Tetraceratops

Tetraceratops
Temporal range: Early Permian, 275 Ma
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Holotype
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Clade: Pantherapsida
Genus: †Tetraceratops
Matthew, 1908
Type species
†Tetraceratops insignis
Matthew, 1908

Tetraceratops insignis ("four-horned face emblem") is an extinct synapsid from the Early Permian that was formerly considered the earliest known representative of Therapsida, a group that includes mammals and their close extinct relatives.[1][2][3] It is known from a single 90-millimetre-long (3.5 in) skull, discovered in Texas in 1908. According to a 2020 study, it should be classified as a primitive non-therapsid sphenacodont rather than a genuine basal therapsid.[4]

  1. ^ Laurin, M.; Reisz. R. R. (1996). "The osteology and relationships of Tetraceratops insignis, the oldest known therapsid". Journal of Vertebrate Paleontology. 16 (1): 95–102. doi:10.1080/02724634.1996.10011287.
  2. ^ D. W. Dilkes, R. R. Reisz (1996). "First Record of a Basal Synapsid ('Mammal-Like Reptile') in Gondwana". Proceedings of the Royal Society B. 263 (1374): 1168. doi:10.1098/rspb.1996.0170.
  3. ^ Amson, E.; Laurin M. (2011). "On the affinities of Tetraceratops insignis, an Early Permian synapsid". Acta Palaeontologica Polonica. 56 (2): 301–312. doi:10.4202/app.2010.0063.
  4. ^ Cite error: The named reference Spindler was invoked but never defined (see the help page).