A newly discovered species of prehistoric freshwater shark has been named after a 1980s arcade game Galaga.
US palaeontologists have introduced us to Galagadon nordquistae, a newly discovered species of freshwater shark from around 67 million years ago.
Sharks have been around for a long, long time, and of all the creatures that roam the Earth today they’re one of the few that have remained largely unchanged for tens of millions of years. The newly discovered shark swam in the rivers of what is now South Dakota, US, living alongside iconic dinosaur species such as T. rex.
It's been named Galagadon, after the 1981 Japanese-US game Galaga, because its teeth resemble the spaceships in the game.
The specimen is described in the Journal of Palaeontology.
"It may seem odd today, but about 67 million years ago, what is now South Dakota was covered in forests, swamps and winding rivers," said co-author Terry Gates, from North Carolina State University.
The tiny teeth - each measuring less than a millimetre across - were discovered in the sediment left behind when palaeontologists at the Field Museum in Chicago uncovered the bones of "Sue," currently the most complete T. rex specimen ever described.
However, said Dr Gates, "Galagadon was not swooping in to prey on T. rex, Triceratops, or any other dinosaurs that happened into its streams. This shark had teeth that were good for catching small fish or crushing snails and crawdads (crayfish)."
Evidence of the shark was found in the same dirt where scientists discovered the world’s most complete Tyrannosaurus rex skeleton, nicknamed Sue, now on display at The Field Museum in Chicago, said the N.C. State release.
The classic arcade game, Galaga, pit insectoid alien spaceships against a spacecraft at the bottom of the screen - controlled by the player - which bears a strong resemblance to the shark teeth.
“It amazes me that we can find microscopic shark teeth sitting right beside the bones of the largest predators of all time,” Gates said in a statement. “These teeth are the size of a sand grain. Without a microscope you’d just throw them away.”
Galagadon nordquistae, as it has been named, was relatively small - about 30cm (12ins) to 45cm (18ins) - and was related to modern carpet sharks, such as the wobbegong.
Despite its diminutive size, Gates sees the discovery of Galagadon as an important addition to the fossil record.
"Every species in an ecosystem plays a supporting role, keeping the whole network together. There is no way for us to understand what changed in the ecosystem during the mass extinction at the end of the Cretaceous without knowing all the wonderful species that existed before."