Umoonasaurus demoscyllus
An archaic crested plesiosaur from the Lower Cretaceous of Australia
Kear, B.P., Schroeder, N.I. & Lee, M.S.Y. (2006) An archaic crested plesiosaur in opal from the Lower Cretaceous high-latitude deposits of Australia. Proceedings of the Royal Society B: Biology Letters. FirstCite Early Online Publishing.
Abstract:
"_Umoonasaurus demoscyllus_ gen. et sp. nov. is a new small-bodied (approx. 2.5m) pliosauroid plesiosaur from the Lower Cretaceous (Aptian-Albian) of southern Australia. It is represented by several partial skeletons (one with a near complete skull is the most complete opalized vertebrate fossil yet known), and is unique in having large crests on the skull midline and above the orbits.
_Umoonasaurus_ is surprisingly archaic despite its relatively late age (approx. 115Myr ago) - being simultaneously the most basal (primitive) and last surviving rhomaleosaurid. Notably, it lacks the ‘pliosauromorph' features (large head, short neck, gigantism) typically characterizing many more derived Jurassic rhomaleosaurids; thus, reinforcing the suspected convergent evolution of the ‘pliosauromorph' hypercarnivore body plan. _Umoonasaurus_ inhabited an Early Cretaceous high-latitude (approx. 70°S) inland seaway subject to seasonally near-freezing climatic conditions. This extreme environment supported a diverse range of plesiosaur taxa, suggesting that these marine reptiles might have possessed adaptations (e.g. heightened metabolic levels) to cope with cold-water temperatures.
Indeed, survival of ancient endemic lineages such as _Umoonasaurus_ is a common phenomenon in Australian Cretaceous vertebrate assemblages and might have been facilitated by isolation in low-temperature high-latitude regions."
Souce : Dinodata
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Posté par Damien35
Posté par Damien35
Une petite image de la bebete :
Source : http://www.deviantart.com/
Source : http://www.deviantart.com/
Posté par Pyroraptor
Hargh je vois pas l'image 
Posté par Damien35
Essaie ça :
<A HREF="http://ic3.deviantart.com/fs8/i/2005/359/7/7/Umoonasaurus_Demoscyllus_by_evil_santa.jpg">http://ic3.deviantart.com/fs8/i/2005/359/7/7/Umoonasaurus_Demoscyllus_by_evil_santa.jpg</A>
<A HREF="http://ic3.deviantart.com/fs8/i/2005/359/7/7/Umoonasaurus_Demoscyllus_by_evil_santa.jpg">http://ic3.deviantart.com/fs8/i/2005/359/7/7/Umoonasaurus_Demoscyllus_by_evil_santa.jpg</A>
Posté par Pyroraptor
Marche pas non plus 
Posté par Carcharo
Http://gigadino.perso.orange.fr/news.html
Posté par Carcharo
Http://www.journals.royalsoc.ac.uk/media/public/contributionsupplementalmaterials/8/3/n/1/83n10t6p17011132/archive1.pdf
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