Abstract
New localities for Chionoloma orthodontum (Pottiaceae) are reported from Japan. The species is characterized by its narrow leaf base with a V-shaped cell pattern, the excurrent costa forming a short mucro and the presence of rhizoidal tubers. Based on Japanese material, a full description, analytical illustrations, and ecological information are provided. The phylogenetic position of the Japanese plants is inferred on the basis of chloroplast atpB–rbcL, trnG and trnL–F sequences.
