Transoceanic origin of microendemic and flightless New Caledonian weevils

• Main Authors: Emmanuel F. A. Toussaint, Rene Tänzler, Michael Balke, Alexander Riedel
• Format: Article
• Language: English
• Published: The Royal Society 2017-01-01
• Series: Royal Society Open Science
• Subjects: biogeobears; flightless beetle biogeography; curculionidae; long-distance dispersal; melanesia; trigonopterus
• Online Access: https://royalsocietypublishing.org/doi/pdf/10.1098/rsos.160546

The origin of the astonishing New Caledonian biota continues to fuel a heated debate among advocates of a Gondwanan relict scenario and defenders of late oceanic dispersal. Here, we study the origin of New Caledonian Trigonopterus flightless weevils using a multimarker molecular phylogeny. We infer two independent clades of species found in the archipelago. Our dating estimates suggest a Late Miocene origin of both clades long after the re-emergence of New Caledonia about 37 Ma. The estimation of ancestral ranges supports an ancestral origin of the genus in a combined region encompassing Australia and New Guinea with subsequent colonizations of New Caledonia out of New Guinea in the mid-Miocene. The two New Caledonian lineages have had very different evolutionary trajectories. Colonizers belonging to a clade of foliage dwellers greatly diversified, whereas species inhabiting leaf-litter have been less successful.