festivus, Heros Heckel [J. J.] 1840:376 [Annalen des Wiener Museums der Naturgeschichte v. 2; ref. 2064] Rio Guaporé, Mato Grosso, Brazil. No types known. •Valid as Cichlaurus festivus (Heckel 1840) -- (Ovchynnyk 1967:42 [ref. 37559]). •Valid as Mesonauta festivus (Heckel 1840) -- (Ortega & Vari 1986:20 [ref. 9708], Kullander 1986:206 [ref. 12439], Kullander & Silfvergrip 1991:420 [ref. 16014], Schindler 1998:10 [ref. 23480], Britski et al. 1999:151 [ref. 24147], Lasso et al. 2001:101 [ref. 25928], Kullander in Reis et al. 2003:638 [ref. 27061], Sarmiento et al. 2014:129, 189 [ref. 35004], Schindler & Ottoni 2016:86 [ref. 34465], Koerber et al. 2017:81 [ref. 35267], see DoNascimiento et al. 2017:[29] [ref. 35679], Careaga et al. 2020:77 [ref. 37774], Hablützel & Huanto 2020:56 [ref. 37939], Meza-Vargas et al. 2021:28 [ref. 39298], Chan et al. 2023:145 [ref. 40365]). Current status: Valid as Mesonauta festivus (Heckel 1840). Cichlidae: Cichlinae. Distribution: South America: Amazon and Paraguay River basins (Bolivia, Brazil, Paraguay and Peru). Introduced in Hong Kong (China). Habitat: freshwater.