The scissor-tailed hummingbird is the only member of its genus and has no subspecies. A proposal in the early 21st century to move it into genus Eugenes was not adopted by major worldwide taxonomic systems.Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 31 January 2022. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved February 1, 2022Clements, J. F., T. S. Schulenberg, M. J. Iliff, S. M. Billerman, T. A. Fredericks, J. A. Gerbracht, D. Lepage, B. L. Sullivan, and C. L. Wood. 2021. The eBird/Clements checklist of Birds of the World: v2021. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ Retrieved August 25, 2021
