Nye (1975) stated:-
Agrotis marginalis Walker, 1858, is a junior primary homonym of Agrotis marginalis Walker,  1856, ibidem 10: 339, -Noctuidae, Noctuinae. The objective replacement name is Agrotis marginifera Walker, 1865, ibidem 32: 706, but this is a junior subjective synonym of Agrotis varians Wallengren, 1863, Wien. ent. Monatschr. 7: 147. Ctenusa varians (Wallengren) should be used as the valid name.
ACANTHONYX Hampson is junior homonym of ACANTHONYX Latreille,  1825, Encycl. meth. Hist. nat. 10 (2): 698, -Crustacea. There is no objective replacement name but A. marginalis Walker, 1858, is congeneric with Chalciope carnicolor Hampson, 1902, the type-species of CTENUSA Hampson, 1910. The latter is therefore available for use as a subjective replacement name.
See: CTENUSA Hampson, 1910.
Poole (1989) included ACANTHONYX Hampson, 1902 as a junior synonym of CTENUSA Hampson, 1910.
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