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Abstract It is widely recognized that different regions of a genome often have different evolutionary histories and that ignoring this variation when estimating phylogenies can be misleading. However, the extent to which this is also true for morphological data is still largely unknown. Discordance among morphological traits might plausibly arise due to either variable convergent selection pressures or else phenomena such as hemiplasy. Here we investigate patterns of discordance among 282 morphological characters, which we scored for 50 bee species particularly targeting corbiculate bees, a group that includes the well-known eusocial honeybees and bumblebees. As a starting point for selecting the most meaningful partitions in the data, we grouped characters as morphological modules, highly integrated trait complexes that as a result of developmental constraints or coordinated selection we expect to share an evolutionary history and trajectory. In order to assess conflict and coherence across and within these morphological modules, we used recently developed approaches for computing Bayesian phylogenetic information allied with model comparisons using Bayes factors. We found that despite considerable conflict among morphological complexes, accounting for among-character and among-partition rate variation with individual gamma distributions, rate multipliers, and linked branch lengths can lead to coherent phylogenetic inference using morphological data. We suggest that evaluating information content and dissonance among partitions is useful step in estimating phylogenies from morphological data, just as it is with molecular data. Furthermore, we argue that adopting emerging approaches for investigating dissonance in genomic datasets may provide new insights into the integration and evolution of anatomical complexes. 

Abstract Rasopone Schmidt and Shattuck is a poorly known lineage of ants that live in Neotropical forests. Informed by phylogenetic results from thousands of ultraconserved elements (UCEs) and mitochondrial DNA barcodes, we revise the genus, providing a new morphological diagnosis and a species-level treatment. Analysis of UCE data from many Rasopone samples and select outgroups revealed non-monophyly of the genus. Monophyly of Rasopone was restored by transferring several species to the unrelated genus Mayaponera Schmidt and Shattuck. Within Rasopone, species are morphologically very similar, and we provide a ‘bird guide’ approach to identification rather than the traditional dichotomous key. Species are arranged by size in a table, along with geographic range and standard images. Additional diagnostic information is then provided in individual species accounts. We recognize a total of 15 named species, of which the following are described as new species: R. costaricensis, R. cryptergates, R. cubitalis, R. guatemalensis, R. mesoamericana, R. pluviselva, R. politognatha, R. subcubitalis, and R. titanis. An additional 12 morphospecies are described but not formally named due to insufficient material. Rasopone panamensis (Forel, 1899) is removed from synonymy and elevated to species. The following species are removed from Rasopone and made new combinations in Mayaponera: M. arhuaca (Forel, 1901), M. becculata (Mackay and Mackay, 2010), M. cernua (Mackay and Mackay, 2010), M. conicula (Mackay and Mackay, 2010), M. longidentata (Mackay and Mackay, 2010), and M. pergandei (Forel, 1909).