Numerical and cytotaxonomic evidence for generic delimitation in Australian Euphorbieae

Abstract

Chromosome numbers are reported for 24 Australian taxa of the tribe Euphorbieae Dumort. (Euphorbiaceae), with base numbers of x = 6, 7, 8, 9 and 11. The distribution of the base numbers into cytologically homogeneous groups conforms with the morphological groups as derived from a computer analysis. On the basis of these observations, Chamaesyce S. F. Gray is accepted as a genus distinct from Euphorbia L., and appropriate new combinations are made for the taxa used in this study.