Tropical to temperate latitudes of the western Indian Ocean
Deep caves and rocky reefs
Critically Endangered (Very Highly Vulnerable To Extinction)
Order Coelacanthiformes (coelacanths), Family Latimeriidae (coelacanths)
The coelacanth is a rare marine fish that is a living representative of an ancient lineage of formerly common fishes. This and the closely related Indonesian coelacanth (Latimeria menadoensis) have several unique physical characteristics that few or no other living species have. Coelacanths were thought to be extinct for tens of millions of years, so the discovery of this species in the 1930s and the subsequent discovery of the Indonesian coelacanth in the 1990s represent some of the most significant natural history discoveries of recent times.
Coelacanths live in deep waters off of southeastern Africa. Only once fishers started fishing deeper and deeper was this species discovered. Before that time, this entire family of fishes was only known from fossils. Coelacanths reach lengths over 6.5 feet (2 m) and are nocturnal predators. They spend daylight hours hiding in caves and other dark spaces and hunt small bony fishes, squids, and other invertebrates at night. This species is noted for its limb-like fins. The coelacanth, the Indonesian coelacanth, and the lungfishes together make up a group known as the lobe-finned fishes. Their fins are attached to short limbs rather than directly to the body like in most species. These species are the closet fish relatives to the tetrapods (amphibians, reptiles, mammals, and birds). In fact the lobe-finned fishes are more closely related to the tetrapods than to the other fishes. Live coelacanths have been observed using their lobed fins in a paddle-like fashion, almost as if they are walking through the water column.
The coelacanth and Indonesian coelacanth are the only two vertebrates that have a jointed skull. This adaptation apparently allows them to open their mouths wider than they would be able to otherwise, improving their predation ability. Coelacanths reproduce via internal fertilization and give birth to relatively well-developed live young. As soon as they are born, juvenile coelacanths do not receive any further parental care and are ready to begin a predatory lifestyle.
As a result of its small geographic range, low natural numbers, and vulnerability to newly arising deep-sea fisheries, the coelacanth is considered to be critically endangered (very highly vulnerable to extinction) by marine scientists. Only a relatively small number of specimens have ever been collected or observed, and without careful management of human activities throughout its range, this species could easily be lost. Given the fact that it has survived for millions of years, the loss of this species as a result of human activity would represent a shameful loss of natural heritage.
Oceana joined forces with Sailors for the Sea, an ocean conservation organization dedicated to educating and engaging the world’s boating community. Sailors for the Sea developed the KELP (Kids Environmental Lesson Plans) program to create the next generation of ocean stewards. Click here or below to download hands-on marine science activities for kids.