Review of palaeobotany and palynology vol:112 issue:4 pages:189-205
Pollen descriptions, based on LM and SEM observations, are provided for the Pentas complex, an African alliance within the Hedyotideae-Spermacoceae alliance, which includes the genera Pentas, Otomeria, Batopedina, Pauapentas, and Chamaepentas. The close relationship among these genera is confirmed by pollen morphological data. The observed variation in pollen character states agrees well with the existing genera and subgenera. The combination of small spheroidal pollen grains with narrow, acute endocolpi, and a small apocolpium index distinguishes Batopedina from Otomeria and Pentas. Parapentas differs from Batopedina in having broad endocolpi with vague ends.