Facts about Mammal-like Reptiles, an extinct prehistoric animal

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Dinosaur Jungle   >   Other Prehistoric Animals   >   Mammal-like Reptiles


Mammal-like Reptiles

Scientific Classification
  Kingdom Animalia
  Phylum Chordata
  Class Synapsida
Amniotes (tetrapod vertebrate animals with a terrestrially adapted eggs) are traditionally divided into three categories:
  • Anapsids - Animals with a box-like skull without openings. This group includes the early reptiles of the Carboniferous and Permian periods (and to a limited extent the Triassic period), and includes animals such Scutosaurus. This group may also include turtles, however many scientists believe that turtles are actually descended from Diapsid reptiles which lost their skull openings.

  • Diapsids - Reptiles with two temporal holes (fenestra) in their skulls, and their descendents. This group includes archosaurs (including crocodilians, dinosaur species and birds), as well as lepidosaurs such as lizards, snakes, and sphenodonts - even though many of these groups have lost one hole (lizards), both holes (snakes), or have heavily modified skulls (birds).

  • Synapsids (also sometimes known as "Theropsids") - Animals with a single temporal opening (fenestra) in theirn skull behind each eye. This group includes many reptiles, known as "mammal-like reptiles", as well as mammals. Some examples of mammal-like reptiles include Cynodonts, Dicynodonts, Gorgonopsians (including Lystrosaurs), Dinocephalians like Estemmenosuchus, Moschops and Struthiocephalus, as well as Pelycosaurs like Dimetrodon, Edaphosaurus, Sphenacodon, and Varanosaurus.

Mammal-like Reptiles Timeline:

Mammal-like Reptiles were one of the main groups of amniotes, including the ancestors of all modern mammals, and lived between 324 and 100 million years ago

Mammal-like Reptiles were one of the main groups of amniotes, including the ancestors of all modern mammals, and lived between 324 and 100 million years ago

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