Late Cenozoic diversification of the austral genus Lagenophora (Astereae, Asteraceae)

• Published in: Botanical Journal of the Linnean Society
• Main Authors: Sancho, Gisela, de Lange, Peter J., Donato, Mariano Humberto, Barkla, John, Wagstaff, Steve J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley Blackwell Publishing, Inc
• Subjects: ANTARCTICA; AUSTRAL DISTRIBUTIONS; DIVERGENCE TIMES; MOLECULAR DATING; MOLECULAR PHYLOGENY; NEW ZEALAND; SOUTH AMERICA; Ciencias de las Plantas; Botánica; Ciencias Biológicas; CIENCIAS NATURALES Y EXACTAS; Austral; Gough; New Zealand; Tristan; Antarc*; Antarctica
• Online Access: http://hdl.handle.net/11336/95081

Lagenophora (Astereae, Asteraceae) has 14 species in New Zealand, Australia, Asia, southern South America, Gough Island and Tristan da Cunha. Phylogenetic relationships in Lagenophora were inferred using nuclear and plastid DNA regions. Reconstruction of spatio‐temporal evolution was estimated using parsimony, Bayesian inference and likelihood methods, a Bayesian relaxed molecular clock and ancestral area and habitat reconstructions. Our results support a narrow taxonomic concept of Lagenophora including only a core group of species with one clade diversifying in New Zealand and another in South America. The split between the New Zealand and South American Lagenophora dates from 11.2 Mya [6.1–17.4 95% highest posterior density (HPD)]. The inferred ancestral habitats were openings in beech forest and subalpine tussockland. The biogeographical analyses infer a complex ancestral area for Lagenophora involving New Zealand and southern South America. Thus, the estimated divergence times and biogeographical reconstructions provide circumstantial evidence that Antarctica may have served as a corridor for migration until the expansion of the continental ice during the late Cenozoic. The extant distribution of Lagenophora reflects a complex history that could also have involved direct long‐distance dispersal across southern oceans.