[D] Triceratops [Su] [sG]
Cretaceous Late Maastrichtian
Ornithischia Genasauria Cerapoda Marginocephalia Ceratopia Neoceratopia Ceratopidae Chasmosaurinae
Triceratops (Marsh, 1889) = Sterrholophus flabellatus (Marsh, 1891)
Triceratops > Triceratops horridus (Marsh, 1889) = Ceratops horridus (Marsh, 1889) >> Triceratops alticornis (Marsh, 1887) Triceratops flabellatus (Marsh, 1889), Triceratops prorsus (Marsh, 1890), Triceratops serratus (Marsh, 1890), Triceratops elatus (Marsh, 1891) Triceratops calicornis (Marsh, 1898), Triceratops obtusus (Marsh, 1898), Triceratops hatcheri (Lull, 1905), Triceratops brevicornus (Hatcher, 1905), Triceratops eurycephalus (Schlaikjer, 1935), Triceratops albertensis (Sternberg, 1949)
\\\\\\\"Three-horned face\\\\\\\"proved to be the largest known ceratopsid - heavy as an elephant, with a massive body, and a head as long as the height of a human. A broad, bony frill stuck out from the back of its deep beaked skull, and two long, hollow based brow horns jutted above its eyes. The nose horn was short.
Triceratops is placed within the chasmosaurine subfamily, most of whose members have long neck frills. One of the last and most numerous of all horned dinosaurs.A hollow high in the skull functioned as a shockabsorber, cushioning the brain. Evidence of old, healded wounds in the cheek and frill bones of some Triceratops skulls suggest injuries caused by horns, when rival mates fiercely fought each other. Triceratops skull is more than one-third the length of the entire animal.
Other features include the short neck, covered by the neck frill, the short tail, and powerful, heavily built limbs. Triceratops walked on its toes. The systematics of the genus as presented by Forster in Journal of Vertebrate Paleontology 16 (2): is:
Triceratops horridus = Triceratops flabellatus = Triceratops serratus = Triceratops elatus = Triceratops calicornis = Triceratops obtusus Triceratops prorsus = Triceratops brevicornus All other species are nomina dubia , with the exception of Triceratops hatcheri , which is retained as the type species of the separate genus Diceratops.
The idea that Triceratops horridus and Triceratops prorsus might be sexual dimorphs of a single species is considered and rejected, even though the species are sympatric, because many more specimens referable to Triceratops horridus than to Triceratops prorsus have been discovered.