Desana Corydoras

Geographical Origin and Habitat: This species has an extremely restricted range and is endemic to the upper Rio Negro basin, specifically the Igarapé Castanha, a tributary of the Rio Tiquié in Amazonas State, Brazil. It inhabits small blackwater streams characterized by warm, extremely soft, and acidic water, with slow to moderate currents and sandy bottoms covered with decomposing leaf litter.

Taxonomy and Morphology: Belonging to the family Callichthyidae, subfamily Corydoradinae. Described scientifically in 2017 by Lima and Sazima, this species was previously known in the aquarium hobby by the code CW011. It features the typical Corydoras body shape, protected by overlapping bony plates instead of scales, and a downward-facing mouth equipped with sensory barbels. It reaches about 5 cm in length.

Social Behavior: It is a peaceful, gregarious, bottom-dwelling fish that must be kept in groups of at least 6-8 specimens. A fascinating biological aspect is its mimicry of Corydoras tukano; sharing the same habitat, the less common Corydoras desana blends into schools of C. tukano for predator protection. Like other Corydoras, it has intestinal respiration allowing it to gulp air.

Coloration and Sexual Dimorphism: The body has a light beige or golden ground color, marked by a prominent dark longitudinal stripe running along the flank to the tail base, and a characteristic dark rounded patch under the dorsal fin. The dorsal fin often has dark pigmentation on the front. No visible sexual differences exist except that mature females are rounder and larger.

Aquarium Setup: Requires a species-specific or community aquarium of at least 80 liters (approx. 20 gallons). It is of critical importance to use a substrate of fine, rounded sand, as sharp gravel can damage or erode their delicate sensory barbels during foraging. Furnish the tank with driftwood, roots, and dry Indian almond leaves (Catappa) to create shaded areas.

Diet and Feeding: Lighting should be dim or filtered through floating plants (such as Pistia or Limnobium) to make the fish feel secure and encourage natural behaviors. The water temperature must be kept stable between 23°C and 26°C (73-79°F). Heating can be managed with a standard heater, ensuring there are no sudden temperature changes.

Water Quality: The water must be very soft and acidic, simulating a blackwater habitat: pH between 5.5 and 6.5, general hardness (GH) below 6 dGH, and carbonate hardness (KH) close to zero. The use of reconstituted reverse osmosis water and the addition of peat extracts or leaves to release beneficial humic acids and tannins is highly recommended.

Compatibility and Cohabitation: A benthic omnivore. The diet must be varied and of high quality, including specific sinking bottom-dweller tablets, frozen bloodworms, brine shrimp, tubifex, and live foods. Given their nature, it is important to ensure that food actually reaches the bottom of the tank and is not entirely consumed by fish swimming in the mid-water.

Aquarium Breeding: An extremely peaceful species. It coexists perfectly with small characins (tetras), pencilfish (Nannostomus), dwarf cichlids of the genus Apistogramma, and other peaceful Corydoras. Avoid housing them with large, territorial, or aggressive fish that could intimidate them or treat them as prey, which would jeopardize their health.

Risks and Diseases: Barbels are prone to bacterial infections if the substrate is dirty or sharp; regular cleaning of the sand by siphoning is essential. They are highly sensitive to heavy metals, copper, and sudden increases in ammonia and nitrite levels, which can be fatal. Maintain efficient filtration but keep the water flow moderate.