Santanaraptor

Santanaraptor
Temporal range: Early Cretaceous, 108Ma
Reconstructed skeleton
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Superorder: Dinosauria
Order: Saurischia
Suborder: Theropoda
Superfamily: Tyrannosauroidea
Genus: Santanaraptor
Kellner, 1999
Species
  • S. placidus Kellner, 1999 (type)

Santanaraptor (meaning "Santana Formation thief") is a genus of theropod dinosaur that lived in South America during the Albian[1] or Aptian[2] stage of the Early Cretaceous, about 115-110 million years ago. It is known from a partial juvenile specimen recovered with fragments of mineralized soft tissue, including, muscle and skin tissue, but unfortunately not trace of the skins external covering, which was unearthed in 1996 from the Romualdo Formation (Santana Group) in the Ceará State, northeastern Brazil.[3] While primarily known from hindquarter elements, the individual represented by the fossil may have reached 1.25 metres (4.1 ft) in length.[1] The fossil consists of bones from the pelvis, hindlimbs, and tail. These provide little information on its overall appearance. However, it was definitely a coelurosaur, and a few of its details suggest that it might be an ancestor of the tyrannosauroids. It is presumed to be similar to Dilong and Guanlong and that it had long arms, three fingered hands, and slim hindlimbs.[3] Santanaraptor is thought by some paleontologists to be the first tyrannosauroid known from Gondwana,[2][4] but it may be a more basal coelurosaur.[1]

Classification

The holotype (MN 4802-V) consists of 3 caudal vertebrae with chevrons, ischia, femora, tibia, fibula, pes, and soft tissue. The fossilized tissue includes a thin epidermis, muscle fibers, and possibly blood vessels.[1]

The type species is S. placidus, first described by Kellner in 1999.[5] The species epithet refers to Placido Cidade Nuvens , who founded the Museu de Paleontologia da Universidade Regional do Cariri .[1]

Santanaraptor was originally thought to be a maniraptoran theropod when it was first discovered. However, it is now thought to be a basal coelurosaur based on several features present on the femur. Santanaraptor may have been closely related to Ornitholestes, an earlier coelurosaur of the Late Jurassic, based on similarities in the ischium, a bone of the pelvis.[1]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 "Santanaraptor placidus [sG] [T]". DinoData. Retrieved 2008-08-13.
  2. 2.0 2.1 Holtz, Thomas R. Jr. (2004). "Tyrannosauroidea". The Dinosauria (Second ed.). University of California Press.
  3. 3.0 3.1 Benton, Michael J. (2012). Prehistoric Life. Edinburgh, Scotland: Dorling Kindersley. p. 321. ISBN 978-0-7566-9910-9.
  4. Holtz, Thomas R. Jr. (2011) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages, Winter 2010 Appendix.
  5. Kellner, A. W. A. (1999). "Short Note on a new dinosaur (Theropoda, Coelurosauria) from the Santana Formation (Romualdo Member, Albian), northeastern Brazil". Boletim do Museu Nacional (Serie Geologia) 49: 18.

External links