The Janenschia (named after Werner Janensch) was a gigantic, long-necked sauropod that lived during the Upper Jurassic Tendaguru Formation of Tanzania, Africa, approximately 155 million years ago. It lived in an incredibly mild climate, during a time when there was no polar ice and sea levels were higher than they are today. Despite the lack of fossil evidence, it’s probable that Janenschia had armored plates like other titanosaurids.

Key Facts

Janenschia pronunciationJa·nen·schi·a
What does Janenschia mean?Named after Werner Janensch
Dinosaur typeSauropod
On the menuHerbivorous
Length98 ft (30 m)
Height80 ft (25 m)
Weight33 tonnes (about 100,000 lbs)
Life expectancyUnknown
Legs used to get aroundQuadrupedal
Estimated top speedUnknown
When they livedUpper Jurassic period approximately 155 million years ago
Where they have been found?Tanzania

When & Where

Janenschia was named after the German paleontologist, Werner Janensch, who studied the fossils of this dinosaur and other sauropods from Tanzania. The first fossils were discovered in Lindi, Tanzania in 1907. The bones included a femur that measured about 4 1/2 feet (1.38 meters) in length, three clawed hindlimbs, two forelimbs, and back and tail vertebrae. 

Size & Weight

Based on the limited fossil evidence that is available, it is estimated that Janenschia was a large sauropod, with a length of up to 30 meters (98 feet) and a weight of up to 50-60 tons. Its height is not well-known, but it may have been up to 4-5 meters (13-16 feet) tall at the shoulder. 

Mobility & Diet

It is unlikely that the Janenschia dinosaur was bipedal. Most sauropod dinosaurs, including Janenschia, were quadrupeds, meaning that they walked on four legs. Sauropods had long necks and tails, and their bodies were supported by four sturdy legs. This body plan allowed them to move quickly and efficiently on land, and it is thought to have been well-suited to their herbivorous lifestyle.

The large size and unique body plan of sauropods like Janenschia would have made bipedalism difficult or impossible. Bipedalism is a trait that evolved in some dinosaurs as a way to increase speed and agility, but it would have been less advantageous for a large, heavy animal like Janenschia. Instead, its four legs would have provided the necessary support and stability to allow it to move efficiently on land.

Much about this dinosaur remains a mystery, and further research is needed to learn more about its behavior and ecology.

Interesting Points

  • It had a small head, a long neck, and a long tail, which it may have used for balance as it moved. Its forelimbs were shorter than its hind limbs, giving it a distinctive posture.
  • Janenschia was one of the first sauropod dinosaurs to evolve, appearing during the early Jurassic period, approximately 190 million years ago.
  • Despite its discovery over a century ago, much about this dinosaur remains a mystery, and further research is needed to learn more about its behavior and ecology.

Featured Image Credit: National HIstory Museum