Spiclypeus

Spiclypeus was an impressive chasmosaurine ceratopsian that roamed the floodplain forests of Montana roughly seventy-six million years ago. Measuring between five and six metres long and weighing as much as three tonnes, it was a heavy-set quadruped roughly the size of an adult Asian elephant. Its name, meaning 'spiked shield', refers to its striking neck frill, which featured an unusual arrangement of curling bone spikes: the central pair hooked downwards over the frill surface, while the outer spikes pointed upwards and outwards. The single known skeleton, affectionately named 'Judith', represents an elderly individual whose bones tell a dramatic story of survival. Pathological examinations revealed that Judith lived for years with severe chronic arthritis and a debilitating bone infection in its left shoulder and upper arm, illustrating the tough physical existence of Late Cretaceous horned herbivores.

The type specimen, nicknamed 'Judith', suffered from severe bone infections and arthritis in its left arm.

Where and when

Spiclypeus lived in the Late Cretaceous, from 76.2 to 75.2 million years ago (Campanian age). Its remains come from United States, in the Judith River Formation.

The numbers

Length 5.5 m (estimates run from 5 to 6 m). Mass about 2.4 t. Hip height about 1.9 m. That is 3.2 human-lengths, or 0.49 of a double-decker bus. These are estimates from partial skeleton; fields marked estimated by the site are length, mass, hip height.

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