Brazilian scientists claimed to have found a new fish species believed to have lurked deep in the south Atlantic Ocean for over 150 million years.

The fish, of the Chimaera genus (search), is about 12-16 inches long and is found at depths of 1,300 to 2,000 feet, scientists said Thursday.

"This is a fantastic discovery, because before this we believed there were no Chimaera off the Brazilian coast," said ichthyologist Jules Soto, who discovered the fish.

Soto is the curator of the Oceanography Museum at the Vale do Itajai University (search) and co-author of the fish's scientific description, which will be published in the upcoming edition of the U.S. scientific journal Zootaxa.

Soto said the fish was discovered on a Spanish fishing boat trawling off the coast of Rio de Janeiro state in 2001.

Soto said his students first photographed the Chimaera aboard the vessel as part of a research project, but they were unaware of the fish's importance and threw it back in the ocean.

Soto realized the significance of the discovery while examining the photographs.

"I could see right away it was a very different animal, just from the shape of the fins," Soto said by telephone from Santa Catarina state, 450 miles southwest of Rio de Janeiro.

It took Soto and his team two more years to locate more specimens and to complete the scientific work needed to prove it was a new species.

The fish, which Soto has named Hydrolagus mattallansi (search), has a snub nose, winglike side fins, a spiky back fin and stinger tail. It is closely related to sharks and skates.

The Chimaera can sense the presence of other animals by scanning the electromagnetic field around it, but it also has large eyes that can sense even the smallest bit of light, Soto said.

Ichthyologists called the new Chimaera an "important discovery."

"Deep water fish have been little studied here and it's very difficult to get information about that environment. The sad thing is that environment is being devastated by industrial fishing so species new to science are likely disappearing even before they are discovered," said Adriano Lima, an ichthyologist at Rio de Janeiro's National Museum.

Scientists have identified about 25,000 fish species in the world but suspect there may be as many as 40,000 yet to be discovered.

Soto said it was rare that such a large vertebrate animal should be undiscovered but that the deep waters off Brazil's coast have not been extensively explored.

He claimed to have discovered three other new species that he is still in the process of describing.

Chimaera evolved 400 million years ago during the Devonian Period and are some of the oldest fish species alive today.