Palaeotethys There is confusion over the relationship between Tethys (or Neotethys) and Palaeotethys. Some authors refer to the existence of a late Palaeozoic Palaeotethys which was a gulf at the margin of Panthalassa between the parts of Pangaea that were later to separate as Laurasia and Gondwanaland. This ocean, or large parts of it, were consumed in a Palaeocimmerian-Indosinian subduction zone. In the Jurassic a new ocean, or oceans, opened along the northern margin of Palaeotethys. This Jurassic-Cretaceous ocean has been called Neotethys or Tethys (sensu stricto).

Palaeotethys In the view of some authors, a late Palaeozoic gulf at the margin of Panthalassa, between the parts of Pangaea that were later to separate as Laurasia and Gondwana. This ocean, or large parts of it, were consumed in a Palaeocimmerian–Indosinian subduction zone. In the Jurassic a new ocean, or oceans, opened along the northern margin of Palaeotethys. This Jurassic–Cretaceous ocean has been called Neotethys or Tethys (sensu stricto).