Cteniloricaria is a genus of whiptail catfish in the armored suckermouth family Loricariidae, subfamily Loricariinae. Like its relatives Rineloricaria and Farlowella, it shows the group's signature body plan: a flattened, bony-plated trunk that tapers into a long, slender tail, and a ventral sucker-mouth used to grip surfaces and rasp algae and biofilm from submerged wood and stone. The atlas's two species, Cteniloricaria napova and Cteniloricaria platystoma, are confined to the Guiana Shield river systems of French Guiana, Suriname, and Guyana, where whiptails of this kind typically hold station in moderate to swift current over rock and sunken-wood substrate.
Cteniloricaria platystoma, the Flat-mouthed Whiptail, carries a common name that points to the genus's most useful field mark, a wide, flattened snout distinct from the narrower heads of many related whiptails, and it reaches up to 8 in, notably larger than most aquarium-trade Loricariinae. Neither species is a mainstream aquarium fish; whiptail catfish from the Guiana Shield surface only occasionally through specialist importers, and Cteniloricaria in particular is more often seen in ichthyological collections than in home tanks. Where whiptails of this type are kept, the pattern holds across the subfamily: strong water flow, driftwood to graze and to wear down growing tooth structures against, and a diet supplemented with vegetable matter alongside any natural algae growth.