Rahonavis - Discovery and Species

Discovery and Species

The fossilized remains of Rahonavis were first recovered in 1995 by a joint expedition of SUNY and the University of Antananarivo, near the village of Berivotra. Most geological formations in this area are covered in dense grass, making identification of fossils difficult. However, when a portion of hillside was exposed by fire, the remains of a giant titanosaur were revealed. It was during the excavation of this find that paleontologists discovered the bones of Rahonavis among the bones of the much larger dinosaur. Rahonavis is known from this single specimen, consisting of the hind limbs, trunk, portions of the tail (all of which were found articulated), as well as portions of the wing and shoulder bones. Rahonavis was one-fifth larger than the closely related Archaeopteryx, about the size of a modern raven.

The lack of well-documented relatives of this species nonwithstanding, a single thoracic vertebra (NMC 50852) most similar to those of R. ostromi was found in mid-Cretaceous sediments (Albian/Cenomanian, c. 100 to 99 million years ago) of the Kem Kem region, Morocco. Lacking the pleurocoels found in Rahonavis and having a larger neural canal, it appears to belong to a different genus. Although former character can vary in species of the same genus, in individual vertebrae of the same animal, and ontogenetically, the distance in space and time suggests that whatever this specimen may be, it does not belong into Rahonavis.