COMPARATIVE ANATOMY OF LEAF AND SPATHE OF NINE SPECIES OF ANTHURIUM (SECTION UROSPADIX; SUBSECTION FLAVESCENTIVIRIDIA) (ARACEAE) AND THEIR DIAGNOSTIC POTENTIAL FOR TAXONOMY

ABSTRACT Leaf and spathe anatomy of seven species and two varieties of the genus Anthurium (section Urospadix; subsection Flavescentiviridia) were analyzed. Plant material was collected from different locations in Brazil and cultivated under identical glasshouse conditions in the Rio de Janeiro Botanical Garden. Our attempt is to evaluate the diagnostic potential of leaf and spathe anatomy for taxonomic purposes. Leaves presented smooth cuticle, polygonal epidermal cells randomly disposed in paradermal view, periclinal divisions of epidermal cells in transversal view, non-raised stomata, collenchyma, sclerenchymatic bundle sheaths and raphides in the mesophyll. The spathe presented cuticular striations; rectangular and elongated cells in parallel rows; raised stomata; absence of collenchyma, raphides and sclerenchymatic bundle sheaths and presence of sclerenchyma as fibre caps under phloem. Clustering analysis based on leaf and spathe anatomical characters, revealed that the spathe can give a better resolution for segregation of species groups