L018 Gold Nugget Pleco 'Rio Xingu' (Baryancistrus xanthellus)

Common Name

Golden Nugget Pleco L018

Scientific name

Baryancistrus xanthellus   |   Origin, Rio Xingu, Pará, Brazil

Origin and Habitat

Endemic to the clear, warm, high oxygen waters of the middle Xingu around Altamira and the Volta Grande, with related forms reported from nearby tributaries such as the Iriri. In the river they cling to rock faces and boulder fields in fast current, duck into crevices during lulls, and graze periphyton on stones and wood. These reaches are seasonally powerful, very well oxygenated, and low in hardness, with rock, cobble, and sand.

Temperature and Water Conditions

Preferred temperature is 79 to 86 F, which is 26 to 30 C. Wild water is typically soft and mildly acidic to near neutral, about pH 6.0 to 7.2. Strong aeration and vigorous surface movement are essential, stability is far more important than chasing exact numbers except for dedicated breeding work. Provide current, high dissolved oxygen, and pristine filtration to mirror the Xingu.

Appearance and Size

Deep black body spangled with bright yellow spots and a bold yellow seam on the dorsal and caudal fins. Juvenile spot patterns vary among L forms, which is why you see trade codes like L018, L081, L085, and L177. Adults commonly reach about 22 cm standard length, roughly 8 to 9 inches total length.

Diet in the Wild

Specialized grazer of periphyton. In nature they spend long periods rasping hard surfaces in fast water and take small invertebrates from biofilm as they graze.

Feeding in Captivity

Offer constant grazing and frequent small meals. Use high quality algae and spirulina wafers, soft wood and stone surfaces with established biofilm, and blanched vegetables such as zucchini, squash, and sweet potato. Add occasional protein such as mysis or chopped bloodworm, but keep the menu plant heavy to avoid digestive issues. Strong flow helps keep food fresh on surfaces and encourages natural rasping behavior.

Behavior and Tank Setup

Generally peaceful with other species, yet territorial with similar loricariids. Provide a long tank with powerful aeration, robust filtration, and steady current. Build rock piles and tight slate or ceramic caves, plus shaded overhangs and driftwood for line of sight breaks. Keep water very clean and oxygen rich, and choose tankmates that enjoy warmth and flow such as midwater Xingu characins and sturdy corys that like high oxygen.

Breeding

Cave spawner with male egg guarding, successful in advanced aquaria but still uncommon. Helpful triggers include very warm water near 86 F, high oxygen, strong current, abundant narrow caves, and conditioning with frequent feedings. The male traps the female in a snug cave, guards adhesive eggs, and fans them until hatching. Fry cling to the cave, then begin to graze and accept soft vegetable foods and fine prepared diets. Expect multiple attempts, meticulous cleanliness, and intense aeration.

Quick Facts

• Scientific name: Baryancistrus xanthellus
• L codes: commonly sold as L018, also seen as L081, L085, L177
• Origin: Rio Xingu, Pará, Brazil, fast rocky rapids and boulder fields
• Adult size: about 22 cm standard length, roughly 8 to 9 inches total length
• Temperature: 79 to 86 F (26 to 30 C)
• Wild pH: about 6.0 to 7.2, soft to near neutral water
• Temperament: peaceful with other species, territorial with similar plecos
• Diet: periphyton and algae grazer with small invertebrates
• Breeding: cave spawner with male guard, advanced conditions needed

Tropical Fish Co. Notes

Golden Nuggets are the Xingu on display, bright yellow spots sparkling against black like river stars. Keep them hot, clean, and roaring with oxygen, give them rock stacks and snug caves, and let them graze on real surfaces. Pairing a showy adult with a lively school of Xingu tetras turns any tank into a fast water window, and if you have the patience to chase a spawn you will be joining a small club of keepers who have cracked one of the river’s icons.