With specimens caught at a length of 120 cm (47 in) and a weight of up to 40 kg (88 lb), this species of Hoplias is the largest. The largest rod and reel record stands at 101 cm (40 in). This species has an elongated cylindrical shape and is typically brown in color with a lighter base color, although shades can vary. The body has a number of vertical patches or stripes and small spots are visible on the upper anterior part of the body, including the head. The fish's patterning can vary geographically, ranging from almost solid black to pale brownish-gold with marked dark stripes. While this species may seem docile, it has been known to attack divers and swimmers, although fatal incidents are rare.