iPedia Free Information Center

Information about Gastralium

Gastralia (singular gastralium) are dermal bones today found in the ventral body wall of crocodilians and Sphenodon. They are found between the sternum and pelvis, and do not articulate with the vertebrae. In modern animals, they provide support for the abdomen and attachment sites for abdominal muscles. These bones may have been derived from the ventral scales found in animals like rhipidistians, labyrinthodonts, and Acanthostega, and may be related to ventral elements of turtle plastrons.[1] Similar but not homologous cartilagenous elements are found in the ventral body walls of lizards and anurans. The terminology for these groups of structures is confused; both types, along with sternal ribs (ossified costal cartilages), have been called abdominal ribs, a term which should be avoided.[2]

Gastralia are also present in a variety of extinct animals, including theropod and prosauropod dinosaurs, pterosaurs, plesiosaurs, and champsosaurs. In dinosaurs, the elements articulate with each other in a sort of zig-zag along the midline and may have aided in respiration.[2] Although they were thought to be present in some basal ornithischian dinosaurs,[3] and sauropods (most notably Eobrontosaurus), the possible occurrences have been shown to be mistaken.[2]

References

1. ^ Kardong, Kenneth V. (2002). Vertebrates: Comparative Anatomy, Function, Evolution, 3rd, New York: McGraw-Hill, 291-293. ISBN 0-07-290956-0. 
2. ^ Claessens, Leon P.A.M. (March 2004). "Dinosaur gastralia: origin, morphology, and function". Journal of Vertebrate Paleontology 24 (1): 89-106. DOI:10.1671/A1116-8. 
3. ^ Claessens, Leon (1995-11-28). Dinosaur gastralia and their function in respiration. Dinosaur Mailing List. Retrieved on 2007-07-08.

External links

The dermal bone, the pattern and form of bones derived from intramembranous ossification, define essential components of the vertebrate skeleton including the skull, jaws, gills, fins and exoskeleton.
..... Click the link for more information.
In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. Non-scientists often wonder why zoological and human anatomists use complex terminology to describe locations on a body, when common terms like "up",
..... Click the link for more information.
Crocodilia
Owen, 1842

black: range of Crocodilia


Families
  • Gavialidae
  • Alligatoridae
  • Crocodylidae


Crocodilia
..... Click the link for more information.
Sphenodon
Gray, 1831

black: range (North Island, New Zealand)


Species

Sphenodon punctatus (Gray, 1842)
Sphenodon guntheri (Buller, 1877)
Sphenodon diversum
..... Click the link for more information.
sternum (from Greek στέρνον, sternon, "chest" and hebrew pronounced "Shamokin" also meaning chest) or breastbone is a long, flat bone located in the center of the thorax (chest).
..... Click the link for more information.
pelvis (pl. pelvises or pelves) is the bony structure located at the base of the spine (properly known as the caudal end). The pelvis incorporates the socket portion of the hip joint for each leg (in bipeds) or hind leg (in quadrupeds).
..... Click the link for more information.
The Vertebral Column (singular: vertebra) are the individual irregular bones that make up the spinal column (aka ischis) — a flexuous and flexible column.
..... Click the link for more information.
To comply with Wikipedia's this section of the article needs a complete rewrite.
Please discuss this issue on the talk page and read the layout guide to make sure the section will be inclusive of all essential details. This article has been tagged since September 2007.
..... Click the link for more information.
Rhipidistia

Orders

See text.

The Rhipidistia were lobe-finned fishes that are the ancestors of the tetrapods. Taxonmists traditionally considered the Rhipidistia a subgroup of Crossopterygii that described a group of fish that lived during the
..... Click the link for more information.
Labyrinthodont (Greek, "maze-toothed") is an obsolete term for any member of an extinct superorder or subclass (Labyrinthodontia) of amphibians, which constituted some of the dominant animals of Late Paleozoic and Early Mesozoic times (about 350 to 210 million years ago).
..... Click the link for more information.
Acanthostegidae

Genus: Acanthostega

Species: A. gunnari

Binomial name
Acanthostega gunnari
Jarvik, 1952
..... Click the link for more information.
Testudines
Linnaeus, 1758

Diversity
ca. 300 species in 14 extant families.

blue: sea turtles, black: land turtles


Suborders

Cryptodira
Pleurodira
See text for families.
..... Click the link for more information.
plastron is the nearly flat part of the shell structure of a turtle or tortoise, what one would call the belly, similar in composition to the carapace; with an external layer of horny material divided into plates called scutes and an underlying layer of interlocking bones.
..... Click the link for more information.
In evolutionary biology, homology is any similarity between characters that is due to their shared ancestry. There are examples in different branches of biology. Anatomical structures that perform the same function in different biological species and evolved from the same structure
..... Click the link for more information.
Cartilage is a type of dense connective tissue. It is composed of collagen fibers and/or elastin fibers, and can supply smooth surfaces for the movement of articulating bones.
..... Click the link for more information.
Lacertilia*
Günther, 1867

Families

Many, see text.

Lizards are reptiles of the order Squamata, normally possessing four legs, external ear openings and movable eyelids.
..... Click the link for more information.
FROG

General
Dianelos Georgoudis, Damian Leroux, and Billy Simón Chaves
1998

Cipher detail
Key size(s):| 128, 192, or 256 bits

Block size(s):| 128 bits

8
..... Click the link for more information.
Ossification is the process of bone formation, in which connective tissues, such as cartilage are turned to bone or bone-like tissue. The ossified tissue is invaginated with blood vessels. These blood vessels bring minerals like calcium and deposit it in the ossifying tissue.
..... Click the link for more information.
The costal cartilages are bars of hyaline cartilage which serve to prolong the ribs forward and contribute very materially to the elasticity of the walls of the thorax.

Differences from 1-12


..... Click the link for more information.
extinction is the cessation of existence of a species or group of taxa, reducing biodiversity. The moment of extinction is generally considered to be the death of the last individual of that species (although the capacity to breed and recover may have been lost before this point).
..... Click the link for more information.
Theropoda
Marsh, 1881

Infraorders
  • Carnosauria
  • Ceratosauria
  • Deinonychosauria
  • Ornithomimosauria
  • Oviraptorosauria


Theropods ('beast feet') are a group of bipedal saurischian dinosaurs.
..... Click the link for more information.
Prosauropoda
von Huene, 1920

Families

See text
Prosauropoda or prosauropods were a group of early herbivorous dinosaurs that lived during the Triassic and early Jurassic periods.
..... Click the link for more information.
Dinosauria *
Owen, 1842

Orders & Suborders
  • Ornithischia
  • Cerapoda
  • Thyreophora
  • Saurischia

..... Click the link for more information.
Pterosauria
Kaup, 1834

Suborders

Pterodactyloidea
Rhamphorhynchoidea *

Pterosaurs (/ˈtɛ.
..... Click the link for more information.
Plesiosauroidea
Gray, 1825

Families

Cimoliasauridae
Cryptoclididae
Elasmosauridae
Plesiosauridae
Polycotylidae

Plesiosaurs (IPA /ˈplisɪəˌsɔɹ/
..... Click the link for more information.
Choristodera
Cope, 1884

Groups

Monjurosuchidae
Hyphalosauridae
Cteniogenidae
Simoedosauridae
Champsosauridae
Choristodera is an order of semi-aquatic diapsid reptiles which ranged from the Middle Jurassic, or possibly Late Triassic, to
..... Click the link for more information.
In animal physiology, respiration is the transport of oxygen from the ambient air to the tissue cells and the transport of carbon dioxide in the opposite direction. This is in contrast to the biochemical definition of respiration, which refers to cellular respiration
..... Click the link for more information.
In phylogenetics, basal members of a group diverged earlier than a subgroup of others (or vice versa). It is often used in opposition to the word derived. The following are example usages of the term basal:....
..... Click the link for more information.
Ornithischia
Seeley, 1888

Suborders
  • Cerapoda
  • Thyreophora


Ornithischia or Predentata is an order of beaked, herbivorous dinosaurs.
..... Click the link for more information.
Sauropoda
Marsh, 1878

Families

See text

Sauropoda, the sauropods, are a suborder or infraorder of the saurischian ("lizard-hipped") dinosaurs. They were the largest animals ever to have lived on land.
..... Click the link for more information.


This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.
Herod_Archelaus


page counter