Describer

Brown& Schlaikjer, 1943

Time

Cretaceous Late Campanian Maastrichtian

Classification

Ornithischia Genasauria Cerapoda Marginocephalia Pachycephalosauria Pachycephalosauridae

Diet

Herbivore

Fossilsite

US

Typespecies

Pachycephalosaurus wyomingensis

Length

4,6 meter

Info

Genus - Skull

Pachycephalosaurus (Brown& Schlaikjer, 1943) = Tylosteus (Leidy, 1872)

Pachycephalosaurus > Pachycephalosaurus wyomingensis (Gilmore, 1931) >> Troodon wyomingensis (Gilmore, 1931) >>> Tylosteus ornatus (Leidy, 1872), Pachycephalosaurus grangeri (Brown & Schlaikjer, 1943) Pachycephalosaurus reinheimeri (Brown & Schlaikjer, 1943)

Pachycephalosaurus (Brown& Schlaikjer, 1943) > Pachycephalosaurus wyomingensis (Gilmore, 1931) > Dracorex hogwartsia [Juvenile] (Bakker, Sullivan, Porter, Larson & Saulsbury, 2006) > Stygimoloch spinifer [subadult] Galton & Sues, 1983 >> Stenotholus kohleri (Giffin, Gabriel & Johnson, 1987)

\\\"Thick- headed lizard\\\" The largest of the bone-headed dinosaurs, Pachycephalosaurus is known from only one skull and a few immensely thick skull roofs up to 25cm (10in) thick. The teeth were tiny. Because remains other than those of skulls are unknown, the body proportions and size had to be estimated from the known skeletons of other pachycephalosaurs, especially Stegoceras.

Pachycephalosaurus type species was originally Pachycephalosaurus grangeri, but this was synonymized with earlier-named Troodon wyomingensis and thus became Pachycephalosaurus wyomingensis.