Pollen and trichome morphology of tribe Stachydeae (Lamiaceae) and its phylogenetic significance

In the present study, trichomes of 70 spp. from nine genera and pollens of 53 spp. from six genera were investigated using scanning electron microscopy (SEM) in order to draw the taxonomic conclusion of tribe Stachydeae. Trichome characters that can provide adequate variation in delimitation of taxa were: presence or absence of glandular or nonglandular trichomes, number of cells (uni-/bi-/multicellular), presence of extremely long trichomes (i.e. more than 1000 μm), presence of branched trichomes as well as type of glandular trichomes (peltate or capitate with three subtypes: sessile to subsessile, short-stalked and longstalked trichomes).