Original: A few species are familiar to the aquarium trade, such as the black ghost knifefish (Apteronotus albifrons), the glass knifefish (Eigenmannia virescens), and the banded knifefish (Gymnotus carapo).
Simplified: Other species familiar in the aquarium trade are: the black ghost knifefish (Apteronotus albifrons), the glass knifefish (Eigenmannia virescens), and the banded knifefish Gymnotus carapo.