Circumscription of Ericaceae (Ericales) as determined by preliminary cladistic analyses based on morphological,anatomical, and embryological features

Cladistic analyses of selected taxa of Ericaceae (and potential relatives) suggest that the family, as traditionally circumscribed, is paraphyletic. The traditionally recognized groups, Monotropaceae, Pyrolaceae, Epacridaceae, and Empetraceae, are nested within the cladistic structure of Ericaceae, and it seems reasonable to expand the circumscription of the latter. Preliminary analyses suggest thatActinidia (Actinidiaceae) likely is cladistically basal within Ericales, withCyrilla (Cyrillaceae) andClethra (Clethraceae) positioned, respectively, as second and first outgroups to Ericaceae. Generic relationships within Ericaceae are highly unresolved due to extensive homoplasy, butEnkianthus appears to be the sister group of the remaining ericad genera. The current division of the family into five subfamilies, i.e., Rhododendroideae, Ericoideae, Vaccinioideae, Pyroloideae, and Monotropoideae, very likely is not in accordance with phylogenetic relationships.