TITANOSAURID (SAUROPODA) OSTEODERMS FROM THE LATE CRETACEOUS OF MADAGASCAR

In 1896 Charles Deperet described a fauna of dinosaurs from the Upper Cretaceous (?Campanian) Maevarano Formation from the Mahajanga Basin o f northwest Madagascar. Among the dinosaurs was a titanosaurid sauropo d that he named Titanosaurus madagascariensis. He attributed to the ti tanosaurid a large, thick circular osteoderm. His referral of an osteo derm to a sauropod was widely doubted until 1980 when Bonaparte and Po well described Saltasaurus loricatus, an armored titanosaurid from Arg entina. Since then titanosaurid osteoderms have been recognized from S pain, France and Malawi. In 1996, we collected three isolated and eigh t associated osteoderms from the Maevarano Formation, confirming Deper et's prescient observation. They range in length from 3 cm to 17 cm, a nd in thickness up to 6.5 cm. Ar least one of the two titanosaurids we now recognize from Madagascar was covered with a sparse armor, and th at the skin was in places nearly 7 cm thick.