Citrogramma difficile (Curran)
Curran (1928) questioned validity of C. difficile as a different species and pointed out the possibility that it could be a synonym of C. gedehanum.
Synonyms: Syrphus difficilis Curran, 1928, 1931a: 313 (key); Citrogramma difficile of Vockeroth, 1969: 95 (comb. nov.); Knutson et al., 1975: 311 (cat. cit.); Citrogramma difficilis of Wyatt, 1991: 155 (cit.), 158 (ident. key), 163 (descr.).