A relatively slender-bodied species, Orestias gloriae is clearly distinguished from all other species of Orestias by the following unique characters: (1) The lyre-shaped pattern of dorsal neuromasts, which is characteristics of Orestias is reduced to the rostral and anterior supraorbital lines formed by small neuromasts followed caudally by few and large isolated neuromasts, which are irregularly placed. (2) The infraorbital line of neuromasts is represented by a discontinuous series of few small neuromasts. (3) The supraorbital line of neuromasts is not connected with both the infraorbital and preopercle-mandibular lines. (4) The skull roof is covered by thick, irregularly-shaped cycloid scales some of which bear marked ridges, whereas other lack ornamentation. (5) The large, irregularly-shaped scales covering the posterior part of the skull roof are ankylosed to each other into a thin, rigid plate. In addition, O. gloriae presents a protractile upper jaw reaching one-third of the head length when extended. This value is higher than those found in other species of Orestias with protactibility and inhabiting the southern Chilean Altiplano. The new species has 29-31 vertebrae, a value that represents the lowest range among species of Orestias (Ref. 89071).