Zephyrosaurus

Zephyrosaurus (meaning "westward wind lizard") is a genus of orodromine ornithischian dinosaur. It is based on a partial skull and postcranial fragments discovered in the Aptian-Albian-age Lower Cretaceous Cloverly Formation of Carbon County, Montana, USA. New remains are under description, and tracks from Maryland and Virginia, also in the USA, have been attributed to animals similar to Zephyrosarus.

Zephyrosaurus
Temporal range: Early Cretaceous, Aptian–Albian
Deinonychus (Raptor Prey Restraint)
Restoration of Zephyrosaurus being attacked by a Deinonychus
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Order: Ornithischia
Family: Parksosauridae
Subfamily: Orodrominae
Genus: Zephyrosaurus
Sues, 1980
Type species
Zephyrosaurus schaffi

Description

Zephyrosaurus is still very incompletely known. Among other distinctive characteristics, it had a steep face, a raised knob on the upper jaw, and a larger knob on the cheekbone. Some of the bones may have allowed movement within the skull (cranial kinesis) as well. Like other orodromins, it had beak teeth.[1]

Classification

Several studies have suggested that Zephyrosaurus and Orodromeus are closely related, mostly by virtue of both having bosses on their cheeks.[2][3] Other studies have had difficulty classifying it, due to the sparseness of the original material.[4] Oryctodromeus also shares several characteristics with Zephyrosaurus and Orodromeus, some of which may be related to burrowing. Phylogenetic analysis in the 2010s has classified Zephyrosaurus as part of the Thescelosauridae family.

Discovery and history

Hans-Dieter Sues named his new genus in recognition of the fossil being found in western North America, and Charles R. Schaff, who found the specimen. MCZ 4392, the type specimen, is composed of jaw fragments, the braincase and associated bones, several partial vertebrae, and rib fragments. He found the new genus to represent a previously unknown lineage of hypsilophodont (a taxon now considered not natural), similar in some respects to Hypsilophodon.[1]

Because of the fragmentary nature of the type, and lack of additional remains, Zephyrosaurus had not attracted much attention until recently, when two separate events brought it more recognition. First, Martha Kutter, in a 2003 abstract, reported on new remains of this genus under study at the Sam Noble Oklahoma Museum of Natural History, including the remains of at least seven individuals with bones from all regions of the body.[5]

Then, Stanford et al. (2004) published on dinosaur tracks from the Patuxent Formation of Maryland and Virginia, which they named Hypsiloichnus marylandicus and attributed to an animal akin to Zephyrosaurus based on the proportions of the hands and feet.[6]

Paleobiology

Zephyrosaurus would have been a small, swift, bipedal herbivore.[4] Like Orodromeus and Oryctodromeus, it may have burrowed as well.[7]

References

  1. ^ a b Sues, Hans-Dieter (1980). "Anatomy and relationships of a new hypsilophodontid dinosaur from the Lower Cretaceous of North America". Palaeontographica Abteilung a Palaeozoologie-Stratigraphie. 169 (1–3): 51–72.
  2. ^ Weishampel, David B.; Heinrich, Ronald E. (1992). "Systematics of Hypsilophodontidae and Basal Iguanodontia (Dinosauria: Ornithopoda)" (PDF). Historical Biology. 6 (3): 159–184. doi:10.1080/10292389209380426. Retrieved 2007-03-10.
  3. ^ Buchholz, Peter W. (2002). "Phylogeny and biogeography of basal Ornithischia". The Mesozoic in Wyoming, Tate 2002. Casper, Wyoming: The Geological Museum, Casper College. pp. 18–34.
  4. ^ a b Norman, David B.; Sues, Hans-Dieter; Witmer, Larry M.; Coria, Rodolfo A. (2004). "Basal Ornithopoda". In Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (eds.). The Dinosauria (2nd ed.). Berkeley: University of California Press. pp. 393–412. ISBN 0-520-24209-2.
  5. ^ Kutter, M.M. (2003). "New material of Zephyrosaurus schaffi (Dinosauria:Ornithischia) from the Cloverly Formation (Aptian-Albian) of Montana". Journal of Vertebrate Paleontology. 23 (3, Suppl.): 69A. doi:10.1080/02724634.2003.10010538.
  6. ^ Stanford, R.; Weems, R.; Lockley, M. (2004). "A new dinosaur ichnotaxon from the Lower Cretaceous Patuxent Formation of Maryland and Virginia". Ichnos. 11 (3–4): 251–259. doi:10.1080/10420940490428797.
  7. ^ Varricchio, David J.; Martin, Anthony J.; Katsura, Yoshihiro (2007). "First trace and body fossil evidence of a burrowing, denning dinosaur" (PDF). Proceedings of the Royal Society B: Biological Sciences. 274 (1616): 1361–1368. doi:10.1098/rspb.2006.0443. PMC 2176205. PMID 17374596. Retrieved 2007-03-22.

External links

Albertadromeus

Albertadromeus is an extinct genus of orodromine parksosaurid dinosaur known from the upper part of the Late Cretaceous Oldman Formation (middle Campanian stage) of Alberta, Canada. It contains a single species, Albertadromeus syntarsus.

Averostra

Averostra, or "bird snouts", is a clade that includes most theropod dinosaurs that have a promaxillary fenestra (fenestra promaxillaris), an extra opening in the front outer side of the maxilla, the bone that makes up the upper jaw. Two groups of averostrans, the Ceratosauria and the Orionides, survived into the Cretaceous period. When the Cretaceous–Paleogene extinction event occurred, ceratosaurians and two groups of orionideans within the clade Coelurosauria, the Tyrannosauroidea and Maniraptoriformes, were still extant. Only one subgroup of maniraptoriformes, Aves, survived the extinction event and persisted to the present day.

Avetheropoda

Avetheropoda, or "bird theropods", is a clade that includes carnosaurians and coelurosaurs to the exclusion of other dinosaurs.

Cerapoda

Cerapoda ("ceratopsians and ornithopods") is a clade of the dinosaur order Ornithischia.

Dinosauriformes

Dinosauriformes is a clade of archosaurian reptiles that include the dinosaurs and their most immediate relatives. All dinosauriformes are distinguished by several features, such as shortened forelimbs and a partially to fully perforated acetabulum, the hole in the hip socket traditionally used to define dinosaurs. The oldest known member is Asilisaurus, dating to about 245 million years ago in the Anisian age of the middle Triassic period.

Haya griva

Haya is an extinct genus of basal neornithischian dinosaur known from Mongolia.

Jeholosauridae

Jeholosaurids were herbivorous neornithischian dinosaurs from the Cretaceous Period (Aptian - Santonian, with a possible Campanian record) of Asia. The family was first proposed by Han et al. in 2012. The jeholosaurids were defined as those ornithischians more closely related to Jeholosaurus shangyuanensis than to Hypsilophodon foxii, Iguanodon bernissartensis, Protoceratops andrewsi, Pachycephalosaurus wyomingensis, or Thescelosaurus neglectus. The Jeholosauridae includes the type genus Jeholosaurus and Yueosaurus.

Jingshanosaurus

Jingshanosaurus (meaning "Jingshan lizard") is a genus of sauropodomorph dinosaurs from the early Jurassic period.

Koreanosaurus

Koreanosaurus (meaning "Korean lizard") is a genus of ornithopod dinosaur. One species has been described, Koreanosaurus boseongensis.

Melanorosauridae

The Melanorosauridae were a family of sauropodomorph dinosaurs which lived during the Late Triassic and Early Jurassic. The name Melanorosauridae was first coined by Friedrich von Huene in 1929. Huene assigned several families of dinosaurs to the infraorder "Prosauropoda": the Anchisauridae, the Plateosauridae, the Thecodontosauridae, and the Melanorosauridae. Since then, these families have undergone numerous revisions. Galton and Upchurch (2004) considered Camelotia, Lessemsaurus, and Melanorosaurus members of the family Melanorosauridae. A more recent study by Yates (2007) indicates that the melanorosaurids were instead early sauropods.

Neornithischia

Neornithischia ("new ornithischians") is a clade of the dinosaur order Ornithischia. They are the sister group of the Thyreophora within the clade Genasauria. Neornithischians are united by having a thicker layer of asymmetrical enamel on the inside of their lower teeth. The teeth wore unevenly with chewing and developed sharp ridges that allowed neornithischians to break down tougher plant food than other dinosaurs. Neornithischians include a variety of basal forms historically known as "hypsilophodonts", including the Parksosauridae; in addition, there are derived forms classified in the groups Marginocephalia and Ornithopoda. The former includes clades Pachycephalosauria and Ceratopsia, while the latter typically includes Hypsilophodon and the more derived Iguanodontia.

Neotheropoda

Neotheropoda (meaning "new theropods") is a clade that includes coelophysoids and more advanced theropod dinosaurs, and the only group of theropods who survived the Triassic–Jurassic extinction event. Yet all of the neotheropods became extinct during the early Jurassic period except for Averostra.

Orionides

Orionides is a clade of tetanuran theropod dinosaurs from the Middle Jurassic to the Present. The clade includes most theropod dinosaurs, including birds.

Orodrominae

Orodrominae is a subfamily of parksosaurid dinosaurs from the Cretaceous of North America and Asia.

Oryctodromeus

Oryctodromeus (meaning "digging runner") was a genus of small parksosaurid dinosaur. Fossils are known from the middle Cretaceous Blackleaf Formation of southwestern Montana and the Wayan Formation of southeastern Idaho, USA, both of the Cenomanian stage, roughly 95 million years ago. A member of the small, presumably fast-running herbivorous family Parksosauridae, Oryctodromeus is the first dinosaur published that shows evidence of burrowing behavior.

Parksosauridae

Parksosauridae is a clade or family of small ornithischians which have previously been generally allied to hypsilophodontids. Parksosauridae is often considered a synonym of Thescelosauridae, but the two groups cannot be synonyms because Parksosauridae is defined as a stem, while Thescelosauridae is defined as a node.

Riojasauridae

Riojasauridae is a family of sauropod-like dinosaurs from the Upper Triassic. It is known primarily from the genera Riojasaurus and Eucnemesaurus. Sites containing Riojasauridae include the Lower Elliot Formation of Orange Free State, South Africa (where fossils of Eucnemesaurus have been found), and Ischigualasto, in La Rioja Province, Argentina ( where fossils of Riojasaurus have been recovered).

Thescelosaurinae

Thescelosaurinae is a subfamily of ornithischian dinosaurs from the Early Cretaceous of Asia and the Late Cretaceous of North America.

Xixiposaurus

Xixiposaurus is a genus of prosauropod dinosaur which existed in what is now Lower Lufeng Formation, China during the lower Jurassic period. It was first named by Sekiya Toru in 2010 and the type species is Xixiposaurus suni.

Languages

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.