Patagopelta Temporal range: Late Cretaceous | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | † Ornithischia |
Clade: | † Thyreophora |
Clade: | † Ankylosauria |
Clade: | † Parankylosauria (?) |
Genus: | † Patagopelta Riguetti et al., 2022 |
Species: | †P. cristata |
Binomial name | |
†Patagopelta cristata Riguetti et al., 2022 | |
Patagopelta (meaning "Patagonian shield") is an extinct genus of ankylosaurian dinosaur from the Late Cretaceous (upper Campanian–lower Maastrichtian) Allen Formation of Argentina. The genus contains a single species, P. cristata, known from a partial skeleton. While originally described as a nodosaurine, later discoveries provided support for parankylosaurian affinities for the taxon. Patagopelta is a very small ankylosaur, comparable in size to the dwarf nodosaurid Struthiosaurus , about 2 m (6.6 ft) long.
The Patagopelta fossil material was found in sediments of the Allen Formation (Salitral Moreno locality) near General Roca, Río Negro Province, Argentina. This locality is dated to the upper Campanian to lower Maastrichtian ages of the Late Cretaceous period. The first remains were described in 1996 and often appeared in the literature as the "Argentinian ankylosaur". [1] [2] The fossil material consists of various osteoderms, a tooth, dorsal and caudal vertebrae, and femora. The Patagopelta holotype specimen, MPCA-SM-78, is represented by a cervical half-ring element. [3]
New remains described in 2022 allowed Patagopelta cristata to be described as a new genus and species of nodosaurine dinosaurs by Facundo Riguetti, Xabier Pereda-Suberbiola, Denis Ponce, Leonardo Salgado, Sebastián Apesteguía, Sebastián Rozadilla, and Victoria Arbour. The generic name, "Patagopelta", is derived from "Patago", a reference to the discovery of the taxon in Argentinian Patagonia, and the Greek word "pelta", meaning "shield". The specific name, "cristata", means "crested" in Latin, referring to the large crests on its cervical osteoderms and femur. [3]
In their phylogenetic analyses, Riguetti et al. (2022) recovered Patagopelta as a member of the Nodosaurinae, within a clade of entirely North American nodosaurids from the middle of the Cretaceous period, in contrast to previous analyses that recovered it in the Panoplosaurini. [4] In either case, these results would suggest that nodosaurids were part of a migration event of North American fauna into South America. The cladogram below displays the results of their phylogenetic analyses. [3]
Nodosauridae |
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
A study published in 2024 by Agnolín and colleagues reviewed vertebrate fossils from the Cerro Fortaleza Formation and similar Patagonian formations. They mentioned new findings that suggest that Patagopelta may actually represent a parankylosaurian, similar to ankylosaurs like Antarctopelta rather than nodosaurids. [5] In their 2024 redescription of Antarctopelta , Soto Acuña, Vargas & Kaluza further elaborated on this, explaining that the discovery of additional fossil material allowed for a rescoring of its characters in their phylogenetic matrix. Based on these updates, they recovered Patagopelta within the Parankylosauria, along with other Cretaceous Gondwanan ankylosaurs. Their results are displayed in the cladogram below: [6]
Ankylosauria |
| |||||||||||||||||||||
Patagopelta is known from the Late Cretaceous Allen Formation of Río Negro Province, Argentina. Many other dinosaurs, including titanosaurs ( Aeolosaurus , Bonatitan , Menucocelsior , Panamericansaurus , Pellegrinisaurus , and Rocasaurus ), hadrosaurids ( Bonapartesaurus , Kelumapusaura , and Lapampasaurus ), abelisaurids ( Niebla and Quilmesaurus ), dromaeosaurids ( Austroraptor ), and alvarezsaurids ( Bonapartenykus ), have been named from the formation. Birds ( Lamarqueavis and Limenavis ), pterosaurs ( Aerotitan ), rhynchocephalians ( Lamarquesaurus ), plesiosaurs ( Kawanectes ), and dryolestoid and gondwanathere mammals have also been described from the formation. [3] [7] [8]
Ankylosauria is a group of herbivorous dinosaurs of the clade Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms, similar to turtles. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. They are known to have first appeared in the Middle Jurassic, and persisted until the end of the Cretaceous Period. The two main families of Ankylosaurs, Nodosauridae and Ankylosauridae are primarily known from the Northern Hemisphere, but the more basal Parankylosauria are known from southern Gondwana during the Cretaceous.
Nodosauridae is a family of ankylosaurian dinosaurs, from the Late Jurassic to the Late Cretaceous period in what is now North America, South America, Europe, and Asia.
Secernosaurus is a genus of herbivorous dinosaur. Secernosaurus was a hadrosaur, a "duck-billed" dinosaur which lived during the Late Cretaceous.
Texasetes is a genus of ankylosaurian dinosaurs from the late Lower Cretaceous of North America. This poorly known genus has been recovered from the Paw Paw Formation near Haslet, Tarrant County, Texas, which has also produced the nodosaurid ankylosaur Pawpawsaurus.
Lametasaurus named for the Lameta Formation, Jabalpur, India, is the generic name given to a possibly chimeric dinosaur species. The type species is L. indicus.
The Huincul Formation is a geologic formation of Late Cretaceous age of the Neuquén Basin that outcrops in the Mendoza, Río Negro and Neuquén Provinces of northern Patagonia, Argentina. It is the second formation in the Río Limay Subgroup, the oldest subgroup within the Neuquén Group. Formerly that subgroup was treated as a formation, and the Huincul Formation was known as the Huincul Member.
The Los Alamitos Formation is a geological formation of the North Patagonian Massif in Rio Negro Province, northwestern Patagonia, Argentina, whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.
The Allen Formation is a geological formation in Argentina whose strata date back to the Late Cretaceous (middle Campanian to early Maastrichtian. Dinosaur remains are among the fossils that have been recovered from the formation. Indeterminate chelid remains and other vertebrates have also been discovered in this formation.
The Chorrillo Formation, also named as Chorillo Formation, is a Maastrichtian geologic formation in southern Patagonia, Argentina. The formation is more than 50 metres (160 ft) thick and underlies the Calafate Formation and rests on top of the La Irene Formation.
Bonapartenykus is a monospecific genus of alvarezsauroid dinosaur from Argentina that lived during the Late Cretaceous (Campanian-Maastrichtian) in what is now the upper Allen Formation of the Río Negro Province. The type and only species, Bonapartenykus ultimus, is known from a nearly articulated but partial skeleton that was found in close association to two incomplete eggs and several clusters of eggshells belonging to the oogenus Arriagadoolithus. Bonapartenykus was named in 2012 by Federico L. Agnolin, Jaime E. Powell, Fernando E. Novas and Martin Kundrát. Bonapartenykus has an estimated length of 2.5 m (8.2 ft) and weight of 72 kg (159 lb), making it the largest member of the clade Alvarezsauroidea.
Kritosaurini is a tribe of saurolophine hadrosaurid dinosaurs from the Late Cretaceous.
Niebla is a genus of abelisaurid theropod dinosaur from the Late Cretaceous Period (Campanian-Maastrichtian) of Río Negro province, Argentina. The genus contains a single species, Niebla antiqua, and is known from a partial, non-articulated skeleton. The holotype, found in the Allen Formation, represents an adult individual.
Parankylosauria is a group of basal ankylosaurian dinosaurs known from the Cretaceous of South America, Antarctica, and Australia. It is thought the group split from other ankylosaurs during the mid-Jurassic period, despite this being unpreserved in the fossil record.
Panoplosaurini is a clade of nodosaurid ankylosaurs from the Cretaceous of North America and South America. The group is defined as the largest clade containing Panoplosaurus mirus, but not Nodosaurus textilis or Struthiosaurus austriacus, and was named in 2021 by Madzia and colleagues for the group found in many previous analyses, both morphological and phylogenetic. Panoplosaurini includes not only the Late Cretaceous Panoplosaurus, Denversaurus and Edmontonia, but also the mid Cretaceous Animantarx and Texasetes, as well as Patagopelta. However, in the study describing it, its authors only placed it as a nodosaurine outside Panoplosaurini. The approximately equivalent clade Panoplosaurinae, named in 1929 by Franz Nopcsa, but was not significantly used until Robert Bakker reused the name in 1988, alongside the new clades Edmontoniinae and Edmontoniidae, which were considered to unite Panoplosaurus, Denversaurus and Edmontonia to the exclusion of other ankylosaurs. As none of the clades were commonly used, or formally named following the PhyloCode, Madzia et al. named Panoplosaurini instead, as the group of taxa fell within the clade Nodosaurinae, and having the same -inae suffix on both parent and child taxon could be confusing in future. The 2018 phylogenetic analysis of Rivera-Sylva and colleagues was used as the primary reference for Panoplosaurini by Madzia et al., in addition to the supplemental analyses of Arbour et al. (2016), Brown et al. (2017), and Zheng et al. (2018).
Huallasaurus is an extinct genus of saurolophine hadrosaur from the Late Cretaceous Los Alamitos Formation of Patagonia in Argentina. The type and only species is H. australis. Originally named as a species of Kritosaurus in 1984, it was long considered a synonym of Secernosaurus before being recognized as its own distinct genus in a 2022 study, different from other members of Kritosaurini.
Kelumapusaura is a genus of saurolophine hadrosaur from the Late Cretaceous Allen Formation in what is now Patagonia in Argentina. The type and only species is K. machi, known from a bonebed of various individuals.
Maip is a genus of large megaraptorid theropod dinosaur from the Late Cretaceous (Maastrichtian) Chorrillo Formation of Santa Cruz, Argentina. The genus contains a single species, M. macrothorax, known from an incomplete, disarticulated skeleton. Maip may represent the largest megaraptorid known from South America, and possibly the world.
Yatenavis is an extinct genus of enantiornithine bird from the Late Cretaceous Chorrillo Formation of Santa Cruz Province, Argentina. The genus contains a single species, Y. ieujensis, known from a partial humerus.
Austrokritosauria is an extinct clade of saurolophine dinosaurs known from the Late Cretaceous of South America. The clade provides evidence of a faunal exchange from North America during the Cretaceous.
Chakisaurus is an extinct genus of elasmarian ornithopod dinosaur from the Late Cretaceous Huincul Formation of Argentina. The genus contains a single species, C. nekul, known from multiple partial skeletons belonging to individuals of different ages. Chakisaurus represents the first ornithischian species to be named from the Huincul Formation.