Ichthyopterygia

Source: Wikipedia, the free encyclopedia.

Ichthyopterygians
Temporal range:
Ma
Utatsusaurus
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: †Ichthyosauriformes
Superorder: †Ichthyopterygia
Owen, 1840
Subgroups

See text.

Ichthyopterygia ("fish flippers") was a designation introduced by

ichthyosaurs that were known at the time, but the term is now used more often for both true Ichthyosauria and their more primitive early and middle Triassic ancestors.[1][2]

Basal ichthyopterygians (prior to and ancestral to true Ichthyosauria) were mostly small (a meter or less in length) with elongated bodies and long, spool-shaped vertebrae, indicating that they swam in a sinuous, eel-like manner. This allowed for quick movements and maneuverability that were advantages in shallow-water hunting.[3] Even at this early stage, they were already very specialised animals with proper flippers, and would have been incapable of movement on land.

These animals seem to have been widely distributed around the coast of the northern half of

stem group
members were extinct, having been replaced by their descendants, the true ichthyosaurs.

Fossil remains of derived marine ichthyopterygians, and the oldest ichthyopterygian remains to date, are known from the Olenekian aged

Late Smithian crisis (a widespread ocean anoxic event that may have allowed ichthyopterygians to dominate deeper waters and temnospondyls to dominate shallow waters) and that ichthyosauromorphs as a whole originated during the Permian and were survivors of the Permian-Triassic mass extinction.[4][5]

Taxonomy

Nasorostrans and basal ichthyopterygians
  • Superorder Ichthyopterygia
    • ? Genus Isfjordosaurus
    • Family
      Parvinatatoridae
    • Family
      Thaisauridae
    • Family
      Utatsusauridae
    • Eoichthyosauria
      • Order
        Grippidia
      • Order
        Ichthyosauria

Phylogeny

Below is a cladogram modified from Cuthbertson et al., 2013.[6]

Ichthyopterygia

Parvinatator wapitiensis

Utatsusaurus hataii

Xinminosaurus catactes

Eoichthyosauria
Grippidia

Grippia longirostris

Gulosaurus helmi

Ichthyosauria sensu Motani (1999)

Chaohusaurus geishanensis

Cymbospondylus

Mixosauria

Mixosaurus cornalianus

Phalarodon atavus

Toretocnemidae

Qianichthyosaurus zhoui

Toretocnemus californicus

Shastasauria

Shonisaurus popularis

Shastasaurus pacificus

Callawayia neoscapularis

Guizhouichthyosaurus tangae

Besanosaurus leptorhynchus

Californosaurus perrini

Parvipelvia

References

  1. ^ Motani, R. (1997). "Temporal and spatial distribution of tooth implantation in ichthyosaurs". In J. M. Callaway; E. L. Nicholls (eds.). Ancient Marine Reptiles. Academic Press. pp. 81–103.
  2. S2CID 4416186
    .
  3. PMID 11103459
    .
  4. PMID 24647136
    .
  5. PMID 36917937
    .
  6. S2CID 131501541
    .

General references

External links

Wikispecies has information related to Ichthyopterygia.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Ichthyopterygia&oldid=1186962033"