This project was the main focus of about three years (around 1992-1995) of my time while at the Department of Plant Science, University of Tasmania (partially as a post-doc with R.S. Hill) and continued while at the Department of Botany, University of Queensland (partially as a post-doc with M.E. Dettmann) and has continued during my present appointment at the Centre for Marine Studies, University of Queensland. I am most grateful to the Queensland Herbarium and the Australian National Herbarium for access to their collections, and to N. Duke for a specimen of Pelliciera rhizophorae. Many thanks to J.-C. Ortiz for his help with the statistics. The comments of two anonymous reviewers are much appreciated.