Discovery of new species of New Caledonian Arsipoda Erichson, 1842 (Coleoptera: Chrysomelidae) and insights on their ecology and evolution using DNA markers

Abstract

New Caledonia is among Earth's biodiversity hotspots, and we are far from knowing how many species it sustains. We applied DNA-based methods for quick biodiversity assessment of New Caledonian Arsipoda flea beetles, enhancing the discovery and description of new species. Mitochondrial DNA phylogenetic analysis (cox1, rrnS) for four out of five known neocaledonian taxa hints at the existence of additional species, and two are confirmed and described based on morphology: Arsipoda geographica Gómez-Zurita sp. nov. and Arsipoda rostrata Gómez-Zurita sp. nov. Timing this small radiation using standard insect mitochondrial substitution rates places its origin in the Miocene. A DNA-based approach to investigate potential food plants for these herbivorous insects reveals associations with Myrsinaceae and Ericaceae, which have not yet been found in New Caledonia, suggesting that this indirect methodology may help in discovering undetected flora. Traditional taxonomy and molecular approaches cooperate here, boosting our knowledge on species inventory and ecological interactions where it is most needed.

Keywords:

• Arsipoda
• Alticinae
• molecular ecology
• mitochondrial DNA phylogeny
• new species
• Pacific Islands
• taxonomy

Acknowledgements

Kjell-Arne Johanson (NRM, Stockholm, Sweden) and Christine Pöllabauer (ERBIO, Nouméa, Nouvelle-Calédonie) generously offered half of the samples of New Caledonian Arsipoda used in the phylogenetic analyses, and Lars Hendrich (ZSM, München, Germany) contributed the specimen of Australian Arsipoda used as the outgroup. Shepherd Myers (Bishop Museum, Honolulu, HI, USA) kindly provided photographs of Samuelson's New Caledonian types to confirm identifications. Hervé Jourdan (IRD, Nouméa, Nouvelle-Calédonie), Gaël Kergoat and Laurent Soldati (INRA, Montferrier-sur-Lez, France) shared difficult times with one of us (JAJR) at the Mt Kouakoué, the type locality of A. geographica Gómez-Zurita sp. nov., and Alain Queval, helicopter pilot, made it possible to reach this collecting site and, after several days, to return home safely amidst very bad weather conditions. The advice of Ignacio Ribera (IBE, Barcelona, Spain) helped us to improve this work in many respects. This project was funded by a Research Grant (no. 8380-07) of the Committee of Research and Exploration of the National Geographic Society, and also benefited from a travel grant from the Percy Sladen Memorial Fund of the Linnean Society of London.