alterum, Pygidium Marini [T. L.], Nichols [J. T.] & LaMonte [F. R.] 1933:2, Fig. 2 [American Museum Novitates No. 618; ref. 2889] La Rioja, Río de Los Sauces, Argentina. Holotype: AMNH 12241. Paratypes: AMNH 12242 (3). Type catalog: Ferraris 2007:415 [ref. 29155]. •Valid as Trichomycterus alterum (Marini, Nichols & LaMonte 1933) -- (Arratia & Menu-Marque 1984:515 [ref. 8254], Burgess 1989:321 [ref. 12860], Fernández 2000:32 [ref. 26195]). •Valid as Trichomycterus alterus (Marini, Nichols & LaMonte 1933) -- (Fernández 2000:352 [ref. 25077], Fernández & Vari 2002:743 [ref. 26231], López et al. 2002:60 [ref. 26808], de Pinna & Wosiacki in Reis et al. 2003:279 [ref. 27061], López et al. 2003:39 [ref. 27366], Menni 2004:82 [ref. 28131], Fernández & Osinaga 2006:387 [ref. 28738], Ferraris 2007:415 [ref. 29155], Fernández & Vari 2009:198 [ref. 30062], Sarmiento et al. 2014:193 [ref. 35004], Fernández et al. 2015:9 [ref. 35041], Mirande & Koerber 2015:37 [ref. 35117], Fernández & Andreoli Bize 2018:366 [ref. 36232]). Current status: Valid as Trichomycterus alterus (Marini, Nichols & LaMonte 1933). Trichomycteridae: Trichomycterinae. Distribution: Argentina and Bolivia. Habitat: freshwater.