Discosia (teleomorph unknown) and Seimatosporium (teleomorph Discostroma) are saprobic or plant pathogenic, coelomycetous genera of so-called 'pestalotioid fungi' within the Amphisphaeriaceae (Xylariales). They share several morphological features and their generic circumscriptions appear unclear. We investigated the phylogenies of both genera on the basis of SSU, LSU and ITS nrDNA and β-tubulin gene sequences. Discosia was not monophyletic and was separated into two distinct lineages. Discosia eucalypti deviated from Discosia clade and was transferred to a new genus, Immersidiscosia, characterised by deeply immersed, pycnidioid conidiomata that are intraepidermal to subepidermal in origin, with a conidiomatal beak having periphyses. Subdividing Discosia into 'sections' was not considered phylogenetically significant at least for the three sections investigated (sect. Discosia, Laurina, and Strobilina). We recognised Seimatosporium s.l. as a monophyletic genus. An undescribed species belonging to Discosia with its associated teleomorph was collected on living leaves of Symplocos prunifolia from Yakushima Island, Japan. We have therefore established a new teleomorphic genus, Adisciso, for this new species, A. yakushimense. Discostroma tricellulare (anamorph: Seimatosporium azaleae), previously described from Rhododendron species, was transferred to Adisciso based on morphological and phylogenetic grounds. Adisciso is characterised by relatively small-sized ascomata without stromatic tissue, obclavate to broadly cylindrical asci with biseriate ascospores that have 2 transverse septa, and its Discosia anamorph. Based on these features, it can easily be distinguished from Discostroma, a similar genus within the Amphisphaeriaceae.

The family Lophiotremataceae (Pleosporales, Dothideomycetes) is taxonomically revised on the basis of morphological observations and phylogenetic analyses of sequences of nuclear rDNA SSU, ITS, and LSU regions and tef1 and rpb2 genes. A total of 208 sequences were generated from species of Lophiotremataceae and its relatives. According to phylogenetic analyses, Lophiotremataceae encompasses the genus Lophiotrema and five new genera: Atrocalyx, Crassimassarina, Cryptoclypeus, Galeaticarpa, and Pseudocryptoclypeus. These genera are characterised by ascomata with or without a slit-like ostiole and pycnidial conidiomata. Three new families, Aquasubmersaceae, Cryptocoryneaceae, and Hermatomycetaceae, are proposed. Two genera previously recognised as members of Lophiotremataceae, namely, Aquasubmersa having ascomata with a papillate ostiolar neck and pycnidial conidiomata and Hermatomyces possessing sporodochial conidiomata and dimorphic (lenticular and cylindrical) conidia, are included in Aquasubmersaceae and Hermatomycetaceae, respectively. Cryptocoryneum, characterised by the presence of stromatic sporodochia, cheiroid conidia, and conidial arms developed downward from the cap cells, is placed in Cryptocoryneaceae. Two new genera, Antealophiotrema and Pseudolophiotrema, are established, but their familial placements remain unresolved. Antealophiotrema bears ascomata morphologically similar to those of Lophiotrema, but is differentiated from the latter by having ascomata with a well-developed peridium and a monodictys-like asexual morph. Pseudolophiotrema is also similar to Lophiotrema, but can be distinguished by ascomata with a thin peridium. A total of three new families, seven new genera, eight new species, and two new combinations are described and illustrated.