Rapetosaurus


Rapetosaurus (/rəˌptˈsɔːrəs/ rə-PAY-too-SOR-əs[1]) is a genus of titanosaurian sauropod dinosaur that lived in Madagascar from 70 to 66 million years ago, at the end of the Cretaceous Period. Only one species, Rapetosaurus krausei, has been identified.

Like other sauropods, Rapetosaurus was a quadrupedal herbivore; it is calculated to have reached lengths of 15 metres (49 ft).

Rapetosaurus was a fairly typical sauropod, with a short and slender tail, a very long neck and a huge, elephant-like body. Its head resembles the head of a diplodocid, with a long, narrow snout and nostrils on the top of its skull. It was a herbivore and its small, pencil-like teeth were good for ripping the leaves off trees but not for chewing.

It was fairly modest in size, for a titanosaur. The juvenile specimen measured 8 metres (26 ft) from head to tail, and "probably weighed about as much as an elephant". An adult would have been about twice as long (15 metres (49 ft) in length)[2] which is still less than half the length of its gigantic kin, like Argentinosaurus and Paralititan. In 2020 Molina-Perez and Larramendi estimated the size of the probable adult specimen (MAD 93-18), which is known from a femur, at 16.5 meters (54 ft) and 10.3 tonnes (11.35 short tons).[3]

The discovery of Rapetosaurus, known by the single species Rapetosaurus krausei marked the first time a titanosaur had been recovered with an almost perfectly intact skeleton, complete with skull. It has helped to clarify some difficult, century-old classification issues, among this large group of sauropod dinosaurs and provides a good baseline for the reconstruction of other titanosaurs that are known only from partial fossilized remains.

The discovery was published in 2001 by Kristina Curry Rogers and Catherine A. Forster in the scientific journal Nature. The nearly-complete skeleton is that of a juvenile and partial remains from three other individuals were also recovered.


Rapetosaurus restoration
Skull cast, Royal Ontario Museum, Canada.
Size comparison of a juvenile specimen
Field Museum mount in side view
Mounted Majungasaurus and Rapetosaurus
Restoration of two Majungasaurus chasing Rapetosaurus