Microhadrosaurus
{{Short description|Extinct genus of dinosaurs}}
{{Speciesbox
| fossil_range = Late Cretaceous, {{fossil range|66.7|66}}
| taxon = Microhadrosaurus nanshiungensis
| authority = Dong, 1979
}}
Microhadrosaurus (meaning "small sturdy lizard" in Greek) is a genus of hadrosaurid dinosaur from the Campanian or Maastrichtian-age Upper Cretaceous Yuanpu Formation (also known as the Nanxiong Formation) of Guangdong, China. Although its name identifies it as a small hadrosaur, it is based on juvenile remains, and the size of the adult hadrosaur is unknown.
Description
Dong Zhiming named this genus for IVPP V4732, a partial lower jaw from a juvenile hadrosaur. This partial bone, with 18 columns of stacked teeth in a typical hadrosaur tooth battery, measures 37 centimeters long (15 inches).{{cite book |author=Dong Zhiming |author-link=Dong Zhiming |title=Mesozoic and Cenozoic Red Beds of South China |year=1979 |publisher=Science Press |location=Nanxiong, China |language=zh |pages=342–350 |chapter=The Cretaceous dinosaur fossils in southern China }} Dong later estimated the length of the individual at 2.6 meters (8.5 feet).{{cite book |author=Dong Zhiming |author-link=Dong Zhiming |title=Dinosaurs from China |year=1987 |publisher=China Ocean Press |location=Beijing |isbn=0-565-01073-5 |pages=1–114 }}
History
Dong regarded this genus as much like Edmontosaurus, albeit in tiny form. However, Michael K. Brett-Surman, a hadrosaur specialist, regarded the material as showing no characteristics that would allow it to be differentiated from other duckbills.{{cite book |last=Brett-Surman |first=Michael K. |title=A revision of the Hadrosauridae (Reptilia:Ornithischia) and their evolution during the Campanian and Maastrichtian. Ph.D. dissertation |year=1989 |publisher=Graduate School of Arts and Sciences of The George Washington University |location=Washington, D.C. |pages=1–272}} The most recent review accepts Brett-Surman's position, and regards Microhadrosaurus as a dubious name.{{cite book |last=Horner |first=John R. |author-link=Jack Horner (paleontologist) |author2=Weishampel, David B. |author3= Forster, Catherine A |editor=Weishampel, David B. |editor2=Dodson, Peter |editor3=Osmólska, Halszka |title=The Dinosauria |edition=2nd |year= 2004|publisher=University of California Press |location=Berkeley |isbn=0-520-24209-2 |pages=438–463 |chapter=Hadrosauridae }}
Paleobiology
As a hadrosaurid, Microhadrosaurus would have been a bipedal/quadrupedal herbivore, eating plants with a sophisticated skull that permitted a grinding motion analogous to chewing, and was furnished with hundreds of continually-replaced teeth. Because it is only known from a partial jaw from a juvenile, little more than general information can be drawn from it at this point.
Paleoecology
=Fauna and habitat=
The Nanxiong Formation consists of a 2000-meter sequence of red sandstones and clays which has yielded dinosaur fossils, dinosaur footprints and abundant egg shells.{{cite web|title=Nanxiong Formation|url=http://www.dinodata.org/index.php/dinosaursa/fs/2845-nanxiong-formation-guandong-china|access-date=29 September 2013|url-status=dead|archive-url=https://web.archive.org/web/20140810153818/http://www.dinodata.org/index.php/dinosaursa/fs/2845-nanxiong-formation-guandong-china|archive-date=10 August 2014}} Microhadrosaurus shared its paleoenvironment with the sauropod Gannansaurus, the therizinosauroid Nanshiungosaurus, the tyrannosaurid Qianzhousaurus and the oviraptorids Banji, Jiangxisaurus, Corythoraptor, Ganzhousaurus, Huanansaurus, Nankangia and Tongtianlong.
See also
{{Portal|Dinosaurs}}
References
{{Reflist}}
{{Ornithopoda|D.}}
{{Taxonbar|from=Q988563}}
Category:Maastrichtian dinosaurs
Category:Taxa named by Dong Zhiming