Idiognathoides is an extinct genus of conodonts. Glen K. Merrill stated in 1963 that "conodont workers have considered Idiognathoides to be a junior synonym of Polygnathodella but it now proves to be a junior synonym of Cavusgnathus. Polygnathodella and Cavusgnathus are shown to form a transitional series."
Species taxanomy provided by GBIF Secretariat (2022). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org on 2023-06-13; License: CC BY 4.0