Stenopterygii are a superorder of ray-finned fish in the infraclassTeleostei. 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 autapomorphicorders at best. In some treatments, it is even monotypic.[1]
As originally conceived, the "Stenopterygii" include the Ateleopodiformes and Stomiiformes. Sometimes, the former are removed to form a monotypic superorder Ateleopodomorpha. These lineages are moderately advanced teleosts, but each is uniquely adapted to a deep-water oceanic environment. Their plesiomorphies are similar to the Salmoniformes and other Protacanthopterygii, but plesiomorphic traits are no reliable indicator of a close relationship. Nonwithstanding, the "Stenopterygii" appear to be close relatives of the Protacanthopterygii. Some cladistic analyses find at least the Stomiiformes deep within the latter superorder.[2]
It thus cannot be ruled out that the "Stenopterygii" are better included in the Protacanthopterygii. An alternative approach is to consider the entire group – "Stenopterygii", Protacanthopterygii, the monotypic superorders "Cyclosquamata", and perhaps the monotypic superorders "Lampridiomorpha" and "Scopelomorpha" – an unranked clade named Euteleostei. But this would probably require splitting up the Protacanthopterygii, so that each euteleost superorder would at most contain 2 orders (though most would be monotypic), as the relative placement of all these groups is not very well resolved. Such a profusion of monotypic taxa is generally rejected by modern taxonomy, if it is not absolutely required to adequately reflect phylogeny.[3]
Moreover, owing to the uncertain relationships of the euteleosts to the less advanced Otocephala (which include the superorders Clupeomorpha and Ostariophysi) and the more advanced teleosts (e.g. Acanthopterygii), it may well be that the supposed "clade" is merely an evolutionary grade. Such a paraphyletic group would according to modern understanding not warrant a taxon name at all. In this case, a possible solution would be to expand the Protacanthopterygii to subsume all the small "superorders", and to treat the Euteleostei as including the Protacanthopterygii and their more "modern" relatives.[3]
Media related to Stenopterygii at Wikimedia Commons
Diogo, Rui (2008): On the cephalic and pectoral girdle muscles of the deep sea fish Alepocephalus rostratus, with comments on the functional morphology and phylogenetic relationships of the Alepocephaloidei (Teleostei). Anim. Biol.58(1): 23-29. doi:10.1163/157075608X303636
stenopterygii, superorder, finned, fish, infraclass, teleostei, their, validity, somewhat, doubtful, group, established, separate, large, group, closely, related, teleostei, mere, rather, peculiarly, autapomorphic, orders, best, some, treatments, even, monotyp. 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 1 StenopterygiiArgyropelecus aculeatus Sternoptychinae Scientific classificationKingdom AnimaliaPhylum ChordataClass ActinopterygiiSubclass NeopterygiiInfraclass TeleosteiSuperorder Stenopterygii disputed OrdersAteleopodiformes but see text StomiiformesSynonymsAtelopodomorpha but see text Stomiidae Stomiiformes from top to bottom Northern Stoplight Loosejaw Malacosteus niger Eustomias braueri Bathophilus vaillanti Leptostomias gladiator Rhadinesthes decimus Photostomias guernei and its mouthAs originally conceived the Stenopterygii include the Ateleopodiformes and Stomiiformes Sometimes the former are removed to form a monotypic superorder Ateleopodomorpha These lineages are moderately advanced teleosts but each is uniquely adapted to a deep water oceanic environment Their plesiomorphies are similar to the Salmoniformes and other Protacanthopterygii but plesiomorphic traits are no reliable indicator of a close relationship Nonwithstanding the Stenopterygii appear to be close relatives of the Protacanthopterygii Some cladistic analyses find at least the Stomiiformes deep within the latter superorder 2 It thus cannot be ruled out that the Stenopterygii are better included in the Protacanthopterygii An alternative approach is to consider the entire group Stenopterygii Protacanthopterygii the monotypic superorders Cyclosquamata and perhaps the monotypic superorders Lampridiomorpha and Scopelomorpha an unranked clade named Euteleostei But this would probably require splitting up the Protacanthopterygii so that each euteleost superorder would at most contain 2 orders though most would be monotypic as the relative placement of all these groups is not very well resolved Such a profusion of monotypic taxa is generally rejected by modern taxonomy if it is not absolutely required to adequately reflect phylogeny 3 Moreover owing to the uncertain relationships of the euteleosts to the less advanced Otocephala which include the superorders Clupeomorpha and Ostariophysi and the more advanced teleosts e g Acanthopterygii it may well be that the supposed clade is merely an evolutionary grade Such a paraphyletic group would according to modern understanding not warrant a taxon name at all In this case a possible solution would be to expand the Protacanthopterygii to subsume all the small superorders and to treat the Euteleostei as including the Protacanthopterygii and their more modern relatives 3 Footnotes edit Nelson 2006 pp 207 208 212 213 Nelson 2006 pp 207 208 212 213 Diogo 2008 a b Diogo 2008 References edit nbsp Media related to Stenopterygii at Wikimedia Commons Diogo Rui 2008 On the cephalic and pectoral girdle muscles of the deep sea fish Alepocephalus rostratus with comments on the functional morphology and phylogenetic relationships of the Alepocephaloidei Teleostei Anim Biol 58 1 23 29 doi 10 1163 157075608X303636 Nelson Joseph S 2006 Fishes of the World 4th ed John Wiley amp Sons Inc ISBN 0 471 25031 7 Retrieved from https en wikipedia org w index php title Stenopterygii amp oldid 1034085882, wikipedia, wiki, book, books, library,
