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''Teviornis'' is a
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of extinct
bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...
s. One species has been described, ''T. gobiensis''. It lived in the
Maastrichtian The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval from ...
stage at the end of the Late
Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...
period, some 70 million years ago. It is known from fossils collected from the
Nemegt Formation The Nemegt Formation (also known as Nemegtskaya Svita) 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, crocodilian ...
of Gobi, south
Mongolia Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, ...
. The fossils include only the
holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...
which are pieces of a crushed right forelimb. These pieces include a nearly complete right
carpometacarpus The carpometacarpus is a bone found in the hands of birds. It results from the fusion of the carpal and metacarpal bone, and is essentially a single fused bone between the wrist and the knuckles. It is a smallish bone in most birds, generally flatt ...
, two phalanges, the
radiale ''Radiale'' is the fifth studio album by Italian band Zu, in collaboration with Spaceways Inc., released in 2004.http://www.sentireascoltare.com/recensione/4741/zu-radiale.html The album received an A grade from The Village Voice and was pl ...
and
ulnare The triquetral bone (; also called triquetrum, pyramidal, three-faced, and formerly cuneiform bone) is located in the wrist on the medial side of the proximal row of the carpus between the lunate and pisiform bones. It is on the ulnar side of the ...
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. The fossils were collected at the Gurilyn tsav locality, northwest corner of Umnogobi Aimak, Mongolia. They are in the collection 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. Gobiensis refers to the harsh
Gobi Desert The Gobi Desert (Chinese: 戈壁 (沙漠), Mongolian: Говь (ᠭᠣᠪᠢ)) () is a large desert or brushland region in East Asia, and is the sixth largest desert in the world. Geography The Gobi measures from southwest to northeast an ...
in which the fossil was found. The fossils are in the collection of the
Paleontological Institute, Russian Academy of Sciences The Paleontological Institute, Russian Academy of Sciences (PIN; russian: Палеонтологический институт РАН) in Moscow is among the world's largest paleontological institutes. An affiliate of the Russian Academy of Scienc ...
, Moscow. ''Teviornis'' was described by Kurochkin, et al.Kurochkin, Evgeny V., Dyke, Gareth J., Karhu, Alexandr A. (2002) "A New Presbyornithid Bird (Aves, Anseriformes) from the Late Cretaceous of Southern Mongolia" "American Museum Novitates" December 27, 2002, Number 3866, 11pp. as a member of the
Presbyornithidae Presbyornithidae is an extinct group of birds with a global distribution. They had evolved by the late Cretaceous period and became extinct during the early Miocene. Initially, they were believed to present a mix of characters shown by waterbirds ...
. These were stilt-legged,
Anseriform Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which inc ...
,
waterfowl Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which in ...
which are
extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
, but which flourished during the
Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...
and
Paleogene The Paleogene ( ; British English, also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period, geologic period and system that spans 43 million years from the end of the Cretaceous Period million yea ...
. If ''Teviornis'' does belong to the Presbyornithidae then, together with ''
Vegavis ''Vegavis'' is a genus of extinct bird that lived during the Late Cretaceous (Maastrichtian stage) of Antarctica, some 68 to 66 mya. Among modern birds, most studies show that ''Vegavis'' is most closely related to ducks and geese (Anatidae), b ...
'' from
Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...
, there is evidence that relatives of today's waterfowl already were widespread and highly
apomorph 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 have ...
ic by the end of the
Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceo ...
. A review of Kurochkin et al. was performed by Clarke and Norell in 2004. They concluded that some of the characters used by Kurochkin et al. to assign ''T. gobiensis'' to the
Anseriformes Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which in ...
, such as an unbowed
metacarpal In human anatomy, the metacarpal bones or metacarpus form the intermediate part of the skeletal hand located between the phalanges of the fingers and the carpal bones of the wrist, which forms the connection to the forearm. The metacarpal bones ...
III, are
plesiomorphies In phylogenetics, a plesiomorphy ("near form") and symplesiomorphy are synonyms for an ancestral character shared by all members of a clade, which does not distinguish the clade from other clades. Plesiomorphy, symplesiomorphy, apomorphy, and ...
which are primitive for
Avialae Avialae ("bird wings") is a clade containing the only living dinosaurs, the birds. It is usually defined as all theropod dinosaurs more closely related to birds (Aves) than to deinonychosaurs, though alternative definitions are occasionally used ...
and also retained in some members of
Ornithurae Ornithurae (meaning "bird tails" in Greek) is a natural group which includes the common ancestor of ''Ichthyornis'', ''Hesperornis'', and all modern birds as well as all other descendants of that common ancestor. Classification Ernst Haeckel coi ...
. 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 et al. found no
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 have ...
of
Aves Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...
(sensu Gauthier),
Neognathae Neognathae (; ) is a 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 ...
, or
Galloanseres Fowl are birds belonging to one of two biological orders, namely the gamefowl or landfowl (Galliformes) and the waterfowl ( Anseriformes). Anatomical and molecular similarities suggest these two groups are close evolutionary relatives; togethe ...
, preserved in PIN 4499-1. thus, they conclude, ''Teviornis'' cannot be assigned with any confidence to the Presbyornithidae.Clarke, Julia A., Norell, Mark A. (2004) "New Avialan Remains and a Review of the Late Cretaceous Nemegt Formation of Mongolia" "American Museum Novitates" Number 3447, 12pp. June 2, 2004


References


External links

* palaeos.com
360.650 Galloanserae: Anseres: Anatoidea: ''Teviornis''
Drawings of type
carpometacarpus The carpometacarpus is a bone found in the hands of birds. It results from the fusion of the carpal and metacarpal bone, and is essentially a single fused bone between the wrist and the knuckles. It is a smallish bone in most birds, generally flatt ...
and
humerus The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...
. Version of 2004-JUL-13. Retrieved 2007-NOV-08. {{Taxonbar, from=Q2297131 Fossil taxa described in 2002 Late Cretaceous birds of Asia Nemegt fauna Presbyornithidae