Cardiodon
Encyclopedia
Cardiodon was a genus
of sauropod dinosaur
, based on a tooth
from the late Bathonian
-age Middle Jurassic
Forest Marble Formation of Wiltshire
, England
. Historically, it is very obscure and usually referred to Cetiosaurus
, but recent analyses suggest that it is a distinct genus, and possibly related to Turiasaurus
.
named the genus for a now-lost tooth found near Bradford-on-Avon, but did not assign it a species name at the time; a few years later, he added the species name. Within a few decades, he and others were viewing it as a possible synonym of his most well-known sauropod genus, Cetiosaurus
. Richard Lydekker
formalized this view in a roundabout way in 1890, by assigning Cetiosaurus oxoniensis to Cardiodon on the basis of teeth from Oxfordshire
associated with a skeleton of C. oxoniensis. He also added a second tooth (BMNH R1527) from the Great Oolite
near Cirencester
, Gloucestershire
. More typically, Cardiodon has been assigned to Cetiosaurus, sometimes as a separate species.
In 2003, Paul Upchurch and John Martin, reviewing Cetiosaurus, found that there is little evidence to assign the C. oxoniensis teeth to the skeleton, and the "C. oxoniensis" teeth differ from the Cardiodon teeth (Cardiodon teeth are convex facing the tongue
); therefore, they supported Cardiodon being retained as its own genus. Upchurch et al. (2004) repeated this assessment, and found that though the teeth have no known autapomorphies, they are those of an eusauropod. More recently, Royo-Torres et al. (2006), in their description of Turiasaurus
, pointed out Cardiodon as a possible relative to their new, giant sauropod.
al herbivore
, but because of the scanty remains, much more cannot be said.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of sauropod dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
, based on a tooth
Tooth
Teeth are small, calcified, whitish structures found in the jaws of many vertebrates that are used to break down food. Some animals, particularly carnivores, also use teeth for hunting or for defensive purposes. The roots of teeth are embedded in the Mandible bone or the Maxillary bone and are...
from the late Bathonian
Bathonian
In the geologic timescale the Bathonian is an age or stage of the Middle Jurassic. It lasted from approximately 167.7 Ma to around 164.7 Ma...
-age Middle Jurassic
Middle Jurassic
The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from 176-161 million years ago. In European lithostratigraphy, rocks of this Middle Jurassic age are called the Dogger....
Forest Marble Formation of Wiltshire
Wiltshire
Wiltshire is a ceremonial county in South West England. It is landlocked and borders the counties of Dorset, Somerset, Hampshire, Gloucestershire, Oxfordshire and Berkshire. It contains the unitary authority of Swindon and covers...
, England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
. Historically, it is very obscure and usually referred to Cetiosaurus
Cetiosaurus
Cetiosaurus meaning 'whale lizard', from the Greek cetus/κητος meaning 'sea monster' and saurus/σαυρος meaning 'lizard', was a sauropod dinosaur from the Mid to Late Jurassic Period in what are now Europe and Africa. It is estimated to have been about long and to have weighed roughly...
, but recent analyses suggest that it is a distinct genus, and possibly related to Turiasaurus
Turiasaurus
Turiasaurus is a genus of sauropod dinosaur from the Jurassic-Cretaceous boundary...
.
History and Taxonomy
Richard OwenRichard Owen
Sir Richard Owen, FRS KCB was an English biologist, comparative anatomist and palaeontologist.Owen is probably best remembered today for coining the word Dinosauria and for his outspoken opposition to Charles Darwin's theory of evolution by natural selection...
named the genus for a now-lost tooth found near Bradford-on-Avon, but did not assign it a species name at the time; a few years later, he added the species name. Within a few decades, he and others were viewing it as a possible synonym of his most well-known sauropod genus, Cetiosaurus
Cetiosaurus
Cetiosaurus meaning 'whale lizard', from the Greek cetus/κητος meaning 'sea monster' and saurus/σαυρος meaning 'lizard', was a sauropod dinosaur from the Mid to Late Jurassic Period in what are now Europe and Africa. It is estimated to have been about long and to have weighed roughly...
. Richard Lydekker
Richard Lydekker
Richard Lydekker was an English naturalist, geologist and writer of numerous books on natural history.-Biography:...
formalized this view in a roundabout way in 1890, by assigning Cetiosaurus oxoniensis to Cardiodon on the basis of teeth from Oxfordshire
Oxfordshire
Oxfordshire is a county in the South East region of England, bordering on Warwickshire and Northamptonshire , Buckinghamshire , Berkshire , Wiltshire and Gloucestershire ....
associated with a skeleton of C. oxoniensis. He also added a second tooth (BMNH R1527) from the Great Oolite
Great Oolite
The Great Oolite is a geological formation in Europe. It dates back to the Middle Jurassic.-Vertebrate fauna:This Limestone is dominant in many areas of the UK particularly in Birmingham and Anglesy. It is composed of oolites and lithic fragments...
near Cirencester
Cirencester
Cirencester is a market town in east Gloucestershire, England, 93 miles west northwest of London. Cirencester lies on the River Churn, a tributary of the River Thames, and is the largest town in the Cotswold District. It is the home of the Royal Agricultural College, the oldest agricultural...
, Gloucestershire
Gloucestershire
Gloucestershire is a county in South West England. The county comprises part of the Cotswold Hills, part of the flat fertile valley of the River Severn, and the entire Forest of Dean....
. More typically, Cardiodon has been assigned to Cetiosaurus, sometimes as a separate species.
In 2003, Paul Upchurch and John Martin, reviewing Cetiosaurus, found that there is little evidence to assign the C. oxoniensis teeth to the skeleton, and the "C. oxoniensis" teeth differ from the Cardiodon teeth (Cardiodon teeth are convex facing the tongue
Tongue
The tongue is a muscular hydrostat on the floors of the mouths of most vertebrates which manipulates food for mastication. It is the primary organ of taste , as much of the upper surface of the tongue is covered in papillae and taste buds. It is sensitive and kept moist by saliva, and is richly...
); therefore, they supported Cardiodon being retained as its own genus. Upchurch et al. (2004) repeated this assessment, and found that though the teeth have no known autapomorphies, they are those of an eusauropod. More recently, Royo-Torres et al. (2006), in their description of Turiasaurus
Turiasaurus
Turiasaurus is a genus of sauropod dinosaur from the Jurassic-Cretaceous boundary...
, pointed out Cardiodon as a possible relative to their new, giant sauropod.
Paleobiology
As a sauropod, Cardiodon would have been a large, quadrupedQuadruped
Quadrupedalism is a form of land animal locomotion using four limbs or legs. An animal or machine that usually moves in a quadrupedal manner is known as a quadruped, meaning "four feet"...
al herbivore
Herbivore
Herbivores are organisms that are anatomically and physiologically adapted to eat plant-based foods. Herbivory is a form of consumption in which an organism principally eats autotrophs such as plants, algae and photosynthesizing bacteria. More generally, organisms that feed on autotrophs in...
, but because of the scanty remains, much more cannot be said.