The Lake Slavonia,[a] alternatively Paludina Lake,[2] was an ancient fresh-water lake that developed from the middle Pliocene to the early Pleistocene in the southern part of the Pannonian Basin at the time of final retraction of the Pannonian Sea.

[3] The lake was located in the area of modern-day Vojvodina in northern Serbia and eastern Slavonia in Croatia.

In the Pliocene, favourable climatic and geodynamic conditions in southeastern Europe led to the development of extensive, long-lasting lakes like Lake Slavonia.

[4] These lakes saw a rapid diversification of viviparid snails during the warming period reaching its peak between 3.3 and 2.9 million years ago when temperatures rose by as much as 10 °C.

[4][5] M. Neumayr and C. M. Paul, in their 1875 study, used the molluscs from Lake Slavonia to develop a regional biostratigraphy, allowing precise stratigraphic analysis of deposits spanning over 600 km along the southern boundary of the Pannonian Basin.