Tongeia ion is a butterfly of the family Lycaenidae. It was described by John Henry Leech in 1891. Tongeia ion closely resembles Tongeia fischeri.
Subspecies T. i. ion western China, Yunnan-Sichuan-Tibet border and also recorded from Thailand. T. i. cratylus (Fruhstorfer, 1915) Sichuan-Tibet border (Batang; Mangkang) T. i. cellariusi (Bollow, 1930) eastern Gansu (Qinling Mts.)
References
Leech, J. H. "New Species of Rhopalocera from western China". The Entomologist. (original description)