In this volume, 128 ascomycetous species are described mainly from plant materials (leaves, stems, branches, roots, fruits, and seeds) as saprophytes or plant pathogens, and occasionally from soil. All of the fungi in this text, are described alphabetically in order of Amphisphaeriales, Botryosphaeriales, Capnodiales, Chaetothyriales, Cladosporiales, Coniochaetales, Diaporthales, Eurotiales, Hypocreales, Kirschsteiniotheliales, Magnaporthales, Orbiliales, Patellariales, Pleosporales, Sordariales, and Xylariales. Each fungus is described with colony characteristics, microscopic features and other useful sequence data available at GenBank (https://www.ncbi.nlm.nih.gov/genbank/). In addition, selected references and literature for taxonomic data and nomenclature, mostly from MycoBank (https://www.mycobank.org), are provided. All photographs and drawings are based on the author’s own work using the materials described. Dried specimens of some fungi are mainly deposited at GUM (University of Guilan, Rasht, Iran), and IRAN…F (Fungus Reference Collection, Herbarium Ministerii Iranici Agriculturae located at Iranian Research Institute of Plant Protection, Tehran, Iran). The living cultures are also preserved at CBS (Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands), and IRAN…C (Iranian Fungal Culture Collection, Iranian Research Institute of Plant Protection, Tehran, Iran).