A species of the dugongine dugongid genus Rytiodus from the Miocene (Burdigalian—Langhian; 19–14 Ma) deposits of Jabal Zaltan (= Gebel Zelten), Libya, is re-described, considered a valid species differing from Rytiodus capgrandi from the lower Miocene (Aquitanian) of the Aquitaine Basin (SW France), and named Rytiodus heali. R. heali, together with R. capgrandi and Corystosiren varguezi appear to constitute a taxon of dugongines characterized by broad, mediolaterally compressed, blade-like tusks with enamel mainly on the medial side, and a modified nasal process of the premaxilla. They are regarded as specialized seagrass feeders, using their tusks in excavation of seagrass rhizomes. Rytiodus lived sympatrically with the generalist small-tusked halitheriine dugongid genus Metaxytherium.