Pterosaur - Evolution and Extinction - Classification

Classification

For more details on this topic, see List of pterosaur classifications.

Classification of pterosaurs has historically been difficult, because there were many gaps in the fossil record. Many new discoveries are now filling in these gaps and giving a better picture of the evolution of pterosaurs. Traditionally, they are organized into two suborders:

• Rhamphorhynchoidea (Plieninger, 1901): A group of early, basal ("primitive") pterosaurs, many of which had long tails and short metacarpal bones in the wing. They appeared in the Late Triassic period, and lasted until the late Jurassic. Rhamphorhynchoidea is a paraphyletic group (since the pterodactyloids evolved directly from them and not from a common ancestor), so with the increasing use of cladistics it has fallen out of favor in most technical literature.

• Pterodactyloidea (Plieninger, 1901): The more derived ("advanced") pterosaurs, with short tails and long wing metacarpals. They appeared in the middle Jurassic period, and lasted until the Cretaceous–Paleogene extinction event wiped them out at the end of the Cretaceous.

Listing of families and superfamilies within Pterosauria, after Unwin 2006 unless otherwise noted.

• ORDER PTEROSAURIA (extinct)
  • Suborder Rhamphorhynchoidea *
    • Family Anurognathidae
    • Family Campylognathoididae
    • Family Dimorphodontidae
    • Family Rhamphorhynchidae
  • Suborder Pterodactyloidea
    • Superfamily Ornithocheiroidea
      • Family Istiodactylidae
      • Family Nyctosauridae
      • Family Ornithocheiridae
      • Family Pteranodontidae
    • Superfamily Ctenochasmatoidea
      • Family Ctenochasmatidae
      • Family Gallodactylidae
      • Family Pterodactylidae
    • Superfamily Dsungaripteroidea
      • Family Dsungaripteridae
      • Family Germanodactylidae
    • Superfamily Azhdarchoidea
      • Family Azhdarchidae
      • Family Chaoyangopteridae
      • Family Lonchodectidae
      • Family Tapejaridae

The precise relationships between pterosaurs is still unsettled. However, several newer studies are beginning to make things clearer. Cladogram simplified after Unwin.

Pterosauria	Preondactylus Macronychoptera Dimorphodontidae Caelidracones Anurognathidae Lonchognatha Campylognathoididae Breviquartossa Rhamphorhynchidae Pterodactyloidea (see below)

Pterodactyloidea	Ornithocheiroidea Istiodactylidae Euornithocheira Ornithocheiridae Pteranodontidae Lophocratia Ctenochasmatoidea Gallodactylidae Euctenochasmatia Pterodactylus Lonchodectes Ctenochasmatidae Dsungaripteroidea Germanodactylidae Dsungaripteridae Azhdarchoidea Tapejaridae Azhdarchidae