Abstract

Acanthospermum hispidum and Acanthospermum australe (Asteraceae) are widely distributed in arid regions, in northeastern Brazil, and the first specie is used in folk medicine as anti‑asthmatic while the second specie as antiseptic, anti-inflammatory and diuretic. They are often confounded and used indifferently for the same medicinal purposes due to both having similar morphological characteristics. The aim of this work was to carry out a macro and microscopical investigation to characterize the vegetative organs, including the macerate of both species. The plant material was collected, fixed and processed according to usual light microscopy techniques. A short-petiole in A. hispidum is a diagnostic trait that distinguish it from A. australe. Types of glandular trichomes can distinguish these two species. The different types of xylem vessels found in root, stem and leaf of both species identify the presence of one of them into raw drug. These findings will be useful in establishing pharmacognostic and phytochemical standards for identification, as well as assessment of accuracy to avoid contamination and insure quality control, which definitely is gaining relevance in plant drug research and establishment of plant monograph.

Key words: Acanthospermum hispidum, Acanthospermum austral, anti-asthmatic, macerate, traditional medicine, folk medicine, Brazil.