Protacanthopterygii

Brown trout ( Salmo trutta fario )

The Protacanthopterygii are one of the four sub- cohorts of Euteleosteomorpha within the genuine bony fish ( Teleostei ). The name means "before the Stachelflossern ( Acanthopterygii ) ". Protacanthopterygii live both in the sea and in fresh water, mostly in the northern hemisphere.

Features

A definition of Protacanthopterygii is difficult because they show a mosaic of primitive, modern and again reduced features. They are therefore not very broadly defined, namely by Johnson & Patterson (1996 ) by only two skeletal synapomorphies:

Next they all have in common the absence of spines in the fins, cycloid scales and an open connection between the mouth and swim bladder ( Physostomen ).

System

The Protacanthopterygii to Nelson ( 2006) are four orders, twelve families, 94 genera and about 350 species:

  • Gold Lachsartige ( Argentiniformes )
  • Lachsartige ( Salmoniformes )
  • Stint behaved ( Osmeriformes )
  • Pike -like ( Esociformes )

The assignment of the pike -like is controversial. Often they are today, not considered Protacanthopterygii, but as a sister group of all higher Teleostei, the Neoteleostei. They do not share with them a tooth attachment, in which only the rear side of the tooth is attached by connective tissue to the tooth base, the front, making the big teeth, can fold down like the pike, prey Passage.

The recently made ​​classification of Maulstachler as a sister group of the smelt -like made ​​the Protacanthopterygii in the previous sense paraphyletic. For this reason, access Betancur -R. et al. (2013 ) to the decision ( with the exception of galaxies) from the Protacanthopterygii outsource the smelt -like and combine with the mouth Stach learning in the new sub- cohort Stomiatii (except for the salamander fish, which stands alone in the new sub- cohort Lepidogalaxii now). The galaxies form according to this current system, the order of its own Galaxiiformes within the Protacanthopterygii, see the following cladogram:

Lepidogalaxii ( salamander fish)

Gold Lachsartige ( Argentiniformes )

Galaxies ( Galaxiiformes )

Pike -like ( Esociformes )

Lachsartige ( Salmoniformes )

Stint behaved ( Osmeriformes )

Maulstachler ( Stomiiformes )

Neoteleostei

Taxonomic rank#All ranks Joseph S. Nelson
662564
de