Maxakalisaurus Temporal range: Late Cretaceous | |
---|---|
Reconstructed skeleton | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | † Sauropodomorpha |
Clade: | † Sauropoda |
Clade: | † Macronaria |
Clade: | † Titanosauria |
Clade: | † Lithostrotia |
Genus: | † Maxakalisaurus Kellner et al., 2006 |
Species: | †M. topai |
Binomial name | |
†Maxakalisaurus topai Kellner et al., 2006 | |
Maxakalisaurus is a genus of titanosaur dinosaur, found in the Adamantina Formation of Brazil, in the state of Minas Gerais in 1998. The genus name is derived from the tribe of the Maxakali; Topa is one of their divinities. [1]
Over the course of four field seasons, from 1998 to 2002, the National Museum of Brazil excavated a partial skeleton of a titanosaur along the Campina Verde - Prata road, 45 km to the west of Prata, Minas Gerais. In 2006, a team led by Alexander W. A. Kellner described the remains as a new genus and species of sauropod, Maxakalisaurus topai. The genus name honors the Maxakali, an ethnic group indigenous to the region, and the species name refers to the Maxakali deity Topa. [1]
Fossils of Maxakalisaurus topai are known from the Adamantina Formation. The holotype, MN 5013-V, was housed at the National Museum of Brazil. [1] [2] It included a fragmentary right maxilla with teeth, twelve cervical vertebrae and some cervical ribs, seven dorsal vertebrae and some dorsal ribs, a neural spine and centrum from the sacrum, six caudal vertebrae, some haemal arches, pieces of the scapulae, both sternal plates, part of the left ischium, both humeri, two metacarpals, part of the fibula, an osteoderm, and some unidentified pieces. Two other sternal plates and part of a third scapula were also found at the site, and are considered to belong to a second individual. [1] Some of the elements from the type locality pertained to an adult individual and others pertained to a subadult individual. [3] A partial dentary and some teeth were subsequently recovered from the type locality and are also considered to belong to M. topai. [4] Some elements of the holotype were lost in the National Museum of Brazil fire on 2 September 2018, but several elements survived the fire and were recovered. [3]
Maxakalisaurus is considered a medium-sized titanosaur. [1] [5] The type specimen of Maxakalisaurus belonged to an animal about 12.1 meters (40 feet) long, with an estimated weight of 5 tonnes (5.5 short tons). [1] [6] It had a long neck and tail, ridged teeth (unusual among sauropods) and lived about 80 million years ago. Because sauropods seem to have lacked significant competition in South America, they evolved there with greater diversity and more unusual traits than elsewhere in the world. Like many other titanosaurs, Maxakalisaurus had osteoderms. [1]
França et al.'s 2016 description of the second specimen also included a phylogenetic analysis, which placed Maxakalisaurus as a basal member of the Aeolosaurini. Their cladogram is shown below: [4]
Titanosaurs were a diverse group of sauropod dinosaurs, including genera from all seven continents. The titanosaurs were the last surviving group of long-necked sauropods, with taxa still thriving at the time of the extinction event at the end of the Cretaceous. This group includes some of the largest land animals known to have ever existed, such as Patagotitan—estimated at 37 m (121 ft) long with a weight of 69 tonnes —and the comparably-sized Argentinosaurus and Puertasaurus from the same region.
Aeolosaurus is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. Like most sauropods, it would have been a quadrupedal herbivore with a long neck and tail. Aeolosaurus is well known for a titanosaur, as it is represented by the remains of several individuals belonging to at least two species. However, like most titanosaurs, no remains of the skull are known. The holotype of Aeolosaurus rionegrinus consists of a series of seven tail vertebrae, as well as parts of both forelimbs and the right hindlimb. It was discovered in the Angostura Colorada Formation in Argentina, which dates from the Campanian stage of the Late Cretaceous, about 83 to 74 million years ago. The species A. maximus was transferred over to the new genus Arrudatitan in 2021.
Gondwanatitan was a titanosaurian sauropod dinosaur. Gondwanatitan was found in Brazil, at the time part of the southern supercontinent Gondwana, in the late Cretaceous Period. Like some other sauropods, Gondwanatitan was tall and ate tough shoots and leaves off of the tops of trees. G. faustoi's closest relative was Aeolosaurus.
Malawisaurus is an extinct genus of titanosaurian sauropod dinosaur. It is known from the Dinosaur Beds of northern Malawi, which probably date to the Aptian stage of the Early Cretaceous. The type species is M. dixeyi and the specific name honours Frederick Augustus Dixey.
Nemegtosaurus was a sauropod dinosaur from the Late Cretaceous Period of what is now Mongolia. It was named after the Nemegt Basin in the Gobi Desert, where the remains — a single skull — were found. The skull resembles diplodocoids in being long and low, with pencil-shaped teeth. However, recent work has shown that Nemegtosaurus is in fact a titanosaur, closely related to animals such as Saltasaurus, Alamosaurus and Rapetosaurus.
Adamantisaurus is a poorly-known genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. It is only known from six tail vertebrae but, as a sauropod, it can be assumed that this dinosaur was a very large animal with a long neck and tail.
Baurutitan is a genus of sauropod dinosaur that lived during the Late Cretaceous in what is now Brazil. The type species, Baurutitan britoi, was described in 2005 by Kellner and colleagues, although the fossil remains had already been discovered in 1957. Baurutitan is classified as a lithostrotian titanosaur, and is distinguished from related genera based on its distinctive caudal vertebrae. This South American dinosaur was found in the Serra da Galga Formation near Uberaba, in the Brazilian state of Minas Gerais.
Muyelensaurus is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous of Argentina. It was more slender than other titanosaurs. Fossils have been recovered in the Neuquén province of Patagonia and were originally assigned to the Portezuelo Formation but further research showed that these layers belong to the Plottier Formation. The type species is M. pecheni. The name Muyelensaurus first appeared in a 2007 paper by Argentine paleontologists Jorge Calvo of the Universidad Nacional del Comahue and Bernardo González Riga of the Laboratorio de Paleovertebrados, and Brazilian paleontologist Juan Porfiri of the Universidade Federal do Rio de Janeiro.
Uberabatitan is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous of Brazil. It is known from bones including neck, back, and tail vertebrae, pelvic bones, and limb bones. These fossils were found in the uppermost portion of the Maastrichtian-age Serra da Galga Formation of the Bauru Group, in Uberaba, Minas Gerais. The type species, described by Salgado and Carvalho in 2008, is U. ribeiroi. To date, it is the most recent titanosaur from Bauru Group rocks; other titanosaurs from the Bauru Group, including Baurutitan and Trigonosaurus, come from lower levels.
Peirosaurus is an extinct genus of peirosaurid crocodylomorph known from the Late Cretaceous period of Minas Gerais, southern Brazil. It contains a single species, Peirosaurus torminni. It is the type genus of the family Peirosauridae.
Lognkosauria is a clade of giant long-necked sauropod dinosaurs within the clade Titanosauria. It includes some of the largest and heaviest dinosaurs known. They lived in South America and likely Asia during the Late Cretaceous period.
Aeolosaurini is an extinct clade of titanosaurian dinosaurs known from the Cretaceous period of Argentina and Brazil. Rodrigo M. Santucci and Antonio C. de Arruda-Campos (2011) in their cladistic analysis found Aeolosaurus, Gondwanatitan, Maxakalisaurus, Panamericansaurus and Rinconsaurus to be aeolosaurids.
Brasilotitan is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Adamantina Formation of Brazil. The type species is Brasilotitan nemophagus. Brasilotitan was a small titanosaur with a squared-off snout, and may be closely related to another Brazilian titanosaur, Uberabatitan.
Austroposeidon is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Presidente Prudente Formation of Brazil. It contains one species, Austroposeidon magnificus.
Rinconsauria is an extinct clade of giant titanosaurian sauropods known from the late Cretaceous period of Argentina.
Arrudatitan is an extinct genus of titanosaur sauropod dinosaur known from the Late Cretaceous (Campanian-Maastrichtian)-aged Adamantina Formation of Brazil. The type species, A. maximus, was named and described in 2011 as a species of Aeolosaurus, but was separated into its own genus in 2021. It was relatively gracile for a titanosaur.
Aphaurosuchus is an extinct genus of baurusuchid mesoeucrocodylian known from the Late Cretaceous Bauru Basin of São Paulo, southern Brazil. It contains two species, Aphaurosuchus escharafacies and Aphaurosuchus kaiju.
Saltasauroidea is a superfamily of titanosaurs named by França and colleagues in 2016 based on their phylogenetic results, for a clade uniting Aeolosaurini and Saltasauridae, as well as the intermediate genera Baurutitan, Diamantinasaurus and Isisaurus. The group was not defined or discussed in the text, but was supported by Carballido and colleagues in 2022 as a useful designation for subdividing titanosaurs. As there was no discussion about the intentions for the clade, Carballido gave it the definition of all taxa closer to Saltasaurus than Patagotitan, encompassing half of Eutitanosauria as the sister taxon to the inversely defined Colossosauria. Carballido et al. placed Nemegtosauridae and Saltasauridae within the group, though they had Aeolosaurini within Colossosauria. The informal cladogram of titanosaur relationships they proposed is shown below.
Ibirania is a genus of dwarf saltasaurine titanosaur dinosaur from the Late Cretaceous São José do Rio Preto Formation of Southeast Brazil. The type species is Ibirania parva. It is one of the smallest sauropods known to date, comparable in size to the titanosaur Magyarosaurus.
Caieiria is a genus of titanosaurian dinosaur from the Late Cretaceous Serra da Galga Formation of Brazil. The type and only species is Caieiria allocaudata.