A synopsis of the genus Medicago (Leguminosae)

Abstract

The genus Medicago has recently undergone extensive taxonomic changes. At least two dozen species not previously accepted as belonging to it have been added. Moreover, the circumscription, infraspecific taxonomy, and nomenclature of many of the species placed in Medicago have been altered recently, and the circumscription and nomenclature of the sections of the genus have also changed. Adding to the need for a synopsis is the fact that many of the species are very difficult to identify. This conspectus presents a key to the 12 sections and eight subsections of the genus, a comprehensive illustrated key to the 83 species (and 18 infraspecific taxa) of Medicago, and brief notes on their geography, ecology, and possible confusion with similar species.