ABSTRACT
Anadenanthera is a genus of arborescent legumes that currently consists of two species, A. peregrina (L.) Speg. and A. colubrina (Veil.) Brenan. Each of these has two varieties: A. peregrina (L.) Speg. var. peregrina von Reis Alt. and A. peregrina (L.) Speg. var. falcata (Benth.) von Reis Alt. A. colubrina (Veil.) Brenan var. colubrina von Reis Alt. and A. colubrina (Veil.) Brenan var. Cebil (Griseb.) von Reis Alt. Originally classified by Bentham (1840) as section Niopo of the much larger genus Piptadenia, the species of Anadenanthera differ sufficiently in a number of morphological characters to warrant separate classification. Among these are flower structures, such as presence or lack of anther glands and shape of anthers, and pod or seed characteristics such as dehiscence of pods along one suture, or suborbicular seeds, narrow or not winged, lacking endosperm. Elements of wood anatomy, including the presence of nonseptate fibers and wide, typically 4-to 5-seriate rays, also serve to separate Anadenanthera from Piptadenia. In addition, Reis Altschul (1964) distinguished the two species of Anadenanthera based on the presence or absence of anther glands, the position of the involucre surrounding the peduncle, pod texture, and geographical location.
