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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. 

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.

 

The frenulum is a wing coupling structure that is found on the wings of most families of Lepidoptera. It is a single bristle or set of bristles that originate from the base of the hindwing that often interlocks with the forewing during flight. This wing coupling mechanism is thought to have been a major evolutionary innovation that allowed for enhanced flight in Lepidoptera. The sack‐bearer moths (Mimallonidae) are unusual among Lepidoptera in that not all species within the family have a frenulum. We test the hypothesis that the frenulum is not necessary and is therefore lost in mimallonids that have longer male forewings, because such wings are perhaps better suited to be coupled by other means. To understand the evolution of the frenulum, we inferred the most taxonomically and genetically sampled anchored hybrid enrichment‐based phylogeny of Mimallonidae, including 604 loci from all 41 genera and from 120 species, covering about 40% of the described species in the family. The maximum likelihood tree robustly supports major relationships within the family, and ancestral state reconstruction clearly recovers the frenulum as the plesiomorphic condition in Mimallonidae. Our results show that the frenulum is more often observed in species that have shorter, rather than longer, male forewings. The frenulum has historically been used as an important character for intrafamilial classification in Mimallonidae, but our results conclusively show that this character system is more variable than previously thought. Based on our results, we erect two new subfamilies, Roelofinae St Laurent & Kawahara,subfam.n.and Meneviinae St Laurent, Herbin, & Kawahara,subfam.n., for four genera previously consideredincertae sedis.In the predominantly frenulum‐lacking clade Cicinninae, we describe a new genus,CerradocinnusSt Laurent, Mielke, & Kawahara,gen.n., and the genusGonogrammastat. rev.is revalidated to include many species previously placed inCicinnussensu lato. With these changes,Cicinnuscan now be considered monophyletic. Thirty‐three species are transferred toGonogrammafromCicinnussensu lato.

This published work has been registered on Zoobank,http://zoobank.org/urn:lsid:zoobank.org:pub:E33100E1‐DA6A‐4814‐A312‐36CBAA168B8B.

 

Gracillariidae is the most taxonomically diverse cosmopolitan leaf‐mining moth family, consisting of nearly 2000 named species in 105 described genera, classified into eight extant subfamilies. The majority of gracillariid species are internal plant feeders as larvae, creating mines and galls in plant tissue. Despite their diversity and ecological adaptations, their phylogenetic relationships, especially among subfamilies, remain uncertain. Genomic data (83 taxa, 589 loci) were integrated with Sanger data (130 taxa, 22 loci), to reconstruct a phylogeny of Gracillariidae. Based on analyses of both datasets combined and analyzed separately, monophyly of Gracillariidae and all its subfamilies, monophyly of the clade “LAMPO” (subfamilies: Lithocolletinae, Acrocercopinae, Marmarinae, Phyllocnistinae, and Oecophyllembiinae) and relationships of its subclade “AMO” (subfamilies: Acrocercopinae, Marmarinae, and Oecophyllembiinae) were strongly supported. A sister‐group relationship of Ornixolinae to the remainder of the family, and a monophyletic leaf roller lineage (CallicercopsVári + Parornichinae) + Gracillariinae, as sister to the “LAMPO” clade were supported by the most likely tree. Dating analyses indicate a mid‐Cretaceous (105.3 Ma) origin of the family, followed by a rapid diversification into the nine subfamilies predating the Cretaceous–Palaeogene extinction. We hypothesize that advanced larval behaviours, such as making keeled or tentiform blotch mines, rolling leaves and galling, allowed gracillariids to better avoid larval parasitoids allowing them to further diversify. Finally, we stabilize the classification by formally re‐establishing the subfamily ranks of Marmarinaestat.rev., Oecophyllembiinaestat.rev. and Parornichinaestat.rev., and erect a new subfamily, Callicercopinae Li, Ohshima and Kawahara to accommodate the enigmatic genusCallicercops.