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

ABSTRACT

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.

KEYWORDS:

• Foraminifera
• systematics
• ornatorotaliid
• Palaeocene
• shallow-water carbonates

Acknowledgments

Thanks to the WO.L.F. friends for their encouragement to promote investigations on new undescribed larger Foraminifera. Prof. J. Pignatti (Rome) kindly facilitated the recovery of crucial bibliographic references. We are grateful to the editor-in-chief G. Dyke for the careful editorial support and to the journal reviewer E. Sirel (Ankara) for the constructive comments.

Disclosure statement

No potential conflict of interest was reported by the authors.