Xenoposeidon

Xenoposeidon (meaning "strange or alien Poseidon", in allusion to Sauroposeidon) is a genus of rebbachisaurid sauropod dinosaur from the Early Cretaceous of England, living about 140 million years ago. It is known from a single partial vertebra with unusual features, unlike those of other sauropods. This bone was first discovered in the early 1890s but received little attention until it was found by University of Portsmouth student Mike Taylor, who formally described and named it in 2007 with Darren Naish.

==Description== thumb|150px|left|Close up of v-shaped laminae on NHMUK R2095. The feature of the wrinkles are unknown Xenoposeidon is based on BMNH R2095, a partial posterior back vertebra. The specimen lacks the anterior face of the centrum and the upper portion of the neural arch. The centrum is estimated at long, and the height of the preserved portion of the vertebra is . The average diameter of the posterior face of the centrum is , with a concave surface. This concavity is deep enough to suggest that the anterior faces of vertebrae from this part of the dinosaur's spine would have been convex to articulate with such a shape.