Long-lost giant fish from Amazon rediscovered in 145 year old literature

Arapaima fish probably has 2 species, not 1

April 2013. A species of giant Amazonian fish, whose existence was first established in a rare 1829 monograph, only to be lost to science some 40 years later has been rediscovered - Sort of. A professor at the State University of New York, Dr. Donald Stewart found evidence in the monograph of a second species belonging to the genus Arapaima, air-breathing giants that live in shallow lakes, flooded forests and connecting channels in the Amazon River basin. 

A comparison showing an A. agassizii skeleton together with an

 Arapaima arapaima from Guyana. Courtesy of Dr. Donald Stewart. 

Only 1 species?

For 145 years, biologists have thought that Arapaima consisted of a single species whose scientific name is A. gigas. But Stewart rediscovered a second species that he describes in the March issue of the journal "Copeia," published by the American Society of Ichthyologists and Herpetologists. 

Forgotten

"In a sense, this forgotten fish has been hiding in plain sight in this old monograph but that monograph is so rare that it now resides only in rare book collections of a few large museums," Stewart said. "I was truly surprised to discover drawings that revealed a fish very different from what we consider a typical Arapaima." 

Part of the apparently rare fish's story remains a mystery, however, as scientists don't know if it still exists in the wild. "Scientists have had the impression that Arapaima is a single species for such a long time that they have been slow to collect new specimens. Their large size makes them difficult to manage in the field and expensive to store in a museum," Stewart said. 

Continued: http://www.wildlifeextra.com/go/news/arapaima-amazon.html