This is an alphabetical list of fungal taxa as recorded from South Africa. Currently accepted names have been appended.
Genus: Icmadophila Trevis. 1852 (lichen)
Genus: Ileodictyon Tul. & C. Tul. 1844
Genus: Imbricaria (Schreb.) Michx. 1803 accepted as Anaptychia Körb., (1848)
Genus: Inocybe (Fr.) Fr. 1863
Genus: Irene Theiss., Syd. & P. Syd. 1917, accepted as Asteridiella McAlpine, (1897)
Genus: Irenina F. Stevens 1927 accepted as Appendiculella Höhn., (1919)
Genus: Irenopsis F. Stevens 1927
Genus: Irpex Fr. 1825
Genus: Isaria Pers. 1794
Genus: Isariopsis Fresen. 1863 accepted as Ramularia Unger, Exanth. (1833)
Genus: Isidium Ach. 1794 accepted as Pertusaria DC., in Lamarck & de Candolle, (1805)
Genus: Isipinga Doidge 1921 accepted as Asterina Lév., (1845)
Genus: Isothea Fr. 1849
Genus: Itajahya Möller 1895
Genus: Ithyphallus Gray 1821 accepted as Mutinus Fr., (1849)