Sphenacodon (meaning "wedge point tooth") is an extinct genus of synapsid that lived from about 300 to about 280 million years ago (Ma) during the Late Carboniferous and Early Permian periods. Like the closely related "Dimetrodon", "Sphenacodon" was a carnivorous member of the Eupelycosauria family Sphenacodontidae. However, "Sphenacodon" had a low crest along its back, formed from blade-like bones on its vertebrae (neural spines) instead of the tall dorsal sail found in "Dimetrodon". Fossils of "Sphenacodon" are known from New Mexico and the Utah–Arizona border region in North America.