In the Amazon region it is only specimens larger than around 160 cm and werighing in excess of 50 kg that are referred to as ‘Piraíba’ with the name ‘filhote’ normally applied to smaller individuals. Other vernacular names include ‘Salton catfish’, ‘Kumakuma’; and ‘tiger antenna catfish’; with members of the genus often referred to collectively as ‘goliath catfishes’.

In the aquarium hobby the name Hyphessobrycon stegemanni has frequently been misapplied to a species that has been described as Hemigrammus ataktos Marinho, Dagosta, & Birindelli 2014. The reasons for this confusion are presumably that the two occur sympatrically in the rio Tocantins system and both possess a dark lateral stripe on the body.

This species is occasionally available in the aquarium trade, although usually as bycatch among shipments of other fishes.

It is sometimes traded as H. sp. ‘Araguaia red’, H. sp. ‘Araguaia’ or ‘Schultz’s tetra’.

Its name appears to have been misapplied to similar-looking fishes occurring throughout much of the middle and lower Amazon in Brazil and Colombia, plus the rio Orinoco drainage in Colombia and Venezuela, and coastal systems of the Guianas. Some of these have been described as distinct species (e.g. Hyphessobrycon amapaensis Zarske & Géry 1998; H. eschwartzae García-Alzate, Román-Valencia & Ortega 2013; H. montagi Lima, Couthino & Woziacki 2014), whereas the identity of others remains un…

Type locality is ‘Rio das Mortes, some 100 km before its confluence with the Braço Maior of the Rio Araguaia (the western border of the Isla do Bananal). State of Mato Grosso.’

The das Mortes is a principal tributary of the Araguaia, itself the major affluent of the rio Tocantins within the lower Amazon basin in central and western Brazil, although the full range of H. amandae within the Araguaia system is unclear.

Metynnis lippincottianus is occasionally seen for sale, sometimes under the name of "Silver Dollar". It is easily distinguishable from m. argenteus and m. hypsauchen (which are more commonly sold as Silver Dollars) by its spotted pattern, hence the common name. M. lippincottianus shares a common name with m. maculatus but the two can be distinguished as the spots on m. maculatus are more pronounced.

Silver dollars are common and popular fish in the hobby. They are related to piranh…

Despite the ubiquity of its name in aquarium literature, confusion surrounds its true identity. Given it’s the only member of the genus occurring on the island, fish from Trinidad do presumably represent C. aeneus (see our image), but the classification of those from other localities appears far from certain.

Today the species is accepted to occur throughout much of South America, and indeed similarly-patterned fish do occur across a large portion of the continent. Some of these, such as the gree…