coelacanth: see lobefin; fish.

Any lobe-finned bony fish of the order Crossopterygii. Members of an extinct suborder are considered to have been the ancestors of land vertebrates. Modern coelacanths (genus Latimeria) are deep-sea fishes with hollow fin spines. They are powerful, heavy-bodied predators, with highly mobile, limblike fins. They average 5 ft (1.5 m) in length and weigh about 100 lbs (45 kg). Coelacanths appeared about 350 million years ago and were thought to have become extinct 80 million years ago until one was caught in 1938 near the southern coast of Africa in the Indian Ocean. A second species was discovered living near Indonesia in 1998.

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