A research team led by NOAA marine biologists has described a new species of pocket shark from the Gulf of Mexico.
The American pocket shark (Mollisquama mississippiensis). Image credit: Michael Doosey.
The newly-discovered shark species belongs to the previously monotypic genus Mollisquama.
Named the American pocket shark (Mollisquama mississippiensis), the creature was captured in February 2010 in the Gulf of Mexico.
“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,” said team member Dr. Henry Bart, director of the Tulane Biodiversity Research Institute.
“In the history of fisheries science, only two pocket sharks have ever been captured or reported,” added team leader Dr. Mark Grace, a researcher in the NMFS Mississippi Laboratories of the NOAA.
“Both are separate species, each from separate oceans. Both are exceedingly rare.”
The only other known specimen of Mollisquama was collected in the Eastern Pacific Ocean in 1979, and was described as a species, named Mollisquama parini, in 1984.
“There were notable differences between the original Pacific Ocean specimen and the newer specimen from the Gulf of Mexico,” the scientists said.
“Those differences include fewer vertebrae and numerous light-producing photophores that cover much of the body.”
“The two species both have two small pockets that produce luminous fluid (one on each side near the gills).”
The team examined external features of the American pocket shark with a dissecting microscope, studying radiographic (X-ray) images and high resolution CT scans.
The most sophisticated images of internal features of the shark were produced at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France, which uses the most intense source of synchrotron-generated light in the world to produce X-rays 100 billion times brighter than the X-rays used in hospitals.
“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,” Dr. Bart said.
The team’s paper was published in the journal Zootaxa.
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Mark A. Grace et al. 2019. A new Western North Atlantic Ocean kitefin shark (Squaliformes: Dalatiidae) from the Gulf of Mexico. Zootaxa 4619 (1); doi: 10.11646/zootaxa.4619.1.4
