The holotype, an incomplete, about 201mm long premaxilla.

  • Brazil ( Alcântara Formation)
  • Oxalaia quilombensis

Oxalaia is a genus of large theropod dinosaur from the family Spinosauridae. Only species described is Oxalaia quilombensis. So far, only jaw fragments are known.


Oxalaia is named after the creator god Obatala yorubaischen, while the second part of the species name, quilombensis, derived from the Portuguese quilombo, "the place where the quilombola live." The quilombola are descendants of former Brazilian slaves who are native to the island Cajual on which the fossils were found.


Oxalaia reached a length of about 12 to 14 meters, its weight is estimated to be five to seven tonnes. He is the far largest theropod found in Brazil and one of the largest known land predators of the earth's history. He was surpassed only by his relatives Spinosaurus and some representatives of the Carcharodontosauridae.

The holotype consists of the incomplete paarigem, about 201 mm long premaxilla, which once bore seven teeth. In addition, the genus is attributed to a fragment of the left maxilla. The entire head is estimated to have a length of 135 cm.


Oxalaia differs from the African Spinosaurus in the number of teeth on the premaxilla and the distance between the individual teeth. From the Baryonychinae, a subfamily of Spinosauriden to Oxalaia can distinguish on the third tooth socket on the basis of ungesägten teeth and the two replacement teeth. The latter is unique for a theropod. Oxalaia is counted among the Spinosaurinae. Among his closest relatives therefore include Spinosaurus and the Angaturama also found in Brazil.


The fossils of Oxalaia were found in northeastern Brazil in the rocks of the Alcântara Formation, which can be dated to the early Late Cretaceous ( Cenomanian ). From the same formation hundreds of other teeth of Spinosauriden are known. Some of the teeth can Oxalaia, others may belong to a previously unknown type.


  • Alexander WA. waiter; Sergio A.K. Azevedo; Elaine B. Machado; Luciana B. de Carvalho; Deise D. R. Henriques: A new dinosaur ( Theropoda, Spinosauridae ) from the Cretaceous ( Cenomanian ) Alcântara Formation, Cajual Iceland, Brazil. In: Anais da Academia Brasileira de Ciências. 83, No. 1, 2011, doi: 10.1590/S0001-37652011000100006.