Fins - D1 - VI, none filamentous; D2 - 10(9-11); pectoral fin rays 16 (15-17); anal - 10(9-11); pelvic disk shaped I,5
Head - Males' jaws either long or short; jaw lengths differ greatly between long jawed males and females;
Color - Have 6-8 grayish vertical trunk bars extending from behind pectoral base to slightly anterior to hypural base; first dorsal fin red to reddish orange in life, especially prominent in males.
Distribution - Colombia to Brazil; South America from Rio Magdalena to Belem, Brazil
Habitat - Usually reported from estuaries and river deltas over sand and mud bottoms, seldom in water of much flow and has never been reported in freshwater above tidal influence. The only occasion adults have been collected in shallow flowing water is during reproduction.