Oxalaia
Encyclopedia
Oxalaia is a genus
of carnivorous theropod. It is a spinosaurine spinosaurid which lived during the late Cretaceous
(early Cenomanian
stage, about 98 mya) in what is now Brazil
.
Oxalaia is known from the holotype
MN
6117-V, fused premaxilla
e of a very large individual and from the referred fragment MN 6119-V, an isolated and incomplete left maxilla
, which were found on Cajual Island, Maranhão State of northeastern Brazil
. Fossils of Oxalaia were recovered in 2004 from the Laje do Coringa locality of the Alcântara Formation
, part of the Itapecuru Group of the São Luís Basin. Besides these bone fragments, numerous spinosaurid teeth had earlier been reported from the site.
The genus was named by Alexander Wilhelm Armin Kellner
, Sergio A.K. Azevedeo, Elaine B. Machado, Luciana B. Carvalho and Deise D.R. Henriques in 2011
and the type species
is Oxalaia quilombensis. The specific name quilombensis refers to the quilombo
settlements, such as on Cajual Island, which were founded by escaped slaves. Estimates suggest that it was 12 to 14 m (39.4 to 45.9 ft) in length and 5 to 7 t (5.5 to 7.7 ST) in weight —- it is the largest theropod known from Brazil and the eighth officially named species of theropod from Brazil.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of carnivorous theropod. It is a spinosaurine spinosaurid which lived during the late Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
(early Cenomanian
Cenomanian
The Cenomanian is, in the ICS' geological timescale the oldest or earliest age of the Late Cretaceous epoch or the lowest stage of the Upper Cretaceous series. An age is a unit of geochronology: it is a unit of time; the stage is a unit in the stratigraphic column deposited during the corresponding...
stage, about 98 mya) in what is now Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
.
Oxalaia is known from the holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
MN
National Museum of Brazil
The National Museum of Brazil is a centenarian museum and research institution, located in the Quinta da Boa Vista park in the city of Rio de Janeiro, Brazil.-History:...
6117-V, fused premaxilla
Premaxilla
The incisive bone is the portion of the maxilla adjacent to the incisors. It is a pair of small cranial bones at the very tip of the jaws of many animals, usually bearing teeth, but not always. They are connected to the maxilla and the nasals....
e of a very large individual and from the referred fragment MN 6119-V, an isolated and incomplete left maxilla
Maxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...
, which were found on Cajual Island, Maranhão State of northeastern Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
. Fossils of Oxalaia were recovered in 2004 from the Laje do Coringa locality of the Alcântara Formation
Alcântara Formation
The Alcântara Formation is a geological formation in northeastern Brazil whose strata date back to the Upper Cretaceous.-Fishes:-Crurotarsans:-Ornithodirans:...
, part of the Itapecuru Group of the São Luís Basin. Besides these bone fragments, numerous spinosaurid teeth had earlier been reported from the site.
The genus was named by Alexander Wilhelm Armin Kellner
Alexander Kellner
Alexander Wilhelm Armin Kellner is a Liechtensteinian/Brazilian paleontologist, a leading expert in the field of the study of pterosaurs....
, Sergio A.K. Azevedeo, Elaine B. Machado, Luciana B. Carvalho and Deise D.R. Henriques in 2011
2011 in paleontology
-Lobopods:-Arachnids:-Insects:-Newly named jawless vertebrates:-Newly named acanthodian:-Newly named cartilaginous fishes:-Newly named bony fishes:-Newly named lepospondyls:-Newly named temnospondyls:-Newly named lissamphibians:...
and the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
is Oxalaia quilombensis. The specific name quilombensis refers to the quilombo
Quilombo
A quilombo is a Brazilian hinterland settlement founded by people of African origin, Quilombolas, or Maroons. Most of the inhabitants of quilombos were escaped slaves and, in some cases, a minority of marginalised Portuguese, Brazilian aboriginals, Jews and Arabs, and/or other non-black,...
settlements, such as on Cajual Island, which were founded by escaped slaves. Estimates suggest that it was 12 to 14 m (39.4 to 45.9 ft) in length and 5 to 7 t (5.5 to 7.7 ST) in weight —- it is the largest theropod known from Brazil and the eighth officially named species of theropod from Brazil.