By Richard Conniff
For more than 200 years, skeptics have been announcing the end of the great age of species discovery—and the end, in particular, for finding anything really big. But giant species somehow just keep showing up.
Now scientists are reporting the discovery of a river monster,Arapaima leptosoma, in Brazil’s Amazonas State. It’s a new species, described from a single specimen measuring 33 inches from head to tail, in a genus that can grow to almost 10 feet and weigh up to 440 pounds.
Arapaima, also commonly known as pirarucu, is a genus of air-breathing fish that inhabit creeks and backwaters in and around the Amazon basin. They live by crushing other fish between their large bony tongue and the roof of the mouth. People prize them both for their tasty flesh and for their handsome scales, which tourists (including this writer) used to carry home incorporated in handsome necklaces and other folk art. But these huge fish are now badly overharvested, in part because it’s so easy to harpoon them when they come to surface to breathe. Arapaima gigas, for example, is listed as endangered under the Conventional on International Trade in Endangered Species, or CITES.
The only known specimen of the new species, Arapaima leptosoma, turned up not in the wild, but at the Instituto Nacional de Pesquisas da Amazônia, a research facility in Manaus. A collector originally caught it in 2001, at the confluence of the Solimões and Purus rivers 200 miles west of the city. Until recently, though, everyone assumed it was simply another Arapaima gigas, because scientists said that was the only species in the genus. But then Donald Stewart arrived in Manaus for a closer look—and soon realized he was seeing something entirely new.
Now scientists are reporting the discovery of a river monster,Arapaima leptosoma, in Brazil’s Amazonas State. It’s a new species, described from a single specimen measuring 33 inches from head to tail, in a genus that can grow to almost 10 feet and weigh up to 440 pounds.
Arapaima, also commonly known as pirarucu, is a genus of air-breathing fish that inhabit creeks and backwaters in and around the Amazon basin. They live by crushing other fish between their large bony tongue and the roof of the mouth. People prize them both for their tasty flesh and for their handsome scales, which tourists (including this writer) used to carry home incorporated in handsome necklaces and other folk art. But these huge fish are now badly overharvested, in part because it’s so easy to harpoon them when they come to surface to breathe. Arapaima gigas, for example, is listed as endangered under the Conventional on International Trade in Endangered Species, or CITES.
The only known specimen of the new species, Arapaima leptosoma, turned up not in the wild, but at the Instituto Nacional de Pesquisas da Amazônia, a research facility in Manaus. A collector originally caught it in 2001, at the confluence of the Solimões and Purus rivers 200 miles west of the city. Until recently, though, everyone assumed it was simply another Arapaima gigas, because scientists said that was the only species in the genus. But then Donald Stewart arrived in Manaus for a closer look—and soon realized he was seeing something entirely new.
