Coelacanths are often cited as so called living fossils. The first extant coelacanth (pronounced seel-a-canth) was discovered in 1938 and named Latimeria chalumnae after its discoverer, Miss Marjorie Courtenay-Latimer, pictured at top above. The species was described by Professor J.L.B. Smith in 1939. Until recently, the living coelacanths were known only from the western Indian Ocean, mostly from near the Comoros Islands. In 1997, however, coelacanths were captured in Indonesia, some 6,000 miles east of Comoros. While the Indonesian' specimens resemble those from the Indian Ocean, comparative DNA analyses have shown significant genetic differentiation, suggesting several millions of years of evolutionary separation. The Indonesian species is named Latimeria menadoensis. Before the discovery of living coelacanths, they were known only from the fossil record, and were believed to have met with extincttion some 65 million years ago (mya) along the dinosaurs disappeared. The fossil record extends from about 80 mya to as far back as 360 mya; here is a Mississippian age Caridosuctor fossil coelacanth from the Famous Bear Gulch Formation of Montana, and a Coccoderma Jurassic coelacanth from the Solnhofen Limestone of Germany. |