ABSTRACT: 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.