Fletcher (1979) stated:-
This genus was originally proposed in the Drepanidae, but has since been transferred to the Notodontidae by Kirby, 1892, ibidem 1: 581.
Watson, Fletcher & Nye (1980, Generic Names of Moths of the World) stated:-
R. dorsalis is a form of Phalaena zelica Stoll, 1790, in Cramer, Uitlandsche Kapellen (Papillions exot.) (Aanhangel): 73, pl.16, figs 2-2D.
Rosema was established in the Drepanidae; it was placed in the Notodontidae by Möschler, 1878, Verh. zool.-bot. Ges. Wien 27 (Abh.): 696.
See also: Zelica Hübner, .
Rosema Walker 1855, proposal for conservation and placement on the Official Index of Valid Generic Names in Zoology by Thiaucourt, 1989, Bulletin of Zoological Nomenclature 46 (2) : 124. Rosema Walker, 1855 has precedence over both Rhogalia Hübner,  1816 & Zelica Hübner, 1825.
Typical ROSEMA species were included within the subfamily NOTODONTIDAE: HETEROCAMPINAE by Kitching & Rawlins, in Kristensen (1999), although they also stated that `perhaps species of Rosema near R. deolis, may also be included' [in the subfamily Pygaerinae].
Learn more about Notodontidae in Wikipedia
Search the Biodiversity Heritage Library (BHL) for references to ROSEMA and included species.