The titanosaurids (or titanosaurs, the members of the groups Titanosauria and/or Titanosauroidea) were the major group—and truly the only dominant group—of sauropods that lived during the Cretaceous period. They represent a great mystery for paleontologists, too. In fact, only recently have skulls or relatively complete skeletons (such as the Rapetosaurus) of any of the roughly 50 species of titanosaurs been discovered.

These dinosaurs had small, slender, pencil-like teeth, similar to the diplodocids. Because of this, until recently, paleontologists put the diplodocids and titanosaurids into the same family—even though parts of both dinosaurs’ skulls were very different. In general, the titanosaurs had small, elongated heads, large nostrils, and crests formed from the nostril bones. Most of the titanosaurs lived in the southern continents of Gondwana, especially the southern parts of today’s South America and India. Bones of these dinosaurs have also been found in many other places, including Brazil, Malawi, Spain, Madagascar, Laos, Egypt, Romania, France, and the southern United States.