Triceratops ("three-horned face") was a ceratopsid herbivorous dinosaur species from the Latest Cretaceous time of North America. It was about 9 m (30 ft) long, and almost certainly weighed approximately 5,400 kg (12,000 lb).

Discoveries and species

Triceratops was exposed by John Bell Hatcher in 1888. Its statement as a legitimate dinosaur came when a whole skull was found. It was named by Othniel Charles Marsh in 1889. Two years earlier, however, he misidentified the Triceratops as a type of bison. The strong natural world of the animal's skull has ensured that many examples have been preserved as fossils, allowing variations between species and persons to be studied.

Known species of Triceratops include T. prorsus and T. horridus. Diceratops was formerly supposed to be a species of Triceratops as well, but is currently documented as a separate genus and species.

Triceratops species:

T. horridus Marsh, 1889 (type species)
T. prorsus Marsh, 1890

Nomina dubia:

T. albertensis Sternberg, 1949
T. alticornis Marsh, 1887 (originally 'Bison')
T. eurycephalus Schlaikjer, 1935
T. galeus Marsh, 1889
T. ingens Lull, 1915
T. maximus Brown, 1933
T. sulcatus Marsh, 1890

Misassignments:

T. brevicornis Hatcher, 1905 (=T. prorsus)
T. calicornus Marsh, 1898 (=T. horridus)
T. elatus Marsh, 1891 (=T. horridus)
T. flabellatus Marsh, 1889 (=T. horridus)

T. hatcheri Lull, 1907 (=Diceratops hatcheri)
T. mortuarius Cope, 1874 (also nomen dubium; originally Polyonax; =Polyonax mortuarius)
T. obtusus Marsh, 1898 (=T. horridus)
T. serratus Marsh, 1890 (=T. horridus)
T. sylvestris Cope, 1872 (nomen dubium; originally Agathaumas; =Agathaumas sylvestris)