A new basal sauropod dinosaur from the middle Jurassic of Niger and the early evolution of sauropoda.

Background: The early evolution of sauropod dinosaurs is poorly understood because of a highly incomplete fossil record. New discoveries of Early and Middle Jurassic sauropods have a great potential to lead to a better understanding of early sauropod evolution and to reevaluate the patterns of sauropod diversification.

Principal Findings: A new sauropod from the Middle Jurassic of Niger, Spinophorosaurus nigerensis n.