Latimeriidae

Latimeriidae is a family of coelacanths within the order Coelacanthiformes, a group of extinct and living lobe-finned fishes in the subclass Sarcopterygii. The family currently includes the living genus Latimeria, which contains two recognized species, Latimeria chalumnae and Latimeria menadoensis, as well as multiple extinct genera known from fossil remains. The two living species are found in distinct deep-water regions: L. chalumnae in the western Indian Ocean near Africa and the coast of Madagascar, and L. menadoensis around Indonesia.

Coelacanths of Latimeriidae are characterized by lobed pectoral and pelvic fins supported by internal skeletons, cosmoid scales, and a unique intracranial joint that allows the skull to move independently from the braincase. They possess a heterocercal tail and a number of features that link them to early sarcopterygians, including a braincase and sensory structures adapted to deep-water life. Their anatomy reflects an ancient lineage that has persisted with relatively little change for hundreds of millions of years.

The fossil record of Latimeriidae extends from the Devonian period and provides important insights into the early evolution of lobe-finned fishes, including the relationship between coelacanths and the ancestry of tetrapods. The Latimeriidae lineage survived major extinction events and persisted into the modern era, with living representatives that are among the rarest and most studied marine vertebrates.

Ecology and behavior of Latimeriidae species are typical of deep-sea coelacanths: slow-moving, solitary predators adapted to low-light environments. Reproduction is ovoviviparous, with internal fertilization and births of relatively large, few offspring, a strategy that complements their long lifespans and stable, low-energy lifestyles. The family remains a focal point of paleontological and evolutionary research.