Cytoevolution, phylogeny and taxonomy in epacridaceae

Abstract

Chromosome numbers in Epacridaceae were collated from various authors and superimposed on to recent cladograms for the family. The results strongly indicate that reduction in chromosome number occurs with evolutionary advancement. Thus Epacridaceae, in common with 'Ericaceae sens. strict.' and 'Vacciniaceae sens, strict., has evolved from a primitive karyotype of at least x = 12 and probably x= 13. This conclusion dispels earlier paleopolyploid models based on a primitive x= 6 in the family. Other aspects of cytoevolution, such as chromosome number as a generic character especially in cytologically advanced genera of the Styphelieae, are discussed.