Wikipedia
AlgaeBase is a Global Species Database of information on all groups of algae, as well as one group of flowering plants, the sea-grasses.
AlgaeBase evolved from Michael Guiry's seaweed website, and has grown into a database of algae from throughout the world, and in freshwater, terrestrial, and brackish as well as marine habitats. By 2005, the database contained about 65,000 names, and by September 2006, 122,240 species and infraspecific names were in the database, with 5,826 images, 38,290 bibliographic items, 138,706 distributional records. Currently, the data for the marine algae, particularly seaweeds, are the most complete. About 30,000 species of algae are included, of which the Rhodophyta (6000 species), marine Chlorophyta (1500 species), and Phaeophyceae (1755 species) are the most complete. The diatoms and the smaller freshwater green algae are currently (August 2010) the most incomplete groups.
Programming is carried out by VisualID (http://www.visualid.com) (Pier Kuipers and Caoilte Guiry) and the compilation of the data was funded by the Irish Government Department of Education and Science's PRTLI 3 and 4 programmes (http://www.hea.ie/en/prtli).