Widely-distributed throughout the Amazon, Orinoco, Essequibo, and Tocantins river systems in Brazil, Peru, Bolivia, Ecuador, Colombia, Venezuela, and Guyana.

Type locality is ‘Rio Cupai [= Rio Cupari], Rio Tapajós basin, Amazon River drainage, Pará State, Brazil’.

Known only from the lower Amazon river basin, and possibly restricted to the Xingu and Tocantins watersheds.

Type locality is ‘ Rio Santa Teresa, a western tributary of upper Rio Tocantins, Goiaz State, Brazil’, referring to what is now known as Goiás state, central Brazil.

This species is relatively rare in the hobby but sometimes available from specialist retailers or private breeders. Though described in 1991 it was first collected much earlier and misidentified by Gosse (1976) as G. surinamensis.

It’s one of just five Geophagus species not to be included in the nominal G. surinamensis ‘group’ of closely-related species within the genus along with G. gottwaldi, G. grammepareius, G. harreri an…

Prior to description in 2011 this species was traded under the DATZ code numbers L018, L085, L077 and ‘Das Aquarium’ code LDA060, while a very similar-looking fish from the lower rio Xingu which has been assigned the code L081 may also represent a form of B. xanthellus but is not mentioned in the description paper.

B. xanthellus can be distinguished from congeners by a combination of the following…

Prior to description this species was traded under the DATZ code L047 or the alternative vernacular name ‘magnum pleco’. It can be distinguished from congeners by a combination of the following characters: presence of a broad, light-coloured (usually yellowish) distal band on the dorsal and caudal fins throughout life, slightly reduced in adults. The only other member of the genus to possess such bands is B. xanthellus but in that species they are reduced to small markings at the fin tips in adults, and the body is covered in pale, normally yellowish, spots.

The precise extent of this species’ range is unclear. The majority of records pertain to the lower rio Xingu basin in the state of Pará, northern Brazil, including middle and lower reaches of its major tributary the rio Iriri, although the type locality is in Mato Grosso state several hundred kilometres upstream.

There also exist a handful of records from the rio Jamanxim (a major affluent of the rio Tapajós which drain…

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…