Fungal genera: Uberispora [3 taxa], Uleiella [4 taxa], Uleodothis [6 taxa], Uleomyces [10 taxa], Uleopeltis [1 taxon], Uleothyrium [1 taxon], Ulocladium [97 taxa], Ulocolla [1 taxon], Umbellidion [15 taxa], Umbellula [3 taxa], Umbelopsis [8 taxa], Umbilicaria [2 taxa], Uncinia [2 taxa], Uncinula [703 taxa], Uncinuliella [102 taxa], Underwoodia [10 taxa], Unguicularia [17 taxa], Unguiculariopsis [16 taxa], Unguiculella [38 taxa], Ungulina [9 taxa], Uraecium [3 taxa], Urceolella [10 taxa], Uredinella [2 taxa], Uredinophila [21 taxa], Uredinopsis [32 taxa], Uredo [1602 taxa], Uredopeltis [1 taxon], Urnula [15 taxa], Urocystis [197 taxa], Urohendersonia [8 taxa], Uromyces [7369 taxa], Uromycladium [1 taxon], Urophlyctis [2 taxa], Uropyxis [40 taxa], Urospora [1 taxon], Urosporella [1 taxon], Urosporellopsis [1 taxon], Usnea [621 taxa], Ustalia [1 taxon], Ustilaginoidea [77 taxa], Ustilago [1817 taxa], Ustulina [153 taxa], Utharomyces [4 taxa], Uthatobasidium [1 taxon], Uvarispora [1 taxon]