The island of Cajual is located in the

Baía de São Marcos The Baía de São Marcos is a bay of the Atlantic Ocean in Maranhão state of northeastern Brazil. The bay is an estuary approximately long and up to wide. It receives several rivers, including the Grajaú, Mearim, and Pindaré. The Mearim ...

near to

Alcântara, Maranhão Alcântara is a Brazilian municipality in the state of Maranhão. The city has a population of 22,112 (2020) and an area of 1458 km2. The municipality is 30 km away from the state's capital, São Luís. Founded by French explorers in th ...

, Brazil. The island is an important Brazilian paleontological site, where fossils of animals such as ''

Spinosaurus ''Spinosaurus'' (; ) is a genus of spinosaurid dinosaur that lived in what now is North Africa during the Cenomanian to upper Turonian stages of the Late Cretaceous period, about 99 to 93.5 million years ago. The genus was known first fro ...

'' and ''

Sigilmassasaurus ''Sigilmassasaurus'' ( ; "Sijilmassa lizard") is an extremely controversial genus of spinosaurid dinosaur that lived approximately 100 to 94 million years ago during the Late Cretaceous Period in what is now northern Africa. Named in 1996 by C ...

'' were found, and also such plants as

conifers Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All extan ...

and ferns. The finds include the remains of the largest carnivorous dinosaur in Brazil. Traces of the maxillary and nostril of the specimen were found. Known as ''Oxalaia quilombensis'', the species is part of the family of

dinosaurs Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

known as

Spinosauridae The Spinosauridae (or spinosaurids) are a clade or family of tetanuran theropod dinosaurs comprising ten to seventeen known genera. They came into prominence during the Cretaceous period. Spinosaurid fossils have been recovered worldwide, includin ...

, with elongated skulls and spines along the back. The presence of fossils also present in Africa proves that the continents were once united, forming

Gondwana Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages ...

. The "Lage of the Joker", where the fossils are found, is up to 2 meters below the water at high tide, so it can only be visited for only a few hours a day. Currently, the island of Cajual is home to a small community of ''

quilombola A ''quilombola'' () is an Afro-Brazilian resident of ''quilombo'' settlements first established by escaped slaves in Brazil. They are the descendants of Slavery in Brazil, Afro-Brazilian slaves who escaped from slave plantations that existed in ...

s''.

References

{{coord, -2.478, -44.486, type:isle_region:BR, display=title Landforms of Maranhão Atlantic islands of Brazil