nelsoni, Conorhynchos Evermann [B. W.] & Goldsborough [E. L.] 1902:140, Fig. 1 [Bulletin of the U. S. Fish Commission v. 21 [1901]; ref. 14875] Río Usumacinta, at Monte Cristo, Tabasco, Mexico. Holotype: USNM 50001. Paratypes: USNM 52963 [ex USFC 2382] (1). Type catalog: Ferraris & Vari 1992:8 [ref. 19771], Ferraris 2007:53 [ref. 29155]. •Valid as Arius nelsoni (Evermann & Goldsborough 1902) -- (Burgess 1989:169 [ref. 12860]). •Valid as Potamarius nelsoni (Evermann & Goldsborough 1902) -- (Espinosa Pérez et al. 1993:28 [ref. 22290], Castro-Aguirre et al. 1999:157 [ref. 24550], Acero P. 2003:837 [ref. 26998], Marceniuk & Ferraris in Reis et al. 2003:453 [ref. 27061], Nelson et al. 2004:83 [ref. 27807], Kailola 2004:142 [ref. 28108], Miller 2006:171 [ref. 28615], Marceniuk & Menezes 2007:98 [ref. 29031], Ferraris 2007:53 [ref. 29155], Betancur-R. et al. 2007:348 [ref. 29268], Betancur-R. & Willink 2007:826 [ref. 29439], Page et al. 2013:82 [ref. 32708], Marceniuk et al. 2019:440 [ref. 36658], Barrientos et al. 2023:272 [ref. 41235], Marceniuk et al. 2023:20 [ref. 40422], Page et al. 2023:78 [ref. 40505], Quintana 2024:5 [ref. 41186]). Current status: Valid as Potamarius nelsoni (Evermann & Goldsborough 1902). Ariidae: Ariinae. Distribution: Southern North America and Central America: Usumacinta River basin, Chiapas and Tabasco (Mexico) and Guatemala. Habitat: freshwater.