Nye (1975) stated:-
Incorrect type-species designation: Noctua filigrama Esper, 1788, a name not, originally included in Polymixis, cited by Hampson, 1905, Cat. Lepid. Phalaenae Br. Mus. 5: 60. Hampson (on page 198) listed 'Noctua polymita, Hübn., , Eur. Schmett., Noct. f. 48 (1827) nec Linn.' as a junior synonym of N. filigrama Esper, 1788. However, Hübner,  when he proposed Polymixis was including the true polymita Linnaeus, for he had by then realised that his polymita of : fig. 48 was a misidentication. Hübner renamed this fig. 48 as Xanthopastis flavivibica on page 211 of his Verzeichniss.
Eremophysa Boursin, 1958 was downgraded to denote a subgenus of Polymixis Hübner,  1816 by Hacker and Ronkay, 1992, Esperiana 3 : 477. Eremophysa was treated in the Noctuidae, Acronictinae/Amphiphyrinae by Nye, 1975 Generic Names Moths World, Vol 1 : 185 and is now placed in the Noctuidae, Cuculliinae as a subgenus of Polymixis.
Eumichtis Hübner, 1821 was downgraded to denote a subgenus of Polymixis Hübner,  1816 by Hacker and Ronkay, 1992, Esperiana 3 : 477.
Poole (1989) included CRYPSEDRA Warren, 1910; PROPOLYMIXIA Berio, 1980; and SIMPLITYPE Berio, 1980 as junior synonyms of POLYMIXIS Hübner, 1820.
Poole (1989) included 37 species in the genus POLYMIXIS.
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