The coelacanth (pronounced like "see-la-kanth"), is nicknamed "old fourlegs". It is a close relative of the ancestor of all tetrapods (four-legged creatures), including Homo sapiens.

Coelacanths are well known from the fossil record of 400 million to 75 million years ago. Several species have been identified among the finds.

Coelacanths were thought to be extinct until 1938, when one was caught off the coast of South Africa. A long search for their home ended in 1952, when they were found in the Comoro Archipelago. The species of these coelacanths is Latimeria chalumnae.

In 1998, a new species was identified when a population of coelacanths was found near Indonesia. This new species is known as the menado coelacanth (Latimeria menadoensis).

In 1975, it was discovered that the coelacanth is a live-bearer (as opposed to an egg-bearer) when a 1.5 m-long (5 ft.) mother was found to contain five young that were each a perfect 30 cm-long (1 ft.) miniature of the adult.

Adult coelacanths average 1.5 m (5 ft.) in length, and weigh about 45 kg (100 lb.). They are steel blue in colour.