Dekeyseria is a genus of armored suckermouth catfish (family Loricariidae) in the pleco subfamily Hypostominae, found in the Amazon and Orinoco river systems of Brazil, Colombia, and Venezuela. The atlas's 4 species run 5–8.5 in and share the loricariid body plan — bony armor plates, a ventral sucker mouth for gripping rock and wood in current, and a flattened profile suited to holding position against flowing water. The flat-head pleco (Dekeyseria scaphirhynchus) carries this adaptation furthest, with a notably depressed head shape typical of species that live in swift, rocky river stretches.
The Amazon butterfly pleco (D. amazonica) is the genus's best-known aquarium species, prized for a bold, mottled black-and-cream pattern that gives it its common name, and kept much like other mid-size hypostomine plecos: driftwood in the diet, current, and biofilm and algae to graze. D. picta circulates in the trade under its L-number, L052. All four atlas species have some conservation data on record — three Least Concern and one not yet formally assessed — suggesting the genus is not currently a major conservation concern, though as with many Amazonian loricariids, habitat pressure from damming and the aquarium collection trade bears watching.