|Named By:||L. Makadi, M. W. Caldwell & A. Osi in 2012|
|Time Period:||Late Cretaceous, 85.3-83.5 Ma|
|Location:||Hungary - Csehbanya Formation|
|Size:||Roughly about 6 meters long|
|Fossil(s):||Almost complete skull and post cranial skeleton|
|Classification:||| Chordata | Reptilia | Squamata | Mosasauridae | Russellosaurinae | Tethysaurinae ||
Pannoniasaurus is an extinct genus of tethysaurine mosasauroid known from the Late Cretaceous Csehbanya Formation (Santonian stage) of Hungary. It contains a single species, Pannoniasaurus inexpectatus, dubbed "unexpected" because it was discovered in freshwater sediments, unlike other mosasaurs, which were marine predators. It was a medium sized mosasaur, reaching up to 6 m (20 ft).