Janenschia

Janenschia is a heavily built sauropod that lived during the Late Jurassic in what is now Tanzania. Named in honour of Werner Janensch, the palaeontologist who directed the famous German excavations at Tendaguru Hill, its remains include limb bones and caudal vertebrae. The type specimen, a robust hind limb, initially led researchers to place it in the genus Gigantosaurus and later Tornieria before receiving its own genus in 1991. For several decades, Janenschia was celebrated as the earliest known representative of the titanosaurs, though recent analyses tend to place it just outside Titanosauria as a basal titanosauriform or eusauropod. Janenschia was a stocky quadruped, supporting its considerable weight on pillar-like legs while grazing and browsing on Jurassic foliage. It represents one of many distinct sauropod body plans flourishing together in eastern Gondwana.

It was long considered the oldest known titanosaur, though modern cladistic studies classify it more broadly near basal Titanosauriformes.

Where and when

Janenschia lived in the Late Jurassic, from 152.1 to 145 million years ago (Kimmeridgian-Tithonian age). Its remains come from Tanzania, in the Tendaguru Formation.

The numbers

Length 18 m (estimates run from 16 to 20 m). Mass about 17 t. Hip height about 4 m. That is 10.6 human-lengths, or 1.61 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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