title: A dated phylogeny of the papilionoid legume genus Canavalia reveals recent diversification by a pantropical liana lineage.
abstract: Canavalia is a pantropical legume genus of lianas comprising approximately 60 species distributed in a wide range of habitats. In the last taxonomic revision, the genus was divided into four subgenera: Canavalia (Pantropical), Catodonia (Neotropical, excepting one species also found in the Old World), Maunaloa (Hawaiian), and Wenderothia (Neotropical). In this study, we reconstructed the phylogeny of Canavalia using a broad taxon sampling and analyses of nuclear (ETS and ITS) and plastid markers (trnK/matK). We evaluated the infrageneric classification of the genus and investigated its biogeographical history using molecular dating analyses and ancestral area reconstructions. The phylogenetic analyses resolved subgenus Wenderothia as monophyletic. Subgenus Catodonia needs to be recircumscribed and the relationships between subgenera Canavalia and Maunaloa remain unclear. Canavalia arose during the Miocene with a mean stem age estimate of 13.8Ma and mean crown age estimate of 8.7Ma, and most extant species evolved during the Pleistocene. Several climatic and geological events are chronologically coincident with the divergence of the major clades of Canavalia (glacial/interglacial periods, Andes uplift and the formation of Pebas and post-Pebas systems, closure of the Isthmus of Panama, and change in the direction of ocean currents). Ancestral area reconstructions for the early divergence of the genus are equivocal, although, some evidence suggests Canavalia originated in the wet forests of South America and achieved its current pantropical distribution through recent transoceanic dispersal. The evolution of Canavalia is better explained by a series of several processes than by discrete historical events.
authors: Universidade Estadual de Feira de Santana, Departamento de Ciências Biológicas, Av. Transnordestina, s/n, Novo Horizonte, Feira de Santana 44036-900, Bahia, Brazil. Electronic address: cristianesnak@gmail.com.
authors: Cristiane
authors: C
authors: Snak
authors: Department of Botany, National Museum of Natural History, MRC 166, Smithsonian Institution, Washington D.C. 20013-7012, USA; Department of Biology, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8-522, Japan. Electronic address: vatanparast@gmail.com.
authors: Mohammad
authors: M
authors: Vatanparast
authors: Universidade Estadual de Feira de Santana, Departamento de Ciências Biológicas, Av. Transnordestina, s/n, Novo Horizonte, Feira de Santana 44036-900, Bahia, Brazil. Electronic address: christian_da_silva@hotmail.com.
authors: Christian
authors: C
authors: Silva
authors: Comparative Plant and Fungal Biology Department, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, United Kingdom. Electronic address: g.lewis@kew.org.
authors: Gwilym Peter
authors: GP
authors: Lewis
authors: Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman 59717, USA. Electronic address: mlavin@montana.edu.
authors: Matt
authors: M
authors: Lavin
authors: Iriomote Station, Tropical Biosphere Research Center, University of the Ryukyus, Uehara, Takketomi-cho, Okinawa 907-1541, Japan. Electronic address: kajita@mail.ryudai.jp.
authors: Tadashi
authors: T
authors: Kajita
authors: Universidade Estadual de Feira de Santana, Departamento de Ciências Biológicas, Av. Transnordestina, s/n, Novo Horizonte, Feira de Santana 44036-900, Bahia, Brazil. Electronic address: luciano.paganucci@gmail.com.
authors: Luciano Paganucci de
authors: LP
authors: Queiroz
mesh_terms: D032449:Canavalia / Q000235:genetics*; D017753:Ecosystem; D019143:Evolution, Molecular; D010802:Phylogeny; D018087:Plastids / Q000235:genetics; D013020:South America
keywords: Ancestral area reconstruction; Biogeography; Diocleae; Isthmus of Panama; Leguminosae; Molecular dating