Sauroposeidon

Sauroposeidon was a colossal sauropod that inhabited coastal river plains across what is now the south-central United States during the Early Cretaceous. It was first described from a series of enormous neck vertebrae discovered in Oklahoma, initially mistaken for giant petrified tree trunks. These vertebrae were extraordinarily elongated and hollowed out with internal air cells supported by paper-thin bone struts to minimise weight. While initially classified as a brachiosaurid, newer phylogenetic analyses often place it among basal somphospondyls. With its exceptionally long neck, Sauroposeidon could likely browse foliage up to seventeen or eighteen metres off the ground, towering over its contemporary ecosystem. Body length estimates reach up to thirty-four metres, making it one of the tallest and most massive land creatures ever known from North America.

4 metres long and permeated by delicate, honeycomb-like air cavities.

Where and when

Sauroposeidon lived in the Early Cretaceous, from 113 to 100.5 million years ago (Aptian-Albian age). Its remains come from United States, in the Antlers Formation.

The numbers

Length 31 m (estimates run from 27 to 34 m). Mass about 47 t. Hip height about 6 m. That is 17.9 human-lengths, or 2.72 of a double-decker bus. These are estimates from fragmentary remains; fields marked estimated by the site are length, mass, hip height.

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