New World Origins of Southwest Pacific Gesneriaceae: Multiple Movements Across and Within the South Pacific

A groundbreaking study challenges the long-held Gondwanan origin hypothesis for the Southwest Pacific Gesneriaceae, revealing instead that the tribe Coronanthereae originated in South America and dispersed across the South Pacific through multiple long-distance dispersal events. Phylogenetic analyses of nuclear and chloroplast DNA sequences, combined with ancestral-area reconstruction and molecular dating, identified three distinct subtribes within Coronanthereae: Negriinae (including Lenbrassia from Australia, Depanthus from New Caledonia, and Negria from Lord Howe Island), Mitrariinae (grouping Australian Fieldia with South American epiphytes), and Coronantherinae (encompassing Coronanthera from New Caledonia and Rhabdothamnus from New Zealand). The findings underscore the significance of long-distance dispersal mechanisms in shaping the geographic distribution of this unique plant group, rather than Gondwanan vicariance.

Woo, V. L., Funke, M. M., Smith, J. F., Lockhart, P. J., & Garnock-Jones, P. J. (2011). New World Origins of Southwest Pacific Gesneriaceae: Multiple Movements Across and Within the South Pacific. International Journal of Plant Sciences, 172(3), 434–457. https://doi.org/10.1086/658183