Corydoras duplicareus was first described by Sands in 1995. Corydoras: from the ancient Greek korus, meaning “helmet,” and dora, meaning “skin, skin of an animal,” which refers to the rows of bony plates on the flanks. Duplicareus: from the Latin duplicare ‘double, multiply by two’, refers to the similarity with their cousin Corydoras adolfoi.
Distribution / origin
Brazil, where they were found only in a small part of the upper Negro basin.
Tropical freshwater, both fast-running water with a sandy bottom and also untouched black water rivers and areas of flooded forest where the almost stagnant water is darkly colored by dissolved organic substances.
Corydoras duplicareus has a color pattern with a broad dark (‘black’) bar that runs across the back, and a dark bar, a ‘mask’, also runs over the eye.
They are somewhat similar in appearance to the related Corydoras adolfoi, but this one has a less broad dark band along the back and the orange color spot in the neck is more intense in Corydoras duplicareus. Corydoras duplicareus also has small serrations on the posterior edge of the pectoral fin, which Corydoras adolfoi lack, but this difference is almost invisible to the naked eye.
The maximum total length is approximately 4 to 5 centimeters
Sexing Corydoras duplicareus
It is not easy to determine, but females are generally somewhat larger than the males and sexually mature females are clearly rounder and bulkier than males.
Fine sand is preferably placed on the bottom, while well-rounded gravel is also a good alternative, provided that it is meticulously kept clean. The rounding of the gravel is of great importance in this respect, because these fish can seriously injure themselves on sharp stones when searching for food on and in the substrate.
There must also be sufficient hiding places available for the fish to feel safe. (Bog) wood and dried leaves are appreciated, also because the latter can play a role in the development of useful bacterial colonies. These microorganisms also offer a valuable additional food source for possible offspring, while the tannins and other substances released by slow decomposition of the leaves are also good for simulating natural water conditions.
In the aquarium, the water should have a temperature between 20 – 26 ° C, while the pH must be somewhere between 4.0 – 7.0.
Finally, a varied diet is the best guarantee that the fish will stay in optimum condition.
Corydoras are omnivores and accept both dry food and small live and frozen food (mosquito larvae, tubifex and so on). Although they get food from the soil as small vacuum cleaners, it cannot be assumed that they can only survive on ‘leftovers’ from other inhabitants of the aquarium.
Behaviour and compatibility
These Armored Catfish are peaceful and social, so they should preferably be kept in a school of at least 4-6 copies.
Breeding reports show that successful reproduction has already taken place in the aquarium (in breeding tanks), whereby it is stated that the eggs are deposited on both the sandy bottom and along the water line. See also the breeding report of the Corydoras duplicareus.
Most Corydoras have the option of taking up atmospheric air in addition to gill breathing and extracting oxygen through their intestines. This allows them to survive well in oxygen-poor waters. In the aquarium you can see how they occasionally rise to the surface to take a bite of air.
The hard pectoral fin spines can cause a pretty painful sting if the animals are not carefully handled. It is believed that secretions of glands at those spines as a defense mechanism are mildly toxic.
Menno van Veen
Bijgewerkt op 8 July 2023 door John