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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. 

One of the key objectives in biological research is understanding how evolutionary processes have produced Earth’s diversity. A critical step toward revealing these processes is an investigation of evolutionary tradeoffs—that is, the opposing pressures of multiple selective forces. For millennia, nocturnal moths have had to balance successful flight, as they search for mates or host plants, with evading bat predators. However, the potential for evolutionary trade-offs between wing shape and body size are poorly understood. In this study, we used phylogenomics and geometric morphometrics to examine the evolution of wing shape in the wild silkmoth subfamily Arsenurinae (Saturniidae) and evaluate potential evolutionary relationships between body size and wing shape. The phylogeny was inferred based on 782 loci from target capture data of 42 arsenurine species representing all 10 recognized genera. After detecting in our data one of the most vexing problems in phylogenetic inference—a region of a tree that possesses short branches and no “support” for relationships (i.e., a polytomy), we looked for hidden phylogenomic signal (i.e., inspecting differing phylogenetic inferences, alternative support values, quartets, and phylogenetic networks) to better illuminate the most probable generic relationships within the subfamily. We found there are putative evolutionary trade-offs between wing shape, body size, and the interaction of fore- and hindwing (HW) shape. Namely, body size tends to decrease with increasing HW length but increases as forewing (FW) shape becomes more complex. Additionally, the type of HW (i.e., tail or no tail) a lineage possesses has a significant effect on the complexity of FW shape. We outline possible selective forces driving the complex HW shapes that make Arsenurinae, and silkmoths as a whole, so charismatic. [Anchored hybrid enrichment; Arsenurinae; geometric morphometrics; Lepidoptera; phylogenomics; Saturniidae.]

 

We performed a molecular phylogenetic analysis on the family Euteliidae to clarify deep divergences and elucidate evolutionary relationships at the level of the subfamily, tribe, and genus. Our dataset consists of 6.3 kbp of one mitochondrial and seven nuclear DNA loci and was analysed using model‐based phylogenetic methods, that is, maximum likelihood and Bayesian inference. Based on the recovered topology, we recognize two subfamilies, Euteliinae and Stictopterinae, and the tribes Stictopterini and Odontini. We identify apomorphic morphological character states for Euteliidae and its component subfamilies and tribes. Several genera (e.g.,Targalla, Paectes, Marathyssa, Eutelia) were found polyphyletic and require taxonomic revision. Two new genera (NiklasteliaZahiri & Hollowaygen.nov.andPellinenteliaHolloway & Zahirigen.nov.) are described and a number of taxonomic changes (new combinations and new synonymies) are established. The Neotropical genusThyriodes, currently included in Euteliidae, is found to be associated with Erebinae (Erebidae). The divergence time estimate for the split between the Euteliidae and Noctuidae is at 53 Ma, and the Euteliidae subfamilies Euteliinae and Stictopterinae are estimated to have diverged at 42 Ma. In Stictopterinae, the tribes Stictopterini and Odontodini split at 31 Ma, while Euteliinae began diversifying at 34 Ma. Malpighiales are inferred to have been the ancestral larval hostplant order for Euteliidae. The ancestors of Stictopterinae also appear to have been Malpighiales feeders, but then diverged to Malvales specialists (Odontodini) and Malpighiales specialists (Stictopterini) hostplants. Larvae of Stictopterini appear to be restricted primarily to Clusiaceae, apart from a few records from Dipterocarpaceae. In Euteliinae, Anacardiaceae are predominant as larval hosts. Thus, all hosts in the family are lactiferous, possibly providing some degree of pre‐adaptation for exploiting Dipterocarpaceae.

 

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.