&i;Lopholejeunea&o; with ca. 30 species is the largest genus of &i;Lejeuneaceae&o; subfam. &i;Ptychanthoideae&o;. The genus is well characterized by the usually blackish pigmented plants, unlobed underleaves, stems with enlarged cortical cells, isodiametrical leaf cells with homogeneous oil bodies, absence of gynoecial innovations, 2-5-keeled perianths with toothed to laciniate keels, a non-articulate seta, and only 30 elaters per capsule. Three subgenera are provisionally recognized: the pantropical subg. Lopholejeunea (ca. 25 species), subg. Pteryganthus with four species in East Africa, and the monospecific subg. Pholianthus (L. colensoi) in Australia and New Zealand. The Malesian archipelago is the center of diversity for Lopholejeunea. In Asia subg. Lopholejeunea includes 17 species assigned to two sections: sect. Lopholejeunea (nine species) characterized by having the leaf lobule apex attached to the lobe across 2-8 cells, and sect. Eulophae (eight species) characterized by having the lobule apex attached to the lobe by only one cell. Subgenus Laciniatae is newly treated as a synonym of Lopholejeunea subg. Lopholejeunea. Seven sections are reduced to synonymy (sections Latilobulae, Longicaules, Parvae, and Subfuscae = sect. Lopholejeunea; sections Acutifoliae, Constrictae, and Muellerianae = sect. Eulophae). Two new species, Lopholejeunea grollei from New Guinea and L. soae from China, are described. A synopsis of subgenera and sections is provided, and a key to sections and species in Asia is given. Each species is described and fully illustrated, and detailed habitat and distribution data are provided.