Pollen morphology of some Gypsophila L. (Caryophyllaceae) species and its taxonomic value

Pollen morphology of 12 taxa (6 of them endemic) that belong to the genus Gypsophila L. were investigated using light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM).Differences in pollen morphology between these taxa were determined based on palynological studies. Pollen grains are spheroidal and polyporate. The exine structure is tectate, but that of G. sphaerocephala var. sphaerocephala is intectate.The exine sculpture is granulate-microechinate-microperforate, but that of G. sphaerocephala var. sphaerocephala displaysclavate-microechinate ornamentation. The operculum exists in the form of scattered pieces in G. curvifolia, while it existsas a whole in the other taxa. G. perfoliata var. perfoliata has the largest pollen grain diameter, whereas G. tubulosa has the smallest. The exine consists of 2 parts; the upper part is the thick ectexine and the lower part is the thin endexine. The endexine is thin and continuous.