jenynsii, Solea Günther [A.] 1862:476 [Catalogue of the fishes in the British Museum v. 4; ref. 1969] Río de la Plata, Buenos Aires, Argentina. Holotype (unique): BMNH 1917.7.25.3 (skin). Based on literature sources. •Valid as Achirus jenynsii (Günther 1862) -- (Gómez & Chebez 1996:66 [ref. 23791] as jenynsi). •Valid as Catathyridium jenynsii (Günther 1862) -- (Sverlij et al. 1998:79 [ref. 27632] as jenynsi, Britski et al. 1999:154 [ref. 24147], Ramos in Reis et al. 2003:667 [ref. 27061], López et al. 2003:79 [ref. 27366], Ramos in Menezes et al. 2003:107 [ref. 27192], Menni 2004:88 [ref. 28131] as jenynsi, Litz & Koerber 2014:36 [ref. 33622], Sarmiento et al. 2014:189 [ref. 35004], Mirande & Koerber 2015:59 [ref. 35117], Bertaco et al. 2016:426 [ref. 34561], Nión et al. 2016:55 [ref. 35565], Koerber et al. 2017:82 [ref. 35267], Reis et al. 2020:471 [ref. 38364], Bitencourt et al. 2022:4 [ref. 39848], Loureiro et al. 2023:175 [ref. 40506]). Current status: Valid as Catathyridium jenynsii (Günther 1862). Achiridae. Distribution: South America: Paraná and Uruguay River basins (Argentina, Brazil, Bolivia, Paraguay and Uruguay). Habitat: freshwater.