Morphological Studies in the Genus Emilia (Senecioneae, Asteraceae)

Adedeji, Olubukola (2006)


A morphological study of the three species of Emilia Cass. in two different ploidy levels in Nigeria was performed. Both qualitative and quantitative characters were recorded. Characters of taxonomic value include the habit, bloom colour, colour and pubescence of the stem, differences in the margin of the leaves, corolla tube, style and stigma colours, pedicel length, capitulum length and breadth, the quantitative relationship of floret to involucral bracts, floret number, fruit number and size. E. praetermissa, the allotetraploid hybrid, is closely related to E. coccinea and E. sonchifolia – the other diploid relative. E. praetermissa has intermediate morphological and ecological characteristics. The morphological characters indicating E. praetermissa as an allotetraploid hybrid of E. coccinea and E. sonchifolia are bloom colour, corolla tube colour, and pedicel length. E. praetermissa behaves like a true allopolyploid in its habitat and ecological preferences. A new key to the Emilia species in Nigeria is included.