Gymnotus paraguensis Albert, Crampton, 2003

Fig. 16

Body elongated and compressed; greatest depth contained 9.7 to 10.2 times in TL; head length 7.5 to 8.2, anal-fin base length 1.2 in LEA; snout length 2.8 to 3.0, horizontal orbital diameter 13.9 to 15.4 and least interorbital width 2.4 to 3.2 in HL. Mouth superior, dentary prognathous. Pectoral fin with 17-21 rays and anal fin with 260-270 rays; transverse series above lateral line with 11 or 12 scale rows. Ground color dark-brown; body with 23-26 light-beige oblique stripes, with well-defined margins; two to seven inverted Y-shaped stripes, or sometimes X-shaped, or sometimes interrupted on porterior half of body. Hyaline fins or light-beige, with scattered dark-brown spots (Graça, Pavanelli, 2007).

Maximum total length. 280.0 mm (Graça, Pavanelli, 2007).

Distribution. Paraná-Paraguay system.

Remarks. Gymnotus paraguensis 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.