Notopteroidei is a suborder of the order Osteoglossiformes that contains the extant families Gymnarchidae (aba), Notopteridae (feather backs and knifefish) and Mormyridae (elephantfishes), as well as several extinct taxa.
Notopteroidei is a suborder within the order Osteoglossiformes, which includes various fish species like feather backs, knifefish, and elephantfishes.