Pollen morphology of Beauprea (Proteaceae): Modern and fossil

Abstract

Pollen from seven species of Beauprea (Proteaceae), endemic to New Caledonia, fall into two distinct morphological groups based on the presence or absence of sculptural elements. The “unsculptured” types comprise B. filipes, B. gracilis and B. spathulaefolia, and those which are either verrucate or gemmate include B. asplenioides, B. balansae, B. comptonii and B. montana. They all display the typical Beauprea features: tricolpoid apertures, thicker exine in the mesocolpial regions, and gradual tapering of the exine, especially the nexinal layer, towards the aperture. Beauprea is recorded in Late Cretaceous and Cenozoic sediments from Australia and New Zealand, as Beaupreaidites elegansiformis Cookson and Beaupreaidites verrucosus Cookson. Its extinction in the early Miocene in Australia may have been caused by the onset of dry conditions, while a climatic cooling in the Pliocene may have led to an early Pleistocene extinction in New Zealand.