Crato Formation

The Crato Formation is a geologic formation of Early Cretaceous age in northeastern Brazil's Araripe Basin. It is an important Lagerstätte (undisturbed fossil accumulation) for palaeontologists. The strata were laid down mostly during the early Albian age, about 108 million years ago, in a shallow inland sea. At that time, the South Atlantic was opening up in a long narrow shallow sea.

The Crato Formation earns the designation of Lagerstätte due to an exceedingly well preserved and diverse fossil faunal assemblage. Some 25 species of fossil fishes are often found with stomach contents preserved, enabling paleontologists to study predator-prey relationships in this ecosystem. There are also fine examples of pterosaurs, reptiles and amphibians, invertebrates (particularly insects), and plants. Even dinosaurs are represented: a new maniraptor was described in 1996. The unusual taphonomy of the site resulted in limestone accretions that formed nodules around dead organisms, preserving even soft parts of their anatomy.