Teviornis Temporal range: Late Cretaceous, | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Family: | † Presbyornithidae |
Genus: | † Teviornis Kurochkin, Dyke & Karhu, 2002 |
Species: | †T. gobiensis |
Binomial name | |
†Teviornis gobiensis Kurochkin, Dyke & Karhu, 2002 | |
Teviornis is an extinct genus of presbyornithid which lived during the Maastrichtian stage, around 70 million years ago. One species has been described, T. gobiensis. It is the oldest known neognath and its fossils are collected from the Nemegt Formation of Mongolia. [1]
The fossils were collected at the Gurilyn tsav locality, northwest corner of Umnogobi Aimak, Mongolia. The holotype consists of a crushed partial right forelimb. These pieces include a nearly complete right carpometacarpus, two phalanges, the radiale and ulnare of the wrist, and a fragment of the distal right humerus. The catalog number of these fossils are given multiple times as PIN 4499–1, but they are listed as PIN 44991–1 on page 3, where the holotype is formally listed. This is probably a misprint. [2]
The genus name Teviornis is the Greek masculine word for bird combined with the name of Victor Tereschenko, the Paleontologist at the PIN who discovered the specimen. The species name T. gobiensis refers to the harsh Gobi Desert in which the fossil was found. The fossils are in the collection of the Paleontological Institute, Russian Academy of Sciences, Moscow. [2]
In 2002, Teviornis was described by Kurochkin, Dyke & Karhu as a member of the Presbyornithidae. These were stilt-legged, Anseriform, waterfowl which are extinct, but which flourished during the Late Cretaceous and Paleogene. If Teviornis does belong to the Presbyornithidae then, together with Vegavis from Antarctica, there is evidence that relatives of today's waterfowl already were widespread and highly apomorphic by the end of the Mesozoic. [2]
Clarke and Norell reviewed the specimen in 2004. They concluded that some of the characters used by Kurochkin et al. to assign T. gobiensis to the Anseriformes, such as an unbowed metacarpal III, are plesiomorphies which are primitive for Avialae and also retained in some members of Ornithurae. They found that the remaining characters used by Kurochkin et al. also had wider distribution than was assumed, or had an incompletely studied distribution. Moreover, Clarke and Norell found no synapomorphies of Aves (sensu Gauthier), Neognathae, or Galloanseres, preserved in PIN 4499–1, so they concluded that Teviornis cannot be confidently assigned to the Presbyornithidae. [3]
In 2016, De Pietri and colleagues reassessed the type specimen of Teviornis and confirmed the taxon's identity as a presbyornithid on the basis of the trochlea carpalis extension (a bony articular process that drives wing extension and flexion), elongate sulcus tendineus, metacarpal synostosis, etc. Certain morphological traits of the type specimen including the facies articularis dimension and the craniocaudally elongated fossa are also found in the other presbyornithids such as Wilaru and Telmabates . Its non-curved carpometacarpus also confirms its identity as an anseriform outside the crown-group. [4] A 2019 study also supports the placement of presbyornithids as stem anseriforms. [5] In 2020, a possible Eocene presbyornithid specimen from Algeria notably showed similarity to Teviornis based on the carpal trochlea extension and the shape of the fossa, reaffirming the taxonomic identity of this taxon as a presbyornithid. [6] A 2023 study placed Teviornis within Presbyornithidae based on phylogenetic analysis. [7]
Tarbosaurus is a genus of large tyrannosaurid dinosaur that lived in Asia during the Late Cretaceous epoch, about 70 million years ago. It contains the single type species: Tarbosaurus bataar, which is known from the Nemegt Formation of Mongolia, with more fragmentary remains found further afield in the Subashi Formation of China. Tarbosaurus is represented by dozens of fossil specimens, including several complete skulls and skeletons. These remains have allowed studies focusing on its phylogeny, skull mechanics, and brain structure. Further fossil remains have been reported from other geologic formations of Asia, however, these remains are fragmentary and can not be confidently assigned to Tarbosaurus or the type species.
Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae, Anseranatidae, and Anatidae, the largest family, which includes over 170 species of waterfowl, among them the ducks, geese, and swans. Most modern species in the order are highly adapted for an aquatic existence at the water surface. With the exception of screamers, males have penises, a trait that has been lost in the Neoaves. Due to their aquatic nature, most species are web-footed.
The stone-curlews, also known as dikkops or thick-knees, consist of 10 species within the family Burhinidae, and are found throughout the tropical and temperate parts of the world, with two or more species occurring in some areas of Africa, Asia, and Australia. Despite the group being classified as waders, most species have a preference for arid or semiarid habitats.
Therizinosaurus is a genus of very large therizinosaurid that lived in Asia during the Late Cretaceous period in what is now the Nemegt Formation around 70 million years ago. It contains a single species, Therizinosaurus cheloniformis. The first remains of Therizinosaurus were found in 1948 by a Mongolian field expedition at the Gobi Desert and later described by Evgeny Maleev in 1954. The genus is only known from a few bones, including gigantic manual unguals, from which it gets its name, and additional findings comprising fore and hindlimb elements that were discovered from the 1960s through the 1980s.
Vegavis is a genus of extinct bird that lived in Antarctica during the Maastrichtian stage of the Late Cretaceous. The type species is Vegavis iaai. Vegavis was initially considered to be a member of Anseriformes within Galloanserae, but this claim has not been supported by some recent studies.
Neognathae is an infraclass of birds, called neognaths, within the class Aves of the clade Archosauria. Neognathae includes the majority of living birds; the exceptions being the tinamous and the flightless ratites, which belong instead to the sister taxon Palaeognathae. There are nearly 10,000 living species of neognaths.
Gobipteryx is a genus of prehistoric bird from the Campanian Age of the Late Cretaceous Period. It is not known to have any direct descendants. Like the rest of the enantiornithes clade, Gobipteryx is thought to have gone extinct near the end of the Cretaceous.
Presbyornis is an extinct genus of presbyornithid bird from North America during the Paleogene period, between the Late Paleocene and Early Eocene.
The Barun Goyot Formation is a geological formation dating to the Late Cretaceous Period. It is located within and is widely represented in the Gobi Desert Basin, in the Ömnögovi Province of Mongolia.
The Nemegt Formation is a geological formation in the Gobi Desert of Mongolia, dating to the Late Cretaceous. The formation consists of river channel sediments and contains fossils of fish, turtles, crocodilians, and a diverse fauna of dinosaurs, including birds.
The Djadochta formation is a highly fossiliferous geological formation in Central Asia, Gobi Desert, dating from the Late Cretaceous period, about 75 million to 71 million years ago. The type locality is the Bayn Dzak locality, famously known as the Flaming Cliffs. Reptile and mammal remains are among the fossils recovered from the formation.
Presbyornithidae is an extinct group of birds found in North America, South America, East Asia, Australia and possibly North Africa. They had evolved by the Maastrichtian age of the Late Cretaceous and became extinct during the Aquitanian age of the Early Miocene. The family contains the oldest known neognath, Teviornis from the Nemegt Formation of Mongolia.
The Pelagornithidae, commonly called pelagornithids, pseudodontorns, bony-toothed birds, false-toothed birds or pseudotooth birds, are a prehistoric family of large seabirds. Their fossil remains have been found all over the world in rocks dating between the Early Paleocene and the Pliocene-Pleistocene boundary.
Gurilynia is a genus of enantiornithine birds. One species is known, G. nessovi. It lived during the Maastrichtian stage of the Late Cretaceous period, between 70 and 66 mya. Gurilynia is known from fragmentary fossils found at the Gurilyn Tsav locality of the Nemegt Formation in south Gobi, Mongolia.
Wilaru is an extinct genus of presbyornithid bird from Australia during the Late Oligocene to Early Miocene, around 26-22 million years ago. The type species is Wilaru tedfordi, and the second species is Wilaru prideauxi.
The Odontoanserae is a proposed clade that includes the family Pelagornithidae and the clade Anserimorphae. The placement of the pseudo-toothed birds in the evolutionary tree of birds has been problematic, with some supporting the placement of them near the orders Procellariformes and Pelecaniformes based on features in the sternum.
Garganornis is an extinct genus of enormous flightless anatid waterfowl from the Late Miocene of Gargano, Italy. The genus contains one species, G. ballmanni, named by Meijer in 2014. Its enormous size is thought to have been an adaptation to living in exposed, open areas with no terrestrial predators, and as a deterrent to the indigenous aerial predators like the eagle Garganoaetus and the giant barn owl Tyto gigantea.
Asteriornis is an extinct genus of bird from the Late Cretaceous of Belgium which is known from a single species, Asteriornis maastrichtensis. It was closely related to birds of the extant superorder Galloanserae such as chickens and ducks. Members of the genus were small, long-legged birds that lived near the coastline and co-existed with more "primitive" types of birds such as Ichthyornis. Asteriornis is one of the oldest-known birds irrefutably belonging to the group Neornithes, which encompasses all modern birds. It possesses characteristics of both galliformes and anseriformes, indicating its position as a close relative of the last common ancestor for both groups.
Ondogurvel is a genus of alvarezsaurid dinosaur from the Late Cretaceous (Campanian) Barun Goyot Formation in southern Mongolia. The type and only species is O. alifanovi, known from a partial skeleton consisting of fragments of two last dorsal vertebrae, three anterior sacral vertebrae, right ilium, left and right pubis and ischium, articulated right tibia, fibula, metatarsals II and IV, and phalanges IV-1 and IV-2, right carpometacarpus, left and right manual phalanx II-1, right femur, left pedal phalanx II-1, and fragments of unidentified phalanges.
Telmabates is an extinct genus of presbyornithid bird from the Eocene Bird Clay Locality of the Sarmiento Formation of Chubut Province, Argentina. The genus contains a single species, T. antiquus.