|Hydrolycus scomberoides (lower illustration) and Rhaphiodon vulpinus (upper illustration)|
(G. Cuvier, 1819)
The payara, Hydrolycus scomberoides, is a species of dogtooth tetra. This predatory fish is found in the Amazon Basin, where the Tapajós River appears to the eastern limits of its range. It was the first of four species to be described in the genus Hydrolycus.
The payara's most noticeable feature is the two long fangs protruding from its lower jaw. These fangs can be 4 to 6 inches long and are kept in pockets in the skull. Payaras can reach a length of 1.17 m (3.8 ft) and a weight of 17.8 kg (39 lb), although others suggest it only reaches around 30 cm (12 in) and reports of larger specimens are due to confusion with its relatives, especially H. armatus. The payara's diet mainly consist of smaller fish; these are impaled with their sharp teeth and then consumed. Payaras also share the same habitat with butterfly peacock bass (Cichla ocellaris).
In the aquarium
The payara, which is also sold as the saber tooth barracuda, vampire fish, vampire tetra, or saber tusk barracuda, is a popular species for large, aggressive aquariums. It often outgrows its fish tank, which can present a problem to the uneducated aquarist. It is recommended that they be fed live food, such as goldfish. They should be kept with fish that they cannot fit in their mouths, for example: Siamese tigerfish, arowana, garfish, pacus, catfish, and pig-nosed turtle.