A Long-Snouted Predatory Dinosaur from Africa and the Evolution of Spinosaurids

TLDR

Fossils from the Aptian Tenere Desert in central Niger shed new light on spinosaurid theropods, a distinctive piscivorous group. The new African spinosaurid, with an elongated, laterally compressed snout and blade‑shaped vertebral spines forming a low hip sail, represents a new genus and species; phylogenetic analysis places its enlarged thumb claw and robust forelimb as Jurassic traits, while its close kinship with European Baryonyx implies Early Cretaceous dispersal across the Tethys seaway.

Abstract

Fossils discovered in Lower Cretaceous (Aptian) rocks in the Tenere Desert of central Niger provide new information about spinosaurids, a peculiar group of piscivorous theropod dinosaurs. The remains, which represent a new genus and species, reveal the extreme elongation and transverse compression of the spinosaurid snout. The postcranial bones include blade-shaped vertebral spines that form a low sail over the hips. Phylogenetic analysis suggests that the enlarged thumb claw and robust forelimb evolved during the Jurassic, before the elongated snout and other fish-eating adaptations in the skull. The close phylogenetic relationship between the new African spinosaurid and Baryonyx from Europe provides evidence of dispersal across the Tethys seaway during the Early Cretaceous.