Mutisieae (Asteraceae) Pollen Ultrastructure Atlas

Abstract

The tribe Mutisieae (excluding Barnadesieae) traditionally comprises 84 genera and approximately 900 species in three subtribes: Gochnatiinae, Mutisiinae, and Nassauviinae. We examined whole and fractured pollen grains of 51 genera from these subtribes by scanning electron microscopy (SEM) and light microscopy (LM). Additionally, we also examined 11 genera (Adenocaulon, Berardia, Brachylaeana, Cra- tystylis, Dipterocome, Eriachaenium, Gymnarrhena, Hesperomannia, Hoplophyllum, Tarchonanthus, and Warionia) whose tribal positions have been controversial. We present detailed tables of pollen characters for each taxon and 13 plates of SEM photos ofrepresentative taxa. We also provide limited discussion of pollen variation in the subbribes Gochnatiinae, Mutisiinae, and Nassauviinae and the tribal and sub- familial placement of the 11 problematic genera.