Původní popis
Jordan, D. S. & Gilbert, C. H. 1880. Description of two new species of flounders (Parophrys ischyrus and Hippoglossoides elassodon), from Puget's Sound. Proceedings of the United States National Museum v. 3 (no. 147): 276-279.
Použitá literatura
Fricke, R., Eschmeyer, W. N. & Van der Laan, R. (eds). 2024. Eschmeyer's catalog of fishes: Genera, species, references. World Wide Web.