Homalocephale

Homalocephale was a small bipedal ornithischian dinosaur discovered in the Nemegt Formation of the Gobi Desert in Mongolia. 8 metres in length, weighing around forty kilograms. Unlike many of its close relatives which possessed high, domed skulls, Homalocephale had a flat, wedge-shaped skull roof decorated with small bony nodules. Some palaeontologists have suggested it represents a juvenile form of Prenocephale, although differences in pelvic structure have kept its status debated. It had an unusually broad pelvis and a stiffened tail reinforced with interlocking ossified tendons. Homalocephale fed on low-growing shrubs, seeds, and leafy plants in semi-arid river valleys.

Its skull possessed a completely flat, thickened roof rather than the rounded dome seen in Pachycephalosaurus.

Where and when

Homalocephale lived in the Late Cretaceous, from 71 to 69 million years ago (Campanian-Maastrichtian age). Its remains come from Mongolia, in the Nemegt Formation.

The numbers

Length 1.7 m (estimates run from 1.5 to 1.8 m). Mass about 40 kg. Hip height about 0.6 m. That is 1 human-lengths, or 0.15 of a double-decker bus. These are estimates from near-complete skeleton; fields marked estimated by the site are length, mass, first ma, last ma, hip height.

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