THE CIRCUMSCRIPTION OF THE ERICALES, AND THEIR CLADISTIC RELATIONSHIPS TO OTHER FAMILIES OF HIGHER DICOTYLEDONS

The relationships of the Ericales have been investigated for a corroborated hypothesis of the circumscription of the order. A Wagner parsimony analysis of 48 families of flowering plants from the Cronquistian subclasses Rosidae, Dilleniidae, and Asteridae, and 49 characters from morphology, anatomy, palynology, embryology, and phytochemistry, resulted in 106 equally parsimonious cladograms (ci = 0.30, ri = 0.67). From the results of the cladistic analysis, it is hypothesized that the Actinidiaceae, Clethraceae, Cyrillaceae, Diapensiaceae, Empetraceae, Epacridaceae, Grubbiaceae, and Roridulaceae, belong in the same clade as Ericaceae, Pyrolaceae, and Monotropaceae, and these families form the newly circumscribed Ericales. A nested set of synapomorphies are involved in diagnosing various nodes of Ericales, such as inverted anthers, presence of ellagic acid, diplostemony, racemose inflorescence, hollow fluted styles, and basally poricidal anthers.