different species with the order of Coelacanthiforms: West Indian Ocean Coelacanth and the Indonesian Coelacanth.
They are the oldest known lineage of the lobe-lined fish and tetrapods and are closely related to lungfish and tetrapods.
The West Indian Ocean Coelacanth is a critically endangered species.
They are considered a “living-fossil” to many scientist because it was the only member remaining of a taxon which is only known from fossils.
They were believed to have gone extinct around 66 million years ago but was rediscovered in 1938 of the coast of South Africa.
https://www.nationalgeographic.com/animals/fish/facts/coelacanths
