The phylogenetic and palaeogeographic evolution of the miogypsinid larger benthic foraminifera

Abstract

Access to new material from South Africa, Corsica, Cyprus, Syria and Sumatra has allowed a systematic biostratigraphic comparison and correlation of the miogypsinids from the Mediterranean–West Africa and the Indo-Pacific provinces, and for the first time from South Africa. Twelve new species have been identified: Neorotalia tethyana, Miogypsinella bornea, Miogypsina subiensis, M. niasiensis, M. regularia, M. samuelia, Miolepidocyclina banneri, Miogypsinella cyprea, Miogypsina mcmillania, M. africana, M. ianmacmilliana and M. southernia . The palaeogeographical evolution of the miogypsinids started with a trans-Atlantic migration of Neorotalia from the Americas, where miogypsinids had originated. The eastward migration followed two paths: one to the south towards South Africa, where a distinct phylogenetic lineage, but similar to that found in America, developed but went extinct in the Burdigalian; the other to the north, through the Mediterranean corridor. During the Chattian and Aquitanian significant miogypsinid forms evolved in the Mediterranean from the morphologically distinct Mediterranean Neorotalia and migrated, within a few million years of their first appearance, into the Indo-Pacific, where they diversified further. The tectonically driven closure of the seaway between the Mediterranean and the Indo-Pacific in the Burdigalian triggered the extinction of Mediterranean miogypsinids in the Langhian. Miogypsinids survived in the Indo-Pacific into the Serravallian.