Systematics of genistoid legumes: taxonomy and phylogeny of Argyrolobium (Genisteae, Fabaceae)
ID: 613 / 464
Proposed Symposium Title: Systematics of genistoid legumes: taxonomy and phylogeny of Argyrolobium (Genisteae, Fabaceae)
J. Stephen Boatwright1, Brian du Preez2, Xichavo Mathebula1, Marianne M. le Roux 3,4
Affiliations: 1 Department of Biodiversity and Conservation Biology, University of the Western Cape, Cape Town, South Africa 2 Department of Biological Sciences, University of Cape Town, Cape Town, South Africa 3 Foundational Biodiversity Sciences Division, Pretoria National Herbarium, South African National Biodiversity Institute, Pretoria, South Africa 4 Department of Botany and Plant Biotechnology, University of Johannesburg, Johannesburg, South Africa
The genus Argyrolobium Eckl. & Zeyh. (Genisteae) comprises of ca. 97 species distributed throughout tropical and northern Africa, Madagascar, the Mediterranean, southern Europe and west into the highlands of India. It has its centre of diversity in southern Africa where about 51 species occur. Phylogenetic studies based on a limited sampling of the genus have indicated that the genus may not be monophyletic, and that the generic circumscription needs revision. In addition, the South African species (47) have only been treated synoptically in recent years, based on an unpublished Ph.D. thesis, and the last published comprehensive taxonomic revision of the southern African species dates back to 1862. Several new species remain to be described, and difficult species complexes renders identification of some species problematic. The present study is aimed at producing morphological and molecular data for Argyrolobium, based on a globally representative sampling, that will contribute towards resolving the generic circumscription and relationships of the genus. In addition, the taxonomy of the southern African species will be revised. Data from the analysis of nuclear and plastid DNA sequences confirm that the genus is not monophyletic. While a large clade of predominantly southern African species was recovered, the remaining tropical African, Middle Eastern, Asian and Malagasy species form at least two separate clades distributed among other genera of the Genisteae. Options for generic circumscriptions will be explored. An overview of the taxonomy of the genus will also be presented, along with progress on revisions of several groups within the genus.