However, the first description of a "Dimetrodon" fossil came a year earlier, when Cope named the species "Clepsydrops limbatus" from the Texas Red Beds. (The name "Clepsydrops" was first coined by Cope in 1875 for sphenacodontid remains from Vermilion County, Illinois, and was later employed for many sphenacontid specimens from Texas; many new species of sphenacodontids from Texas were assigned to either "Clepsydrops" or "Dimetrodon" in the late nineteenth and early twentieth centuries.) "C. limbatus" was reclassified as a species of "Dimetrodon" in 1940, meaning that Cope's 1877 paper was the first record of "Dimetrodon".