Tehuelchesaurus 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 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...

. It is named in honor of the Tehuelche people native to the Argentinian province

Provinces of Argentina

Argentina is subdivided into twenty-three provinces and one autonomous city...

 of Chubut

Chubut Province

Chubut a province in the southern part of Argentina situated between the 42nd parallel south and the 46th parallel south , the Andes range separating Argentina from Chile, and the Atlantic ocean...

, where it was first found.

It was a moderately large (?15 m long) cetiosaur-like sauropod found in the Middle Jurassic

Middle Jurassic

The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from 176-161 million years ago. In European lithostratigraphy, rocks of this Middle Jurassic age are called the Dogger....

 (?Callovian) Cañadon Asfalto Formation at Fernandez Estancia, Chubut Province, Patagonia

Patagonia

Patagonia is a region located in Argentina and Chile, integrating the southernmost section of the Andes mountains to the southwest towards the Pacific ocean and from the east of the cordillera to the valleys it follows south through Colorado River towards Carmen de Patagones in the Atlantic Ocean...

, 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...

; known from a 50% complete skeleton (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...

: MPEF-PV 1125 (Museo Paleontologico Egidio Fergulio)), lacking a skull, but including dorsal

Dorsum (biology)

In anatomy, the dorsum is the upper side of animals that typically run, fly, or swim in a horizontal position, and the back side of animals that walk upright. In vertebrates the dorsum contains the backbone. The term dorsal refers to anatomical structures that are either situated toward or grow...

, sacral

Sacrum

In vertebrate anatomy the sacrum is a large, triangular bone at the base of the spine and at the upper and back part of the pelvic cavity, where it is inserted like a wedge between the two hip bones. Its upper part connects with the last lumbar vertebra, and bottom part with the coccyx...

 and caudal vertebrae, parts of the forelimbs and hindlimbs, parts of the shoulder girdle and pelvis

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:...

, some rib fragments, and skin impressions.

Tehuelchesaurus is most similar to Omeisaurus

Omeisaurus

Omeisaurus is a genus of sauropod dinosaur from the Middle Jurassic Period of what is now China. Its name comes from Mount Emei, where it was discovered in the lower Shaximiao Formation of Sichuan Province.Like other sauropods, Omeisaurus was herbivorous and large...

from the Middle Jurassic of China

China

Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

, but is distinguished by the shape of the coracoid, the stouter radius

Radius (bone)

The radius is one of the two large bones of the forearm, the other being the ulna. It extends from the lateral side of the elbow to the thumb side of the wrist and runs parallel to the ulna, which exceeds it in length and size. It is a long bone, prism-shaped and slightly curved longitudinally...

 and ulna

Ulna

The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form and runs parallel to the radius, which is shorter and smaller. In anatomical position The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form...

, and the shapes of the pubis

Pubis (bone)

In vertebrates, the pubic bone is the ventral and anterior of the three principal bones composing either half of the pelvis.It is covered by a layer of fat, which is covered by the mons pubis....

 and ischium; all the dorsal vertebrae have pseudopleurocoels (deep depressions in the centra but without internal chambers) and opisthocoelous centra, unlike in Barapasaurus

Barapasaurus

Barapasaurus is a genus of sauropod dinosaur from Early Jurassic rocks of India. The specific name for its only species, B. tagorei, means 'Tagore's', which honors Bengali poet, writer, painter, and musician Rabindranath Tagore.-Description:...

and Patagosaurus

Patagosaurus

Patagosaurus was a large herbivorous dinosaur from the long-necked group Sauropoda. It reached a length of 18 meters. Similar to other primitive eusauropods, it was rather heavily built and similar to Cetiosaurus in general appearance. It is known from a dozen individuals, though some referred...

. The length of the entire neck and tail are not known, but based on other proportions (humerus

Humerus

The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....

 1.14 m long; femur 1.53 m long; scapula

Scapula

In anatomy, the scapula , omo, or shoulder blade, is the bone that connects the humerus with the clavicle ....

 1.75 m long; ischium 1.01 m long; ilium

Ilium (bone)

The ilium is the uppermost and largest bone of the pelvis, and appears in most vertebrates including mammals and birds, but not bony fish. All reptiles have an ilium except snakes, although some snake species have a tiny bone which is considered to be an ilium.The name comes from the Latin ,...

 1.12 m; pubis .943 m long), Tehuelchesaurus was probably about 15 m (50 ft) long. It was discovered by Rich, Vickers-Rich, Gimenez, Cuneo, Puerta & Vacca in 1999.

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...

: Tehuelchesaurus benitezii [bay-nee-TAY-see-ie] Rich, Vickers-Rich, Gimenez, Cuneo, Puerta & Vacca: for Aldo Benitez, who discovered the holotype.

External links

• Dinosauria Translation and Pronunciation Guide