Taxonomy
The name Corydoras is derived from the Greek kory (helmet) and doras (skin). Corydoras is by far the largest genus of Neotropical fishes with more than 142 species. In addition, many variants exist. It is the sole genus in the tribe Corydoradini. C. difluviatilis is recognized as the basalmost species of Corydoradini, exhibiting several plesiomorphic features compared to the other species of Corydoras. The type species for this genus is Corydoras geoffroy. Several hundred Corydoras species are not yet classified, but kept by aquarists. These species are given C-Numbers, originally devised by Hans-Georg Evers for the German fishkeeping magazine DATZ in 1993. In 2006, there were 153 C-numbers assigned, of which 32 had been assigned appropriate scientific names.
The C. barbatus, C. macropterus, and C. prionotos have been reclassified into the genus Scleromystax. Brochis had been differentiated from Corydoras due to the higher number of dorsal fin rays; however, Brochis has recently been suggested to be a synonym of Corydoras. This is contested and has not been universally accepted. The sixray corydoras belongs in Aspidoras.
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