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| image = Hesperosuchus_BW.jpg | image_width = 250px | image_caption = ''Hesperosuchus'' an early crocodylomorph | authority = Hay, 1930 | subdivision_ranks = Clades | subdivision = See text. }} Crocodylomorpha is a group of archosaurs that includes the crocodilians and their extinct relatives. During Mesozoic and early Cenozoic times, Crocodylomorpha was far more diverse than it is now. Triassic forms were small, lightly built, active terrestrial animals. These were supplanted during the early Jurassic by various aquatic and marine forms. The Later Jurassic, Cretaceous, and Cenozoic saw a wide diversity of terrestrial and semi-aquatic lineages. "Modern" crocodilians do not appear until the Late Cretaceous. Among the largest crocodylomorphs are the 7 metre long ''Crocodylus anthropophagus'', the 11 metre long ''Sarcosuchus imperator'', the 12 metre long ''Deinosuchus hatcheri'' and the 9 metre long ''Machimosaurus hugii''. ==Evolutionary history== When their extinct species and stem group are examined, the crocodylian lineage (clade Crurotarsi) proves to have been a very diverse and adaptive group of reptiles. Not only are they an ancient group of animals, at least as old as the dinosaurs, they also evolved into a great variety of forms. The earliest forms, the sphenosuchians, evolved during the Late Triassic, and were highly gracile terrestrial forms built like greyhounds. During the Jurassic and the Cretaceous, marine forms in the family Metriorhynchidae, such as ''Metriorhynchus'', evolved forelimbs that were paddle-like and had a tail similar to modern fish. ''Dakosaurus andiniensis'', a species closely related to ''Metriorhynchus'', had a skull that was adapted to eat large marine reptiles. Several terrestrial species during the Cretaceous evolved herbivory, such as ''Simosuchus clarki'' and ''Chimaerasuchus paradoxus''. A number of lineages during the Cenozoic became wholly terrestrial predators. 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「Crocodylomorpha」の詳細全文を読む スポンサード リンク
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