Ancistrus is a genus of nocturnal freshwater fish in the family Loricariidae of order Siluriformes, native to freshwater habitats in South America and Panama. Fish of this genus are common in the aquarium trade where they are known as bushynose or bristlenose catfish. In the aquarium hobby they are often referred to as bushynose or bristlenose plecos instead, but this may lead to confusion as "pleco" usually is used for Hypostomus plecostomus and its allies and is often used as a catchall term for any loricariids remotely resembling that species.
Taxonomy
The type species is Ancistrus cirrhosus. This genus is the largest genus within the tribe Ancistrini. The genera Pristiancistrus, Thysanocara and Xenocara are now synonyms of Ancistrus. Tentacules, tentacles directly associated with odontodes, develop on the pectoral fin spine of the males of some species. In comparison with a typical loricariid (pleco), a bristlenose is typically shorter (4–6 inches or 15 cm or less), more flattened and fatter with a comparatively wider head. Colouration is typically mottled brown, grey or black. Small white or yellow spots are common.
Distribution and habitat
Ancistrus is one of the widest ranging Loricariid genera, and representatives are found in most areas where the family in general is present. These are the only known loricariids that possess adaptions for a subterranean lifestyle, such as reduced pigmentation (appearing overall whitish) and eyes.
Species
Ancistrus contains the following valid species: