Aeolosaurini is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

titanosaur Titanosaurs (or titanosaurians; members of the group Titanosauria) 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 thr ...

ian dinosaurs known from the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

period of

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

and

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

. Rodrigo M. Santucci and Antonio C. de Arruda-Campos (2011) in their

cladistic Cladistics ( ; from Ancient Greek 'branch') is an approach to biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is ...

analysis found ''

Aeolosaurus ''Aeolosaurus'' (; "Aeolus' lizard") is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period (geology), Period of what is now South America. Like most sauropods, it would have been a quadrupedal herbivore with a long neck an ...

'', '' Gondwanatitan'', '' Maxakalisaurus'', ''

Panamericansaurus ''Panamericansaurus'' (meaning " Pan American Energy lizard") is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of Argentina. The holotype is very similar to known fossil material of ''Aeolosaurus'', which ''Panamerica ...

'' and ''

Rinconsaurus ''Rinconsaurus'' is a genus of titanosaur sauropod dinosaur from the Late Cretaceous in what is now Argentina. The type species, ''Rinconsaurus caudamirus'', was described by Calvo and Riga in 2003, and is based on three partial skeletons. Desc ...

'' to be aeolosaurids. Aeolosaurini is characterized by several

synapomorphies In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to ...

of the caudal vertebrae, such as angled centra, elongate prezygapophyses, and neural arches shifted anteriorly relative to the centra. In life, their tails may have been strongly curved downward as a result of these traits, which may have increased the force exerted by the caudofemoralis longus muscle in retracting the hindlimb. Some aeolosaurins, such as ''Shingopana'' and ''Overosaurus'', were relatively small compared to other titanosaurs, whereas others, such as ''Aeolosaurus maximus'', were large.

Phylogeny

Aeolosaurini was defined by Franco-Rosas, Salgado, Rosas and Carvalho (2004) as the

stem-based taxon Phylogenetic nomenclature is a method of nomenclature for taxon, taxa in biology that uses phylogenetics, phylogenetic definitions for taxon names as explained below. This contrasts with Biological classification, the traditional method, by which ...

that corresponds to the most-inclusive clade containing ''Aeolosaurus rionegrinus'' and ''Gondwanatitan faustoi'', but not '' Saltasaurus loricatus'' and ''

Opisthocoelicaudia skarzynskii ''Opisthocoelicaudia'' is a genus of sauropod dinosaur of the late Cretaceous, Late Cretaceous Period discovered in the Gobi Desert of Mongolia. The type species is ''Opisthocoelicaudia skarzynskii''. A well-preserved skeleton lacking only the ...

''.Franco-Rosas, A. C.; ''et al.'' (2004). Nuevos materiales de titanosaurios (Sauropoda) en el Cretácico Superior de Mato Grosso, Brasil ew materials of titanosaurs (Sauropoda) from the Upper Cretaceous of Mato Grosso, Brazil ''Revista Brasileira de Paleontologia''. 7(3): 329-336. Below is a

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

showing the phylogenetic relationships of Aeolosaurini-based Santucci and Arruda-Campos (2011), from Franca ''et al.'' (2016) on the left, and Silva ''et al.'' (2019) on the right.

References

{{Taxonbar, from=Q2334389 Lithostrotia