Multivariate analysis of morphological variation in Cineraria deltoidea (Asteraceae, Senecioneae)

Abstract

Cluster analysis and principal coordinates analysis were used to investigate phenetic variation in Cineraria deltoidea, a species that ranges from near sea level in KwaZulu-Natal, South Africa, to 4300 m a.s.l. on the mountains of East Africa and Ethiopia. Earlier taxonomic revisions reduced nine previously recognized species to synonyms of C. deltoidea. Two closely related species, C. decipiens and C. atriplicifolia, were also included in the analyses. Thirty-six morphological characters were examined on 111 specimens. Phenograms and scattergrams show partial clusters of specimens of C. deltoidea from individual mountains or geographical regions, but no groups are sufficiently distinct to warrant formal recognition at any rank. The East African specimens from 3000 m a.s.l. and higher tend to cluster together. Growth at high altitude in East Africa is correlated with fewer, larger capitula on longer peduncles, and an absence of a cobwebby indumentum comprising long, narrow-based trichomes. Cineraria deltoidea is thus a highly variable species with geographical and clinal variation evident throughout its range. Cineraria atriplicifolia and C. decipiens are maintained as distinct species, distinguished from C. deltoidea by their growth form, life span and auricle shape.