The stem surface of 9 Chinese species in six sections of the genus Plagiochila is studied by the SEM. Paraphyllia on stem surface in 8 species, and mammillose stem surface in P. caulimammillosa Grolle & M.L.So are described and figured. The paraphyllia of the long known species P. denticulata Mitt. and P. khasiana Mitt. were overlooked hitherto. The paraphyllia differ considerably in number (from one to numerous), distribution (mostly restricted to dorsal side of stem along leaf insertion, but all around the stem in P. pulcherrima Horik.) and shape. Their shape can be spine-like or lamelliform with entire, angulate, dentate or spinose margin.
- stem surface paraphyllia