Dromaeosaurinae

From Wikipedia, the free encyclopedia
Dromaeosaurines
Temporal range: Early Cretaceous - Late Cretaceous, 130–65.5Ma
Possible Late Jurassic record
Artist's restoration of Utahraptor ostrommaysorum
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Theropoda
Family: Dromaeosauridae
Clade: Eudromaeosauria
Subfamily: Dromaeosaurinae
Matthew & Brown, 1922
Type species
Dromaeosaurus albertensis
Matthew & Brown, 1922
Genera

Dromaeosaurinae is a subfamily of Dromaeosauridae. Most dromaeosaurines lived in what is now the US and Canada, (Dromaeosaurus, Utahraptor), as well as Mongolia, (Achillobator, Adasaurus), and possibly Denmark, (Dromaeosauroides), as well. Isolated teeth that may belong to African dromaeosaurines have also been discovered in Ethiopia. These teeth date to the Tithonian stage, of the Late Jurassic Period.[1]

All North American and Asian dromaeosaurine dinosaurs from Late Cretaceous were generally small, no more than 1.8 metres long, in Dromaeosaurus and Adasaurus. However, among the dromaeosaurines were the largest dromaeosaurs ever; Achillobator was 6 metres long, and Utahraptor up to 7.

Classification and Phylogeny

Dromaeosaurines are distinguished from other dromaeosaurids in having stouter, box-shaped skulls, as opposed to the other subfamilies, which generally have narrower snouts. Also, dromaeosaurines are generally more heavily built, than the other members of their family, with thick, heavy-set legs, which were designed more for strength, rather than for speed.

Also, dromaeosaurines are distinguished from velociraptorines, in having a low DSDI ratio; i.e., their teeth have equal-sized serrations, on both the posterior and on the anterior edges. By contrast, velociraptorines often have larger serrations on the posterior side of the tooth, than the anterior, or no serrations on the anterior side at all.

Most dromaeosaurines lived during the Cretaceous period, from the Barremian to the Maastrichtian stages. However, as stated previously, at least one taxon must have lived much earlier, during the Jurassic Period.

The cladogram below follows a 2012 analysis by paleontologists Phil Senter, James I. Kirkland, Donald D. DeBlieux, Scott Madsen and Natalie Toth.[2]

Eudromaeosauria


Bambiraptor




Velociraptorinae

Adasaurus




Tsaagan



Velociraptor




Dromaeosaurinae

Deinonychus




Achillobator



Dromaeosaurus



Utahraptor



Yurgovuchia






References

  1. Goodwin, Clemens, Hutchinson, Wood, Zavada, Kemp, Duffin and Schaff (1999). "Mesozoic continental vertebrates with associated palynostratigraphic dates from the northwestern Ethiopian Plateau." Journal of Vertebrate Paleontology, 19(4): 728-741.
  2. Senter, P.; Kirkland, J. I.; Deblieux, D. D.; Madsen, S.; Toth, N. (2012). "New Dromaeosaurids (Dinosauria: Theropoda) from the Lower Cretaceous of Utah, and the Evolution of the Dromaeosaurid Tail". In Dodson, Peter. PLoS ONE 7 (5): e36790. doi:10.1371/journal.pone.0036790. PMC 3352940. PMID 22615813. 

External links

This article is issued from Wikipedia. The text is available under the Creative Commons Attribution/Share Alike; additional terms may apply for the media files.