Abstract

The foliar anatomy of 12 species of Asteraceae around Ile Ife in South Western, Nigeria was described. The distinguishing characteristics of taxonomic value include; venation patterns, areole shapes, number of veinlet endings, trichome types, arrangement of vascular bundles. Venation types are actinodromous, craspedodromous or camptodromous, the presence of rectangular areoles are predominant in the species studied and this show family characteristics. However, the presence of crystal druses in the areoles of C. odorata is of diagnostic importance. The type of vascular bundle in the leaf midribs is classificatory as it divided the taxa studied into two groups; vascular bundles are amphicribal in Bidens pilosa, Chromolaena odorata, Launaea taraxacifolia, Crassocephalum crepidiodes, Tridax procumbens and Vernonia cinerea and bicollateral in Ageratum conyzoides, Aspilia africana, Emilia praetermissa, Synedrella nodiflora, Tithonia diversifolia and Vernonia amygdalina.

Key words: Asteraceae, foliar, taxonomic, venation, areole.