Synbranchus marmoratus Bloch, 1795
Fig. 32
Body elongated, snake-shaped; greatest body depth contained 28.0 to 32.0 times in SL; head length 9.0 to 9.3 in SL; snout length 3.3 to 4.3 and least interorbital width 3.7 to 4.2 in HL. Mouth terminal; premaxilla and dentary with several small teeth. Ground color yellowish, dorsum darkgrey or -brown; several dark-grey or -brown spots on body (Graça, Pavanelli, 2007).
Maximum standard length. 550.0 mm (Graça, Pavanelli, 2007).
Distribution. Drainages from Mexico to Argentina.