Farlowella is a genus of twig, or whiptail, catfishes in the family Loricariidae, part of the elongated subfamily Loricariinae; the atlas's records span Brazil, Colombia, Venezuela, Peru, Bolivia, French Guiana, Guyana, and Paraguay. The defining trait of the genus is body shape: an extremely elongated, thin, stick-like body and a long, tapering snout that together make a resting Farlowella almost indistinguishable from a submerged twig or piece of plant debris among driftwood and roots — one of the more effective camouflage strategies in freshwater fish. Like other loricariids they have an armored, plated body and a ventral sucker-mouth used to graze algae and biofilm from wood and rock surfaces in the slow to moderate current of streams and river margins. The atlas covers 31 species with adult sizes from about 4–10 in.
Farlowella has long been a favorite in the planted-aquarium and algae-crew side of the hobby for its camouflage-perfect form and peaceful, unobtrusive grazing habits; species are simply and consistently sold under the common name Twig Catfish or Whiptail Catfish across most of the genus. They do best in mature, well-oxygenated tanks with driftwood present, both for cover and because wood fiber is thought to support digestion in this group as in other Loricariinae, and they are considered somewhat more sensitive to poor water quality than the stockier, more familiar plecos in the hobby. Conservation-wise the genus is a moderate mix: most assessed species sit at Least Concern, but a meaningful share are Data Deficient or Vulnerable, and Farlowella has at least one species each rated Critically Endangered and Endangered.