Upatoia barnardii gen. et sp. nov., an araucarian pollen cone with in situ pollen from the Late Cretaceous (Santonian) of Georgia, USA

Upatoia barnardii gen. et sp. nov., a conifer pollen cone from the Late Cretaceous (Santonian) Eutaw Formation of Upatoi Creek, Georgia, USA, is known from lignified and fusainised mesofossils that preserve its three-dimensional structure. The cone consists of numerous helically arranged microsporophylls, each composed of a thin stalk and distal lamina. Three elongate pollen sacs are attached to the base of the lamina. Pollen grains isolated from the pollen sacs are relatively large (52 - 75 μm), spheroidal to ellipsoidal in outline, lack sacci, and have a thickened equatorial exine that is often strongly folded. Pollen of Upatoia barnardii indicates a close relationship to extant Araucariaceae. Microsporophylls of U. barnardii confirm suggestions from previous studies of fossil material that some Mesozoic Araucariaceae had only three pollen sacs per microsporophyll, in contrast to extant species that often have more than ten pollen sacs per microsporophyll.