The redhook myleus, Myloplus rubripinnis, is a medium to large omnivorous fish of the family Serrasalmidae from South America, where found in the Amazon and Orinoco basins, as well as rivers of the Guiana Shield. It is peaceful and schools often, and can grow to a length of 39 cm (15 in). They are also called the redhook silver dollar and are one of the fish referred to as "silver dollars". These fish are capable of delivering serious bites to humans.