Temporal range: Upper Triassic (Carnian)
fossil range: 231.4–228.91 mya
|Mounted cast of skeleton, Senckenberg|
Description[change | change source]
Herrerasaurus was a lightly built bipedal carnivore with a long tail and a relatively small head. Its length is estimated at 3 to 6 meters (10 to 20 ft), and its hip height at more than 1.1 meters (3.3 ft). It may have weighed around 210–350 kilograms (463–772 lb).
The tail, partially stiffened by overlapping vertebral projections, balanced the body and was also an adaptation for speed.
Palaeoenvironment[change | change source]
The paleoenvironment of the Ischigualasto Formation (where it was found) was a volcanically active floodplain covered by forests with seasonal rainfall. The climate was moist and warm, with seasonal variations. Vegetation consisted of ferns, horsetails, and giant conifers. These plants formed lowland forests along the banks of rivers. Herrerasaurus was the most common of the carnivores of the Ischigualasto Formation.
Herrerasaurus lived in these jungles alongside a smaller dinosaur, the one metre long Eoraptor, as well as Saurosuchus, a huge quadrupedal Archosaur. There were also a number of therapsid and reptilian herbivores. The dinosaurs had not yet taken control of the land environments as they did later.
References[change | change source]
- Alcober, Oscar A.; Martinez, Ricardo N. (2010). "A new herrerasaurid (Dinosauria, Saurischia) from the Upper Triassic Ischigualasto Formation of northwestern Argentina". ZooKeys (63): 55–81. doi:10.3897/zookeys.63.550. PMC 3088398. PMID 21594020.
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- Sereno P.C. and Novas F.E. 1992. The complete skull and skeleton of an early dinosaur. Science 258 (5085): 1137–1140.
- Paul G.S. 1988 Predatory dinosaurs of the world (1989). Predatory Dinosaurs of the World: A Complete Illustrated Guide. New York: Simon and Schuster. pp. 248–250. ISBN 0-671-68733-6.
- Langer, Max C. 2004. Basal Saurischia. In Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds) The Dinosauria. 2nd ed, Berkeley: University of California Press, pp. 25–46. ISBN 0-520-24209-2
- Tucker, Maurice E.; Benton, Michael J. (1982). "Triassic environments, climates and reptile evolution". Palaeogeography, Palaeoclimatology, Palaeoecology. 40 (4): 361–379. doi:10.1016/0031-0182(82)90034-7.
- Columbi, Carina E. 2008. Stable isotope analysis of fossil plants from the Upper Triassic Ischigualasto Formation in the northwest of Argentina. Houston, Texas: The Geological Society of America. Archived from the original on 2012-01-11. Retrieved 2014-01-01.
- Sill, W D; Sill, W. D. (1974). "The anatomy of Saurosuchus galilei and the relationships of the rauisuchid thecodonts". Bulletin of the Museum of Comparative Zoology at Harvard College. 146: 317–362. ISSN 0027-4100.