orthonops, Hemiodus Eigenmann [C. H.] & Kennedy [C. H.] 1903:511 [Proceedings of the Academy of Natural Sciences of Philadelphia v. 55; ref. 1260] Arroyo Trementina, Paraguay. Holotype: CAS 61476 [ex IU 9955]. Paratypes: (5) CAS 61477 [ex IU 9958] (1), CAS 61478 [ex IU 9959] (2, 1 dissected), FMNH 52573 (1), ZMB 16959-61 (1, 1, 1). Type catalog: Ibarra & Stewart 1987:45 [ref. 12367]. •Valid as Hemiodus orthonops Eigenmann & Kennedy 1903 -- (Gómez & Chebez 1996:54 [ref. 23791], Britski et al. 1999:71 [ref. 24147], Langeani in Reis et al. 2003:98 [ref. 27061], López et al. 2003:16 [ref. 27366], Menni 2004:71 [ref. 28131], Sarmiento et al. 2014:186 [ref. 35004], Mirande & Koerber 2015:10 [ref. 35117], Koerber et al. 2017:12 [ref. 35267], Nogueira et al. 2019:802 [ref. 36655], Nogueira et al. 2020:[5] [ref. 38050], Reis et al. 2020:462 [ref. 38364]). Current status: Valid as Hemiodus orthonops Eigenmann & Kennedy 1903. Hemiodontidae. Distribution: South America: Paraguay and Paraná River basins (Argentina, Brazil, Bolivia and Paraguay). Habitat: freshwater.