Ichthyostega

Ichthyostega
Temporal range: Late Devonian (Famennian), 365–360 Ma
Reconstructed skeleton in Moscow Paleontological Museum
Skeletal reconstruction
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Sarcopterygii
Clade: Tetrapodomorpha
Clade: Stegocephali
Family: Ichthyostegidae
Säve-Söderbergh, 1932
Genus: Ichthyostega
Säve-Söderbergh, 1932
Type species
Ichthyostega stensioei
Säve-Söderbergh, 1932
Other species[1][2]
  • I. eigili
    Säve-Söderbergh, 1932
  • I. kochi?
    Säve-Söderbergh, 1932
  • I. watsoni
    Säve-Söderbergh, 1932
Synonyms
Genus synonymy
  • Ichthyostegopsis
    Säve-Söderbergh, 1932
Species synonymy
  • Ichthyostega stensiöi
    Säve-Söderbergh, 1932
  • Ichthyostegopsis wimani
    Säve-Söderbergh, 1932

Ichthyostega (from Greek: ἰχθῦς ikhthûs, 'fish' and Greek: στέγη stégē, 'roof') is an extinct genus of limbed tetrapodomorphs from the Late Devonian of what is now Greenland. It was among the earliest four-limbed vertebrates ever in the fossil record and was one of the first with weight-bearing adaptations for terrestrial locomotion. Ichthyostega possessed lungs and limbs that helped it navigate through shallow water in swamps. Although Ichthyostega is often labelled a 'tetrapod' because of its limbs and fingers, it evolved long before true crown group tetrapods and could more accurately be referred to as a stegocephalian or stem tetrapod. Likewise, while undoubtedly of amphibian build and habit, it is not a true member of the group in the narrow sense, as the first modern amphibians (members of the group Lissamphibia) appeared in the Triassic Period. Until finds of other early stegocephalians and closely related fishes in the late 20th century, Ichthyostega stood alone as a transitional fossil between fish and tetrapods, combining fish and tetrapod features. Newer research has shown that it had an unusual anatomy, functioning more akin to a seal than a salamander, as previously assumed.[3]

  1. ^ Haaramo, Mikko. "Taxonomic history of the genus †Ichthyostega Säve-Söderbergh, 1932". Mikko's Phylogeny Archive. Blom, 2005. Retrieved 24 October 2015.
  2. ^ "Ichthyostega". Paleofile. Retrieved 24 October 2015.
  3. ^ Cite error: The named reference pierce2012 was invoked but never defined (see the help page).