Gymnotus pantanal Fernandes, Albert, Daniel-Silva, Lopes, Crampton, Almeida-Toledo, 2005

Fig. 16

Body elongated and compressed; greatest depth contained 10.5 to 12.5 times in TL; head length 9.9 to 11.1, anal-fin base length 1.2 to 1.3 in LEA; snout length 2.7 to 2.9, horizontal orbital diameter 14.3 to 15.0 and least interorbital width 2.2 to 3.0 in HL. Mouth superior, dentary prognathous. Pectoral fin with 16-18 rays and anal fin with 256-270 rays; transverse series above lateral line with 7 or 8 scale rows. Ground color brown; body with seven to 25 light-beige transverse stripes, spaced apart. Hyaline fins or light-beige, with scattered dark-brown spots (Graça, Pavanelli, 2007).

Maximum total length. 200.0 mm (Graça, Pavanelli, 2007).

Distribution. Paraná-Paraguay system, in Brazil and Paraguay, and río Capare-Mamoré, in Bolívia (Eschmeyer et al., 2017).

Remarks. Gymnotus pantanal is a non-native species from the upper rio Paraná, and its occurrence in the region can be associated with its introduction as a live bait by anglers, or with the filling of the Itaipu Reservoir and the consequent inundation of the Sete Quedas Falls.