Researchers have identified a rare five and a half inches long 'pocket shark' - only the second possible specimen ever found.
The common name of the species is "pocket shark," and its scientific name is Mollisquama species.
While it is small enough to fit in the pocket, it is dubbed "pocket" because of the distinctive orifice behind its pectoral fin - one of many physiological features scientists hope to better understand.
"The pocket shark we found was only 5 and a half inches long, and was a recently born male," said Mark Grace of National Oceanic and Atmospheric Administration (NOAA), lead author of the new study.
"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," said Grace.
Interestingly, the specimen Grace discovered was not found it the ocean, per se; rather in the holdings of NOAA's lab in Pascagoula, Mississippi.
It was collected in the deep sea about 305 km offshore Louisiana during a 2010 mission by the NOAA Ship Pisces to study sperm whale feeding.
Grace recruited Tulane University researchers Michael Doosey and Henry Bart, and NOAA Ocean Service genetics expert Gavin Naylor, to give the specimen an up-close examination.
A tissue sample was collected, and scientists were able to place the specimen into the genus Mollisquama.
Further genetic analysis from Naylor indicate that pocket sharks are closely related to the kitefin and cookie cutter species, fellow members of the shark family Dalatiidae.
Like other Dalatiidae shark species it is possible that pocket sharks when hungry may remove an oval plug of flesh from their prey (various marine mammals, large fishes and squid).
The specimen - when compared to the 1979 specimen taxonomic description - is found to have a series of glands along the abdomen not previously noted.
"This record of such an unusual and extremely rare fish is exciting, but its also an important reminder that we still have much to learn about the species that inhabit our oceans," Grace added.
The study was published in the journal of taxonomy Zootaxa.
