chalceus, Tetragonopterus Spix [J. B. von] & Agassiz [L.] 1829:70, Pl. 33 (fig. 1) [Selecta genera et species piscium quos in itinere per Brasiliam; ref. 13] Rivers of equatorial Brazil [= lower Amazon basin]; mouth of Uruará canal to Amazon River, at Vira Sebo community, Canaã Village, Prainha City, 01°53’33''S, 53°29’17''W (Pará State, Brazil). Syntypes: MHNN 785 (1). Type catalog: Kottelat 1988:84 [ref. 13380] with potential holotype. Comments on type locality see Koerber 2021:93 [ref. 38172]. •Valid as Tetragonopterus chalceus Spix & Agassiz 1829 -- (Ortega & Vari 1986:10 [ref. 9708], Géry et al. 1991:58 [ref. 21021], Taphorn 1992:343 [ref. 23654], Planquette et al. 1996:320 [ref. 22818], Reis in Reis et al. 2003:212 [ref. 27061], Benine et al. 2004:339 [ref. 27973], Zarske & Géry 2006:8 [ref. 29010] with author as Agassiz, Melo et al. 2011:49 [ref. 31233], Silva & Benine 2011:50 [ref. 31347], Silva et al. 2013:1629 [ref. 32576], Araujo & Lucinda 2014:314 [ref. 33377], Barriga Salazar 2014:109 [ref. 35745], Sarmiento et al. 2014:53, 185 [ref. 35004], Melo et al. 2015:711 [ref. 35424], Silva et al. 2016:15 [ref. 34929], DoNascimiento et al. 2017:52 [ref. 35633], Careaga et al. 2020:75 [ref. 37774], Koerber 2021:92, 93 [ref. 38172], Meza-Vargas et al. 2021:20 [ref. 39298], Borstein et al. 2022:16 [ref. 39507], Koerber et al. 2022:39 [ref. 39235], Taphorn et al. 2022:19 [ref. 41297]). Current status: Valid as Tetragonopterus chalceus Spix & Agassiz 1829. Characidae: Tetragonopterinae. Distribution: South America: Amazon and Orinoco river basins (Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname and Venezuela). Habitat: freshwater.