Carterocephalus skada (Edwards, 1870), formerly treated as a synonym of the subspecies
Papilio palaemon mandan (Edwards, 1863) [3982], is raised to full species with
magnus Mattoon & Tilden, 1998 as a subspecies in Zhang et al. (2020)
(1).
C. palaemon (Pallas, 1771) is now considered extralimital to North America.