Next‐generation sequencing technologies (NGS) allow systematists to amass a wealth of genomic data from non‐model species for phylogenetic resolution at various temporal scales. However, phylogenetic inference for many lineages dominated by non‐model species has not yet benefited from NGS, which can complement Sanger sequencing studies. One such lineage, whose phylogenetic relationships remain uncertain, is the diverse, agriculturally important and charismatic Coreoidea (Hemiptera: Heteroptera). Given the lack of consensus on higher‐level relationships and the importance of a robust phylogeny for evolutionary hypothesis testing, we use a large data set comprised of hundreds of ultraconserved element (UCE) loci to infer the phylogeny of Coreoidea (excluding Stenocephalidae and Hyocephalidae), with emphasis on the families Coreidae and Alydidae. We generated three data sets by including alignments that contained loci sampled for at least 50%, 60%, or 70% of the total taxa, and inferred phylogeny using maximum likelihood and summary coalescent methods. Twenty‐six external morphological features used in relatively comprehensive phylogenetic analyses of coreoids were also re‐evaluated within our molecular phylogenetic framework. We recovered 439–970 loci per species (16%–36% of loci targeted) and combined this with previously generated UCE data for 12 taxa. All data sets, regardless of analytical approach, yielded topologically similar and strongly supported trees, with the exception of outgroup relationships and the position of Hydarinae. We recovered a monophyletic Coreoidea, with Rhopalidae highly supported as the sister group to Alydidae + Coreidae. Neither Alydidae nor Coreidae were monophyletic; the coreid subfamilies Hydarinae and Pseudophloeinae were recovered as more closely related to Alydidae than to other coreid subfamilies. Coreinae were paraphyletic with respect to Meropachyinae. Most morphological traits were homoplastic with several clades defined by few, if any, synapomorphies. Our results demonstrate the utility of phylogenomic approaches in generating robust hypotheses for taxa with long‐standing phylogenetic problems and highlight that novel insights may come from such approaches.

Assassin bugs (Reduvioidea) are one of the most diverse (>7,000 spp.) lineages of predatory animals and have evolved an astounding diversity of raptorial leg modifications for handling prey. The evolution of these modifications is not well understood due to the lack of a robust phylogeny, especially at deeper nodes. We here utilize refined data from transcriptomes (370 loci) to stabilize the backbone phylogeny of Reduvioidea, revealing the position of major clades (e.g., the Chagas disease vectors Triatominae). Analyses combining transcriptomic and Sanger-sequencing datasets result in the first well-resolved phylogeny of Reduvioidea. Despite amounts of missing data, the transcriptomic loci resolve deeper nodes while the targeted ribosomal genes anchor taxa at shallower nodes, both with high support. This phylogeny reveals patterns of raptorial leg evolution across major leg types. Hairy attachment structures (fossula spongiosa), present in the ancestor of Reduvioidea, were lost multiple times within the clade. In contrast to prior hypotheses, this loss is not directly correlated with the evolution of alternative raptorial leg types. Our results suggest that prey type, predatory behavior, salivary toxicity, and morphological adaptations pose intricate and interrelated factors influencing the evolution of this diverse group of predators.

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Sacrificing body parts is one of many behaviors that animals use to escape predation. This trait, termed autotomy, is classically associated with lizards. However, several other taxa also autotomize, and this trait has independently evolved multiple times throughout Animalia. Despite having multiple origins and being an iconic antipredatory trait, much remains unknown about the evolution of autotomy. Here, we combine morphological, behavioral, and genomic data to investigate the evolution of autotomy within leaf-footed bugs and allies (Insecta: Hemiptera: Coreidae + Alydidae). We found that the ancestor of leaf-footed bugs autotomized and did so slowly; rapid autotomy (<2 min) then arose multiple times. The ancestor likely used slow autotomy to reduce the cost of injury or to escape nonpredatory entrapment but could not use autotomy to escape predation. This result suggests that autotomy to escape predation is a co-opted benefit (i.e., exaptation), revealing one way that sacrificing a limb to escape predation may arise. In addition to identifying the origins of rapid autotomy, we also show that across species variation in the rates of autotomy can be explained by body size, distance from the equator, and enlargement of the autotomizable appendage. K E Y W O R D S : Autotomy, evolutionary ecology, evolutionary origins, latitudinal gradient, phylogenetic comparative methods, predator-prey.

Baits targeting invertebrate ultraconserved elements (UCEs) are becoming more common for phylogenetic studies. Recent studies have shown that invertebrate UCEs typically encode proteins—and thus, are functionally different from more conserved vertebrate UCEs—and can resolve deep divergences (e.g., superorder to family ranks). However, whether invertebrate UCE baits have the power to robustly resolve relationships at shallower phylogenetic scales has been generally limited to investigations within the Coleoptera and Hymenoptera; thus, there are many invertebrate UCE baits that remain to be tested at shallower levels (i.e., tribes and congeners). Here, we assessed the ability of a recently designed Hemiptera UCE bait set to reconstruct more recent phylogenetic relationships in the largest leaf-footed bug subfamily, the Coreinae (Hemiptera: Coreidae), using a taxon-rich sample representing 21 of the 32 coreine tribes. Many well-supported, novel relationships were congruent in maximum likelihood and summary coalescent analyses. We also found evidence for the para- and polyphyly of several tribes and genera of Coreinae, as well as the subfamilies Coreinae and Meropachyinae. Our study, along with other recent UCE studies, provides evidence that UCEs can produce robust and novel phylogenetic hypotheses at various scales in invertebrates.

Abstract. Ectrichodiinae (Hemiptera: Reduviidae), the millipede assassin bugs, are a speciose group (>660 species) of assassin bugs that appear to be specialist predators on Diplopoda, or millipedes. Apparently capable of coping with the noxious defensive compounds produced by many millipedes, Ectrichodiinae are engaged in a predator-prey relationship with millipedes realized only by few other arthropods. Unfortunately, feeding behaviors of Ectrichodiinae are inadequately documented, rendering this exciting phenomenon largely inaccessible. We here present a literature review on ectrichodiine prey selection and feeding behaviors, with supplemental original observations on Rhiginia cinctiventris (Stål, 1872) in Costa Rica. Thirteen species in 12 genera have been observed to feed on millipedes. The majority of diplopod prey species were reported from the orders Spirostreptida and Spirobolida, whereas Polydesmida are rarely attacked. Ectrichodiinae insert their stylets at the millipede's intersegmental membranes on the ventral and ventro-lateral trunk area or between the head and collum. Communal predation was observed among conspecific nymphs, among groups of nymphs with a conspecific adult, and more rarely among adults. Immature ectrichodiines were rarely observed to engage in solitary predation. Observations on R. cinctiventris indicate that this species preys on spirobolid and polydesmid millipedes and are in agreement with behaviors described for other Ectrichodiinae.

Evolution of sexual dimorphism in animals has long been of interest to scientists, but relatively few studies have reconstructed evolutionary patterns of extreme sexual dimorphism at a phylogenetic scale, especially in insects. Millipede assassin bugs (Heteroptera: Reduviidae: Ectrichodiinae; 736 spp.) and their sister taxon, Tribelocephalinae (150 spp.), exhibit sexual dimorphism that ranges from limited to extreme, a phenomenon apparently modulated by female morphology. Here, we reconstruct the first phylogeny for the subfamilies Ectrichodiinae and Tribelocephalinae with comprehensive generic representation (152 taxa in 72 genera) using morphological and molecular data (six gene regions). The combined phylogenetic results indicate that Tribelocephalinae are paraphyletic with respect to Ectrichodiinae, and that Ectrichodiinae themselves are polyphyletic. Based on these results, we synonymize Tribelocephalinae with Ectrichodiinae syn.n., describe three new tribes (Ectrichodiini trib.n., Tribelocodiini trib.n., and Abelocephalini trib.n.) and two new subtribes (Opistoplatyina subtrib.n. and Tribelocephalina subtrib.n.), and revise Tribelocephalini sensu n. Ancestral state reconstruction of sexual dimorphism reconstructed limited sexual dimorphism in the ancestor of Ectrichodiinae sensu n. with at least seven evolutionary transitions to extreme sexual dimorphism within the clade. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:C810E20F-D66A-461F-A0E6-AB1073EA3E3C.

For at least the past 80my, Madagascar, a major biodiversity hotspot, has been isolated from all other landmasses. This long-term isolation, along with geologic and climatic factors within Madagascar and throughout the Indian Ocean, has undoubtedly influenced the evolution of the island's biota. However, few systematic analyses incorporating modern divergence dating and biogeographic analyses have focused on Madagascan insects. The diverse Madagascan millipede assassin bugs (Heteroptera: Reduviidae: Ectrichodiinae) offer an opportunity to contribute to a limited body of insect-related research that explores Madagascar's historical biogeography. A molecular dataset (COI mtDNA and 18S, 28S D2 and D3-D5 rDNAs) for 56 taxa (39 ingroup) and a combined morphological (145 characters) and molecular dataset for 110 taxa (93 ingroup) are analyzed with maximum likelihood (ML) and parsimony approaches. Based on the molecular ML phylogeny, divergence times were estimated using fossil and secondary calibrations and biogeographic analyses performed using DIVA, DEC, and DEC+j models to determine the role and patterns of vicariance and dispersal in the origin of Madagascan Ectrichodiinae. Results indicate that Ectrichodiinae in Madagascar do not form a monophyletic group, different clades are closely related to Afrotropical and Oriental lineages, and have colonized the island via transoceanic dispersal at least twice from the Oriental region and once from the Afrotropical region in the last ∼68my. Additionally, the DEC+j and DIVA models infer a single out-of-Madagascar dispersal event to the Afrotropical region. Oceanic and geologic factors that may have facilitated dispersal between these three regions are discussed. Results of the combined analyses are used to explore character support for Madagascan taxa and inform taxonomic diagnoses. Our results are congruent with the small but growing body of biogeographic research supporting Cenozoic transoceanic dispersal for Madagascan invertebrates to and from Oriental and Afrotropical regions.