Arapaima (Arapaima gigas)

The arapaima, or pirarucu as it is known in Brazil, is one of the largest freshwater fishes in the world (3). Its local name derives from the indigenous words for red and fish, a reference either to the striking red flecks on the scales towards the tail or the reddish-orange colour of the filleted flesh (4) (5) (6). For its huge size, the arapaima is sleek and streamlined with its dorsal and anal fin set well back near the tail on its largely grey to green body (2). In common with other fish belonging to the superorder Osteoglossomorph (bony-tongued fish), the arapaima has a tongue with sharp, bony teeth that together with teeth on the roof of its pallet are involved in disabling and shredding prey (2) (7).
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