Microhadrosaurus Temporal range:
Late Cretaceous,
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | † Ornithischia |
Clade: | † Ornithopoda |
Family: | † Hadrosauridae |
Genus: | † Microhadrosaurus |
Species: | †M. nanshiungensis
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Binomial name | |
†Microhadrosaurus nanshiungensis
Dong, 1979
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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.
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). [1] Dong later estimated the length of the individual at 2.6 meters (8.5 feet). [2]
Dong regarded this genus as much like Edmontosaurus, albeit in tiny form. [1] 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. [3] The most recent review accepts Brett-Surman's position, and regards Microhadrosaurus as a dubious name. [4]
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. [4] 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.
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. [5] 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.