Isn’t this X-ray beautiful?
It’s a young male.
Yes, as far as I know those ribs are the cartilaginous skeleton of this animal, photographed by Ken Jones and displayed everywhere. This photo and description comes from Our Amazing Planet, for it’s a new species, a “pancake stringray” described as looking like a “pancake with noses”.
The team’s work in the Upper Amazon confirmed the new genus, Heliotrygon, and the two new species, Heliotrygon gomesi and Heliotrygon rosai. Besides their pancake-like appearance, both rays are big, have slits on their bellies and a tiny spine on their tails.
Most of Lovejoy and Carvalho’s specimens came from the Rio Nanay, near Iquitos, Peru. Their discovery brings the total number of neotropical stingray genera — from an area that also includes tropical Mexico, the West Indies and Central America — to four. Before their study, the last new genus of stingrays from the Amazon was described in 1987.
Here’s a live one:
Both species, and I’m not sure which one is above, are described in an article in Zootaxa from last year. The reference is below but, sadly, I have no free access to the article (the link below takes you to the abstract). This is the first failed biology search I’ve had at my University library!
deCarvalho, M. R. and N. R. Loveyoy. 2011. Morphology and phylogenetic relationships of a remarkable new genus and two new species of Neotropical freshwater stingrays from the Amazon basin (Chondrichthyes: Potamotrygonidae). Zootaxa 2776:13-48.