dilophosauridae

DRACOVENATOR
“Dragon hunter”
Early Jurassic, 201-199 million years ago

This early Jurassic predator was a relative of Dilophosaurus and may have had a similar crest, but fossil evidence is sparse. It was found near Drakensburg, South Africa (“Dragon’s Mountain” in Dutch), and was given the name “dragon hunter” because it subsisted primarily on dragons. It is thought to have died out, as its main food source was imaginary.

Dilophosaurus wetherilli

By Sam Stanton on @artisticthingem

NameDilophosaurus wetherilli

Name Meaning: Two crested lizard

First Described1954

Described By: Welles 

ClassificationDinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Dilophosauridae 

Dilophosaurus is a fairly well known - and fairly misunderstood - early theropod dinosaur. It lived around 193 million years ago in the Sinemurian stage of the early Jurassic Period. At first it was named a species of Megalosaurus, however upon the discovery of a second specimen in which the crest was clearly visible it was renamed Dilophosaurus. The fossil evidence of Dilophosaurus indicate that the fossils found are probably from subadult individuals. It was discovered in the Kayenta Formation in Arizona. Dilophosaurus was a bipedal predator, and was probably a fast and agile runner. As several individuals were found together as fossils, there is some evidence that Dilophosaurus might have lived in social groups (however, this could have been attributed to other reasons as well, such as all having been swept away together in a flash flood.) It probably lived near river environments, allowing it to prey on a variety of organisms. It lived in the same environment as many other early dinosaurs, such as Megapnosaurus, Kayentavenator, Sarahsaurus, Scelidosaurus, and Scutellosaurus. It also lived in the same environment as the pterosaur Rhamphinion. Dilophosaurus remains have also been found in the Dharmaram Formation in Andhra Pradesh, India. This specimen shared its environment with a crocodilian, a sauropodomorph, and Lamplughsaura


By Fraizer on @saint-nevermore

Dilophosaurus was a large predator, around seven meters long, and around the height of a person. It had a pair of rounded crests on its skull, which were most definitely used for display. A notch in its upper jawline allowed for Dilophosaurus to have an almost crocodile like mouth, similar to the later Spinosaurid dinosaurs. This could indicate that Dilophosaurus would occasionally prey on fish as well as terrestrial animals. There is no indication of sexual dimorphism in the species. The crest could have been used for attracting mates or intimidating other members of the social group, or it could have been used to distinguish separate species from one another. It grew rapidly, according to the bone structure. Trackways have been found that are attributed to Dilophosaurus, or at least a similar species, in Arizona, Poland, Sweden, Massachusetts, and Connecticut. Furthermore, trackways in Massachusetts also have what appear to be feather imprints alongside the footprints, suggesting that Dilophosaurus - a still very early theropod - had feathers! (Or at least, a very early form of feathers). This would indicate that the evolution of feathers started very early in the dinosaur family tree, allowing for Archaeopteryx to be a real contender for one of the earliest birds.

By Leandra Walters, Phil Senter, James H. Robins, CC BY 2.5, from Wikipedia

Dilophosaurus is very well known in popular culture due to the Jurassic Park franchise. However, the film (and the book) got Dilophosaurus quite wrong. Dilophosaurus was, to begin with, much larger than the film DilophosaurusDilophosaurus in the film was made much smaller than usual so as not to be confused with the Velociraptor. However, Velociraptor in real life was much smaller than in Jurassic Park, and Dilophosaurus was bigger. Furthermore, there is no fossil evidence that Dilophosaurus supported a neck frill, or that it could spit venom. However, many further pop culture depictions of dinosaurs depict Dilophosaurus with these features, creating a large misrepresentation of the animal, which is rather unfortunate. 

Sources: 

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

Weishampel, D. B. (2007). The Dinosauria (2nd ed.). Berkeley, Calif.: University of California Press.

Dixon, D. (2007). The Complete Book of Dinosaurs. London, England: Anness Publishing.

Shout out goes to icedteawithstrawberries! 

SINOSAURUS
“Chinese lizard”
Early Jurassic, 201-196 million years ago

Related to Dilophosaurus of Jurassic Park fame, Sinosaurus had two crests on its snout and powerful, curving jaws. It lived during the Jurassic period in what is now China. The first species found, Sinosaurus triassicus, was mistakenly dated to the Triassic, prompting Sinosaurus to avoid questions about its age for a very long time. Some recent finds are interpreted as showing evidence of facelifts.

Neotheropoda

Source: http://www.sciencemag.org/news/2014/10/new-meat-eating-dinosaur-lived-wake-mass-extinction

Group: Neotheropoda

Classification: Cellular Life, Archaea, Proteoarchaeota, Eukaryota, Unikota, Opisthokonta, Holozoa, Filozoa, Metazoa, Eumetazoa, Planulozoa, Bilatera, Nephrozoa, Deuterostomia, Chordata, Craniata, Vertebrata, Gnathostomata, Eugnathostomata, Teleostomi, Euteleostomi, Sarcopterygii, Rhipidistia, Tetrapodomorpha, Eotetrapodiforms, Elpistostegalia, Stegocephalia, Tetrapoda, Reptiliomorpha, Anthracosauria, Batrachosauria, Cotylosauria, Amniota, Sauropsida, Eureptilia, Romeriida, Diapsida, Neodiapsida, Sauria, Archosauromorpha, Archelosauria, Archosauriformes, Crurotarsi, Archosauria, Avemetatarsalia, Ornithodira, Dinosauromorpha, Dinosauriformes, Dinosauria, Saurischia, Eusaurischia, Theropoda 

Definition: The group including the most recent common ancestor of Ceolophysis and modern birds, and all of that animal’s descendants 

Organisms Within: Zupaysaurus, Tachiraptor, Dilophosauridae (not examined here), Coelophysoidea (not examined here), Averostra (not examined here), & two miscellaneous genera without further placement. 

Time Range: Shown below, numbers on the left in millions of years. Though the only basal Neotheropods known are from the Triassic-Jurassic boundary, members of other groups are present much earlier than that, about 220 million years ago, implying that they must have evolved at around that time or older.  

Characteristics

Neotheropods differ from basal theropods mainly on a few skeletal points. The ilium bone in the pelvis, expanded towards the top of the animal (dorsally).  The snout is more narrow than in basal theropods, there are more vertebrae fused to the hips, there is a complete loss of the fifth digit of the foot (as shown below), and a general stiffening of the legs overall. 

By @ewilloughby

Like all early dinosaurs, Neotheropods were probably covered in a layer of primitive feathers - though some theropods groups would later lose feathers, the general line leading up to birds must have kept them, given that birds have feathers. They were bipedal, fast predators, and basal members of Neotheropoda were probably outcompeted by later animals, and even during their existence Coelophysoids were far more common. 

Source: @alphynix

Fossil Locations: It is fairly likely that Neotheropods also originated in Argentina, during that very rapid early diversification of dinosaurs in the region. This assessment is based mainly on the presence of basal theropods mainly in the region, though its possible that it also occurred in North America, where many Coelophysoids lived. Coelophysoids have also been found in Europe and Asia, and so given this widespread range of this group and its early evolution, as well as the locations of basal theropods, its reasonable to suppose that Argentina is where they started, unless evidence to the contrary comes to light.

Biogeography: Neotheropods spread throughout the globe, as described above; this was relatively easy due to Panagaea, however, most Coelophysoids congregated around North America and Europe. The two basal members of the group stayed in South America. Maps from Dr. Christopher Scotese. 

Read more about Zupaysaurus here!

Read more about Tachiraptor here! 

Read more about Coelophysoidea here!

Posts on Dilophosauridae and Averostra to come soon!

Sources: 

https://en.wikipedia.org/wiki/Neotheropoda

http://palaeos.com/vertebrates/theropoda/neotheropoda.html

https://en.wikipedia.org/wiki/Zupaysaurus

https://en.wikipedia.org/wiki/Tachiraptor

Shout out goes to @chequitablr!

Miscellaneous Neotheropods not examined here that do not have further placement (links added as I do posts on them): 

Altispinax

Szechuanosaurus