A long-snouted predatory dinosaur from africa and the evolution of spinosaurids
Sereno PC,
Beck AL,
Dutheil DB,
Gado B,
Larsson HCE,
Lyon GH,
Marcot JD,
Rauhut OWM,
Sadleir RW,
Sidor CA,
Varricchio DD,
Wilson GP,
Wilson JA.
P. C. Sereno, A. L. Beck, H. C. E. Larsson, J. D. Marcot, C. A. Sidor, J. A. Wilson, Department of Organismal Biology and Anatomy, University of Chicago, 1027 East 57th Street, Chicago, IL 60637, USA. D. B. Dutheil, Laboratoire de Paleontologie,
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.
PMID: 9812890 [PubMed - as supplied by publisher]