Nymphula Schrank, 1802 was treated as a valid genus and brought out of synonymy by Rose & Pajni, 1979, (Nymphulinae, Pyralidae), Annals of Zoology (Agra) 15 (4) : 173.
Fletcher & Nye (1984) stated:-
Nymphula Schrank, 1802, was established for two nominal species, Pyralis potamogalis [Denis & Schiffermüller], 1775, Ankündung syst. Werkes Schmett Wienergegend: 121 footnote, and Pyralis nymphaealis [Denis & Schiffermüller], 1775, ibidem: 121 footnote. At the same time Schrank referred to the listing of the two species on pages 62 and 63 of his work, where he incorrectly attributed potamogalis to Hübner, citing Hübner's text and figure (see below) and placed Phalaena potamogata Linnaeus, 1758, Syst. Nat. (Edn 10) 1: 529, in synonymy; similarly on page 63 he incorrectly attributed nymphaealis to Hübner, citing Hübner's 1796 text and figure (see below) and placed Phalaena nymphaeata Linnaeus, 1758, ibidem 1: 529, in synonymy.
Pyralis potamogalis [Denis & Schiffermüller], 1775, is an unjustified emendation of Phalaena potamogata Linnaeus, 1758; the emendation was adopted by Hübner, 1793, Samml. Vögel Schmett.: 8, pl.28, and again in 1796, Samml. eur. Schmett.6: 19, pl.13, fig.82. Phalaena nymphaealis [Denis & Schiffermüller], 1775, is an unjustified emendation of Phalaena nymphaeata Linnaeus, 1758, and was adopted by Hübner, 1796, ibidem 6: 19, pl.13, fig.85. Phalaena potamogata Linnaeus and Phalaena nymphaeata Linnaeus were established in the Geometridae, where the Linnaean species-group names ended with `aria' or `ata'. When they were transferred to the Pyralidae the endings of the names were emended unjustifiably under the Code, Article 33(a)(ii), to 'alis'.
It is evident from Schrank's description of Phalaena potamogota Linnaeus (=Pyralis potamogalis [Denis & Schiffermüller]) on pages 62 and 63 of his work, and from Hübner's figure that he cited, that both Schrank and Hübner had misidentified Phalaena potamogata Linnaeus and that Phalaena potamogata Linnaeus sensu Hübner, 1793 and 1796, belong to a taxon later named Phalaena stagnata Donovan, 1806, Nat. Hist. Br. Insects 11: 10, pl.363, fig.2.
Moore,  1884-7, Lepid. Ceylon 3: 305, recognized that Hübner and Schrank had misidentified Phalaena potamogota Linnaeus and designated the type-species of Nymphula Schrank, 1802, as `N. stagnata (potamogalis Hübner)' [sic]. Hannemann, 1964, in Dahl, Tierwelt Dtl. (50): 276, and Spiedel, 1981, Atalanta 12 (2): 129, have accepted Moore's designation in the precise terms in which it was made and have adopted Phalaena stagnata Donovan, 1806, as type-species of Nymphula Schrank, 1802.
Thus two different interpretations of the type-species designation are current in the literature of the past twenty years. One is based on Phalaena potamogata Linnaeus sensu Schrank, 1892, the animal that Schrank described and that was illustrated by Hübner, a taxon that was later named Phalaena stagnata Donovan, 1806; the other is based on Phalaena potamogata Linnaeus, 1758, a nominal species that Schrank listed but misidentified.
NYMPHULA was included within the subfamily CRAMBIDAE: NYMPHULINAE by Munroe & Solis, in Kristensen (1999).
Shaffer (pers. comm.) treats NYMPHULA in the CRAMBIDAE: NYMPHULINAE.
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