| Microhadrosaurus Temporal range: Late Cretaceous,
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|---|---|
Scientific classification 
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| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| 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 bulky lizard" in Greek) is a genus of hadrosaurid dinosaur from the Late Cretaceous (Campanian or Maastrichtian) Nanxiong Formation of Guangdong, China. Although its name identifies it as a small hadrosaurid, it is based on juvenile remains, and the adult size 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.
