Cerrejón Formation

Titanoboa (; ) is a genus of extinct giant boid snake (being the biological family of all boas and anacondas) that lived during the middle and late Paleocene epoch. Titanoboa was first discovered in the early 2000s by members of the Smithsonian Tropical Research Institute, which–along with students from the University of Florida–recovered 186 fossils of Titanoboa from the Cerrejón coal mines in the La Guajira department of northeastern Colombia. It was named and described in 2009 as Titanoboa cerrejonensis, and lauded as the largest snake ever found at that time. The original type

Carbonemys cofrinii is an extinct giant podocnemidid turtle known from the Middle Paleocene Cerrejón Formation of the Cesar-Ranchería Basin in northeastern Colombia. The formation is dated to approximately 60 to 57 million years ago, beginning about five million years after the KT extinction event.

Cerrejón is a large open-pit coal mine in Northern Colombia owned by Glencore. At Cerrejón, low-ash, low-sulphur bituminous coal from the Cerrejón Formation is excavated. At over the mine is one of the largest of its type, the largest in Latin America and the tenth biggest in the world. Cerrejón is divided into three sections, North Zone, Central Zone and South Zone. Total proven reserves are estimated at 503 megatonnes. In 2016, the mine produced .

Cerrejonisuchus is an extinct genus of dyrosaurid crocodylomorph. It is known from a complete skull and mandible from the Cerrejón Formation in northeastern Colombia, which is Paleocene in age. Specimens belonging to Cerrejonisuchus and to several other dyrosaurids have been found from the Cerrejón open-pit coal mine in La Guajira. The length of the rostrum is only 54-59% of the total length of the skull, making the snout of Cerrejonisuchus the shortest of all dyrosaurids.

Acherontisuchus is an extinct genus of dyrosaurid neosuchian from Middle to Late Paleocene deposits of Colombia. The only known species is A. guajiraensis, whose name means "Acheron crocodile of the Guajira Peninsula".

Puentemys is an extinct genus of bothremydid turtle from the Paleocene-age Cerrejón Formation in Colombia. It is the largest known bothremydid, with a shell length of up to . Puentemys is the only Paleocene bothremydid known from South America, and is most closely related to the genus Foxemys from the Late Cretaceous of Europe, showing that Bothremydini, the tribe of bothremydids to which Puentemys belonged, had a nearly worldwide distribution across the K-T boundary. The ancestors of Puentemys may have reached South America by dispersing across Paleocene coastlines or by riding currents acros