Molecular phylogeny of Coelogyne (Epidendroideae; Orchidaceae) based on plastid RFLPS, matK, and nuclear ribosomal its sequences: Evidence for polyphyly

To evaluate the monophyly of Coelogyne (Epidendroideae: Orchidaceae) and re veal sectional relationships and relations to allied genera in subtribe Coc logyninae, we collected PCR (polymerase chain reaction) amplified restricti on fragment length polymorphisms (RFLPs) from 11 plastid regions for 42 tax a (28 Coelogyne species and 14 representatives of other genera) and three o utgroups from Bletiinae and Thuniinae. We also sequenced a large portion of the plastid trnK intron (mostly matK) and the nuclear ribosomal DNA intern al transcribed spacers ITS1 and ITS2 (including the 5.8S gene). Separate ph ylogenetic analyses on each data set using maximum parsimony produced mainl y congruent (except for the position of Panisea) but weakly supported clade s. Parsimony analysis of the combined data clearly identified three main cl ades in Coclogyninae. Whereas Coelogyninae are monophyletic, Coelogyne is p olyphyletic, with species failing into at least two well-supported clades. The utility of morphological characters used in previous classifications wa s explored by reconstructing character state evolution on one of the four m olecular trees. Lip base and petal shape were homoplasious. whereas ovary i ndumentum and flower number were congruent with well-supported groups. The implications of our results for the classification of Coelogyne are discuss ed. and a reorganization of the genus by including Neogyna and Pholidota an d removing several species is proposed.