Monoclonius

Monoclonius is the doubtful name of a ceratopsid dinosaur. It was a herbivore (plant-eater) It lived in North America during the Upper Cretaceous, about 76 to 73 million years ago.

Monoclonius
Artist's impression
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Superorder:	Dinosauria
Order:	Ornithischia
Suborder:	Marginocephalia
Infraorder:	Ceratopsia
Family:	Ceratopsidae
Genus:	Monoclonius Cope, 1876
Species
M. crassus Cope, 1876 (type)

The "Monoclonius nasicornus" skeleton (material now more usually classified in Centrosaurus or Styracosaurus).

Monoclonius was named by Edward Drinker Cope in 1876, soon after the first fossil specimen had been found in Montana. The specimen was a near complete skeleton with only the feet missing. It included skull material and the base of the nasal horn. Its name means "single stem" and refers to its teeth, which have a single root.

Monoclonius is now regarded as a nominem dubium. It seems to be a juvenile stage of Centrosaurus.^[1]

References

1. Ryan, M.J. (2006). "The status of the problematic taxon Monoclonius (Ornithischia: Ceratopsidae) and the recognition of adult-sized dinosaur taxa". Geological Society of America Abstracts with Programs. 38 (4): 62.