A new Oligocene-Miocene calcareous nannofossil species: Pontosphaera wallacei
Keywords: سنگ آهک نانوفسیل; Oligocene; Miocene; Taxonomy; Calcareous nannofossils; Atlantic OceanOligocène; Miocène; Taxonomie; Nannofossiles calcaires; Océan Atlantique