Copris ajax Sturm, 1826: 125 . Unavailable name (Nomen nudum).

Nomenclatural history: This name was published in the first edition of the catalogue of beetles present in the collection of Jacob Sturm. Sturm (1826) listed ‘ Ajax St. ’, from ‘ Brasilia ’, as the first species of genus Copris, but he gave no description for his new taxon. In the second edition of his collection’s catalogue, however, Sturm (1843) listed ‘ Ajax . St. Cat.’ as one of the synonyms of Phanaeus ensifer, fact that suggests that Sturm was not aware of Germar’s description of this latter name when he published the first edition of his catalogue. Since then, Copris ajax was always cited as junior synonym of C. ensifer (e.g., Harold 1869; Nevinson 1892; Gillet 1911; d’Olsoufieff 1924; Blackwelder 1944; Edmonds & Zidek 2010), but, as this name was never published companied by a description, illustration or an indication as defined in Article 12 of the Code, it does not satisfy the criteria of availability and is here considered as an unavailable name.