| Uberabatitan | |
|---|---|
 | |
| Life restoration | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Dinosauria |
| Clade: | Saurischia |
| Clade: | †Sauropodomorpha |
| Clade: | †Sauropoda |
| Clade: | †Macronaria |
| Clade: | †Titanosauria |
| Clade: | †Lithostrotia |
| Genus: | †Uberabatitan Salgado and Carvalho, 2008 |
| Type species | |
| †Uberabatitan ribeiroi Salgado and Carvalho, 2008 | |
Uberabatitan (meaning "Uberaba titan", in reference to where it was found) is agenus oftitanosauriansauropoddinosaur from theLate Cretaceous ofBrazil. It is known from bones including neck, back, and tailvertebrae,pelvic bones, and limb bones. Thesefossils were found in the uppermost portion of theMaastrichtian-ageSerra da Galga Formation of theBauru Group, in Uberaba,Minas Gerais. Thetype species, described by Salgado and Carvalho in 2008, isU. ribeiroi. To date, it is the most recent titanosaur from Bauru Group rocks; other titanosaurs from the Bauru Group, includingBaurutitan andTrigonosaurus, come from lower (thus older) levels.[1]
Uberabatitan ribeiroi was named byLeonardo Salgado and Ismar de Souza Carvalho in 2008,[1] based on specimens found at a road cut alongFederal Highway BR-050[2] inUberaba,Minas Gerais. The genus name refers to Uberaba and the species name honors Luiz Carlos Borges Ribeiro, the director of the Centro de Pesquisas Paleontológicas Lewellyn Price, for his support.[1]
Fossils ofUberabatitan ribeiroi have been found in theSerra da Galga Formation[a] inMinas Gerais,Brazil. All the specimens attributed toU. ribeiroi were found in a single quarry, and have been accessioned at the Centro de Pesquisas Paleontológicas Llewellyn Ivor Price (CPPLIP) at theFederal University of Triângulo Mineiro. More than sixty bones have been found, representing the intermingled remains of at least five individuals of various sizes[3] and ages, with both immature and mature individuals represented.[5] These remains includecervical,dorsal,sacral, andcaudal vertebrae,chevrons, and portions of the shoulders, hips, and limbs. As is commonly the case in titanosaurs, the skull is not known. Theholotype consists of thetibia (CPPLIP-912),fibula (CPPLIP-1107), andastragalus (CPPLIP-1082) of a single individual; other elements had initially been included in the holotype as well, but were excluded due to the lack of evidence that they came from the same individual.[3] Another specimen from the Serra da Galga Formation, MCT 1487-R, also known as "DGM Series A", exhibits close similarities toUberabatitan and may belong to it, or at least a close relative.[3] MCT 1487-R consists of a nearly complete neck, one of the few known for any titanosaur.[6] Two teeth found at theUberabatitan site, and others found elsewhere in the Serra da Galga Formation, may also belong toUberabatitan ribeiroi; one of these teeth, CPPLIP-1166, is the largest titanosaur tooth ever found, with acrown 6.2 centimetres (2.4 in) high from its base to its apex.[7]
As asauropod,Uberabatitan would have been a large, quadrupedal herbivore with a long neck.[8] It has been estimated thatUberabatitan ribeiroi could reach a length of 26 metres (85 ft), although most known specimens are of much smaller individuals.[3]
Although the skull ofUberabatitan is unknown, it may belong to a clade of titanosaurs that were characterized by a broad, squared-off snout.[9] The teeth possibly referable toUberabatitan are slender and chisel-like, as in other titanosaurs.[7]
As in many other sauropods,Uberabatitan had hyper-elongatecervical ribs, much of the length of which was formed byossified tendons.[5]
Thetibia andfibula ofUberabatitan exhibit some taxonomically significant traits. The tibia has a robust lateral protuberance that articulates with a medial knob on the fibula, which is anautapomorphy ofUberabatitan ribeiroi.[3] As inLaplatasaurus, but unlike most titanosaurs, there is a concave surface behind the lateral tuberosity of the fibula.[10]
Phylogenetic position ofUberabatitan in an analysis by Silva and colleagues in 2019:[3]
Possible close relatives ofUberabatitan includeLaplatasaurus andBrasilotitan. Gallina and Otero recoveredLaplatasaurus as thesister taxon ofUberabatitan in an analysis that did not includeBrasilotitan.[10] Navarro and colleagues and Filippi and colleagues have recoveredBrasilotitan as the sister taxon ofUberabatitan in analyses that did not includeLaplatasaurus.[11][9] Silva and colleagues regarded a close relationship betweenUberabatitan andBrasilotitan "possible"; their analysis recovered a polytomy ofBrasilotitan,Uberabatitan, and a clade containing other members ofAeolosaurini.[3] In an analysis that included neitherLaplatasaurus norBrasilotitan,Uberabatitan was recovered as a member of Aeolosaurini most closely related toBravasaurus,Gondwanatitan, andTrigonosaurus.[12]
Uberabatitan, like other sauropods, underwent rapid, uninterrupted growth early in life. Individuals closer to maturity would have transitioned to cyclical growth, with periodic slowdowns in their growth rate.[5]
