The Oligocene of the Western/Central Paratethys was documented by Piller, Harzhauser & Mandic (2007), who listed the regional stages and stated: "During its maximum extent the Paratethys spread from the Rhône Basin in France towards Inner Asia. It was segregated into three paleogeographic and geotectonic units (not only two as sometimes reported, e.g., Nevesskaya 1999; Vasiliev et al. 2004, 2005) each recording a different environmental history.
The smaller western part consists of the Western and the Central Paratethys being opposed by the larger Eastern Paratethys. The Western Paratethys comprises the Alpine Foreland Basins of France, Switzerland, S Germany and Upper Austria (Senes, 1961). The Central Paratethys includes the Eastern Alpine - Carpathian Foreland basins, from Lower Austria to Moldavia, and the Pannonian Basin System. The Eastern Paratethys comprises the Euxinian (Black Sea), Caspian and Aral Sea basins (Nevesskaja et al., 1993).".
A great set of lithological-paleogeographic maps of the Paratethys (Eocene to Miocene) may be found in Popov et al. (2004).
Below a list of regional stages is given, with international stages given between square brackets. Hyperlinks will guide you to search results containing relevant data on Olivoidea.
The regional stages are (oldest first):
Oligocene
Kiscellian [Rupelian-Lower Chattian]. Kiscellian deposits are reported from Austria.
Oligocene-Miocene
Egerian [Chattian -Lower Aquitanian]