Upper Eocene planktonic foraminifera from northern Saudi Arabia: implications for stratigraphic ranges

Abstract. The Rashrashiyah Formation of the Sirhan Basin in northern Saudi Arabia contains diverse assemblages planktonic foraminifera. We examined biostratigraphy, stratigraphic range and preservation upper Eocene Assemblages are well-preserved diverse, with 40 species 11 genera. All samples assigned to Priabonian Globigerinatheka semiinvoluta Highest Occurrence Zone (E14), consistent calcareous nannofossil biostratigraphy indicating CNE17. Well-preserved foraminifera from lower part rare worldwide. Our study provides new insights into ranges many species. find older (Zone E14) occurrences several Globoturborotalita previously thought have evolved latest E15, E16) or Oligocene; these include G. barbula, cancellata, gnaucki, pseudopraebulloides, paracancellata. Older for Dentoglobigerina taci Subbotina projecta also found, kugleri occurs at a younger level than proposed. revisions indicate that late had higher tropical–subtropical diversity hitherto reported.