4: 234, pl.398, figs F, G.
Fletcher & Nye (1982) stated:-
P. firmiana was incorrectly attributed to Cramer, both by Hübner and by Grote.
Hygrochora was established in the Geometridae; it was placed in the Notodontina, now Notodontidae, by Herrich-Schüffer,  1850-1858, Samml. neuer oder wenig bekannter aussereur. Schmett. 1: 66; in the Bombycidae by Kirby, 1892, Synonymic Cat. Lepid. Heterocera 1: 721 (but attributed to Herrich-Schüffer, an incorrect authorship); the type-species was placed in the Bombycidae Zanolinae, now Apatelodidae, by Draudt, 1929, in Seitz, Gross-Schmett. Erde 6: 696. Hygrochroa Hübner, , is a senior subjective synonym of Apatelodes Packard, 1864, but has not been used during the last eighty years. Under the Code, Articles 23(a-b) and 79, the case should be referred to the Commission to use its plenary powers in the interest of nomenclatural stability to grant nomenclatural precedence to Apatelodes Packard, 1864, over Hygrochroa Hübner, . Incorrect type-species designation: Hygrochroa ficus Herrich-Schüffer, , a nominal species not originally included in Hygrochroa, and not linked with one of the originally included nominal species when designated by Kirby, 1892, Synonymic Cat. Lepid. Heterocera 1: 721.
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