Dothideales

Abstract: A survey of the endophytic fungi in fronds of Livistona chinensis was carried out in Hong Kong. The endophyte assemblages identified using morphological characters consisted of 16 named species and 19 'morphospecies', the latter grouped based on cultural morphology and growth rates. Arrangement of taxa into morphospecies does not reflect species phylogeny, and therefore selected morphospecies were further identified based on ribosomal DNA (rDNA) sequence analysis. The 5.8S gene and flanking internal transcribed spacers (ITS1 and ITS2) regions of rDNA from 19 representative morphospecies were amplified by the polymerase chain reaction and sequenced. Phylogenetic analysis based on 5.8S gene sequences showed that these morphospecies were filamentous Ascomycota, belonging in the Loculoascomycetes and Pyrenomycetes. Further identification was conducted by means of sequence comparison and phylogenetic analysis of both the ITS and 5.8S regions. Results showed that MS704 belonged to the genus Diaporthe and its anamorph Phomopsis of the Valsaceae. MS594 was inferred to be Mycosphaerella and its anamorph Cladosporium of the Mycosphaerellaceae. MS339, MS366, MS370, MS395, MS1033, MS1083 and MS1092 were placed in the genus Xylaria of the Xylariaceae. MS194, MS375 and MS1028 were close to the Clypeosphaeriaceae. MS191 and MS316 were closely related to the Pleosporaceae within the Dothideales. The other 5 morphospecies, MS786, MS1043, MS1065, MS1076 and MS1095, probably belong in the Xylariales. The value of using DNA sequence analysis in the identification of endophytes is discussed.

Abstract: The class Dothideomycetes is the largest and most ecologically diverse class of fungi, comprising endophytes, epiphytes, saprobes, human and plant pathogens, lichens, and lichenicolous, nematode trapping and rock-inhabiting taxa. Members of this class are mainly characterized by bitunicate asci with fissitunicate dehiscence, and occur on broad range of hosts in aquatic and terrestrial habitats. Since the last monograph of families of Dothideomycetes in 2013, numerous novel species, genera, families and orders have been discovered. This has expanded information which has led to the modern classification in Dothideomycetes. In this paper, we provide a refined updated document on families of Dothideomycetes with emphasis on Dothideomycetidae and Pleosporomycetidae. We accept three orders with 25 families and four orders with 94 families in Dothideomycetidae and Pleosporomycetidae, respectively. The new family Paralophiostomataceae is introduced in Pleosporales. Each family is provided with an updated description, notes, including figures to represent the morphology, list of accepted genera, and economic and ecological significances. We also provide an overall phylogenetic tree of families in Dothideomycetes based on combined analysis of LSU, SSU, rpb-2 and tef1 sequence data, and phylogenetic trees for each order in Dothideomycetidae and Pleosporomycetidae. Familylevel trees are provided for the families which include several genera such as Mycosphaerellaceae and Teratosphaeriaceae. Two new genera (Ligninsphaeriopsis and Paralophiostoma) are introduced. Five new species (Biatrisopora borsei, Comoclathris galatellae, Ligninsphaeriopsis thailandica, Paralophiostoma hysterioides and Torula thailandica) are introduced based on morphology and phylogeny, together with nine new reports and seven new collections from