mercedarius, Synbranchus Weyenbergh [H.] 1877:22, Pl. 4 [Actas de la Academia Nacional de Ciencias Exactas, Buenos Aires. v. 3 (no. 1); ref. 14248] Lakes along Río Primero, near Cordoba and Chacra de la Merced, Argentina. Syntypes: (several) MSNG. •Synonym of Synbranchus marmoratus Bloch 1795 -- (Rosen & Greenwood 1976:55 [ref. 7094], Kullander in Reis et al. 2003:594 [ref. 27061], Litz & Koerber 2014:32 [ref. 33622], Mirande & Koerber 2015:54 [ref. 35117], Koerber et al. 2017:75 [ref. 35267]). Current status: Synonym of Synbranchus marmoratus Bloch 1795. Synbranchidae. Habitat: freshwater, brackish.