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Dissorophidae is an extinct family of medium-sized, temnospondyl amphibians that flourished during the Late Pennsylvanian and early Permian periods in what is now North America and Europe. Despite being amphibians, they seem to be well developed for life on land, with well-developed limbs, solid vertebrae, and a row of armour plates of dermal bone, which both protected the animal and further strengthened the backbone. A well known genus is ''Cacops'', a squat solid animal from the late Early Permian (Artinskian age) Clear Fork group of Texas, with a relatively huge head, and a row of armor plates along the back. In the similar but slightly larger and more specialised genus, ''Platyhystrix'', whose fossil remains are known from the Cutler Group of Utah, Coloardo, and New Mexico, the armor developed into a sort of ridge or sail. Not all Dissorophids were squat-bodied big headed animals. ''Fayella'', from the late Artinskian of Oklahoma, was lightly built with long limbs, obviously relying on speed rather than armour plating as a defense against predators. There are a number of related forms which seem to have been more aquatic, which are known from the Late Permian of Russia and the Early Triassic of Gondwana. It has been suggested that the Dissorophidae may be close to the ancestry of modern amphibians (Lissamphibia), as it is closely related to another family called Amphibamidae that is often considered ancestral to this group,〔Ruta M, Coates MI. 2007. Dates, nodes and character conflict: addressing the lissamphibian origin problem. ''Journal of Systematic Palaeontology'' 5: 69-122. doi:10.1017/S1477201906002008〕 although it could also be on the tetrapod stem. ==Fossil range== Below is a timeline of the known fossil ranges of dissorophids. ImageSize = width:700px height:auto barincrement:15px PlotArea = left:10px bottom:50px top:10px right:10px Period = from:-310 till:-251 TimeAxis = orientation:horizontal ScaleMajor = unit:year increment:10 start:-310 ScaleMinor = unit:year increment:5 start:-310 TimeAxis = orientation:hor AlignBars = justify Colors = #legends id:CAR 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Dissorophidae」の詳細全文を読む スポンサード リンク
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