A new species of Crocuta (spotted hyenas), Crocuta eturono n. sp., from the Early Pliocene of the Turkana Basin, Kenya is described. The species has been recovered from LO6S, a site in the Kataboi Member of the Nachukui Formation, on the western side of Lake Turkana. The site is dated to >3.4 Ma. The new species differs from all previously identified species of Crocuta in its length proportions of the cheek teeth, having a very long m1 and short p3 and p4. The species is also tentatively identified from the Tulu Bor Member of the Koobi Fora Formation, east side of Lake Turkana. The new species provides information for a discussion of the structure of the hyena guild in eastern Africa 4–3 Ma. Three groups of taxa are identified with distinct distributions. It is hypothesized that specific ecomorphologies of each group account for these distinctions.