Open Paleo

Megalosauria

Bonaparte, 1850

Its genera lived 170.9–93.9 million years ago Middle Jurassic–Late Cretaceous

Megalosauria is a clade of tetanuran theropod dinosaurs, the node uniting Spinosauridae and Megalosauridae to which Carrano and colleagues (2012) applied the existing name. It sits within the broader superfamily Megalosauroidea and unites two major lineages: the megalosaurids, large-bodied terrestrial predators such as Megalosaurus and Torvosaurus, and the specialized spinosaurids such as Spinosaurus. The more basal piatnitzkysaurids fall outside the clade, while Streptospondylus, known mainly from fragmentary remains, is difficult to place with confidence and is treated as a wildcard taxon near its base. Its members lived from the Middle Jurassic through the Late Cretaceous.

Diagnosis

  1. External naris positioned behind the premaxillary tooth row
  2. Lateral lamina of the maxilla forming a large shelf that obscures the anteroventral corner of the antorbital fossa
  3. Broad midline depression on the basioccipital about two-thirds the width of the occipital condyle
  4. Enlarged, subcircular third dentary alveolus
  5. Iliac pubic peduncle with a length-to-width ratio of about 1.55 to 1.75
  6. Stout, bar-like medial distal crest on the femur

Clades within Megalosauria

Genera placed directly in Megalosauria

  • Streptospondylus Meyer, 1832 Callovian–Oxfordian (165.3–154.8 Ma)Franceincertae sedisunder dispute

References

  1. Bonaparte, C. L. (1850). Conspectus Systematum Herpetologiae et Amphibiologiae. Editio Altera Reformata. E. J. Brill.

    Printed Megalosauria as an alternative name for his order Dinosaurii, comprising Iguanodontidae, Megalosauridae and Geosauridae; Carrano and colleagues (2012) credit the name to it.

    bonaparte1850a
  2. Carrano, M. T.; Benson, R. B. J.; Sampson, S. D. (2012). The phylogeny of Tetanurae (Dinosauria: Theropoda). Journal of Systematic Palaeontology 10(2): 211-300. Informa UK Limited. doi:10.1080/14772019.2011.630927

    Applied Megalosauria to the node uniting Spinosauridae and Megalosauridae, with Streptospondylus as Megalosauria incertae sedis.

    carrano2012a