Lallemantia is a small genus of Lamiaceae with five herbaceous annual or biennial species. Some of these species are of medicinal value, while others have been used as the source of food. All five Lallemantia species occur in Iran. Although, there are many discussions about infra-generic variations in the genus, very scarce comprehensive studies are found about its taxonomy. Therefore, in the current study, pollen grain morphology was investigated using scanning electron microscopy. We used SPSS ver. 15 and PAST ver. 2.17 for multivariate statistical analyses of data. In total, we studied eleven qualitative and quantitative traits. Pollen equatorial and polar views were similar among the species and were prolate and circular, respectively. Pollen ornamentations differed as bireticulate (L. royleana and L. iberica), microreticulatm (L. peltata and L. Baldshuanica) and reticulate- faveolate (L. canescens). PCA-biplot showed some traits such as pori length/width ratio were important in identifications of species. The studied species created two groups in the WARD method tree of palynological data. L. royleana and L. baldshuanica were grouped together, and in the other group L. canescens and L. iberica placed nearly and L. peltata placed far from them. Our obtained results were similar to previous morphological study of the genus. The present study revealed taxonomic implication of the micromorphological study in the interspecific classification of the genus.
