BIOSTRATIGRAPHY AND PROTEROGENESIS OF VERNEUILINA FAUNA FROM THE SOUTHERN TETHYS

Abstract

The Campanian-Ypresian (C-Y) fauna in the Southern Tethys (ST) include rich small benthic foraminifera (SBF) reveals significant biostratigraphic changes during the C-Y transition. A progressive evolutionary trend within the Verneuilina lineage allowed to establish the Campanian V. iraqensis Total Range Zone (TRZ), and three successive zones in the Maastrichtian-Ypresian, namely: the Maastrichtian V. aegyptiaca Interval Range Zone (IRZ), the Paleocene V. laevigata IRZ, and the Ypresian V. luxorensis TRZ, which may correlate with the standard planktonic foraminifera zones: Globotruncana aegyptiaca IRZ to Acarinina pentacamerata PRZ, and span about 23 M.Y. (75-52 Ma). On the other hand, a minor difference in the test morphology and differences in the stratigraphic ranges of the members of the genus Verneuilina are recognized as being of decisive specific value. For that, the Proterogenesis Rule can be applied here on the Late C-Y six species of the genus Verneuilina, and these are: Verneuilina aegyptiaca and V. karreri, V. laevigata and V. luxorensis. Another two species are believed here as new: Verneuilina iraqensis and Verneuilina jordanica. The identified species were recorded from many localities in the ST (Tunisia, Egypt, Jordan, Iraq, Iran, United Arab Emirates, Qatar and Pakistan), and one of them are recorded in Spain, in the Northern Tethys (NT).