Leaf anatomy of Medicinal Shrubs and Trees from Gallery Forests of the Paranaense Province (Argentina): Part 1

sixty two species of shrubs and trees belonging to 28 families inhabiting gallery forests of the paranaense biogeographic province (argentina) have been cited with medicinal properties. the aim of this study was to provide a tool to recognize these taxa from fragmented leaf samples. fresh material and hydrated herbarium specimens fixed in faa were surveyed. the main differential traits are: hypodermis presence (e.g. myrceugenia glaucescens ); stomata and trichome types (e.g. ciclocytic stomata in baccharis spp.; cystolith-like structure in trichomes in aloysia gratissima var. gratissima ); midvein transection outlines (e.g. midvein convex and keel-shaped on the adaxial side in allophylus edulis ), mesophyll of the leaf blade (e.g. indifferentiated in poiretia tetraphylla ); presence of idioblastic sclereids (e.g. in the petiole of rollinia emarginata ), presence and types of crystals (e.g. crystal sand in sambucus australis ); presence of secretory structures (e.g. large secretory cavities in malvaceae and myrtaceae). we can conclude that the leaf features have diagnostic value to identify species. as a result, we offer a key to distinguish these 62 species and illustrations to clarify it. ecological interpretation of leaf structures is also given.