Fletcher (1979) stated:-
P. glaucans was proposed by Stoll as the objective replacement name for Phalaena glauca Stoll, 1781, in Cramer, ibidem 4: 152, 249, pl.368, fig.D, a junior primary homonym of Phalaena glauca Cramer, 1777, ibidem 2: 17, 149, pl.107, fig.E. The type-species was included by Walker and designated by Hampson as glauca Cramer, an incorrect authorship. Attention to this synonymy was drawn by Prout, 1929, Treubia 7: 445 (footnote).
This genus was originally proposed in the Lithosiidae (now Arctiidae), but has since been transferred to the Geometridae; its first published use in this family appears to have been by Butler, 1881, Ann. Mag. nat. Hist. (5) 8: 381.
Parsons et al. (1999) included BIZARDA Walker, 1865 [February]; and CNISSOCNEMA Bryk, 1913 as junior synonyms of MILIONIA Walker, 1854 [May 13].
Parsons et al. (1999) included 86 species and 40 subspecies (inc. nominates) in the genus MILIONIA.
Learn more about Geometridae in Wikipedia
Search the Biodiversity Heritage Library (BHL) for references to MILIONIA and included species.