Michael Dominic Richard Guiry (born 1949), is an Irish botanist,[1] who specialises in phycology (algae).

[2][3][4][5] He is the founder and director of the algal database, AlgaeBase.

In addition to his interest in the taxonomy and the databasing of algae, his algal site promotes the sustainable use of seaweed resources.

[6] Since 2009, he has been an emeritus professor at the Ryan Institute, National University of Ireland, in Galway.

[8] (in AlgaeBase, as Guiry, over 300 algal species listed, not all currently accepted) (incomplete)