Systematics
Together with their relatives, the Stomiiformes, the jellynoses are often placed in the teleost superorder Stenopterygii. Whether it is indeed justified to accept such a small group is doubtful; it may well be that the closest living relatives of the "Stenopterygii" are found among the superorder Protacanthopterygii, and that the former would need to be merged in the latter. In some classifications, the "Stenopterygii" are kept separate but included with the Protacanthopterygii and the monotypic superorder Cyclosquamata in an unranked clade called Euteleostei. That would probably require splitting two additional monotypic superorders out of the Protacanthopterygii, and is probably not ideal due to the profusion of very small taxa it would create. In fact, in some treatments, the jellynose fishes are even placed in yet another monotypic superorder, the Ateleopodomorpha.
The Ateleopodidae have also been placed in the Lampriformes or Myctophiformes, which otherwise constitute additional superorders. The relationships of these to the taxa mentioned before is still not well resolved at all, and regardless whether one calls them Protacanthopterygii sensu lato or Euteleostei, the phylogeny of this group of moderately-advanced Teleostei is in need of further study.
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