Hornwort (Anthocerotopsida) spores in Late Quaternary wetland sediments and dryland soils, Rapa Nui (Easter Island)

Abstract

Several paleoecological studies over the last decade examining plant microfossils in Late Quaternary wetland sediment cores and dryland soil samples from multiple sites on Rapa Nui found three distinct spore forms, comparable to the class Anthocerotopsida. To our knowledge, hornwort spores have not been noted specifically as such in previous or to date subsequent, published paleoecological Rapa Nui studies. As the spore descriptions in the studies were brief, without images, and reported in several separate articles, here we provide detailed descriptions and photomicrography of the spores, and comment on their distribution and dating in the sampled substrates and suggest botanical affinities.

We identify two native Rapa Nui hornwort taxa, with possibly localised distributions, and another, possibly introduced taxon with widespread Rapa Nui distribution. All three taxa are associated with major landscape disturbance by people. As we cannot find any other descriptive studies of hornwort spores from east of and including French Polynesia, this study provides a platform for subsequent similar research in the region.

Keywords

Microfossils, bryophites, Anthocerotophyta, Anthocerotae, Anthocerotaceae, Notothyladaceae, Pacific Islands.