Argyrosaurus

Argyrosaurus is an historically significant titanosaurian sauropod from the Late Cretaceous of Argentina. Named by the English naturalist Richard Lydekker, its moniker refers to Argentina itself, the land of silver. The holotype consists of a massive, robust left forelimb comprising the humerus, radius, ulna, and metacarpals. This limb indicates an exceptionally heavy and robust animal, though decades of taxonomy have seen many unrelated specimens assigned to the genus and later removed. Currently, Argyrosaurus is largely restricted to its definitive forelimb material, which makes total size estimates tentative. It was a quadrupedal plant-eater that relied on its pillar-like limbs to support a bulky body while foraging on the abundant vegetation of southern South America. Its historical description laid the foundation for more than a century of further titanosaur discoveries across Patagonia.

It was one of the earliest titanosaurs discovered and named in South America, described by Richard Lydekker in 1893.

Where and when

Argyrosaurus lived in the Late Cretaceous, from 72.1 to 66 million years ago (Maastrichtian age). Its remains come from Argentina, in the Lago Colhué Huapi Formation.

The numbers

Length 23 m (estimates run from 20 to 26 m). Mass about 26 t. Hip height about 4.5 m. That is 13.5 human-lengths, or 2.05 of a double-decker bus. These are estimates from fragmentary remains; fields marked estimated by the site are length, mass, first ma, last ma, hip height.

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