ascomycetes completing their whole life history in living leaves. The Rhytismatales is a large and diverse order, and most of its species are endophytes. Here we included three endophytic taxa to display the significant morphological change between the leaf endophytes and saprobic species in Cudoniaceae in this order. Members of the Erysiphales are leaf living fungi and share a similar ecology with leaf endophytes. Most Erysiphales fungi produce the somatic mycelia exclusively on leaf surfaces, with a kind of hyphal structure (a haustoria) penetrating the leaf surface and tissues for nutrition. 2. Whether or not a species features highly reduced ascomata morphology compared with their sister groups. Significant reductions of the ascomata have occurred multiple times across ascomycetes. Ascomycetes only known by their asexual stage or yeasts, which are not leaf-endophytes, were considered as highly reduced taxa in our analyses. 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