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 unofficial group also includes C. burgessi, C. davidsandsi, C. duplicareus, C. imitator, C. melini, and C. serratus, and among these C. duplicareus is most easily-confused with C. adolfoi.

The type series was said to have been collected from a “whitewater area”, but images of the rio Unini depict a blackwater system typical of the rio Negro basin, and this is supported by empirical evidence. There are sections of rapidly-flowing water so perhaps this is what the author was referring to.

Habitats should therefore comprise tributaries and areas of flooded forest where the water is…

This species can be told apart from congeners by its uniformly greyish colour pattern, deep body (fitting 2.1-2.4 times in standard length), large eye (3.2-4.0 times in head length), having the pectoral fins completely surrounded by the coracoid, and relatively long dorsal-fin spine (1.1-1.2 times in head length).

Scleromystax spp. are foraging omnivores, and most will accept 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.

This species’ name is commonly misapplied to a number of similar-looking fishes and it can be difficult to identify if collection locality is unknown. In addition, colour pattern is variable and it’s not clear whether this occurs between, within, or both between and within populations.

In the original description, Steindachner did note that the first three dorsal-fin rays are completely black while the remainder is whi…

The most obvious distinguishing characters are that the black marking in the upper part of the body is restricted to the area beneath the dorsal-fin and extends into the majority of the fin , while the paler patch anterior to it, on top of the head, is yellowish rather than orangish.

Additional diagnostic characters have proven unavailable thus far since it was described in a hobbyist magazi…

This species is somewhat variable in appearance and can have between 1-3 dark lateral stripes on each flank, for example. It’s also known by the alternative common name ‘pink corydoras’.

It looks similar to the congener C. loxozonus plus unidentified fishes which have been assigned the codes C003 and CW021, and all four are sometimes traded under the fabricated names C. ‘deckeri’ or C. sp. ‘decker/deker’.

Type locality is given as ‘Small tributary of the upper Rio Negro on the equator near São Gabriel da Cachoeira, Brazil’, and this species is apparently highly endemic there.

Some sources state that it also occurs in the rio Uaupés (known as ‘Vaupés’ in Colombia), a major tributary of the Negro, but we’ve been unable to obtain confirmation thus far.

This species is among the more popular Corydoras in the aquarium hobby and is widely available. It may also be referred to as ‘arched cory’.

There exist a number of similar-looking congeners, particularly C. urucu (Britto et al., 2009), described from the rio Urucu in Coari municipality, Amazonas state, Brazil, and C. narcissus from the rio Purus. The latter appears to have also been traded as C. sp. ‘super arcuatus longnose’ while a larg…

Despite the ubiquity of its name in aquarium literature, confusion surrounds its true identity. Given it’s the only member of the genus occurring on the island, fish from Trinidad do presumably represent C. aeneus (see our image), but the classification of those from other localities appears far from certain.

Today the species is accepted to occur throughout much of South America, and indeed similarly-patterned fish do occur across a large portion of the continent. Some of these, such as the gree…