The anuran genus Eleutherodactylus occurs in Central and South America, as well as the West Indies, and comprises nearly 700 recognized species. The diversity of Eleutherodactylus makes it difficult to study the genus as a whole; as a consequence, several authors have divided the genus in phenetic species groups. This division is based on similarity and is not necessarily congruent with monophyletic groups within the genus. Nevertheless, species groups can be considered as hypotheses of natural (monophyletic) groups. I focus on the E. orcesi Group, which contains eight species distributed in the paramo and montane forests (3000–4150 m) of Colombia and Ecuador. The main objectives in the present study are to: (1) describe the osteology and osteological variation of the species within the E. orcesi Group, (2) diagnose the group based on osteological characters, and (3) search for homologies that might support the monophyly of the group. Osteological descriptions for the eight species were made from cleared-and-double-stained specimens. To minimize effects of heterochrony and sexual dimorphism, only adult females were examined. To determine the validity of potential synapomorphies of the E. orcesi Group, I examined cleared-and-stained specimens of 135 species of Eleutherodactylus and used published information for another 29 species. The skulls of all the species of the Eleutherodactylus orcesi Group have a large portion of the frontoparietal fontanelle exposed anteromedially. I hypothesize that the presence of an exposed frontoparietal fontanelle is homologous in the E. orcesi Group and supports the monophyly of the group. I discuss the presence of this character in species outside the E. orcesi Group and hypothesize that in those species the exposed fontanelle was acquired independently. I provide a list of diagnostic characters for the E. orcesi Group and discuss the variation of some of these characters in relation to the general pattern of morphology found in the genus Eleutherodactylus and other anurans. Finally, I discuss intraspecific variation in several osteological characters of the cranium and postcranium of species of the E. orcesi Group, especially E. racemus.