Otothyris lophophanes

Otothyris lophophanes is a highly distinctive loricariid within the otothyrine clade, bearing a unique arrangement of soft, tentacle-like rostral spines or cirri around the snout margin — features reflected in the name lophophanes (bearing a crest or tuft). These projections are unusual among small loricariids and may function as sensory organs or aids in navigating complex substrate surfaces during foraging. The genus Otothyris is restricted to Atlantic Forest coastal river drainages of southeastern Brazil.

In its natural coastal stream habitat, O. lophophanes inhabits rocky, clear-water rivers flowing through Atlantic rainforest from the escarpment to the ocean. These streams have smooth granite and gneiss boulders colonised by algae and biofilm, and the species likely uses its rostral projections to navigate fine surface features while scraping algae with its adhesive disc. Water conditions are moderately soft to hard, clear, and well-oxygenated.

For aquarists, Otothyris lophophanes is among the most morphologically unusual loricariids in this catalogue and represents one of the most compelling targets for specialist catfish collectors. Its facial projections give it a highly distinctive appearance, and its care requirements — smooth rocks, moderate current, clear moderately hard water — are specific but achievable for the experienced keeper. It is essentially never available in the mainstream trade.

Water: Soft to moderately hard at pH 6.0–7.5 and 18–24°C; clear, well-oxygenated water with moderate flow; Atlantic Forest stream conditions. Tank: 40 litres minimum with smooth rocks and boulders as primary decor; moderate directional flow. Feeding: Biofilm and firm algae on rocks primary; supplement with algae wafers pressed onto rock surfaces. Breeding: Not documented. Compatibility: Peaceful with all similar-sized coastal Brazilian species.