Armed response
Armoured dinosaurs are widely recognized for their tail weapons, which include spikes in stegosaurs and tail clubs in ankylosaurs. In this week’s issue, Alexander Vargas and his colleagues present a new species of ankylosaur with an unusual tail weapon that resembles an Aztec war club. Found in southern Chile, the nearly complete skeleton of Stegouros elengassen dates to around 75 million years ago. The large tail weapon consists of seven pairs of flattened, bony deposits fused together in a frond-like structure. The researchers were able to determine that Stegouros is specifically related to the other Gondwanan ankylosaurs Kunbarrasaurus from Australia and Antarctopelta from Antarctica. They suggest that different branches of the ankylosaur family tree may have existed in Laurasia and Gondwana following the final separation of these supercontinents in the late Jurassic period.
https://www.nature.com/nature/volumes/600/issues/7888
