The Gold Nugget Pleco (Baryancistrus xanthellus) is one of the most coveted and visually arresting plecos available to freshwater aquarists. Native exclusively to the Rio Iriri, a tributary of the Rio Xingu in Brazil, it inhabits fast-flowing, warm, extremely well-oxygenated rocky rivers. Its body is jet black, densely covered with vivid yellow spots of uniform size, and its dorsal and caudal fins are trimmed with a bold yellow-orange border, creating an unmistakable and spectacular appearance. Multiple L-number designations exist for this species (L018, L081, L177), reflecting natural geographic color variations in spot size and border width. Growing to approximately 25 cm, the Gold Nugget is a sizeable pleco requiring a large aquarium. It is endemic to a specific stretch of river that has been significantly impacted by dam construction in Brazil, making captive specimens increasingly important. In the aquarium, it requires very warm water, high oxygenation, strong current, and soft to moderately hard, slightly acidic to neutral water. It is an omnivore that feeds primarily on biofilm, algae, and organic matter attached to rocks and wood, but also requires protein-rich supplemental feeding. The Gold Nugget is peaceful toward other species but can be territorial with conspecifics in limited space. It is an intermediate-level fish due to its specific environmental demands.
