Combined Data, Bayesian Phylogenetics, and the Origin of the New Zealand Cicada Genera

Abstract.—We have applied Bayesian and maximum likelihood methods of phylogenetic estimation to data from fourmitochondrial genes (COI, COII, 12S, and 16S) and a single nuclear gene (EF1®) from several genera of NewZealand, Australian, andNewCaledonian cicada taxa.We specically focused on the heterogeneity of phylogenetic signal among the different data partitions and the biogeographic origins of the New Zealand cicada fauna. The Bayesian analyses circumvent many of the problems associated with other statistical tests for comparing data partitions. We took an information-theoretic approach tomodel selection basedon theAkaike InformationCriterion (AIC).This approach indicated that there was considerable uncertainty in identifying the best-t model for some of the partitions. Additionally, a large amount of uncertainty was associated with many parameter estimates from the substitution model. However, a sensitivity analysis on the combined dataset indicated that the model selection uncertainty had little effect on estimates of topology because these estimates were largely insensitive to changes in the assumed model. This outcome suggests strong signal in our data. Our analyses support a New Caledonian afliation of the New Zealand cicada generaMaoricicada, Kikihia, and Rhodopsalta and Australian afnities for the genera Amphipsalta and Notopsalta. This result was surprising, given that previous cicada biologists suspected a close relationship between Amphipsalta