Palynological studies in the family Melastomataceae from Thailand

The pollen morphology of 86 species belonging to 19 genera of the Melastomataceae in Thailand was examined by both light-and scanning electron microscopy. Three pollen groups and five pollen types could be established: Group 1 has one type, Pternandra type, with tricolporate pollen. Group 2 comprises two heterocolpate pollen types with subsidiary colpi, the Anerincleistus and the Diplectria types and Group 3 comprises two heterocolpate pollen types, the Blastus and the Pachycentria types, with intercolpar concavities. A key for the identification of these pollen types as well as the possible phylogenetic trends is presented.