Gymnotus inaequilabiatus Valenciennes 1847

Gymnotus inaequilabiatus Valenciennes, 1847 Figure 15, Table 2 Material examined: Argentina: MACN 5979, 250 mm, Rosario, Río La Plata (~ 32°56’S, 060°38’W); MLP 3353, 250 mm, Misiones, Río Paraná (~ 26°49’S, 055°00’W); MNHN 4615 (neotype), 920 mm (600 mm according to the original description, 850 mm according to the label), Argentina, Buenos Aires, Rio de La Plata (~30°40’S, 058°30’W according to MNHN database or ~34°37’S, 058°23’W). Brazil, Mato Grosso: LBP 12616, ~ 650 mm, Corumbá, Rio Paraguai drainage, Rio Cuiabá (~ 18°09’S, 057°33’W). Brazil, Mato Grosso do Sul: MCP 15818, 535 mm, Rio Paraguai near Cáceres; USNM 1643, 791 mm, Rio Paraguai drainage (~ 17°53’S, 057°29’W). Brazil, Rio Grande do Sul: MCP 6059 (3), 173–355 mm, Iraí, Rio Uruguai drainage, Sanga das Águas Frias, 100 m from Rio Uruguai (27°12’00”S, 053°16’60”W); MCP 6956, 602 mm, Rio Uruguai at Santana Velha, near Uruguaiana (~ 29°45’S, 057°50’W); MCP 19552 (3), 145–336 mm, Rosário do Sul, pool next to Olaria in the floodplain along Rio Santa Maria, North side of BR290 (30°14’16”, 054°53’33”W); MCP 31177, 560 mm, Roque Gonzales, Rio Uruguai drainage, Rio Ijuí near small hydroelectric power station (PCH) Pirapó (~ 28°30’S, 055°10’W); MCP 39375, 550 mm, same locality as MCP 31177; UFRGS 14457, 498 mm, (~27°11’S, 053°06’W). Brazil, Santa Catarina: MCP 19044, 440 mm, Itá, Rio Uruguai, Rio do Engano, road between Itá and Seara (27°08’60”S, 52°13’00”W); MCP 20683, 410 mm, Itapiranga, Rio Uruguai, near Fortaleza (27°11’42”S, 053°38’34”W). Brazil, São Paulo: MZUSP 22246 (3), 130–282 mm, Represa do Boa, Corumbataí, Rio Paraná drainage, Rio Tietê (~ 21°46’S, 048°58’W); MZUSP 22862, 238 mm, Corumbataí, Rio Paraná drainage, Rio Tietê, Lagoa Ponte Seca (~ 21°46’S, 048°58’W); MZUSP 46001, 998 mm, Rio Paraná drainage, Porto Primavera (~ 22°31’S, 053°10’W). Diagnosis. Gymnotus inaequilabiatus differs from all sympatric members of the Gymnotus tigre clade (G. paraguensis) on the following characters: 1, more precaudal vertebrae (45 in all specimens vs. 32–35, median 34); 2, fewer ventral lateral-line rami (VLR 23–38, median 32 vs. 49–55, median 50). Gymnotus inaequilabiatus further differs from sympatric Gymnotus species on the following characters: 1, total length (max. 998 mm vs. max. 419 mm in G. c. australis and max. 305 mm in G. cuia the next two largest species); 2, a color pattern characterized by 21–29, mode 22 obliquely-oriented, chocolate-colored bands in juveniles (