Tenontosaurus‭ (‬Sinew lizard‭)‬

Short Info

Tenontosaurus‭ (‬Sinew lizard‭)‬

Phonetic : Te-non-to-sore-us

Named By : John Ostrom‭ ‬-‭ ‬1970

Diet : Herbivore

Size : Estimated 6.5‭ ‬- ‬8 meters long

Type of Dinosaur : Euornithopod

Type Species : T.‭ ‬tiletti‭ (‬type‭)‬,‭ ‬T.dossi

Found in : Canada, USA

When it Lived : Early Cretaceous, 120-110 million years ago

Tenontosaurus (/tI,nant@’so:r@sor ti-NON’SOR-@s, which translates to “sinew lizard”) is an genus that is mediumto large-sized ornithopod dinosaurs. The genus is recognized as of the Aptian to Albian age range from the Early Cretaceous period sediments of western North America, dating between 120 and 108 million years ago.


Perot Museum TenontosaurusRodney, CC BY 2.0, via Wikimedia Commons


The genus is home to two species: Tenontosaurus tilletti (described by John Ostrom in 1970[1]) and Tenontosaurus dossi (described by Winkler, Murry, and Jacobs in 1997). A large number of examples from T. tilletti have been found in various geological formations in the western part of North America. T. dossi is known from a small number of specimens from the Twin Mountains Formation of Parker County, Texas.

It was 6.5 up to eight metres (21 to 26 feet) long , and three meters (10 feet) tall in an upright bipedal posture, and had an estimated weight of 1 and 2 tonnes (1 up to two short tonnes). It had a broad, long tail that, like its back, was stiffened by a network of bony tendon.

The first fossil of Tenontosaurus was discovered at Big Horn County, Montana by an American Museum of Natural History (AMNH) expedition in 1903. Further excavations in the same region in the 1930s revealed 18 more fossils and four specimens were discovered in the 1940s. Despite the abundance of fossils found however, the animal was not scientifically identified at this period, even though Barnum Brown of the AMNH has given it the informal name “Tenantosaurus”, “sinew lizard” in reference to the vast system of stiffening tendons on its tail and back.

In the early 1970s Yale University began an extensive, long-term excavation throughout the Big Horn Basin area (Cloverly Formation) of Montana and Wyoming. The team was headed by John Ostrom, whose team found more than 40 new specimens. In the wake of his trip, Ostrom became the first to identify and name the animal, naming it Tenontosaurus which is a slight change in spelling from Brown’s formal name.

Since 1970, numerous more Tenontosaurus species have been identified and come from the Cloverly and from other formations, such as those from the Antlers Formation in Oklahoma, Paluxy Formation of Texas, Wayan Formation of Idaho, Cedar Mountain Formation of Utah and the Arundel Formation of Maryland.

Source: Wikipedia