Gogonasus

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Gogonasus
Drawing reconstruction of Gogonasus

Drawing reconstruction of Gogonasus

Temporal occurrence
Upper Devonian
approx. 380 million years
Locations
Systematics
Trunk : Chordates (chordata)
Sub-stem : Vertebrates (vertebrata)
Superclass : Jaw mouths (Gnathostomata)
Class : Meat finisher (Sarcopterygii)
Tetrapodomorpha
Genre : Gogonasus
Scientific name
Gogonasus
Long , 1985
Art
  • Gogonasus andrewsae Long , 1985

Gogonasus is the name of an approximately 380 million year old genus of fossil fish from the late Upper Devonian . Due to their anatomical features and the geological layers in which the fossils were found, Gogonasus is considered an early relative of Panderichthys and Tiktaalik and thus - like them - as the forerunner of the later land vertebrates (tetrapods). A forerunner of Gogonasus was again a fossil fish called Eusthenopteron .

The genus Gogonasus had been known from Western Australia since 1985 . However, the gill regions and the fins, among other things, were poorly preserved in all the finds . It was not until an unusually well-preserved specimen discovered in 2005 in a limestone quarry in the same region (NMV P221897, Museum Victoria, Melbourne ), which even internal organs could be detected with the aid of X-ray analyzes, revealed surprising details: “A mosaic of plesiomorphic and derived Tetrapod-like characteristics. ”In addition to many characteristics typical of fish, Gogonasus - similar to Panderichthys - already had greatly enlarged injection holes (breathing holes) in the area of ​​the gills, from which the auditory canal and middle ear later developed. The arrangement of the pectoral fin bones is similar to that of Tiktaalik , the prehistoric fish that is closest to land vertebrates as far as we know today.

See also

Web links

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

Individual evidence

  1. ^ " Gogonasus shows a mosaic of plesiomorphic and derived tetrapod-like features ", quoted from the description of the find: John A. Long, Gavin C. Young, Tim Holland, Tim J. Senden, Erich MG Fitzgerald: An exceptional Devonian fish from Australia sheds light on tetrapod origins. Nature . Volume 444, No. 7116, November 9, 2006, pp. 199-202. doi : 10.1038 / nature05243