ornithomimidae

Struthiomimus altus, S. sedens

Source: http://green-mamba.deviantart.com/art/018-STRUTHIOMIMUS-ALTUS-287776180

Name: Struthiomimus altus, S. sedens

Name Meaning: Ostrich Mimic

First Described: 1917

Described By: Osborn

ClassificationDinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoriformes, Ornithomimosauria, Ornithomimidae, Ornithomiminae

Struthiomimus is, arguably, the best known ornithomimosaur, and the most famous. It is known from many individuals and lived primarily in the USA and Canada. S. altus is known mainly from the Dinosaur Park Formation in Alberta, Canada, dating back to the Campanian age of the Late Cretaceous, about 75 million years ago. S. sedens is known from the Lance and Hell Creek Formations in the United States, dating to the Maastrichtian age of the Late Cretaceous, about 66 million years ago. Finally, a third species which has not yet been named was found in the Horseshoe Canyon Formation in Canada, dating to 70 million years ago in the early Maastrichtian age of the Late Cretaceous. This third species differed from the other two in having more slender hands. S. sedens was the largest of the three, similar in size to Gallimimus, about 5 meters long. S. altus was about 4.3 meters long. 

Source: http://haghani.deviantart.com/art/Tyrannosaurus-rex-VS-Struthiomimus-353106129

Struthiomimus was actually one of the first theropods imagined with a horizontal posture that we think of them in today, rather than the vertical one common to many early examples of palaeoart. It had a keratinous, toothless beak that could have been used for a variety of feeding strategies. It could have been used to selectively browse in trees, or to pick out grubs and insects, or to better grab small reptiles and animals. It also could have been a filter feeder. The modern consensus seems to be that it was an omnivore. Its hands could have functioned at hooks or clamps, sort of like the hands of sloths, to bring branches and ferns within reach. It had powerful, well structured legs, allowing it to run away from predators at speeds between 50 and 80 km/h (31 and 50 mph). And it needed this speed - it lived alongside large tyrannosaurs such as Albertosaurus and Tyrannosaurus, and dromaeosaurs like Dromaeosaurus, as well as many herbivores such as Chasmosaurus, Euoplocephalus, and Edmontosaurus. 

Sources: 

http://www.prehistoric-wildlife.com/species/s/struthiomimus.html

http://en.wikipedia.org/wiki/Struthiomimus

Shout out goes to kam336!

Anserimimus planinychus

Source: http://dinosaurs.wikia.com/wiki/Anserimimus

Name: Anserimimus planinychus

Name Meaning: Goose Mimic

First Described: 1988

Described By: Barsbold 

ClassificationDinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoriformes, Ornithomimosauria, Ornithomimidae, Ornithomiminae 

Anserimimus is a more advanced ornithomimid dinosaur from the Nemegt Formation in Bayankhonger Province, Mongolia. Anserimimus lived in the early Maastrichtian age of the Late Cretaceous, about 70 million years ago. It was a relatively small ornithomimid, only about 3 meters long. Even though Anserimimus does not specifically resemble geese, ornithomimosaurs have long been named for different species of birds. It is known from only one skeleton, making it relatively unknown. It was very closely related to Gallimimus. It lived alongside Tarbosaurus, Deinocheirus, Barsboldia, Saurolophus, Tarchia, dromaeosaurids, oviraptorosaurs, troodontids, birds, titanosaurs, and pachycephalosaurians. It lived amongst stream and river channels, mudflats, and shallow lakes. It was probably an omnivore and is distinguished from other ornithomimosaurs by its extremely powerful arms and almost straight claws. What the arms were for is still unknown. 

Sources:

http://www.prehistoric-wildlife.com/species/a/anserimimus.html

http://en.wikipedia.org/wiki/Anserimimus

Shout out goes to jagannaths!

Gallimimus bullatus

By Henry Thomas on @raptorcivilization

Name: Gallimimus bullatus 

Name Meaning: Chicken Mimic

First Described: 1972

Described By: Osmólska, Roniewics & Barsbold 

ClassificationDinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoriformes, Ornithomimosauria, Ornithomimidae, Ornithomiminae

Gallimimus is a fairly famous ornithomimosaur simply by virtue of it being in the Jurassic Park franchise. Even though it was found running away from Tyrannosaurus in the film, its not too far off the mark: Gallimimus lived alongside T. rex’s similar cousin, Tarbosaurus.  We do know a reasonable amount about the dinosaur, though, as it is known from numerous individuals, as well as some juveniles. It was one of the largest members of its family, reaching up to 8 meters long and four meters high. It was found in the Nemegt Formation in Mongolia, and lived in the Maastrichtian age of the Late Cretaceous, about 70 million years ago. It was extremely ostrich like in appearance, much like the other members of its family. It had very short hands compared to its arms, unique to it as opposed to other ornithomimosaurs. It had hollow bones and very thin jaw bones. It had long, powerful legs, good for running away from predators. 

Source: http://phenomena.nationalgeographic.com/2013/12/16/feathers-for-tyrannosaurs/

Gallimimus, like other members of its family, was probably an omnivore, though the definitive dietary status of the group is still under debate. It had structures in its beak much like that of ducks, which would be used to strain small bits of food form the water. But these structures in the beak also resemble surfaces in the beaks of herbivorous turtles, indicating that rather than being filter-feeders, Gallimimus and kin were strictly herbivorous. More fossils will need to be found to better understand the dietary habits of these animals. It was a relatively basal ornithomimosaur, no where near as derived as Struthiomimus or Ornithomimus, two other famous members of the group. Besides Tarbosaurus, this animal lived alongside other large dinosaurs such as Gigantoraptor. 

Sources: 

http://www.prehistoric-wildlife.com/species/g/gallimimus.html

http://en.wikipedia.org/wiki/Gallimimus


Shout out goes to angelofdisease!