Indument characterization of nine Loasaceae species from Venezuela

Abstract

In this work the epidermal indumentum observed in different organs of 9 species of Loasaceae from Venezuela were characterized, emphasizing their type and location on the plant to establish their possible taxonomic significance. The indumentum was studied using optical and scanning electron microscopy. Two classes of indumentum were observed: trichomes and emergences. The trichomes were classified as uni- and multicellular, non-glandular trichomes, and multicellular glandular trichomes. The conical and uncinate glochidiate trichomes were common in all the species studied. Nasa was the genus with the greatest trichomes diversity. The occurrence of dendritic trichomes is reported for the first time, exclusively in Nasa venezuelensis. Leaves and ovaries are the organs with the greatest variety of appendices. Gronovia scandens is the only species with emergences, which are restricted to the stems. The morphology of the epidermal appendices is a character with diagnostic value at the subfamily level, which is demonstrated in the key.