Definition of pelycosaur in English:

pelycosaur

noun

  • A large fossil reptile of the late Carboniferous and Permian periods, typically having a line of long bony spines along the back supporting a sail-like crest.

    Order Pelycosauria, subclass Synapsida: several families and genera, including Dimetrodon and Edaphosaurus

    • ‘The transition between pelycosaurs and therapsids has not been documented.’
    • ‘It is a box-like construction, more like a pelycosaur than a mammal, with the large flat maxillae forming the sides, the nasal the top, the the tall premaxilla at the rostral end.’
    • ‘This gap is all the more extreme because pelycosaurs and therapsids are each large, internally-diverse groups.’
    • ‘A characteristic pelycosaur was Dimetrodon, a large predator from the Permian of Texas.’
    • ‘An interesting example of convergent evolution is seen between these pelycosaurs and the unrelated dinosaurs.’
    • ‘Whereas the Early Permian pelycosaur record is extensive, Carboniferous pelycosaur remains are rare and poorly known.’
    • ‘It may be intermediate in structure between the pelycosaurs and the therapsids.’
    • ‘All groups of pelycosaurs went extinct by the end of the Permian.’
    • ‘Between the Carboniferous pelycosaurs and the first Jurassic mammals, the jaw articulation changed.’
    • ‘Nevertheless these primitive animals were more advanced on the road the to mammalian evolution, and, like the pelycosaurs, diverged along several lines as herbivores, carnivores, or omnivores.’

Origin

Late 19th century: from Greek pelux, peluk- ‘bowl’ + sauros ‘lizard’.

Pronunciation

pelycosaur

/ˈpɛlɪkəsɔː/