Brachyhypopomus is a genus of fish in the family Hypopomidae (bluntnose knifefish) native primarily to tropical and subtropical South America (south to the Río de la Plata Basin), although a single species, B. occidentalis, also occurs in Panama and Costa Rica.

[1][2] They are found in a wide range of static or slow-flowing freshwater habitats such as edges of rivers, streams, floodplains and swamps, but they are absent from deep river channels (a habitat of many other knifefish).

[2] They are small to medium sized knifefish, reaching up to 12–46 cm (4.7–18.1 in) in total length depending on the species involved.

[1][2] Overall the various species are similar in general shape, but they do differ in morphometrics and meristics.

They vary in general color and pattern, but are well-camouflaged and typically brownish.