Eshanosaurus

Taxobox|
name = "Eshanosaurus"
fossil_range = Early Jurassic
status = fossil
regnum = Animalia
phylum = Chordata
classis = Sauropsida
superordo = Dinosauria
ordo = Saurischia
subordo = ?Theropoda
familia = ?Therizinosauridae
genus = "Eshanosaurus"
species = "E. deguchiianus"
binomial = "Eshanosaurus deguchiianus"
binomial_authority = Xu, "et al.", 2001

"Eshanosaurus" is the name given to a genus of dinosaur from the Early Jurassic. It is known only from a partial lower jaw-bone. The fossil was found in China. It may be the earliest known Coelurosaur.

The type species, "Eshanosaurus deguchiianus", was described by Xu, Zhao, and Clark in 2001. The authors here place "Eshanosaurus" in the therizinosaur family on the basis of three distinct synapomorphies. That makes it the earliest known Coelurosaur, and an advanced maniraptor living long before "Archaeopteryx".

Mistakes have been made in Paleontology in the past when fossil teeth and jaws have been assigned to advanced dinosaur groups and later reassigned to more primitive reptiles (see "Lisboasaurus"). Especially troublesome for "Eshanosaurus" is that it was found below numerous fossils of "Lufengosaurus", a prosauropod which can very closely resemble a therizinosaur. The authors are aware of this, and exclude this possibility as rigorously as they can.

References

* http://www.users.qwest.net/~jstweet1/dinosauromorpha.htm
* http://www.dinosauria.com/dml/names/dinoe.htm

A NEW THERIZINOSAUR FROM THE LOWER JURASSIC LOWER LUFENG FORMATION OFYUNNAN, CHINAXING XU, XIJIN ZHAO, and JAMES M. CLARKJournal of Vertebrate Paleontology 21(3):477–483, September 2001q 2001 by the Society of Vertebrate Paleontology