Atlantic sixgills= A New Species of Shark

FOR DECADES, SCIENTISTS THOUGHT THAT all bigeye sixgill sharks, named for their distinct number of gills (most sharks only have five), belonged to the same species, Hexanchus nakamurai. But new research shows that sixgill sharks swimming in the waters of the Atlantic Ocean are actually a different species from those in the Indian and Pacific Oceans. 

A team of marine biologists led by Toby Daly-Engel, the director of the Shark Conservation Lab at the Florida Institute of Technology, analyzed 1,310 base pairs of two mitochondrial genes found in sharks from the three different oceans. Their results, published in the journal Marine Biodiversity, prove that the Atlantic sixgills are indeed a different type of shark. The newly recognized species is called Hexanchus vitulus, the Atlantic sixgill shark.READ MORE