Panphagia
Encyclopedia
Panphagia is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of sauropodomorph
Sauropodomorpha
Sauropodomorpha is an extinct clade of long-necked, herbivorous, saurischian dinosaurs which includes the sauropods and their ancestral relatives. Sauropods generally grew to very large sizes, had long necks and tails, were quadrupedal, and became the largest animals to ever walk the Earth. The...

 dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

 described in 2009. It lived 231 million years ago, during the late Ladinian
Ladinian
The Ladinian is a stage and age in the Middle Triassic series or epoch. It spans the time between 237 ± 2 Ma and 228 ± 2 Ma...

 age of the mid Triassic period (according to the ICS
International Commission on Stratigraphy
The International Commission on Stratigraphy , sometimes referred to by the unofficial "International Stratigraphic Commission" is a daughter or major subcommittee grade scientific daughter organization that concerns itself with stratigraphy, geological, and geochronological matters on a global...

; alternately the early Carnian
Carnian
The Carnian is the lowermost stage of the Upper Triassic series . It lasted from about 228.7 till 216.5 million years ago . The Carnian is preceded by the Ladinian and is followed by the Norian...

 age of the Late Triassic
Late Triassic
The Late Triassic is in the geologic timescale the third and final of three epochs of the Triassic period. The corresponding series is known as the Upper Triassic. In the past it was sometimes called the Keuper, after a German lithostratigraphic group that has a roughly corresponding age...

 in the system used by the Geological Society of America
Geological Society of America
The Geological Society of America is a nonprofit organization dedicated to the advancement of the geosciences. The society was founded in New York in 1888 by Alexander Winchell, John J. Stevenson, Charles H. Hitchcock, John R. Proctor and Edward Orton and has been headquartered at 3300 Penrose...

), in what is now northwestern Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

. The name Panphagia comes from the Greek words pan, meaning "all", and phagein, meaning "to eat", in reference to its inferred omnivorous diet. Panphagia is one of the earliest known dinosaurs, and is an important find which may mark the transition of diet in early sauropodomorph dinosaurs.

Discovery

Fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

s of Panphagia were found in late 2006 by the Argentinean paleontologist Ricardo N. Martínez in rocks of the Ischigualasto Formation of Valle Pintado, Ischigualasto Provincial Park, San Juan Province
San Juan Province (Argentina)
San Juan is a province of Argentina, located in the western part of the country. Neighbouring provinces are, moving clockwise from the north, La Rioja, San Luis and Mendoza. It borders with Chile at the west....

, Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

. The bones were found at approximately the same level as a 231.4 million year old ash layer, indicating it lived during the early Carnian
Carnian
The Carnian is the lowermost stage of the Upper Triassic series . It lasted from about 228.7 till 216.5 million years ago . The Carnian is preceded by the Ladinian and is followed by the Norian...

 of the Late Triassic
Late Triassic
The Late Triassic is in the geologic timescale the third and final of three epochs of the Triassic period. The corresponding series is known as the Upper Triassic. In the past it was sometimes called the Keuper, after a German lithostratigraphic group that has a roughly corresponding age...

. Panphagia is currently known from holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

 PVSJ 874, the disarticulated remains of one partially-grown individual of about 1.3 metres (4.3 ft) long. Portions of the skull, vertebrae, pectoral girdle, pelvic girdle
Pelvis
In human anatomy, the pelvis is the lower part of the trunk, between the abdomen and the lower limbs .The pelvis includes several structures:...

, and hindlimb bones have been recovered. The russet-colored fossils were embedded in a greenish sandstone matrix and took several years to prepare and describe.

Classification

{clade|style=font-size:75% label1= Saurischia
Saurischia
Saurischia meaning 'lizard' and ischion meaning 'hip joint') is one of the two orders, or basic divisions, of dinosaurs. In 1888, Harry Seeley classified dinosaurs into two orders, based on their hip structure...

 
1=
}}
Basal saurischian phylogeny simplified after Martinez and Alcober, 2009. This is only one of many proposed cladograms for basal saurischians.

Panphagia was described in 2009 by Ricardo N. Martínez and Oscar A. Alcober, both of the Museo de Ciencias Naturales, in San Juan, Argentina. They performed a phylogenetic analysis
Cladistics
Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

 and found it to be the most basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...

 known sauropodomorph dinosaur: the fossils shared similar features to those of Saturnalia
Saturnalia (dinosaur)
Saturnalia is an extinct genus of basal sauropodomorph dinosaur known from the Triassic of Rio Grande do Sul, southern Brazil.-Discovery:Saturnalia was originally named on the basis of three partial skeletons...

, an early sauropodomorph, including similarities in the ischium, astralagus, and the scapular blade. Yet the fossils also exhibited similar features to those of Eoraptor
Eoraptor
Eoraptor was one of the world's earliest dinosaurs. It was a two-legged saurischian, close to the ancestry of theropods and sauropodomorphs. It lived ca. 231.4 million years ago, in what is now the northwestern region of Argentina...

, an early carnivorous saurischian, including hollow bones, sublanceolate teeth, and overall proportions. Based on analysis and comparison of the Panphagia fossils and those of its closest kin, Martínez and Alcober concluded that the evolution of saurischian dinosaurs likely began with small, cursorial animals similar to Panphagia, and that there is a "general similarity among all of these basal dinosaurs [suggesting] that few structural changes stand" between Panphagia, Eoraptor, and two basal theropods which have yet to be described.

The type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

 of Panphagia is P. protos; the specific name, meaning "the first" in Greek, is a reference to its basal position.

Diet

The teeth of Panphagia indicate a possible omnivorous diet, transitional in form between the mostly carnivorous theropods and the herbivorous sauropodomorphs. The teeth in the back of the jaw are shorter than those in the front, are leaf-shaped, and also have more marked serrations.
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