ON THE TAXONOMIC IDENTITY OF THE PLANKTONIC FORAMINIFERAL SPECIES GLOBOROTALIA BARISANENSIS LE ROY, 1939

摘要

Examination of the holotype of Globorotalia barisanensis Le Roy, 1939, has revealed that this species from the Middle Miocene of central Sumatra is non-keeled, contradicting the synonymizing of G. barisanensis with Globorotalia fohsi. Because the type sample is untraceable, we examined the available type specimens (holotype and eight paratypes), notes and data presented by previous researchers, and material from the near-topotype locality of Paragloborotalia siakensis, to clarify Le Roy's concept of G. barisanensis. Our investigation has revealed that the Middle Miocene of central Sumatra contains two different groups of globorotaliids: the Globorotalia menardii group and the G. fohsi group, and that G. barisanensis belongs to the latter.