This fish is one of a number of apparently unidentified Scleromystax species known in the aquarium hobby.

The genus Scleromystax 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.

It is most similar to S. macropterus, but differs in absence (vs. presence) of a black spot on the base of the median caudal-fin rays, a higher number of pectoral-fin rays (I,8,i vs. I,7,i), males with somewhat more slender bodies (25.7- 30.5% in SL [range 26.3-28.8% in type series] vs. 30.4-34.6% in SL), an…

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.

Known from minor rivers in the coastal states of São Paolo, Paraná, and Santa Catarina, southern Brazil, plus some tributaries of the rio Paraná basin in Paraguay.

Type locality is ‘Paranaguá, 25°32’S, 48°36’W, Paraná, Brazil’.

Unfortunately diagnostic characters cannot be provided since we have been unable to obtain the type description to date, and little else has been written about this species.

There is also confusion regarding whether C. lamberti, the unidentified ‘C009’, and similar-looking fish collected close to Iquitos are conspecific or not. We include all together here until these issues are resolved.

Known only from the rio Ivaí basin, a tributary of the rio Paraná in Paraná state, southern Brazil.

Type locality is ‘Brazil, Paraná, Cândido de Abreu, rio Maria Flora, tributary to rio Ubazinho, rio Ivaí basin…

Prior to description C. kanei was assigned the ‘C’ numbers C026 and C046.

Among congeners it is most easily-confused with, and sometimes traded as, C. atropersonatus, but can be identified by presence (vs. absence in C. atropersonatus) of dark markings in the anal and caudal fins, presence of numerous, smaller (vs. fewer, larger) dark spots on the body, and an overall darker (vs. paler) base colouration.

It also exhibits morphological adaptations to an existence among rocks in a flowing environment, such as a cryptic colour pattern, reduced spine length in the dorsal and pectoral fins, ventrally-oriented pectoral fins, slightly emarginate caudal-fin, and reduced body depth.

Reduced fin spines and body depth are typical features associated with the related genus Aspidoras, but the…

The Río Calchaquí rises at almost 6000 m AMSL and flows swiftly through a mountainous valley where it is largely fed by snow melt. The climate is semi-arid and cool with an air temperature of 12-18°C, while rainfall is largely concentrated during summer when the flow can be torrential. The water is hard and rich in salts, with pH measured at 8.04 during the month of August. Aquatic vegetation and filamentous algae grow around the margins and in tributaries.

It can be distinguished from the majority of other Corydoras species by its distinctive colour pattern, comprising a uniform, lightish base pigmentation with a dark arched stripe extending over the upper portion of each flank, from the tip of the snout to the caudal-fin base. This is shared with a few congeners, however, including C. arcuatus, C. narcissus, and C. urucu.