The Crato Formation in the Araripe Basin of northeast Brazil, is a lagerstätte, or undisturbed fossil accumulation, where rich deposits of fossils were laid down during the Aptian phase of early Cretaceous times, ca 117 Ma. At that time, the South Atlantic was opening up in a long narrow shallow sea. Lagerstätten (German, singular: Lagerstätte, literally: place(s) of storage or resting place(s)) are sedimentary deposits that exhibit extraordinary fossil richness or completeness. ... The Early Cretaceous - also called the Lower Cretaceous by geologists, is the earlier of the two major divisions of the Cretaceous period. ... The Cretaceous period is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic period (about 135 mya) to the beginning of the Paleocene epoch of the Tertiary period (65 mya). ...

The Crato Formation is the product of a single phase in the Santana Formation, where complicated sequence of sediment strata reflect changeable conditions in the opening sea. The Santana Formation is a Lagerstätte in northeastern Brazils Araripe Basin where the states of Pernambuco, Piaui and Ceara come together. ... For discussion regarding the term strata as used in geology, see stratum. ...

Fish fossils in the area were noted in 1823. When they were first methodically published, in 1993, the Crato Formation limestones provided a new site for pterosaurs, one that also preserved insects that fell into a brackish lagoon and semionotid fish preserved in phosphatized nodules. The fossils are usually compacted and preserved in layers of limestone. Fossil Odonata (dragonflies) and damselflies are especially rich in the Crato lagerstätte: currently 384 specimens have been recovered, 264 adults and 120 larvae. There are also plant remains. 1823 was a common year starting on Wednesday (see link for calendar). ... Suborders Rhamphorhynchoidea Pterodactyloidea Pterosaurs (TEH-row-sore, winged lizards) were flying reptiles of the clade Pterosauria. ... Suborders Anisoptera (dragonflies) Anisozygoptera Zygoptera (damselflies) Reference: ITIS 101593 as of 2002-07-26 Odonata is an order in the class Insecta, encompassing those insects commonly known as dragonflies (either when referring to the group as a whole or for the species in the suborder Anisoptera) and damselflies (for the... Families Aeshnidae Austropetaliidae Cordulegastridae Corduliidae Gomphidae Libellulidae Neopetaliidae Petaluridae Dragonflies have multifaceted compound eyes set close together The Dragonfly (suborder Anisoptera) is an insect belonging to the Order Odonata. ...

Local mining activities for cement and construction damage the sites. A trade in illegally-collected fossils has sprung up in the last decade, driven by the remarkablestate of preservation and beauty of these fossils. An urgent preservation program is being called for by paleontologists.

External link

• Maria Somália Sales Viana and Virgínio Henrique Lopes Neumann, "The Crato Member of the Santana Formation, Ceará State"

Further reading

• David Martill, 1996. Fossils of the Santana and Crato Formations, Brazil (Field Guide to Fossilsno. 5) (Blackwell) ISBN 0901702528