Heterotis Rüppell [W. P. E. S.] (ex Ehrenberg) 1829:10 (footnote) Masc. Sudis niloticus Cuvier 1829. Type by monotypy. On Official List (Opinion 1132); gender given as masculine by ICZN but is classically feminine. Ruled by ICZN to be available from publication in synonymy by Rüppell. Previously credited to Ehrenberg 1836:432 [ref. 5036]. •Valid as Heterotis Rüppell 1829 -- (Daget 1984:57 [ref. 6170], Lévêque et al. 1989:114 [ref. 26480], Paugy & Bénech 1989:299 [ref. 26478], Paugy in Lévêque et al. 1990:114 [ref. 21589], Poll & Gosse 1995:97 [ref. 24781], Dankwa et al. 1999:13 [ref. 28023], Hilton 2003:90 [ref. 26584], Fricke et al. 2018:28 [ref. 35805]). Current status: Valid as Heterotis Rüppell 1829. Arapaimidae.