Elaphrosaurus

Unikonta

Elaphrosaurus
Temporal range: Late Jurassic, 154–150 Ma
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Holotype skeleton mounted (skull, hands and other elements speculative), Museum für Naturkunde Berlin
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Superorder: Dinosauria
Order: Saurischia
Suborder: Theropoda
Node: Neotheropoda
Infraorder: †Ceratosauria
Genus: †Elaphrosaurus
Janensch, 1920
Species: †E. bambergi
Binomial name
Elaphrosaurus bambergi
Janensch, 1920

Elaphrosaurus (meaning "lightweight lizard") is a genus of theropod dinosaur from the Kimmeridgian stage of the Late Jurassic of Tanzania. Elaphrosaurus was probably a ceratosaur about 6 meters (20 ft) long. Suggestions that it is a late surviving coelophysoid have been entertained but are generally dismissed. It was first described as a coelurid.[1] At the time, Coeluridae was a wastebasket taxon for small theropods. Later, it was thought that Elaphrosaurus was related to ornithomimids,[2] but this has also lost favor in preference to a ceratosaurian identity.[3]

A skeleton was found in the Tendaguru Beds of Tanzania, which also yielded Giraffatitan, Allosaurus, and Kentrosaurus. A related animal, perhaps the same genus, was found in the Morrison Formation.[4] Few theropod skeletons have been found, most discoveries being fragments. Material from the Early Cretaceous of Niger was named E. gautieri in 1960, but it has since been renamed Spinostropheus by Sereno et al. (2004). What is known about Elaphrosaurus mostly comes from a single nearly complete skeleton. No skull has been found.

It was long and slender, with a long neck. It was about 6.2 meters (20 ft) long, 1.46 meters (4.79 ft) tall at the hip, and weighed about 210 kilograms (460 lb).[4] The tibia (shin bone) of Elaphrosaurus was considerably longer than its femur (thigh bone), which indicates that it could probably run very fast.[5] It is also possibly present in stratigraphic zones 2-4 of the Morrison Formation.[6]

References

  1. ^ Janensch, Werner (1920). "Über Elaphrosaurus bambergi und die Megalosaurier aus den Tendaguru–Schichten Deutsch–Ostafrikas" (in German). Sitzungsberichte der Gessellschaft Naturforschender Freunde zu Berlin 1920: 225–235. 
  2. ^ Russell, Dale A. (1972). "Ostrich dinosaurs from the Late Cretaceous of western Canada". Canadian Journal of Earth Sciences 9: 375–402. 
  3. ^ Tykoski, R.S.; Rowe, T. (2004). "Ceratosauria". In Weishampel, D.B.; Dodson, P.; Osmólska, H.. The Dinosauria: Second Edition. University of California Press. pp. 47–70. ISBN 0520242092. 
  4. ^ a b Paul, Gregory S. (1988). "Genus Elaphrosaurus". Predatory Dinosaurs of the World. New York: Simon & Schuster. pp. 265–266. ISBN 0-671-61946-2. 
  5. ^ Foster, John (2007). Jurassic West: The Dinosaurs of the Morrison Formation and Their World. Indiana University Press. p. 182. ISBN 978-0-253-34870-8. 
  6. ^ Foster, J. (2007). "Appendix." Jurassic West: The Dinosaurs of the Morrison Formation and Their World. Indiana University Press. pp. 327-329.