New Taxa in Piptocarpha R. Br. (Vernonieae: Compositae)

Abstract

The general distribution and striking features of Piptocarpha are discussed. Three new species and one subspecies are described and figured: Piptocarpha jonesiana G. L. Smith and P. opaca (Benth.) Baker subsp. piraparandensis G. L. Smith from southeastern Colombia; P. barrosoana G. L. Smith and P. prancei G. L. Smith from Brazil. A neotropical genus of approximately 45 species, Piptocarpha extends from southern Brazil and northern Argentina into the West Indies and Central America. The major center of distribution is southern and eastern Brazil but secondary centers are the northern and central Andes, the Venezuelan Guayana Highland and the Amazon River Basin. Striking field features of the genus are the axillary inflorescences, which frequently take the form of dense globose glomerules, and the scandent habit of many species. The scandent species usually form dense thickets or climb high in trees. Other species are trees, these largely distributed in the highlands of southern Brazil. Important contributions to our understanding of Piptocarpha in the twentieth century have been made from Colombia by Cuatrecasas (1955), from Venezuela by Aristeguitea (1964, 1967), and from Brazil by Barroso (1959, 1969) and Cabrera (1961, 1964). These treatments have been of considerable value in the comprehensive revision of Piptocarpha, currently in progress at the University of Georgia. As some time must elapse before my full revision is published, I here describe one new species and one subspecies from Colombia and two new species from