Calamosaurus

Calamosaurus (meaning "reed lizard") was a genus of small theropod dinosaur from the Barremian-age Lower Cretaceous Wessex Formation of the Isle of Wight, England. It is based on two cervical vertebrae (BMNH R901), collected by Reverend William Fox.

Calamosaurus
Temporal range: Early Cretaceous, Barremian
Calamosaurus
Cervical vertebra of Calamosaurus foxi
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Order: Saurischia
Suborder: Theropoda
Family: Compsognathidae
Genus: Calamosaurus
Lydekker, 1891
Species:
C. foxi
Binomial name
Calamosaurus foxi
(Lydekker, 1889 [originally Calamospondylus])

History and taxonomy

Richard Lydekker ran across these bones when cataloguing the Fox collection and named them Calamospondylus, noting their similarity to those of Coelurus.[1] Unfortunately, Calamospondylus had already been coined in 1866 (ironically by Reverend Fox himself, the very man honored in Lydekker's species name).[2] Lydekker renamed it in 1891 to its present title.[3] He also at this time provisionally referred to it a tibia, BMNH R186, which may be from a basal coelurosaurian like a compsognathid.[4]

Because of its sparse remains, it has received little attention. Often, it has been synonymized with Calamospondylus as part of a long, confusing taxonomic tangle,[5][6][7] although there is no comparable material between the two genera.[4] Modern reviews have regarded it as a dubious theropod,[8][9] although potentially a valid coelurosaurian.[4]

In 2002 Paul Turner found a dorsal vertebra near Grange Chine on the Isle of Wight. An associated partial tibia and metatarsal fragment were subsequently discovered by Oliver Mattsson and referred to Calamosaurus.[10] Another specimen referred to Calamosaurus was collected by local fossil hunter Kai Bailey in 2014. Both specimens are on display at the Dinosaur Expeditions, Conservation and Palaeoart Centre near Brighstone, Isle of Wight.

A neck vertebra of a Calamosaurus was found near Chilton Chine on the Isle of Wight by local fossil hunter Dave Badman. The newly discovered vertebra has gone on display at the Dinosaur Isle Museum in Sandown, Isle of Wight.

Paleobiology

As a possible basal coelurosaur, Calamosaurus would have been a small, agile, bipedal carnivore. Naish et al. (2001) estimate the living animal would have been around 3–5 meters (9.8–16.4 ft) long, with a small head given the build of the neck vertebrae.[4]

References

  1. ^ Lydekker. R. (1889). On a coelurid dinosaur from the Wealden. Geological Magazine 6:119-121.
  2. ^ Fox, W.D. in Anonymous. (1866) Another Wealden reptile. Athenaeum 2014:740.
  3. ^ Lydekker. R. (1891). On certain ornithosaurian and dinosaurian remains. Quarterly Journal of the Geological Society of London 47:41-44.
  4. ^ a b c d Naish, D., Hutt, S., and Martill, D.M. (2001). Saurischian dinosaurs 2: theropods. In: Martill, D.M., and Naish, D. (eds.). Dinosaurs of the Isle of Wight. The Palaeontological Association:London, 242-309. ISBN 0-901702-72-2
  5. ^ Swinton, W.E. (1936). The dinosaurs of the Isle of Wight. Proceedings of the Geologists' Association 47(3):204-220.
  6. ^ Romer, A.S. (1956). Osteology of the Reptiles. University of Chicago Press:Chicago, 1-772. ISBN 0-89464-985-X
  7. ^ Steel, R. (1970). Part 14. Saurischia. Handbuch der Paläoherpetologie/Encyclopedia of Paleoherpetology. Part 14. Gustav Fischer Verlag:Stuttgart, 1-87.
  8. ^ Norman, D.B. (1990). Problematic theropoda: "coelurosaurs". In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). The Dinosauria. University of California Press:Berkeley, 280-305. ISBN 0-520-06727-4.
  9. ^ Holtz Jr., T.R., Molnar, R.E., and Currie, P.J. (2004). Basal Tetanurae. In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). The Dinosauria (second edition). University of California Press:Berkeley, 71-110. ISBN 0-520-24209-2.
  10. ^ Naish, D. 2011. Theropod dinosaurs. In Batten, D. J. (ed.) English Wealden Fossils. The Palaeontological Association (London), pp. 526–559.
1889 in paleontology

Paleontology or palaeontology (from Greek: paleo, "ancient"; ontos, "being"; and logos, "knowledge") is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 1889.

1891 in paleontology

Paleontology or palaeontology (from Greek: paleo, "ancient"; ontos, "being"; and logos, "knowledge") is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 1891.

Barremian

The Barremian is an age in the geologic timescale (or a chronostratigraphic stage) between 129.4 ± 1.5 Ma (million years ago) and 125.0 ± 1.0 Ma). It is a subdivision of the Early Cretaceous epoch (or Lower Cretaceous series). It is preceded by the Hauterivian and followed by the Aptian stage.

Calamospondylus

Calamospondylus (meaning "quill vertebrae") was a theropod dinosaur genus. It lived during the Early Cretaceous, and its fossils were found in England. The type species, Calamospondylus oweni, was described anonymously by amateur paleontologist William D. Fox in 1866, but is based on fragmentary material. It has been part of a confusing taxonomic issue also involving Aristosuchus and Calamosaurus (which was also named "Calamospondylus", but then renamed). It may have been a primitive oviraptorosaurian.

Compsognathidae

Compsognathidae is a family of coelurosaurian theropod dinosaurs. They were small carnivores, generally conservative in form, hailing from the Jurassic and Cretaceous Periods. The bird-like features of these species, along with other dinosaurs such as Archaeopteryx inspired the idea for the connection between dinosaur reptiles and modern-day avian species. Compsognathid fossils preserve diverse integument — skin impressions are known from four genera commonly placed in the group, Compsognathus, Sinosauropteryx, Sinocalliopteryx, and Juravenator. While the latter three show evidence of a covering of some of the earliest primitive feathers over much of the body, Juravenator and Compsognathus also show evidence of scales on the tail or hind legs.

The first member of the group, Compsognathus, was discovered in 1861, after Johann A. Wagner published his description of the taxon. The family it was created by Edward Drinker Cope in 1875. This classification was accepted by Othniel Charles Marsh in 1882, and added to the Coelurosauria clade by Friedrich von Huene in 1914 after additional fossils had been found. With further discoveries, fossils have been uncovered across three different continents, in the countries of China, France, Germany, Italy, and Brazil. Assignment to Compsognathidae is usually determined through examination of the metacarpal, which is used to separate Compsognathidae from other dinosaurs. However, classification is still complicated due to similarities to the body of several other theropod dinosaurs, as well as the lack of unifying, diagnostic features that are shared by all compsognathids.

List of European dinosaurs

Dinosaurs evolved partway through the Triassic period of the Mesozoic era, around 230 Ma (million years ago). At that time, the earth had one supercontinental landmass, called Pangaea, of which Europe was a part. So it remained throughout the Triassic. By the start of the Jurassic period, some 30 million years later, the supercontinent began to split into Laurasia and Gondwana. The largest inlet from Panthalassa, the superocean that surrounded Pangaea, was called the Tethys Ocean, and as this inlet cut deeper into the supercontinent, much of Europe was flooded.

By the Cretaceous, from 145 to 66 million years ago, the continents were beginning to approach their present shapes, but not their present positions, and Europe remained tropical. At times, it was a chain of island-microcontinents including Baltica and Iberia.

Europe is relatively rich in fossils from the Jurassic-Cretaceous boundary, and much of what is known about European dinosaurs dates from this time. As the timeline below illustrates, there are substantial gaps in our knowledge from the rest of the Mesozoic. The absence of dinosaur genera from this time is because few fossils have been discovered, and almost certainly not because Europe contained few types of dinosaur—except, perhaps, immediately after the Triassic–Jurassic extinction event.

List of dinosaur genera

This list of dinosaurs is a comprehensive listing of all genera that have ever been included in the superorder Dinosauria, excluding class Aves (birds, both living and those known only from fossils) and purely vernacular terms.

The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful (nomen dubium), or were not formally published (nomen nudum), as well as junior synonyms of more established names, and genera that are no longer considered dinosaurs. Many listed names have been reclassified as everything from birds to crocodilians to petrified wood. The list contains 1559 names, of which approximately 1192 are considered either valid dinosaur genera or nomina dubia.

Sarcolestes

Sarcolestes (meaning "flesh robber") is an extinct genus of ankylosaurian ornithischian dinosaur from the Oxford Clay of England. The current type and only species is S. leedsi, and the holotype is a single partial left mandible. The genus and species were named in 1893 by Richard Lydekker, who thought they belonged to a theropod.

Wessex Formation

The Wessex Formation is a fossil-rich English geological formation that dates from the Berriasian to Barremian stages (about 145–125 million years ago) of the Early Cretaceous. It forms part of the Wealden Group and underlies the younger Vectis Formation and overlies the Durlston Formation. The dominant lithology of this unit is mudstone with some interbedded sandstones.

William Fox (palaeontologist)

William D. Fox (9 August 1813 – 1881) was an English clergyman and palaeontologist who worked on the Isle of Wight and made some significant discoveries of dinosaur fossils.

The Reverend William D. Fox was born in Cumberland. He moved to the Isle of Wight in 1862 to take up the post of curate at the Parish church of St Mary the Virgin in Brixton (now known as Brighstone). He resigned his post in 1867 but continued to live in the area to carry on his collecting. In 1875, he became curate of nearby Kingston, near Shorwell.Although lacking formal scientific training Fox was remarkably astute and discussed his findings with eminent palaeontologists of the day including John Hulke (1830-1895) and Sir Richard Owen. Fox had easy access to Brighstone Bay from his home, Myrtle Cottage in Brighstone, and so spent many an hour collecting fossils, much to the detriment of his pastoral work; in fact, it was said of him at the time, by the wife of the vicar, that it was "always bones first and the parish next". He is also quoted as having written in a letter to Owen "I cannot leave this place while I have any money left to live on, I take such deep [sic] in hunting for old dragons".In 1882 Fox's collection of more than 500 specimens was acquired by the Natural History Museum after his death.Fox is credited with the finding of several species, most described by his friend Owen, and named by him after their finder. These include Polacanthus foxii, Hypsilophodon foxii, Eucamerotus foxi, Iguanodon foxii, Calamosaurus foxii (formerly Calamospondylus) and Aristosuchus.

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.