The Notacanthiformes are an order of deep-sea ray-finned fishes, consisting of the families Halosauridae and Notacanthidae (spiny eels). The order is of relatively recent vintage; Fishes of the World (2006) lists it as the suborder Notacanthoidei of Albuliformes. The notacanthiforms are much more eel-like than the albuliforms; for instance, the caudal fin has disappeared.
Species taxanomy provided by GBIF Secretariat (2022). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org on 2023-06-13; License: CC BY 4.0