Revision of Coelogyne section Moniliformes (Orchidaceae) based on morphology, plastid and nrDNA ITS sequences

Section Moniliformes Carr of the orchid genus Coelogyne is revised using morphological and molecular data. Twelve species are recognised, including two new ones (C. chanii and C. renae). and a dubious one (C. crassiloba). A combined analysis of morphological characters, and sequences of the nrDNA ITS region, matK gene, trnT-trnL intergenic spacer, trnL intron and trnL-trnF intergenic spacer supports the monophyly of the section as here recognised. Persistence of the rhizome scales, shape of the margin of the leaves, inflorescence type, shape of the rachis, its nodes and pedicel scars, indument of the floral bracts, lip size and depth of the sinus of the lateral lobes of the hypochile seem to be phylogenetically informative characters. Shape of the leaf blade, flowering mode, shape of the base and keels of the hypochile, shape of the apex of the lateral lobes and keels of the epichile and shape of the column show many parallelisms.