Fungal genera: Jaculispora [2 taxa], Jaffuela [1 taxon], Jafneadelphus [1 taxon], Jahnoporus [2 taxa], Jahnula [2 taxa], Jamesdicksonia [2 taxa], Janetia [2 taxa], Japewia [5 taxa], Jattaea [8 taxa], Jobellisia [11 taxa], Johansonia [9 taxa], Johansoniella [1 taxon], Johnwebsteria [1 taxon], Jola [12 taxa], Julella [15 taxa], Junctospora [2 taxa], Junghuhnia [134 taxa]