2006 年 100 巻 p. 41-52
Based on a comparison of type and other specimens, Ptychomitrium patens (Müll. Hal.) Par. and P. obtusifolium (Borth.) Par. are reduced to synonymy of P. sellowianum (Müll. Hal.) Jaeger, and P. papillosum (Herz.) Card. is reduced to synonymy of P. chimborazense (Mitt.) Jaeger. Three new combinations are proposed: P. gardneri var. angustifolium (Nog.) Cao & Guo, P. sellowianum var. angustifolium (Broth.) Cao & Guo, and P. hieronymi var. obtusifolium (Thér.) Cao & Guo. Ptychomitrium ferrugineum (Herz.) Broth. is described in detail based on the holotype.