Pollen Morphology of the Three Species of the Genus Emilia CASS. (Asteraceae) from Nigeria
The structural morphology of the pollen grains of the three species of Emilia occurring in Nigeria is reported. The report is based on the study carried out with a light microscope on acetolysed pollen grains. Observations from this investigation show that E. coccinea with more acolpate and monocolpate pollen grains is the most primitive out of the three species studied. Tetracolpate pollen grain which is an advanced type of pollen grain was observed in E. praetermissa alone affirming that this taxon is more advanced than the other two taxa investigated. So based on this study, the order E.coccinea followed by E. sonchifolia followed by E. praetemissa in ascending order of recent evolutionary development is strongly affirmed. Moreover out of all the pollen -grain attributes statistically analysed, number of pores on the pollen grains is an attribute that can be used effectively and reliably to separate, delimit and classify the species of Ernilia.