A relatively complete skeleton of a long-necked, long-tailed plant-eater excavated from a rocky cliff above a Tanzanian river is providing insight into the early evolution of a dinosaur group that later included Earth's largest-ever land animals.

Scientists on Wednesday announced the discovery of fossils of a dinosaur called Mnyamawamtuka moyowamkia, which measured roughly 26 feet (8 meters) long, weighed about 1 ton, lived between 110 and 100 million years ago and was an early and comparatively small member of the group called titanosaurs.

Titanosaurs, which walked on four pillar-like legs, first appeared earlier in the Cretaceous Period, perhaps 125 million years ago. By the time an asteroid impact caused a mass extinction that doomed the dinosaurs nearly 66 million years ago, titanosaurs had achieved staggering dimensions. For example, Argentina's Patagotitan was about 120 feet (37 meters) long and weighed 70 tons.