Comparative pollen morphology of Turkish species of Petrorhagia (Caryophyllaceae) and its systematic implications

Pollen morphology of 10 taxa from Turkey, four of them endemic, belonging to the genus Petrorhagia (Caryophyllaceae), P. alpina subsp. alpina, P. alpina subsp. olympica, P. cretica, P. dubia, P. hispidula, P. lycica, P. pamphylica, P. peroninii, P. prolifera and P. saxifraga, has been investigated using light (LM) and scanning electron (SEM) microscopy. Pollen morphology differences among these taxa have been determined. The pollen type of investigated taxa is polyporate (12–22-porate), sphaeroidal, the exine exhibits a tectate structure and a microechinate ornamentation. Petrorhagia alpina subsp. alpina has the smallest pollen grain diameter (18.57 μm) and P. dubia the largest one (37.80 μm). The number of pores ranges from 12 (in P. dubia and P. saxifraga) to 22 (in P. alpina subsp. alpina and P. alpina subsp. olympica and P. hispidula) with a minimum pore diameter of 2.37 μm in P. alpina subsp. alpina and a maximum pore diameter of 4.23 μm in P. peroninii. The exine thickness ranges from 1.73 μm in P. saxifraga to 3.78 μm in P. pamphylica. In this study, the systematic implications are discussed in the light of palynological results.