Western Atlantic: estuarine areas of the Orinoco (Venezuela), Corantijn (Suriname), Oyapock, Amazon and Grajaú (Brazil) rivers, and from marine areas under influence of these rivers
Definition: length from the tip of the snout to the tip of the longer lobe of the caudal fin, usually measured with the lobes compressed along the midline. It is a straight-line measure, not measured over the curve of the body