“Eagle Shark” floated in the oceans 93 million years ago

Yet researchers are convinced that Aquilolamna milarcae moved slowly. “It can be compared to a glider kite, not at all suitable for swimming fast and chasing prey,” said Vullo.

In addition to its slow movement, its large, short head and the fact that no teeth were found in its jaw, indicate that the eagle shark may have fed on plankton rather than being a predator.

In the Cretaceous period where Aquilolamna lived, the only creatures known to filter plankton from the water were large bony fishes of the Pachycormidae family, while the eagle shark had a skeleton of cartilage, like modern sharks and rays.

The two groups, the Pachycormidae and Aquilolamnadisappear in the great wave of extinction that marked the end of the Cretaceous 66 million years ago, when a huge meteorite struck the Earth and, among other things, greatly reduced the presence of plankton in the oceans.

The ecological niche of the Pachycormidae is occupied in the Tertiary, the geological period following the Cretaceous, by large planktonic sharks such as the current whale shark and the basking shark. “The eagle shark has been gradually replaced by manta rays and reef manta rays, which develop in the early Tertiary period,” said Vullo.

The fact that no teeth were found in the jawbone of the fossil specimen suggests that the species had very small teeth. Vullo hopes that future discoveries will allow us to make the connection between Aquilolamna and isolated from tiny teeth previously found in deposits of the same age. They might belong to “a pretty confusing plankton eater,” and it just might be the eagle shark.