Morphological and Ultrastructural Diversity of Orbicules in Gentianaceae

Morphological and ultrastructural diversity of orbicules in Gentianaceae

Minute granules of sporopollenin, called orbicules, can be observed on the walls of tapetum cells. Vinckier and Smets (pp. 657-672) investigate orbicules in 53 Gentianaceae species, covering all different tribes and subtribes recently recognized in the family by Struwe et al. (2002). The systematic usefulness of orbicule data is discussed in comparison with the latest systematic insights into the make up of the Gentianaceae.