Akmonistion

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Akmonistion
Temporal range: Serpukhovian
Akmonistion zangerli Coates & Sequeira.jpg
Holotype fossil
Akmonistion zangerli.png
Reconstruction
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Order: Symmoriiformes
Family: Stethacanthidae
Genus: Akmonistion
Species:
A. zangerli
Binomial name
Akmonistion zangerli
Coates & Sequeira, 2001

Akmonistion is an extinct genus of cartilaginous fish that lived in the Early Carboniferous. The genus contains a single species, A. zangerli, discovered by Stan Wood in 1982. [1] It is distinguished by an unusual enlarged formation of the dorsal fin, called a "spine-brush complex", of unknown function. This is also found in the better known genus Stethacanthus . Remains have only been found near Bearsden in Scotland. [2] [3] The genus name is derived from the Ancient Greek “akmon” (“anvil”) + “istion” (“sail”) referring to the appearance of its first dorsal fin. [2] It reached 62 cm (24 in) in length. [2]

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References

  1. Wood, S.P. (1982). "New basal Namurian (Upper Carboniferous) fishes and crustaceans found near Glasgow". Nature. 297: 574–577.
  2. 1 2 3 Coates, M.I.; Sequeira, S.E.K. (2001). "A new stethacanthid chondrichthyan from the lower Carboniferous of Bearsden, Scotland" (PDF). Journal of Vertebrate Paleontology. 21 (3): 438–459. doi:10.1671/0272-4634(2001)021[0438:anscft]2.0.co;2.
  3. "Akmonistion zangerli". Palaeobiology Database.