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Abstract Fungus weevils (family Anthribidae) are morphologically and ecologically diverse, with highly varied feeding habits, mainly mycetophagy but also phytophagy, palynophagy and entomophagy. The phylogeny of the family is virtually unexplored, its evolutionary history obscure; thus, the existing classification is controversial and likely artificial. We generated the first multi‐gene higher‐level phylogeny estimate of Anthribidae using DNA data from 400 nuclear genes obtained via anchored hybrid enrichment from 40 species representing 17 tribes plus generaincertae sedis. As in previous studies, the family Anthribidae was consistently recovered as the sister group of Nemonychidae. We recovered two main clades in Anthribidae as sister groups with strong statistical support, viz. a monophyletic subfamily Urodontinae and the traditionally recognized Anthribinae, which was rendered paraphyletic by the subfamily Choraginae. Paraphyly and polyphyly among tribes of Anthribinae indicate that current tribal concepts—all based on morphology and without phylogenetic analysis—are artificial. Based on our results, we subsume the subfamily Choraginae into Anthribinae and place its six current tribes (Apolectini, Araecerini, Choragini, Cisanthribini, Valenfriesiini and Xenorchestini) in an expanded subfamily Anthribinae. We also transfer three genera currently treated as Anthribinaeincertae sedisto three generally recognized tribes, namelyPleosporiusHolloway to Sintorini,XylanthribusKuschel to Proscoporhinini andAnthribidusFåhraeus to Platystomini. The phylogenetic positions of Urodontinae and Trigonorhinini suggest that phytophagy is the ancestral feeding mode of Anthribidae, with a few taxa of Anthribinae having secondarily evolved plant‐feeding from mycetophagy, the predominant feeding habit of the subfamily. Overall, our results provide the first molecular phylogenetic context for research on Anthribidae and a first step towards reconstructing a natural tribal classification of the Anthribinae. Our study highlights the need for a phylogenetic approach, sampling of type genera and deeper taxon sampling to identify natural tribal‐level groupings. 

The rise of angiosperms to ecological dominance and the breakup of Gondwana during the Mesozoic marked major transitions in the evolutionary history of insect-plant interactions. To elucidate how contemporary trophic interactions were influenced by host plant shifts and palaeogeographical events, we integrated molecular data with information from the fossil record to construct a time tree for ancient phytophagous weevils of the beetle family Belidae. Our analyses indicate that crown-group Belidae originated approximately 138 Ma ago in Gondwana, associated with Pinopsida (conifer) host plants, with larvae likely developing in dead/decaying branches. Belids tracked their host plants as major plate movements occurred during Gondwana’s breakup, surviving on distant, disjunct landmasses. Some belids shifted to Angiospermae and Cycadopsida when and where conifers declined, evolving new trophic interactions, including brood-pollination mutualisms with cycads and associations with achlorophyllous parasitic angiosperms. Extant radiations of belids in the generaRhinotia(Australian region) andProterhinus(Hawaiian Islands) have relatively recent origins. 

Abstract The Diaprepes root weevil (DRW), Diaprepes abbreviatus, is a broadly polyphagous invasive pest of agriculture in the southern United States and the Caribbean. Its genome was sequenced, assembled, and annotated to study genomic correlates of specialized plant-feeding and invasiveness and to facilitate the development of new methods for DRW control. The 1.69 Gb D. abbreviatus genome assembly was distributed across 653 contigs, with an N50 of 7.8 Mb and the largest contig of 62 Mb. Most of the genome was comprised of repetitive sequences, with 66.17% in transposable elements, 5.75% in macrosatellites, and 2.06% in microsatellites. Most expected orthologous genes were present and fully assembled, with 99.5% of BUSCO genes present and 1.5% duplicated. One hundred and nine contigs (27.19 Mb) were identified as putative fragments of the X and Y sex chromosomes, and homology assessment with other beetle X chromosomes indicated a possible sex chromosome turnover event. Genome annotation identified 18,412 genes, including 43 putative horizontally transferred (HT) loci. Notably, 258 genes were identified from gene families known to encode plant cell wall degrading enzymes and invertases, including carbohydrate esterases, polysaccharide lyases, and glycoside hydrolases (GH). GH genes were unusually numerous, with 239 putative genes representing 19 GH families. Interestingly, several other beetle species with large numbers of GH genes are (like D. abbreviatus) successful invasive pests of agriculture or forestry. 

The regions of the Andes and Caribbean-Mesoamerica are both hypothesized to be the cradle for many Neotropical lineages, but few studies have fully investigated the dynamics and interactions between Neotropical bioregions. The New World hawkmoth genus Xylophanes is the most taxonomically diverse genus in the Sphingidae, with the highest endemism and richness in the Andes and Caribbean-Mesoamerica. We integrated phylogenomic and DNA barcode data and generated the first time-calibrated tree for this genus, covering 93.8% of the species diversity. We used event-based likelihood ancestral area estimation and biogeographic stochastic mapping to examine the speciation and dispersal dynamics of Xylophanes across bioregions. We also used trait-dependent diversification models to compare speciation and extinction rates of lineages associated with different bioregions. Our results indicate that Xylophanes originated in Caribbean-Mesoamerica in the Late Miocene, and immediately diverged into five major clades. The current species diversity and distribution of Xylophanes can be explained by two consecutive phases. In the first phase, the highest Xylophanes speciation and emigration rates occurred in the Caribbean-Mesoamerica, and the highest immigration rates occurred in the Andes, whereas in the second phase the highest immigration rates were found in Amazonia, and the Andes had the highest speciation and emigration rates. 

Abstract Butterflies are a diverse and charismatic insect group that are thought to have evolved with plants and dispersed throughout the world in response to key geological events. However, these hypotheses have not been extensively tested because a comprehensive phylogenetic framework and datasets for butterfly larval hosts and global distributions are lacking. We sequenced 391 genes from nearly 2,300 butterfly species, sampled from 90 countries and 28 specimen collections, to reconstruct a new phylogenomic tree of butterflies representing 92% of all genera. Our phylogeny has strong support for nearly all nodes and demonstrates that at least 36 butterfly tribes require reclassification. Divergence time analyses imply an origin ~100 million years ago for butterflies and indicate that all but one family were present before the K/Pg extinction event. We aggregated larval host datasets and global distribution records and found that butterflies are likely to have first fed on Fabaceae and originated in what is now the Americas. Soon after the Cretaceous Thermal Maximum, butterflies crossed Beringia and diversified in the Palaeotropics. Our results also reveal that most butterfly species are specialists that feed on only one larval host plant family. However, generalist butterflies that consume two or more plant families usually feed on closely related plants.