A new darkling beetle species, Corticeus turcicus F. Soldati, sp. nov., is described from six localities in Turkey. The only related species in Europe and the whole Mediterranean basin seems to be C. unicolor Piller & Mitterpacher, 1783 from which it differs by the smaller body size, yellowish coloration, different with ratio between pronotum and elytra and aedeagal morphology. An updated identification key to the currently known Corticeus species of Turkey is proposed and all species are illustrated. The types of Corticeus fusciventris Reitter, 1884 and C. rufobasalis (Pic, 1917) were studied and a new synonymy is established: C. fasciatus (Fabricius, 1790) = C. rufobasalis (Pic, 1917), syn. nov.