This unnamed pterosaur, likely related to the much larger azhdarchid pterosaurs of the same period, is described in a paper published in Royal Society Open Science. Two fragments of its skeleton were discovered on Hornby Island, British Columbia, providing just enough material for scientists to verify that it was not simply an adolescent version of a larger animal. Based on the telltale shape of its vertebrae, the researchers are convinced it’s not a bird, but they don’t have enough remains to say for certain where this new species would fit into the evolutionary tree. Study lead Elizabeth Martin-Silverstone told Nature, “It’s quite different from other animals we’ve studied. There hasn’t really been evidence before of small pterosaurs at this time period.” This finding is a surprise, because many paleontologists believed that pterosaurs evolved to be larger and larger as the Cretaceous wore on.

These small pterosaurs probably lived alongside the first birds. This revelation overturns one hypothesis about why the pterosaurs died out, which is that birds out-competed the small pterosaurs—leaving only the big pterosaurs, who went extinct in the aftermath of the same bolide impact that wiped out the large, non-winged dinosaurs. If birds and small pterosaurs co-existed for millions of years, it seems unlikely that the story was as simple as birds out-competing them.