Phenetic analyses of 'Homoranthus' (Myrtaceae: Chamelaucieae) on the basis of morphology

Abstract

'Homoranthus' A.Cunn. ex Schauer is an endemic Australian genus widespread in southern and eastern mainland Australia. Phenetic analyses using clustering and ordination techniques were used to test the limits of all 23 currently recognised species. Data were analysed for 48 morphological characters from 139 specimens representing all species across their geographic ranges. Specimens of 'Homoranthus bornhardtiensis' J.T.Hunter and 'H. prolixus' Craven & S.R.Jones formed one group and appear to be the same entity. A putative natural hybrid between 'H. zeteticorum' Craven & S.R.Jones and 'H. coracinus' A.R.Bean was found to be phenetically intermediate between its putative parent species. Within each of 'H. biflorus' Craven & S.R.Jones s.l., 'H. decumbens' (Byrnes) Craven & S.R.Jones s.l., 'H. melanostictus' Craven & S.R.Jones s.l. and 'H. porteri' (C.T.White) Craven & S.R.Jones s.l., there are two or three distinct entities worthy of recognition as species. There was also strong support for the recognition of an entity from near Tenterfield in northern New South Wales as a distinct species most similar to 'H. montanus' Craven & S.R.Jones. We conclude that a total of 28 species should be recognised within 'Homoranthus', including six new, currently undescribed species.