The Turgai Strait, also known as the Turgay/Turgai Sea, Obik Sea, Ural Sea[1] or West Siberian Sea, was a large shallow body of salt water (an epicontinental or epeiric sea) during the Mesozoic through Cenozoic Eras. It extended north of the present-day Caspian Sea to the "paleo-Arctic" region, and was in existence from the Middle Jurassic to Oligocene, approximately 160 to 29 million years ago.[2]
The Turgai Strait was not absolutely continuous throughout this entire era, though it was a persistent and predominating feature in its region; it "fragmented southern Europe and southwestern Asia into many large islands, and separated Europe from Asia."[3]
The division of the Eurasian landmass by the Turgai Sea had the effect of isolating animal populations.[4]
The Turgai Strait derives its name from the Turgay Basin of modern-day Kazakhstan, where a stretch of the Turgai River flows.[5]
Otherwise, most, if not all, continental masses were united into a single land mass — Pangaea. ... (M) Leiopelmatidae (L) Discoglossidae (U) Palaeobatrachidae (U) Cretaceous, 135 m.y. Turgai Sea separated east and west Eurasia