Raddia is an herbaceous bamboo genus with nine species in Brazil, one of which extends beyond Brazilian borders. The leaf anatomy of these species was analyzed using optical and scanning electron microscopy, in order to obtain useful characters for the taxonomy of the genus. Other herbaceous bamboos were used for comparison and no characters exclusive to Raddia were found. Leaf anatomy traits had little to do with species delimitation within the genus, sometimes separating only groups of species. Of these traits, the most important were as follows, in transverse section: form of the midrib, position of the intermediate vascular bundle, number of vascular bundles adjacent to the intermediate bundle and form of the fusoid cells. A surface view of the epidermis (SEM) showed differences among the species as regards occurrence, density and distribution of the papillae. Raddia megaphylla R.P. Oliveira & Longhi-Wagner and R. guianensis (Brongn.) Hitchc. & Chase had the largest number of exclusive characters of the species studied. A type of trichome unknown in Bambusoideae was recorded for R. stolonifera R.P. Oliveira & Longhi-Wagner.
anatomy; bamboos; Bambusoideae; Olyreae; Raddia; Gramineae
