A multivariate analysis of morphological variation in the Hemizygia bracteosa complex (Lamiaceae, Ocimeae)

Abstract

The variation and recognition of taxa within the Hemizygia bracteosa complex was examined using multivariate techniques. Morphological characters were sampled on 197 herbarium specimens. Phenetically H. bracteosa and H. welwitschii overlap in many floral characters. However differences in leaf characters and habit maintain their morphological distinctness from each other and they are therefore upheld as species. Hemizygia ornata, synonymized under H. welwitschii in recent treatments of the genus Hemizygia, differentiates from H. welwitschii on the basis of differences in leaf and floral characters and its reinstatement at specific level is here proposed. The concept of H. linearis is revised on account of the type specimen separating from all other elements of the taxon used in the analyses. The latter form a coherent group with H. petrensis and H. canescens thus negating any attempt to give any of them specific recognition. It is proposed that they should be synonymized under the earliest name H. canescens. The specific boundary of H. petiolata is revised but its specific status maintained.