New species of see through fish discovered in Amazonia

The blue-bellied night wanderer species name is Cyanogaster noctivaga, Cyanogaster meaning blue belly and noctivaga meaning night wanderer. It is 17mm long, and in addition to its bright blue belly, it has large eyes, and unusual-looking snout, mouth and

Tiny fish represents a new genus
April 2013. It is only 7mm longer than the world's smallest fish, and seems to only appear at night, but the bright blue belly of a tiny Amazonian fish caught the eye of a team of scientists who spotted it was a new species and genus.

'It is a strange little animal, completely transparent with an otherwise unique colour pattern,' says The Natural History Museum fish expert (ichthyologist) Ralf Britz. Britz worked with expedition leader Monica Toledo-Piza, George Mattox and Manoela Marinho from the University of Sao Paulo (USP), Brazil, on the scientific expedition in Oct 2011.

The blue-bellied fish was discovered in the Rio Negro, the largest tributary of the Amazon River. This area of the Amazon basin is probably one of the best explored, so finding not only a new species but a new genus too, was quite a surprise.

Hard to capture - Only found at night
The team could only find the blue-bellied fish in one place on the Rio Negro, and it could only be found at night. 'The fish appeared as a fast swimming blue streak in the net,' says Britz.

Live (bottom) blue-bellied night wanderer fish with

 its full colour on show. 

Once dead and preserved, the colour is lost (top).

Not only was the fish hard to find, but as soon as it was lifted out of the net it died. In order to get a photo of the live fish to show its unique colouration, Britz had to improvise.

'I set up a photo tank right at the shoreline with the camera and flashes ready to shoot. Then my colleague George and I went into the water and pulled the net towards the shoreline. I then used a large spoon to scoop them out of the net and transfer them into the photo tank without lifting them out of the water.'

Continued:  http://www.wildlifeextra.com/go/news/see-through-fish.html