<i>Xilousuchus sapingensis</i> fossil (IMAGE) University of Washington Caption This drawing depicts the skull and 10 neck vertebrae from the fossil of an archosaur called Xilousuchus sapingensis. The elongated spines on rearward vertebrae indicate the presence of a "sail" on the animal's back. Credit Sterling Nesbitt Usage Restrictions News use only, with credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.