Pollen Morphological Study on Some Species of Kickxia, Scrophularia in Relation to Plantago from Saudi Arabia

Pollen grains of ten species of Kickxia (Plantaginaceae, previously assigned to Scrophulariaceae), two species of Scrophularia (Scrophulariaceae) and one species of genus Plantago (Plantaginaceae) in Saudi Arabia were studied using both light and scanning electron microscopy. The most obvious findings in Plantago major are: Pantoporate pollen class (5–9), pollen shape class prolate—spheroidal, a polar, pollen shape—circular, circumaperture, apocolpium—absent, aperture type—annular and pollen wall sculpture—verrucate. This result showed that Plantago major was separated by their pollen morphological characteristics away from the other two studied genera. This result supports some taxonomic views of some scientists in maintaining Plantago species in a separate monogeneric family (Plantaginaceae) and keeping Kickxia and Scrophularia within the Scrophulariaceae family.