A team of US researchers has identified a new species of pocket shark that can glow in deep ocean.

Collected in the eastern Gulf of Mexico in 2010, the male kitefin shark only measures 15 cm in length and has five distinctive features not found in the only other known specimen of its kind.

The older specimen was captured in the Eastern Pacific Ocean in 1979 and is now housed at the Zoological Museum in St. Petersburg, Russia, the research team said in a press release last week.

Both the original Pacific Ocean specimen and the newer specimen from the Gulf of Mexico have a tiny pocket gland on each side of their body near the gills that can produce luminous fluid, which scientists believe is a means of attracting prey.

On top of that, the newer specimen possesses notable differences include fewer vertebrae and numerous light-producing photophores that cover much of its body, according to the researchers.

“The fact that only one pocket shark has ever been reported from the Gulf of Mexico, and that it is a new species, underscores how little we know about the Gulf – especially its deeper waters – and how many additional new species from these waters await discovery,” said Henry Bart, an author of the study at the Tulane University in the US state of Louisiana.

“Both are separate species, each from separate oceans. Both are exceedingly rare,” said study author Mark Grace of the National Marine Fisheries Service-Mississippi Laboratories of the National Oceanic and Atmospheric Administration.

The new findings were published recently in the animal taxonomy journal Zootaxa.