Coelacanthiformes (subclass Crossopterygii, superorder Coelacanthimorpha) An order of bony fish thought to have been extinct for 65 million years (since the end of the Mesozoic Era) until the discovery of the coelacanth Latimeria chalumnae off S. Africa in 1938 (see LATIMERIIDAE). Both fossil and living coelacanths are bulky marine fish with a diphycercal or tri-lobed tail fin, the second dorsal, anal, pectoral, and pelvic fins being very unusual as they are supported by movable stalks or lobes. The much smaller fossil species lived from the Devonian to the Cretaceous. They were initially freshwater fish, but in the Triassic marine representatives also evolved.

Coelacanthiformes (class Osteichthyes, subclass Crossopterygii) Order of bony fish thought to have been extinct for 50 million years (since the end of the Mesozoic Era) until the discovery of the coelacanth (Latimeria chalumnae) off S. Africa in 1938. Both fossil and living coelacanths are bulky marine fish with a diphycercal or tri-lobed tail fin; the second dorsal, anal, pectoral, and pelvic fins are very unusual as they are supported by movable stalks or lobes. The much smaller fossil species lived from the Devonian to the Cretaceous. They were initially freshwater fish, but in the Triassic marine representatives also evolved.