An acount of the Plantaginaceae of Thailand

Abstract

One genus, with a single native species, is recognised in the Plantaginaceae following revision of Thai and associated materials. Plantago comprises the widespread P. major which is taken to include P. asiatica (lectotypified here) and P. erosa (lectotypified here). Investigation of stomatal density, stomatal length, seed size, seed number, leaf-lobing, pseudo-pedicel presence, inter-flower spacing and corolla-lobe length revealed that only the latter showed significant difference between material usually assigned to P. asiatica and P. major; with the latter the larger. The detected difference is both small and the reverse of that expected from previous studies.
Though field experience suggests that P. major is fairly frequent throughout Thailand the number of collections housed in herbaria is very few and the distributional data given are, necessarily, incomplete.