Two new species of Hornibrookina Edwards, 1973 from the Austral Basin, Patagonia: Biostratigraphical and palaeoecological implications

Abstract

Two new species of the genus Hornibrookina––H. larae sp. nov. and H. nicolasii sp. nov.––are described and illustrated. These species were first reported from surface and subsurface Early to Middle Eocene sedimentary successions in the Austral Basin, Patagonia. Accompanying calcareous nannofossils and foraminifera from an outcrop sample from the Río de la Turba area, where these new species are well preserved and abundant, are discussed to better constrain the age and palaeoecology of the new species. These new species extend the geological range of the genus Hornibrookina into the Late Lutetian–Early Bartonian (NP16) and support its affinity for coastal, eutrophic marine conditions.