''Chondrosteosaurus'' (meaning "cartilage and bone lizard") was a sauropod

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

from Early Cretaceous

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

. The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

, ''Chondrosteosaurus gigas'', was described and named by Richard Owen in 1876. The fossils of ''Chondrosteosaurus'' were discovered in the

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 Vect ...

on the

Isle of Wight The Isle of Wight ( ) is a Counties of England, county in the English Channel, off the coast of Hampshire, from which it is separated by the Solent. It is the List of islands of England#Largest islands, largest and List of islands of England#Mo ...

, likely Brighstone or

Brook A brook is a small river or natural stream of fresh water. It may also refer to: Computing *Brook, a programming language for GPU programming based on C *Brook+, an explicit data-parallel C compiler *BrookGPU, a framework for GPGPU programming ...

. ''C. gigas'' is known only from two neck vertebrae (specimens BMNH 46869, the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of sever ...

, and BMNH 46870), with distinctive hollows and internal passages now interpreted as evidence of pneumatic air sacs. Paleontologist

Harry Seeley Harry Govier Seeley (18 February 1839 – 8 January 1909) was a British paleontologist. Early life Seeley was born in London on 18 February 1839, the second son of Richard Hovill Seeley, a goldsmith, and his second wife Mary Govier. When his fat ...

had interpreted similar structures as pneumatic in his specimen of ''

Ornithopsis ''Ornithopsis'' (meaning "bird-likeness") was a medium-sized Early Cretaceous sauropod dinosaur, from England. The type species, which is the only species seen as valid today, is ''O. hulkei''. History of discovery Gideon Algernon Mantell descr ...

''.Seeley, H.G. (1870). "On ''Ornithopsis'', a gigantic animal of the pterodactyle kind from the Wealden." ''Annals and Magazine of Natural History'', Series 4, 5: 279-283. Owen disagreed with Seeley's concept of a giant creature bridging the gap between

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...

s or

pterosaur Pterosaurs (; from Greek ''pteron'' and ''sauros'', meaning "wing lizard") is an extinct clade of flying reptiles in the order, Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cretaceous (228 ...

s (Owen considered sauropods to be whale-like marine reptiles), and while he acknowledged that the external cavities on the vertebrae may have been connected to the lungs, he interpreted the internal passages as having been filled with cartilage (hence his name for the genus, ''Chondrosteosaurus'' or "cartilage and bone lizard").Owen, R. (1876). "Monograph on the fossil Reptilia of the Wealden and Purbeck Formations. Supplement 7. Crocodilia (''Poikilopleuron'') and Dinosauria? (''Chondrosteosaurus'')." ''Palaeontographical Society Monographs'', 30: 1-7. Owen also named a second species, '' Chondrosteosaurus magnus'', that today no longer is considered to belong to ''Chondrosteosaurus'' but instead ''

''.

References

External links

Discussion of ''Chondrosteosaurus'' with image

Eusauropoda Barremian life Early Cretaceous dinosaurs of Europe Cretaceous England Fossils of England Fossil taxa described in 1876 Taxa named by Richard Owen {{Sauropodomorph-stub