''Eucnemesaurus'' (; meaning "good tibia lizard", for its robust

tibia The tibia (; ), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outside of the tibia); it conn ...

e) is a basal sauropodomorph

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

usually considered to be a synonym of '' Euskelosaurus''. Recent study by Yates (2006), however, indicates that it is valid and the same animal as putative "giant herrerasaurid" ''Aliwalia''. ''Eucnemesaurus'' was named in 1920 by

Egbert Cornelis Nicolaas van Hoepen Egbert Cornelis Nicolaas van Hoepen (10 November 1884 – 2 May 1966) was a Dutch-born South African paleontologist. Biography Born at Vlissingen, around the age of six he moved with his parents to the South African Republic. When British for ...

. The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specim ...

is ''Eucnemesaurus fortis''. The specific name means "strong" in

Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through ...

. It is based on

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 seve ...

TrM 119, a partial skeleton including

vertebrae The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristi ...

, part of a pubis, a

femur The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates ...

, and two

e. The remains were found by Van Hoepen in the late Carnian- early Norian-age

Upper Triassic The Late Triassic is the third and final epoch of the Triassic Period in the geologic time scale, spanning the time between Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch. ...

Lower Elliot Formation The Elliot Formation is a geological formation and forms part of the Stormberg Group, the uppermost geological group that comprises the greater Karoo Supergroup. Outcrops of the Elliot Formation have been found in the northern Eastern Cape, sout ...

of the Slabberts district,

Orange Free State The Orange Free State ( nl, Oranje Vrijstaat; af, Oranje-Vrystaat;) was an independent Boer sovereign republic under British suzerainty in Southern Africa during the second half of the 19th century, which ceased to exist after it was defeat ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring coun ...

. Yates assigned the genus to the new family Riojasauridae, with ''

Riojasaurus ''Riojasaurus'' (meaning "Rioja lizard") was a herbivorous sauropodomorph dinosaur named after La Rioja Province in Argentina where it was found in the Los Colorados Formation in the Ischigualasto-Villa Unión Basin by José Bonaparte. It li ...

'', usually regarded as a melanorosaurid.

''Aliwalia''

Fossil material now assigned to ''Eucnemesaurus'' was once placed in a separate genus and

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

, ''Aliwalia rex'' (the

generic Generic or generics may refer to: In business * Generic term, a common name used for a range or class of similar things not protected by trademark * Generic brand, a brand for a product that does not have an associated brand or trademark, other ...

name was taken from the Aliwal Park Reserve in the

Union of South Africa The Union of South Africa ( nl, Unie van Zuid-Afrika; af, Unie van Suid-Afrika; ) was the historical predecessor to the present-day Republic of South Africa. It came into existence on 31 May 1910 with the unification of the Cape, Natal, Tr ...

, where the first remains were found). The

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

evidence of this species was comparably small, with for many years only

femora The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with t ...

l fragments and a

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. T ...

known, having been sent from South Africa to

Austria Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...

in 1873 in a shipment with prosauropod bones. The size of the femur led many

palaeontologist Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of foss ...

s to believe (along with the clearly carnivorous maxilla), that ''Aliwalia'' was a

carnivorous A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other ...

dinosaur of remarkable size for the age in which lived. It would have been comparable to that of the large

Jurassic The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...

and

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 ...

theropods Theropoda (; ), whose members are known as theropods, is a dinosaur clade that is characterized by hollow bones and three toes and claws on each limb. Theropods are generally classed as a group of saurischian dinosaurs. They were ancestrally ca ...

, such as ''

Allosaurus ''Allosaurus'' () is a genus of large carnosaurian theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic epoch ( Kimmeridgian to late Tithonian). The name "''Allosaurus''" means "different lizard" alludin ...

'', that evolved tens of millions of years after ''Aliwalia''. The original material was believed to bear a strong similarity to the

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sou ...

n ''

Herrerasaurus ''Herrerasaurus'' is a genus of saurischian dinosaur from the Late Triassic period. This genus was one of the earliest dinosaurs from the fossil record. Its name means "Herrera's lizard", after the rancher who discovered the first specimen i ...

'', so much so that ''Aliwalia'' was originally classified in

Herrerasauridae Herrerasauridae is a family of carnivorous dinosaurs, possibly basal to either theropods or even all of saurischians, or even their own branching from dracohors, separate from dinosauria altogether. They are among the oldest known dinosaurs, ...

Peter Galton Peter Malcolm Galton (born 14 March 1942 in London) is a British vertebrate paleontologist who has to date written or co-written about 190 papers in scientific journals or chapters in paleontology textbooks, especially on ornithischian and prosa ...

. However, later re-evaluation of the material has shown that the maxilla assigned to ''Aliwalia'' does not, unlike the other material, belong to ''Eucnemesaurus'', as it is clearly from a carnivore. In addition, new material clearly demonstrates this latter genus' sauropodomorph affinities.

Sources

*E. C. N. van Hoepen (1920).
Contributions to the knowledge of the reptiles of the Karroo Formation. 6. Further dinosaurian material in the Transvaal Museum
, ''Annals of the Transvaal Museum'' 7(2): 93-141 * Yates, A.M. (2006). "Solving a dinosaurian puzzle: the identity of ''Aliwalia rex'' Galton". ''Historical Biology'', 1–31

References

{{Taxonbar, from=Q133173 Sauropodomorphs Carnian genera Norian genera Late Triassic dinosaurs of Africa Triassic South Africa Fossils of South Africa Fossil taxa described in 1920 Taxa named by Egbert Cornelis Nicolaas van Hoepen