Fletcher & Nye (1982) stated:-
Kirby cited as type-species Sphinx nessus Drury, 1773, a nominal species not originally included in Theretra. At the same time, however, Kirby placed nessus as a senior synonym of equestris, a nominal species originally included in Theretra. Under the Code, Article 69(a)(iv), this designation constitutes the fixation of the originally included nominal species as the type-species.
S. equestris is a junior subjective synonym of Sphinx nessus Drury, 1773, Illust. nat. Hist. exot. Insects 2: 46, index, pl.27, fig.1.
THERETRA was included within the subfamily SPHINGIDAE: MACROGLOSSINAE by Lemaire & Minet, in Kristensen (1999).
Kitching & Cadiou (2000) list FLORINA Tutt, 1903; GNATHOSTYPSIS Wallengren, 1858; HATHIA Moore, 1882 and OREUS Hübner, 1819 as junior synonyms of THERETRA Hübner, 1819.
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