SEM images of trichomes of Critoniopsis. A, B C. bogotana (Cuatrec.) H. Rob., unicellular trichomes showing elongate branch and short spur-like branches near base C, D C. tausae H. Rob. & S.C. Keeley, showing unicellular stellate form with short arms, one arm slightly longer than the other four D Two trichomes entangled with each other showing lack of elongate arms E C. narinoensis H. Rob. & S.C. Keeley, showing highly ramified and flattened form F C. glandulata (Cuatrec.) H. Rob., showing T-shaped trichome with multicellular stalk and transversely mounted cap-cell, also showing part of cap-cell of second trichome, cap-cells with thinner-walled distal surface caved-in as result of drying.