It's not very often that you lump a kangaroo and a shark into the same sentence, and yet that's exactly what comes to mind when talking about the rare, cute pocket shark that was discovered deep in the Gulf of Mexico.

Though the "pocket shark" (Mollisquama sp.) is not named as such for having a joey-like kangaroo pouch. Rather, it has distinct orifice behind its pectoral fin, and is small enough to, well, fit in your pocket.

"The pocket shark we found was only 5 and a half inches long, and was recently born male," lead author Mark Grace said in a news release. "Discovering him has us thinking about where mom and dad may be, and how they got to the Gulf. The only other known specimen was found very far away, off Peru, 36 years ago."

Interestingly, the new specimen wasn't actually found in the ocean, but lumped in with a bunch of other sea creatures in a lab freezer. The shark was collected in the deep sea about 190 miles off the Louisiana coast during a 2010 mission to study sperm whale feeding. The researchers uncovered the sample years later and after taking a closer look, realized they had stumbled upon something remarkable.

The pocket shark turned out to be only the second of its species ever seen.

The researchers conducted genetic analysis on the pocket shark, and found that the shark is closely related to the kitefin and cookie cutter species, fellow members of the shark family Dalatiidae. Like other Dalatiidae shark species, it's possible that pocket sharks, when hungry, may remove an oval plug of flesh from their prey, which may include marine mammals, large fish and squid.

"The record of such an unusual and extremely rare fish is exciting, but it's also an important reminder that we still have much to learn about the species that inhabit our oceans," said Grace.

The findings were published in the journal Zootaxa.

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