A Revision of the Genus Stylosanthes

Abstract

The genus Stylosanthes was established in 1788 by O. Swartz! with two species, S. procumbens (= S. hamata (L.) Taub.) and S. viscosa.Previous to the founding of the genus, most present-day species of Stylosanthes had been referred to other genera.Linnaeus? in 1753 had described Trifolium biflorum (= S. biflora (L.) BSP.) and in 17593 Hedysarum hamatum B (= S. viscosa Sw.) ; in 1775 Aublet* had named Trifolium guinanense (= S. guyanensis (Aubl.)Sw.).Preceding the advent of the binomial system, a few polynomials had been applied to modern species of Stylosanthes.Apparently the first mention of a species now known to belong to the genus was in 1696 when Sir Hans Sloane?listed Anonis non spinosa, minor, glabra, procumbens, flore lutea as occurring in Jamaica.This is S. hamata (L.) Taub.In 1737 Burmann?recorded Trifolium procumbens zeylanicum hirsutum (= S. fruticosa (Retz.)Mohlenbrock).Willdenow, in the fourth edition of 'Species Plantarum',* listed five species of Stylosanthes.G. Don? in 1832 listed thirteen species.Of these, however, only seven have proved to be distinct, and three of these were recorded without usage of the earliest epithet applicable.The first study of Stylosanthes was a synopsis by Vogel® in 1838.He divided the genus into two sections, EUSTYLOSANTHES and STYPOSANTHES, based on the absence or presence, respectively, of an axis rudiment (an aborted secondary axis associated with each flower).An unfortunate situation has arisen, however, since Vogel designated S. procumbens Sw. (-S.hamata (L.) Taub.) of $ sTYPOSAN-THES to be the type species.According to present nomenclatorial rules, the section or subgenus including the type species must repeat the generic name, hence Vogel's $ srYPOsANTHES must be changed to § STYLOSANTHES; his $ EUSTYLOSANTHES here is renamed § ASTYPOSANTHES.In his section including species without axis rudiments, Vogel recorded eight species, three of them new, while in the other section, seven species are listed including four new ones.All seven of Vogel's new