Taxonomic significance of trichomes in the genus Acanthopsis Harv. (Acanthaceae, tribe Acantheae)

Hitherto characters derived mostly from macromorphology were used to distinguish among the members of Acanthopsis Harv., a taxonomically difficult group plants endemic arid parts southern Africa. The taxonomic significance leaf and bract indumentum in was investigated using light, scanning electron microscopy. Five non-glandular three glandular trichome types distinguished on leaves floral bracts. None these are unique genus. Although is variable Acanthopsis, density/dominance specific useful certain taxa, particularly abaxial surfaces Each species has characteristic complement as far dominant both bracts concerned. However, no obvious association between type trichomes habitat (degree aridity) or geographical distribution evident.