Dendrobium Sw. is one of the three largest orchid genera, with around 1580
species if certain currently accepted satellite genera are included. Until recently, no serious
attempts have been made to split up this important genus into smaller genera. An infrageneric
classification at the sectional level, largely due to Schlechter, has been accepted by most
workers. Recent analyses based on DNA markers by Yukawa, Clements, and others have
provided new insights into the phylogeny of Dendrobium. Their work shows that Dendrobium
is not monophyletic when the satellite genera are excluded. This led to proposals to split up
Dendrobium into as many as fifty genera, largely along the lines of Schlechter’s sections.
However, the data do not suggest any single, evident way to do the splitting. Here it is argued
that a broad concept of the genus Dendrobium, which includes genera like Cadetia Gaudich.,
Flickingeria A.D.Hawkes and Epigeneium Gagnep., among others, is to be preferred. The
comparable cases of other large orchid genera are briefly discussed and some observations are
made on character evolution in Dendrobium and the origin of the genus in light of DNA-based
phylogenies.