Stenopterygii

thumb|left|Stomiidae ([[Stomiiformes), from top to bottom:Northern Stoplight Loosejaw (Malacosteus niger),Eustomias braueri,Bathophilus vaillanti,Leptostomias gladiator,Rhadinesthes decimus,Photostomias guernei and its mouth]]

Stenopterygii are a superorder of ray-finned fish in the infraclass Teleostei. Their validity is somewhat doubtful, as the group was established to separate, out of a large group of closely related Teleostei, a mere two rather peculiarly autapomorphic orders at best. In some treatments, it is even monotypic.