Cristatusaurus

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Cristatusaurus
Pine fossils, Muséum national d'histoire naturelle, Paris

Pine fossils, Muséum national d'histoire naturelle , Paris

Temporal occurrence
Lower Cretaceous ( Aptium )
126.3 to 112.9 million years
Locations
Systematics
Theropoda
Tetanurae
Spinosauroidea
Spinosauridae
Baryonychinae
Cristatusaurus
Scientific name
Cristatusaurus
Philippe Taquet and Dale Russell , 1998
Art
  • Cristatusaurus lapparenti

Cristatusaurus is a genus of carnivorous dinosaurs from the Spinosauridae group. So far only jawbones and vertebrae are known that come from the Lower Cretaceous ( Aptium ) of the Niger . The only species is Cristatusaurus lapparenti . It is controversial whether Cristatusaurus should be classified as a valid genus or a noun dubium (dubious name), or whether the fossils actually belong to the related Baryonyx .

features

The body length is difficult to estimate because of the very few known fossils - however , Cristatusaurus could have been about ten meters in length. With a length of 13.5 centimeters, the vertebrae found are about the same size as the largest known vertebrae of Spinosaurus maroccanus .

The teeth were conical like other spinosaurids. Compared to related species, the teeth were slightly flattened laterally and slightly serrated - in contrast to the related irritator , whose teeth were unsawed. The intermaxillary bone was short compared to that of the related baryonyx and, viewed from the side, hooked.

Validity of the genre and system

The validity of this genus is disputed. The fossils cannot be clearly differentiated from the related genus Baryonyx . Various researchers use Cristatusaurus as the noun dubium (dubious name). Other researchers attribute these fossils to Baryonyx (as Baryonyx sp. ), Making Christatusaurus a more recent synonym for Baryonyx . Thomas Holtz (2004) still considers Cristatusaurus to be a valid genus, and classifies it within the Baryonychinae, a subgroup of the Spinosauridae.

Research history and naming

Fossils come from the Gadoufaoua locality of the Tegama Formation . The type material (copy number MNHN GDF 366) consists of both intermaxillary bones (premaxillary) and parts of the right upper and lower jaw. Other finds attributed to the genus include a fused pair of intermaxillary bone and a dorsal vertebra. Cristatusaurus was named in 1998 with the species Cristatusaurus lapparenti by Philippe Taquet and Dale Russell . The name Cristatusaurus means something like "comb lizard" ( Latin cristatus - "comb", Greek sauros - "lizard"). The Artepitheth lapparenti honors the paleontologist Albert de Lapparent , who contributed significantly to the understanding of the dinosaur finds in the Sahara and who supported the excavation work in 1966.

Individual evidence

  1. ↑ Thomas R. Holtz Jr .: Supplementary Information. to: Thomas R. Holtz Jr .: Dinosaurs. The most complete, up-to-date Encyclopedia for Dinosaur Lovers of all ages. Random House, New York NY 2007, ISBN 978-0-375-82419-7 , online (PDF; 184.08 kB) .
  2. ^ A b c Philippe Taquet , Dale A. Russell : New data on spinosaurid dinosaurs from the Early Cretaceous of the Sahara. In: Comptes Rendus de l'Académie des Sciences. Series IIA: Earth and Planetary Science. Vol. 327, No. 5, 1998, ISSN  1251-8050 , pp. 347-353, doi : 10.1016 / S1251-8050 (98) 80054-2 .
  3. ↑ Oliver WM Rauhut : The ?? interrelationships and evolution of basal theropod dinosaurs (= Special Papers in Palaeontology. Vol. 69). Palaeontological Society, London 2003, ISBN 0-901702-79-X .
  4. ^ Paul C. Sereno , Allison L. Beck, Didier B. Dutheil, Boubacar Gado, Hans CE Larsson, Gabrielle H. Lyon, Jonathan D. Marcot, Oliver WM Rauhut, Rudyard W. Sadleir, Christian A. Sidor, David D. Varricchio, Gregory P. Wilson, Jeffrey A. Wilson: A Long-Snouted Predatory Dinosaur from Africa and the Evolution of Spinosaurids. In: Science . Vol. 282, No. 5392, 1998, 1298-1302, doi : 10.1126 / science.282.5392.1298 .
  5. ↑ Eric Buffetaut , Mohamed Ouaja: A new specimen of Spinosaurus (Dinosauria, Theropoda) from the Lower Cretaceous of Tunisia, with remarks on the evolutionary history of the Spinosauridae. In: Bulletin de la Société Géologique de France. Vol. 173, No. 5, 2002, ISSN  0037-9409 , pp. 415-421, doi : 10.2113 / 173.5.415 .
  6. ↑ Thomas R. Holtz Jr., Ralph E. Molnar, Philip J. Currie : Basal Tetanurae. In: David B. Weishampel , Peter Dodson , Halszka Osmólska (eds.): The Dinosauria . 2nd edition. University of California Press, Berkeley CA et al. 2004, ISBN 0-520-24209-2 , pp. 71-110.