XVI International Botanical Congess

Simple organography makes fossil taxodiaceous conifer remains difficult to identify. Up to 21 fossil Metasequoia species have been proposed, but there may be as few as two. Several thousand Metasequoia-like specimens from Paleocene deposits of Alberta, Canada, include shoots, ovulate cones, seeds, pollen cones, pollen and seedlings. These reveal a novel combination of characters that fall outside the ranges of variation for well-known species. This whole-plant concept approaches a taxonomic species of living plants, and allows for accurate recognition of diversity among extinct taxodiaceous conifers.