Ibirania Temporal range: Late Cretaceous | |
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Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | † Sauropodomorpha |
Clade: | † Sauropoda |
Clade: | † Macronaria |
Clade: | † Titanosauria |
Family: | † Saltasauridae |
Subfamily: | † Saltasaurinae |
Genus: | † Ibirania Navarro et al., 2022 |
Type species | |
†Ibirania parva Navarro et al., 2022 |
Ibirania (meaning "Ibirá wanderer" or "tree wanderer") is a genus of dwarf saltasaurine titanosaur dinosaur from the Late Cretaceous (Santonian to Campanian) São José do Rio Preto Formation (Bauru Basin) of Southeast Brazil. The type species is Ibirania parva. [1] It is one of the smallest sauropods known to date, comparable in size to the titanosaur Magyarosaurus . [2]
The Ibirania holotype specimen, LPP-PV-0200–0207, was discovered in layers of the São José do Rio Preto Formation on the Garcia Brothers Farm in Vila Ventura, Ibirá Municipality, northeastern São Paulo State, Brazil, which dates to the late Santonian to early Campanian ages of the late Cretaceous period. The holotype consists of a dorsal vertebra, partial caudal vertebrae, a fragmentary radius and ulna, a partial metacarpal, and a nearly complete metatarsal. Additional material, including partial cervical, dorsal, and caudal vertebrae, fragments of a fibula, and a nearly complete fibula, was also referred to Ibirania. [1]
In 2022, Navarro et al. described Ibirania as a new genus and species of saltasaurine titanosaur. The generic name, "Ibirania", combines a reference to Ibirá, the municipality where the specimens were discovered (also a Portuguese derivative of the Tupi word "ybyrá", meaning "tree", in reference to Ibirania's hypothesized browsing behavior), with "ania", a modified form of the Greek word "plania", meaning "wanderer". The specific name, "parva", is derived from the Latin word "parvus", meaning "small", after nanism seen in the taxon. The intended name meaning is "little Ibirá wanderer" or "little tree wanderer". [1]
Ibirania is estimated to be only 5.7 metres (19 ft) long, making it one of the smallest sauropods. [1]
Using computed tomography, Aureliano et al. (2021) discovered highly pneumatized vertebrae in the Ibirania holotype. Despite the nanoid status of Ibirania, the extreme pneumatization of its axial skeleton was inherited from its giant titanosaurian relatives. The histological thin sections of the vertebral bone revealed the preservation of pneumosteum throughout the internal trabeculae, definitive evidence of the preterit interaction of a bird-like air sac system in the bone. [3]
Ibirania was a derived member of the Saltasaurinae, a clade known for encompassing some of the smallest titanosaurs. Ibirania was recovered as sister taxa of the clade formed by the Patagonian saltasaurines Bonatitan and Rocasaurus .
The cladogram below displays the results of the phylogenetic analyses performed by Navarro et al. (2022): [1]
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One of the specimens of Ibirania (LPP-PV-0043, a partial fibula) presented a pathology called acute osteomyelitis. Aureliano et al. (2021) sampled histological thin sections of the lesion and described the step-by-step development of periosteal remodeling caused by the infection. They also used CT scan slices and a reconstructed 3D model to describe the trauma. [4]
Aureliano et al. (2021) also discovered fossilized parasites associated with the bone lesions in Ibirania (LPP-PV-0043). It was the first report of parasites preserved in situ inside the vascular canals of a dinosaur. The taxonomy of these microfossils are currently under study by the rest of the team. [4]
Ibirania lived in an arid, inland environment, which Navarro et al. (2022) presume is the reason behind its dwarfism. [1] This is in contrast to other dwarf sauropods such as Europasaurus and Magyarosaurus , which attained their small size due to insular dwarfism. [1]
It coexisted alongside other dinosaurs, such as the abelisaurid theropod Thanos simonattoi and a larger, unnamed probable megaraptoran, [5] as well as an indeterminate notosuchian. [6] [7]
Saltasaurus is a genus of saltasaurid dinosaur of the Late Cretaceous period of Argentina. Small among sauropods, though still heavy by the standards of modern creatures, Saltasaurus was characterized by a short neck and stubby limbs. It was the first genus of sauropod known to possess armour of bony plates embedded in its skin. Such small bony plates, called osteoderms, have since been found on other titanosaurians.
Sauropoda, whose members are known as sauropods, is a clade of saurischian ('lizard-hipped') dinosaurs. Sauropods had very long necks, long tails, small heads, and four thick, pillar-like legs. They are notable for the enormous sizes attained by some species, and the group includes the largest animals to have ever lived on land. Well-known genera include Apatosaurus, Argentinosaurus, Alamosaurus, Brachiosaurus, Camarasaurus, Diplodocus, and Mamenchisaurus.
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.
Alamosaurus is a genus of opisthocoelicaudiine titanosaurian sauropod dinosaurs containing a single known species, Alamosaurus sanjuanensis, from the Maastrichtian age of the Late Cretaceous period in what is now southwestern North America. Isolated vertebrae and limb bones indicate that it reached sizes comparable to Argentinosaurus and Puertasaurus, which would make it the absolute largest dinosaur known from North America. Its fossils have been recovered from a variety of rock formations spanning the Maastrichtian age. Specimens of a juvenile Alamosaurus sanjuanensis have been recovered from only a few meters below the Cretaceous-Paleogene boundary in Texas, making it among the last surviving non-avian dinosaur species. Alamosaurus is the only known sauropod to have inhabited North America after their nearly 30-million year absence from the North American fossil record and probably represents an immigrant from South America.
Bonatitan is a genus of titanosaurian dinosaur from the Late Cretaceous Allen Formation of Argentina. It was named in 2004.
Mendozasaurus is a genus of titanosaurian sauropod dinosaur. It was a member of Titanosauria, which were massive sauropods that were common on the southern landmasses during the Cretaceous. It is represented by several partial skeletons from a single locality within the Coniacian Sierra Barrosa Formation in the south of Mendoza Province, northern Neuquén Basin, Argentina. The type species, Mendozasaurus neguyelap, was described by Argentine paleontologist Bernardo Javier González Riga in 2003. Mendozasaurus is the first dinosaur named from Mendoza Province, Argentina, for which it was named.
Neuquensaurus is a genus of saltasaurid sauropod dinosaur that lived in the Late Cretaceous, about 80 million years ago in Argentina in South America. Its fossils were recovered from outcrops of the Anacleto Formation around Cinco Saltos, near the Neuquén river from which its name is derived.
Rocasaurus is a genus of titanosaurian sauropod that lived in South America. Rocasaurus was discovered in Argentina in 2000, within the Allen Formation which is dated to be middle Campanian to early Maastrichtian in age. This genus grew up to 8 metres (26 ft) long, making it one of the smaller sauropods. It seems to be closely related to saltasaurid dinosaurs, like Saltasaurus and Neuquensaurus.
Saltasauridae is a family of armored herbivorous sauropods from the Upper Cretaceous. They are known from fossils found in South America, Africa, Asia, North America, and Europe. They are characterized by their vertebrae and feet, which are similar to those of Saltasaurus, the first of the group to be discovered and the source of the name. The last and largest of the group and only one found in North America, Alamosaurus, was thirty-four metres in length and one of the last sauropods to go extinct.
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.
The Adamantina Formation is a geological formation in the Bauru Basin of western São Paulo state, in southeastern Brazil.
The Angostura Colorada Formation is a Campanian to Maastrichtian geologic formation of the Neuquén Basin and North Patagonian Massif in the Río Negro Province of Argentina. Dinosaur remains diagnostic to the genus level are among the fossils that have been recovered from the formation.
Opisthocoelicaudiinae is a subfamily of titanosaurian dinosaurs from the Late Cretaceous. It was named by John McIntosh in 1990. Opisthocoelicaudiines are known from Mongolia, Argentina, and the United States. Two genera were assigned to Opisthocoelicaudiinae by Gonzalez et al. (2009): Alamosaurus and Opisthocoelicaudia, a conclusion also found by Díez Díaz et al. (2018). The hands of opisthocoelicaudiines lacked wrist bones and phalanges.
Saltasaurinae is a subfamily of titanosaurian sauropods known from the late Cretaceous period of South America, India and Madagascar.
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.
Thanos is a genus of carnivorous brachyrostran abelisaurid dinosaur that lived in Brazil during the Santonian stage of the late Cretaceous Period. It contains only a single species known as T. simonattoi.
Menucocelsior is a genus of medium-sized titanosaurian sauropod dinosaur from the Late Cretaceous Allen Formation of Argentina. The type and only species is Menucocelsior arriagadai.
Udelartitan is an extinct genus of saltasauroid titanosaurian sauropod dinosaur from the Late Cretaceous Guichón Formation of Uruguay. The genus contains a single species, U. celeste, known from fragmentary remains of at least two individuals.