Palynological insights into Albuca virens (Hyacinthaceae) with ultrastructural evidence for taxonomic reevaluation

Pollen micromorphology relations are provided by previous research in the Ornithogaloideae subfamily. The present research focused on the sporoderm characteristics of Albuca virens (syn: Stellarioides tenuifolia), Ornithogalum arcuatum (syn: Loncomelos arcuatum) and Ornithogalum sintenisii. The pollen ultrastructure of these species was examined using transmission electron microscopy (TEM). The results indicated that the pollen wall thickness of A. virens differed from that of the other taxa in some features such as ectexine, tectum, foot layer and intine layer thickness, the ratio of tectum to foot layer thickness (T/F ratio) and the measurements of the length and width of columellae. All the studied taxa had two intine layers in the sulcus membrane. The endexine state of A. virens was similar to that of O. arcuatum. In conclusion, the sporoderm data from this study support the taxonomical position of A. virens and its close relation to Ornithogalum taxa.