This species is traded under various other names including ‘red arc pencilfish’, ‘Peruvian red pencilfish’, ‘ruby red pencilfish’, ‘red pencilfish’, and Nannostomus cf. marginatus ‘red’.

It was initially described as a subspecies of N. marginatus but can be identified by the following combination of characters: pronounced sexual dimorphism with adult males exhibiting bright red pigmentation between the central…

This species was previously thought to be, and is often still sold as, A. hancockii, a name currently considered synonymous with Platydoras hancockii (Valenciennes 1840). It’s also known by the vernacular names of blue-eyed catfish or Hancock’s doradid, and in many ways is an ideal beginners’ catfish, being hardy and tolerant of a wide range of water conditions…

Numerous ornamental forms of this species have been selectively-bred for the aquarium trade, some of which include. It has also been assigned the 'A' number A234 under the DATZ system with possibly conspecific, related forms similarly numbered A235, A236, A237, A238, A239, A240, A241 and A242 depending on locality.

The genus Apistogramma is among the most speciose of South American cichlid genera with around 70 species valid at present but many more awaiting description. In addition …