The Alcântara Formation is a geological formation in northeastern Brazil whose strata date back to the Cenomanian of the Late Cretaceous.
Fossil content
Dinosaurs
Ornithischians Ornithischians of the Alcântara FormationGenusSpeciesLocationStratigraphic positionMaterialNotesImage Ornithopoda indet. Indeterminate Laje do Coringa, Cajual Island Footprints Footprints interpreted as coming from both small and large ornithopods. Larger footprints have been tentatively assigned to hadrosaurs.
Sauropods Sauropods of the Alcântara Formation Genus Species Location Stratigraphic position Material Notes Images Itapeuasaurus I. cajapioensis Itapeua beach A rebbachisaurine rebbachisaurid cf. Limaysaurus L. tessonei Laje do Coringa, Cajual Island Vertebrae A limaysaurine rebbachisaurid cf. Malawisaurus? M. sp. Laje do Coringa, Cajual Island Tooth A tooth similar to Malawisaurus Sauropoda indet. Indeterminate Laje do Coringa, Cajual Island Teeth May belong to a titanosaurian or a diplodocoid rebbachisaurid Titanosauria indet. Indeterminate Laje do Coringa, Cajual Island Vertebrae and an osteoderm A titanosaurian sauropod
Theropods Theropods of the Alcântara Formation Genus Species Location Stratigraphic position Material Notes Images Abelisauridae indet. Indeterminate Laje do Coringa, Cajual Island Two shed tooth crowns A abelisaurid theropod Carcharodontosauridae indet. Indeterminate Laje do Coringa, Cajual Island Teeth A carcharodontosaurid theropod Noasaurinae indet. Indeterminate Laje do Coringa, Cajual Island Nine teeth A noasaurine noasaurid; closely related to Masiakasaurus knopfleri. Oxalaia O. quilombensis Laje do Coringa, Cajual Island Fused premaxillae; isolated and incomplete left maxilla (both heavily damaged from the National Museum of Brazil fire) A spinosaurin spinosaurine which may be synonymus with Spinosaurus itself. However, this has been disputed. SigilmassasaurusS. brevicollisLaje do Coringa, Cajual IslandTwo caudal vertebraeReferral to Sigilmassasaurus was based on similarity to presumed caudal vertebrae of the genus from the Kem Kem Group. However, the 2022 study noted that these specimens are indeterminate spinosaurids, most likely belonging to Oxalaia considering the geographical and geological context. Spinosaurini indet. Indeterminate Laje do Coringa, Cajual Island TeethA spinosaurin spinosaurine different from Oxalaia. Unenlagiinae Indet. Indeterminate Laje do Coringa, Cajual Island, São Luís-Grajaú Basin Teeth A unenlagiine dromaeosaurid
Pterosauria Pterosaurs of the Alcântara Formation Genus Species Location Stratigraphic position Material Notes Images Anhangueridae indet. Indeterminate Laje do Coringa, Cajual Island Teeth A anhanguerid pterosaur Ornithocheiroidea Indet. Indeterminate Laje do Coringa, Cajual Island Tooth A ornithocheiroid pterosaur
Crocodylomorphs Crocodylomorphs of the Alcântara Formation Genus Species Location Stratigraphic position Material Notes Images Candidodon C. itapecuruense Laje do Coringa, Cajual Island Teeth A candidodontid notosuchian Coringasuchus C. anisodontis Laje do Coringa, Cajual Island Partial right dentary A ziphosuchian notosuchian
Turtles Turtles of the Alcântara Formation Genus Species Location Stratigraphic position Material Notes Images Pelomedusoides indet. Indeterminate Laje do Coringa, Cajual Island Incomplete carapace A side-necked turtle
Squamates Squamates of the Alcântara Formation Genus Species Location Stratigraphic position Material Notes Images Seismophis S. septentrionalis Laje do Coringa, Cajual Island Vertebrae A snake
Mosasaurs Mosasaurs of the Alcântara Formation Genus Species Location Stratigraphic position Material Notes Images Carinodens C. fraasi Laje do Coringa, Cajual Island Dental A globidensin mosasaurine Mosasauridae Indet. Indeterminate Laje do Coringa, Cajual Island An indeterminate mosasaurid
Plesiosaurs Plesiosaurs of the Alcântara FormationGenusSpeciesLocationStratigraphic positionMaterialNotesImage Brachaucheninae Indet. Indeterminate Laje do Coringa, Cajual Island Teeth A brachauchenine thalassophonean
Fish Fishes of the Alcântara Formation Genus Species Location Stratigraphic position Material Notes Images Adrianaichthys A. pankowski Laje do Coringa, Cajual Island ScalesA lepisosteiform fish Aegyptobatus A. kuehnei Laje de Coringa, Cajual Island A distobatid hybodont Arganodus A. tiguidiensis Laje do Coringa, Cajual Island Dental plates A arganodontid lungfish Atlanticopristis A. equatorialis Falésia do Sismito and Laje do Coringa, Cajual Island Fourteen denticle specimens (two complete) A sclerorhynchoid Bartschichthys B. sp. Laje do Coringa, Cajual Island Spines A cladistian Ceratodus C. brasiliensis Laje do Coringa, Cajual Island Dental plates A ceratodontid lungfish C. humei Distobatus D. nutiae Laje de Coringa, Cajual Island Teeth A distobatid hybodont Equinoxiodus E. alcantarensis Laje do Coringa, Cajual Island One complete and eight incomplete tooth plates A neoceatodontid lungfish E. schuitzei Hybodontidae Indet. Indeterminate Laje de Coringa, Cajual Island Teeth & Cephalic spines A hybodontid hybodont Hylaeobatis H. sp. Laje do Coringa, Cajual Island Tooth A ptychodontid lamniform Lepidotes L. sp. Laje do Coringa, Cajual Island Mineralized scales A lepidotid fish. Lepisosteidae Indet. Indeterminate Laje do Coringa, Cajual Island Scales A gar Lonchidiidae Indet. Indeterminate Laje de Coringa, Cajual Island Teeth & Dorsal Spines A lonchidiid hybodont MawsoniaMedeiros, M.A., Carvalho, M.S.S., Silva, M.A.M., Pereira, A.A., Araujo, M.N., Ferreira, N.N., Vilas Bôas, I., 2011. O senhor dos rios: Mawsonia gigas (Mawsoniidae) do Cenomaniano do Maranhão, Brasil. In: Carvalho, I.S., Srivastava, N.K., Strohschoen, J.O., Lana, C.C. (Eds.), Paleontologia: Cenários de Vida, Vol. 4. Interciência, Rio de Janeiro, pp. 575-583. M. gigas Laje do Coringa, Cajual Island Palato-quadrate and post-parietal cranial material A mawsoniid coelacanth. Myliobatis M. dixoni Laje do Coringa, Cajual Island A myliobatid eagle ray Obaichthys O. africanus Laje do Coringa, Cajual Island Scales A obaichthyid lepisosteiform Onchopristis cf. O. numida Laje do Coringa, Cajual Island Rostral teeth A sclerorhynchoid Pycnodontiformes indet. Indeterminate Laje do Coringa, Cajual Island Dental plate and teeth Stephanodus S. sp. Laje do Coringa, Cajual Island Pharyngeal teeth A pycnodontid pycnodont Tribodus T. limae Laje do Coringa, Cajual Island Dorsal spines A hybodont shark
Plants Plants of the Alcântara FormationGenusSpeciesLocationStratigraphic positionMaterialNotesImage Araucariaceae Indet. Indeterminate Laje do Coringa, Cajual Island Log A pine Paradoxopteris P. sanctiluigi Laje do Coringa, Cajual Island Stalk fragment A giant tree fern
References