Lepidosauromorpha

From Palaeos

o Eureptilia
`--o DIAPSIDA
   |--Araeoscelidia (paraphyletic?)
   `--+?--Avicephala
      `--o Neodiapsida
         |?-Coelurosauravidae
         `--+--Apsisaurus
            `--+?-Claudiosaurus
               `--o==Younginiformes (paraphyletic?)
                  `--+?-Ichthyopterygia
                     `--o Sauria
                        |--Lepidosauromorpha
                        `--Archosauromorpha

[edit] Introduction

Lepidosauromorpha are a group of reptiles comprising all diapsida closer to lizards than to archosaurs (including crocodiles and bird). Formerly this was a deverse group that included both an assemblage of basal proto-lizard-like forms (including the Kuehneosaurs or Triassic gliding "lizards") and the Sauropterygia (plesiosaurs and their relatives). The most successful and diverse sub-clade is however the Lepidosauria, which include extant lizards, snakes and various extinct forms (including the Cretaceous Mosasaurs), as well as the tuatara and its Mesozoic ancestors and relatives.

Rieppel and deBraga have argued that turtles are actually the sister group to Sauropterygia (which would make them also Lepidosauromorphs), but this remains a controversial hypothesis.

o Sauria
|?-Thalattosauriformes
`--o LEPIDOSAUROMORPHA
   |--Acerosodontosaurus [Acerosodontosauridae]
   |--+--Sauropterygia
   |  `?-Testudinata (Rieppel & deBraga)
   `--Lepidosauriformes

[edit] Information

Range: from the Late Permian.

Phylogeny: Sauria: Archosauromorpha + Lepidosauromorpha : Sauropterygia + Lepidosauriformes.

Author Benton, 1983

[edit] Characters

Characters: retroarticular process large; teeth absent on lateral pterygoid flanges; parasphenoid teeth absent; postfrontal borders upper fenestra; supratemporal absent; quadrate wide in posterior view, forming conch; quadrate bowed in lateral view; quadrate foramen absent; intercentra absent from trunk vertebrae; no bipedal specializations; rigid pectoral girdle; large sternum; overlapping scales.

[edit] Taxonomy

this section from Wikipedia:

• Subclass Diapsida
  • LEPIDOSAUROMORPHA
    • Acerosodontosaurus (extinct)
    • Superorder Sauropterygia - Plesiosaurs (extinct)
    • Lepidosauriformes
      • Order Eolacertilia (paraphyletic?)
        • Icarosaurus
        • Kuehneosaurus
      • Superorder Lepidosauria
        • Order Sphenodontia - Tuatara
        • Order Squamata
          • Suborder Lacertilia (Paraphyletic) - Lizards
            • Family Mosasauridae
          • Suborder Serpentes - Snakes
          • Suborder Amphisbaenia - Worm lizards

[edit] Links

<a href="http://www.geocities.com/CapeCanaveral/Hall/1636/sauropsida/lepidosauromorpha.html">Lepidosauromorpha -- (lizards > birds)</a>; <a href="http://www.unl.edu/ecology/ballinger/jon/herps/clas.html">Reptilian Systematics</a>; <a href="http://www.karger.ch/journals/BBE/BBE504/BBE0198.htm">S. Karger AG, Basel - Brain, Behavior and Evolution Abstract 198, Vol. 50, No. 4, 1997</a>; <a href="http://palaeo.gly.bris.ac.uk/cladestore/reptilia.html">Reptilia.html</a>; <a href="http://dinosauricon.com/taxa/lepidosauromorpha.html">Lepidosauromorpha -- The Dinosauricon</a>; <a href="http://www.ohiou.edu/phylocode/art13.html">PhyloCode Article 13</a>; <a href="http://evolution.anat.ucl.ac.uk/people/northwood/Diapsida.htm#Lepidosauromorpha">Diapsida.htm</a>; <a href="http://www.butantan.gov.br/museu/br/serp_origem.pdf">serp_origem.pdf</a> (Portuguese, <a href="http://www.butantan.gov.br/museu/ing/serp_origem.pdf">English</a>); <a href="http://www.cmnh.org/dinoarch/1999Feb/msg00579.html">Acrocoracoids & reptile phylogeny</a>; <a href="http://tolweb.org/tree/eukaryotes/animals/chordata/lepidosauromorpha.html">Lepidosauromorpha</a> (ToL: still nothing here); <a href="http://www.fosil.cl/lepidosauromorpha.html">Untitled</a> (Spanish: short, but useful discussion of anatomical changes in locomotion).   ATW030715.

[edit] Credits

ATW030715 Palaeos com, this page MAK070107