On the Affinities of Tetraceratops insignis, an Early Permian Synapsid

  title={On the Affinities of Tetraceratops insignis, an Early Permian Synapsid},
  author={Eli Amson and Michel Laurin},
The affinities of the Early Permian synapsid Tetraceratops insignis have been reevaluated several times since the early 20th century, being considered as an eothyridid, a sphenacodontid, or a therapsid. This controversy continues into the 21st century, with recently raised doubts about the interpretation of Tetraceratops as the oldest known therapsid, a hypothesis supported by the only redescription of this fossil in the second half of the 20th century. Our study examines the arguments proposed… 
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ABSTRACT Preparation and restudy of the Lower Permian synapsid Tetraceratops insignis demonstrate that it is related more closely to therapsids than to other Permo-Carboniferous synapsids. As the
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