Razanandrongobe head close-up

Razanandrongobe , the name meaning; as ''ancestor of the large lizard" in the Malagasy language, is a genus of carnivorous, sebecosuchian crocodyliforms, from the Middle Jurassic of Madagascar.

The Species based on MSNM V5770, a fragment, the main tooth-bearing bone of the upper jaw, and several isolated teeth have also been assigned to it. The remains come from the middle jurassic age of Mahajanga.
Razana scale

Estimated size of Razanandrongobe sakalavae.Picture: Natural History Museum (Milan)

The jaw fragment and teeth are very similar to the representative bones of theropod dinosaurs and some types of crocodylomorphs, and the authors refrained from assigning the genus to either group until recently. The paleontologists interpreted the stout teeth as having been used for crushing bones, and their denticles are remarkably large, even larger than those of Tyrannosaurus! The Remains described in 2017 have given further insight, revealing it to be the oldest known notosuchian species.

Razanandrongobe illustration

Razanandrongobe feeding on a Sauropod carcass


Razanandrongobe has a highly specialized skull, with a robust and rounded, U-shaped snout that is taller than it is wide, oreinirostrals, like the Dakosaurus. Like the snout, the lower jaw is also tall and robust.

Image 5014 2-Razanandrongobe-sakalavae

The fossil

Most noticably, the tip of the lower jaw that is devoid of teeth. The front of the jaw would have been fused; on the inside of the bone, there is a scar running along the rear 20% of the fused portion, representing the attachment of the splenial bone. The teeth that the animal had are highly unusual; they bear large serrations on both the front and rear edges, which are proportionally even larger than those of dinosaurs such as Tyrannosaurus. They are also thick, non-constricted, and slightly recurved, and are U-shaped in cross section. The smallest teeth are globe-shaped. None of the teeth are like the canine teeth of mammals.


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