Irish checklist:

A Preliminary Check-list of the Algae of Ireland has been produced by Michael D. Guiry (September, 2019).

The preliminary check-list of current names for freshwater, marine and terrestrial (including aerophytic) algae of Ireland is extracted from the distributional data in AlgaeBase ( as of September 2019, and each name and its source is traceable on-line there. Some 2,879 current species names are presently included. Nine phyla/divisions are included, eight of them from the Eukaryota and one (Cyanobacteria) from the Prokaryota.

National checklists are available for desmids (John, Williamson & Guiry,2011) and seaweeds (Guiry 2012), and for diatoms by Carter in Wolnik & Carer (2014).


Guiry, M.D. (2019) A Preliminary Check-list of the Algae of Ireland. Ryan Istitute NUI, Galway. (Download checklist)

Guiry, M.D. (2012) A catalogue of Irish seasweeds. pp.[1]-250, 1 pl. Ruggel:A.R.G. Gantner Verlag K.G.

John, D.M., Williamson, D.M. & Guiry, M.D., 2011. A catalogue of the desmids (Streptophycophyta, Zygnematophyceae, Zygnematales) of Ireland. Occasional Papers . National Botanical Gardens Glasnevin Dubin 15:1-83.

Wolnik, L. & Carter, R.T. (2014) Diatoms Ireland

Number of algal species:

2,879 known species (but exact number is likely to exceed 5,000 species, or about 10% of the world’s species of algae)

Table of checklists for Algal species




Primary sources of distribution data:

*Databases held by the National Biodiversity Data Centre and made accessible through Biodiversity Maps.

National conservation assessment:

  • Stewart, N.F. & Church, J.M.1992. Red Data Books of Britain and Ireland: Stoneworts. The Joint Nature Conservation Committee, Peterborough, UK.

Monitoring or repeat surveys in place:

Water Framework Monitoring Programme (EPA). Estuarine & coastal survey work includes algae.