American Jurassic Symmetrodonts and Rhaetic "Pantotheres"

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Science  24 Feb 1967:
Vol. 155, Issue 3765, pp. 1006-1009
DOI: 10.1126/science.155.3765.1006


The molar morphology of the symmetrodonts Tinodon and Eurylambda from the late Jurassic of North America is virtually identical to that of so-called "pantotheres" from the Rhaetic of Wales. Therefore a primitive symmetrodont molar pattern was probably present in the phylogeny of pantotherian and tribosphenic molars. Occlusion of Tinodon and Eurylambda produced complex wear facets unlike the simple trigon-trigonid shear surfaces of Spalacotherium and Peralestes.