Chapter 5.pdf - DSpace@UM

(iii) StriateIn this type, coarse striae form a meshwork over the trichome surface. This isonly found exclusively in R. macromera (Fig. 37H) and R. vietnamensis (Fig.37I).(iv) Minutely dippledThis type has minute depressions occurring all over the trichome surface.This can be found in R. wittii (Fig. 37J, Asian).In some taxa surveyed, the smooth and warty trichome surfaces can be foundin different individuals within the same species, e.g., R. attopevensis, R.pseudoternifolia var. hispida, R. pseudoternifolia var. pseudoternifolia (Fig. 37A),and R. schoemannii in Asia (see Table 12 for details).It can therefore be deduced that trichome ornamentation may not be useful indistinguishing genera very well. In Rothmannia, a diverse range of trichomeornamentation exists. In Kochummenia stenopetala (Fig 37F) and K. parviflora (Fig.37G), as well as R. macrophylla, the trichome ornamentation is warty, a conditionalso found in the majority of the Rothmannia species. In R. globosa, trichomes areabsent. Thus, trichome ornamentation is found to be of potential taxonomic utilityonly at the specific level.170