Classification Order: Siluriformes Family: Callichthyidae Distribution Native to tributaries of the rios Negro, Caquetá (both within the Amazon basin), and Orinoco in northwestern Brazil and east-central Colombia. It is known from the rio Uaupés and its tributary the rio Tiquié in the Negro system, the Río Orteguaza in the Caquetá basin, and the Río Losada (upper Río Guaviare) in the Orinoco watershed. Contrary to the majority of aquarium literature, it does not appear to have been collected in the Río Meta watershed, although it does occur in Meta Department, Colombia. Type locality is ‘Jauareté an dem Ausfluss des Rio Papuri in den Rio Uaupés [Brazil]’, which corresponds to Iuaretê (0°35’N, 69°13’W) at the confluence of the rio Papurí and Uaupés. Habitat Inhabits pristine blackwater tributaries and areas of flooded forest where the water is characteristically stained dark with organic chemicals. Such habitats typically contain tea-coloured water with very little detectable hardness, low conductivity, and a pH of 4.0-6.0, with other fishes comprising small characids, lebiasinids, and dwarf cichlids of the genus Apistogramma. Maximum Standard Length 40 – 50 mm. Aquarium Size Base dimensions of 80 ∗ 30 cm or equivalent are recommended for long-term care. It is advised to find a filter which has a water flow between 4-5 times the volume of your aquarium. At a volume of 72 litres, the filter we recommend can be found here. Other aquarium filters which have been recommended highly by customers in your area can be found here. Maintenance Ideally use a substrate of fine sand, although rounded gravel is an acceptable alternative provided it is kept scrupulously clean. Other décor is largely down to personal choice, but some cover should be provided. Driftwood branches and dried leaf litter are useful additions, the latter in particular driving establishment of microbe colonies as decomposition occurs. Such microorganisms can provide a valuable secondary food source for fry, whilst the tannins and other chemicals released by the decaying leaves are also thought beneficial and help simulate natural conditions. Filtration need only be gentle with an air-powered sponge-style unit normally adequate, although a degree of water movement is acceptable. Water Conditions Temperature: 20 – 26 °C pH: 4.0 – 7.0, , though wild fish may do best towards the middle and lower ends of this range. Hardness: 18 – 90 ppm Click here to find the heater we recommend for an aquarium of this size. To search for other high quality aquarium heaters in your area, click here. Diet Corydoras spp. are foraging omnivores and will accept most sinking dried foods, as well as small live and frozen varieties such as chironomid larvae (bloodworm), Tubifex, etc. Feeding a varied diet will ensure the fish are in optimum condition. Under no circumstances should they be expected to survive on ‘left-overs’ from other inhabitants of the aquarium or relied on to ‘clean’ the aquarium. Click on the following links to search for high quality live, frozen and dry food: Bloodworm, Tubifex. To find other high quality, highly recommended foods click here. Behaviour and Compatibility Peaceful and gregarious. Should be maintained in a group of at least 4-6 individuals. Sexual Dimorphism Females tend to grow larger, and sexually mature individuals are noticeably rounder and broader-bodied than males, especially when gravid. Reproduction Can be bred in a similar fashion to many other Corydoras species. Use a ratio of two males per female if possible. When the females are visibly full of eggs perform a large (50-70%) water change with cooler water, and increase oxygenation and flow in the tank. Repeat this daily until the fish spawn. Eggs are normally deposited on the aquarium glass, but it is recommended to provide alternatives in the form of fine-leaved vegetation or fine spawning mops. Once spawning is complete either adults or eggs should be removed; the latter can usually be rolled gently up the glass with a finger. The new container should contain the same water as the spawning tank and be similarly well-oxygenated. Most breeders add a few drops of methylene blue, or an alder cone or two at this point in order to prevent the eggs developing fungus. Incubation is normally 3-4 days and once the fry have fully-absorbed their yolk sacs they are able to accept small live foods such as microworm, Artemia nauplii, etc. They require excellent water quality, but seem less susceptible to ailments when maintained over a thin layer of sand rather than in a bare-bottomed arrangement. Notes This species is among a number of congeners native to the rio Negro region to possess a colour pattern with an oblique dark bar running along the dorsal surface of the body. This group also includes C. adolfoi, C. burgessi, C. davidsandsi, C. duplicareus, C. imitator, C. melini, and C. serratus. In C. melini this bar splits into two above the caudal peduncle, a feature shared only with C. davidsandsi. It can be told apart from C. davidsandsi by lacking (vs. possessing) a pale orange area between the dark head stripe and dorsal bars, and possessing (vs. lacking) additional dark markings on the flanks. In the aquarium hobby, the population from the rio Tiquié has been referred to as ‘C084’, while a similar, slightly larger, form from the Río Huallaga in Peru is known as ‘C085’. Both forms have been marketed as C. sp. ‘mega metae’. The existence of multiple, similarly-coloured species which coexist and sometimes form mixed schools is relatively common in the genus. In some cases Corydoras colour patterns have even evolved in other taxa, such as certain members of the genera Otocinclus, Brachyrhamdia, and Serrapinus. The reason for the success of such patterns is thought to be protection from predators in that they feature cryptic or otherwise disruptive details such as stripes, reticulations, or strongly-coloured fin spines. Similarly-patterned species may therefore have evolved to take advantage of foraging in a larger group while simultaneously adapting to exploit contrasting ecological niches. In Corydoras, this is typically expressed via differences in snout length, mouth position, or body size. The genus Corydoras is among the largest catfish groups and currently contains over 150 valid species. It is included in the family Callichthyidae, of which members are often referred to collectively as ‘armoured’ or ‘mailed’ catfishes group due to the presence of bony plates in place of scales on the body. Their taxonomy can be confusing, and numerous undescribed species are also thought to exist. Fish of unconfirmed identification entering…
