Ornatorotalia pila n. sp. from the late Palaeocene of Iran: ecological, evolutionary and paleobiogeographic inferences

The upper Palaeocene shallow-water carbonates of the Qorban member (Sachun Formation) in Iran are characterised by a well-diversified larger Foraminifera and green algae assemblages. A new ornatorotaliid species, Ornatorotalia pila n. sp., is described from such deposits. The age of the new taxon is assigned to SBZ4 (late Thanetian) by the co-occurrence of Daviesina langhami, Idalina sinjarica, Lockartia retiata and Dictyokathina simplex. This new record gives further evidences on the biogeographic expansion of throughout the Neo-Tethys during the Palaeocene-early Eocene. Ornatorotaliids were shallow-water dwellers taxa that thrived in both vegetated and unvegetated bottoms. Possibly, Ornatorotalia pila n. sp. rooted in the Selandian, likely related to a possible ancestor described in open nomenclature from the Central Apennines of Italy.