Scientists have found a Cretaceous shark fossil in Mexico, it is unusual for its fins that look like wings.
Interestingly, this body shape was not previously known in sharks. This is the oldest find of the “winged” representative of the lamellar gills, which lived long before the appearance of mantas and eagle rays.
The group of lamellar gills includes two distantly related clades with different morphotypes. The first is whale and giant sharks, the second is animals with wing-like fins, manta rays and eagle rays-mobula, or stag beetles.
Until now, it was believed that long and slender outgrowths on the sides of the body, resembling wings, began to form in skate-like lamellar gills after these two clades separated. However, this find forced paleontologists to reconsider the way cartilaginous fish evolved.
Experts speculate that the shark, named Aquilolamna milarcae, fed on plankton. Her finding allowed scientists to understand that such “soaring” plate-gill fish appeared at least 30 million years earlier than previously thought.
The authors speculate that the winged shark was relatively slow. Using its long pectoral fins and tail, it glided through the water column, collecting suspended plankton in its open mouth.