Palynology of Acmadenia (Diosminae: Rutaceae) and its taxonomic implications

The palynology of Acmadenia (Diosminae: Rutaceae), a taxonomically problematic genus, was investigated to determine its taxonomic significance. Pollen of 32 of the 33 species, and one undescribed species, was investigated by LM, SEM and TEM techniques. Exine structure is extremely variable in proportion to the size of the genus, with seven distinct types and four subtypes being discerned. Species groupings elucidated by the pollen types suggest relationships between species which were not previously apparent. Pollen data supports morphological evidence for the re‐classification of Acmadenia. A redefined Acmadenia is proposed to consist of 23 species, whereas the remainder of the taxa should be referred to new or closely related existing genera.