Bearded fish

Bearded fish
	Polymixia nobilis , the type species of the genus
Systematics
Sub-cohort :	Neoteleostei
	Acanthomorphata
	Paracanthopterygii
Order :	Bearded fish
Family :	Polymixiidae
Genre :	Bearded fish
Scientific name of the order
	Polymixiiformes
	Rosen & Patterson , 1969
Scientific name of the family
	Polymixiidae
	Gill , 1862
Scientific name of the genus
	Polymixia
	Lowe , 1838

The bearded fish (genus Polymixia ) are a genus of real bony fish (Teleostei) comprising five to nine recent species . The scientific name refers to their skin, which produces "a lot of mucus". The 14 to 48 centimeter long fish live in tropical and subtropical regions of the Atlantic , the Indian Ocean (especially near Natal ) and the western Pacific at depths between 180 and 640 meters.

features

Bearded fish have a moderately elongated, laterally compressed body covered with comb scales . Your eyes are big. Their most striking feature are two head-length hyoid bone barbels , which they use to track down food at the bottom (in sandy to muddy sediment - especially worms, small mussels and crustaceans).

Fin formula : dorsal IV-VI / 26–28, anal IV / 13–17, ventral I / 6, caudal 16.

External system

The systematic position of the bearded fish as a sister group of all other Paracanthopterygii shows the following cladogram:

Eurypterygii

Acanthomorphata

Paracanthopterygii

Bearded fish (Polymixiiformes)

Percopsiformes (Percopsiformes)

	Stylephorus chordatus (Stylephoriformes)

	Cod-like (Gadiformes)

Petersfisch (Zeiformes)

Acanthopterygii

	Perch relatives (Percomorphaceae)

	Soldier fish and hussar fish (Holocentriformes)

Mucous heads (Beryciformes)

Trachichthyiformes

Lampriformes (Lampriformes)

Lanternfish (Myctophiformes)

Lizardfish relatives (Aulopiformes)

Polymixia lowei

Berycopsis

species

After a revision of the genus published in 2019, five of the ten previously described species are still recognized:

Polymixia berndti Gilbert, 1905 .
Polymixia japonica Günther , 1877 .
Polymixia longispina Deng, Xiong & Zhan, 1983 .
Polymixia lowei Günther, 1859 .
Polymixia nobilis Lowe, 1838 .

In addition, four clades were found that are likely to have the status of independent species: Polymixia sp. cf. P. japonica, Polymixia sp. cf. P. lowei, Polymixia sp. cf. P. nobilis and Polymixia sp. nov.

In addition to the only genus still alive today, four other fossil genera are known from the Upper Cretaceous : Berycopsis , Dalmatichthys , Omosoma and Omosomopsis . Polymixia is the last survivor of a larger bony fish radation from the Cretaceous period.

literature

Joseph S. Nelson : Fishes of the World . John Wiley & Sons, 2006, ISBN 0-471-25031-7 .
Kurt Fiedler: Textbook of Special Zoology, Volume II, Part 2: Fish . Gustav Fischer Verlag Jena, 1991, ISBN 3-334-00339-6 .

Individual evidence

^ ^A ^b ^c ^d W. Calvin Borden, Terry C. Grande, Mark VH Wilson: Phylogenetic relationships within the primitive acanthomorph fish genus Polymixia , with changes to species composition and geographic distributions. PLOSone, March, 2019, doi: 10.1371 / journal.pone.0212954

Web links

Commons : Polymixia - collection of images, videos and audio files

Polymixiiformes on Fishbase.org (English)
Polymixiidae on Fishbase.org (English)

[Bordenetal2019-1] A ^b ^c ^d W. Calvin Borden, Terry C. Grande, Mark VH Wilson: Phylogenetic relationships within the primitive acanthomorph fish genus Polymixia , with changes to species composition and geographic distributions. PLOSone, March, 2019, doi: 10.1371 / journal.pone.0212954