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Mosquitoes have profoundly affected human history and continue to threaten human health through the transmission of a diverse array of pathogens. The phylogeny of mosquitoes has remained poorly characterized due to difficulty in taxonomic sampling and limited availability of genomic data beyond the most important vector species. Here, we used phylogenomic analysis of 709 single copy ortholog groups from 256 mosquito species to produce a strongly supported phylogeny that resolves the position of the major disease vector species and the major mosquito lineages. Our analyses support an origin of mosquitoes in the early Triassic (217 MYA [highest posterior density region: 188–250 MYA]), considerably older than previous estimates. Moreover, we utilize an extensive database of host associations for mosquitoes to show that mosquitoes have shifted to feeding upon the blood of mammals numerous times, and that mosquito diversification and host-use patterns within major lineages appear to coincide in earth history both with major continental drift events and with the diversification of vertebrate classes.

 

The schizophoran superfamily Ephydroidea (Diptera: Cyclorrhapha) includes eight families, ranging from the well-known vinegar flies (Drosophilidae) and shore flies (Ephydridae), to several small, relatively unusual groups, the phylogenetic placement of which has been particularly challenging for systematists. An extraordinary diversity in life histories, feeding habits and morphology are a hallmark of fly biology, and the Ephydroidea are no exception. Extreme specialization can lead to “orphaned” taxa with no clear evidence for their phylogenetic position. To resolve relationships among a diverse sample of Ephydroidea, including the highly modified flies in the families Braulidae and Mormotomyiidae, we conducted phylogenomic sampling. Using exon capture from Anchored Hybrid Enrichment and transcriptomics to obtain 320 orthologous nuclear genes sampled for 32 species of Ephydroidea and 11 outgroups, we evaluate a new phylogenetic hypothesis for representatives of the superfamily. These data strongly support monophyly of Ephydroidea with Ephydridae as an early branching radiation and the placement of Mormotomyiidae as a family-level lineage sister to all remaining families. We confirm placement of Cryptochetidae as sister taxon to a large clade containing both Drosophilidae and Braulidae–the latter a family of honeybee ectoparasites. Our results reaffirm that sampling of both taxa and characters is critical in hyperdiverse clades and that these factors have a major influence on phylogenomic reconstruction of the history of the schizophoran fly radiation. 

The Miltogramminae (Diptera: Sarcophagidae) includes ~600 species across >40 genera, which constitute ~20% of global Sarcophagidae. While molecular phylogenetic hypotheses have been produced for this group, critical problems persist, including the presence of paraphyletic genera, uncertain relationships between genera, a bias of sampling towards Palaearctic taxa, and low support for many branches. The present study remedies these issues through the application of Anchored Hybrid Enrichment (AHE) to a sample including ~60% of the currently recognised genera (16% of known species) representing all biogeographic regions except the Neotropical. An alignment of 1,281 concatenated loci was analysed with maximum likelihood (RAxML, IQ‐TREE), Bayesian inference (ExaBayes) and coalescent‐based approaches (ASTRAL, SVDquartets), which resulted in highly supported and concordant topologies, providing unprecedented insight into the relationships of this subfamily of flesh flies, allowing a major update to miltogrammine classification. The AHE phylogenetic hypothesis supports the monophyly of a large proportion of genera. The monophyly ofMetopiaMeigen is restored by synonymy withAenigmetopiaMalloch,syn.n.To achieve monophyly ofMiltogrammaMeigen, eight species are transferred fromPterellaRobineau‐Desvoidy. The genusPterellais shown to be paraphyletic in its current circumscription, and to restore generic monophylyPterellais restricted to contain onlyPt. grisea(Meigen).ErioproctaEnderlein,stat.rev., is resurrected. The genusSenotainiaMacquart is reconstructed as paraphyletic. The monotypic genusMetopodiaBrauer & Bergenstamm is synonymised withTaxigrammaMacquart,syn.n.In light of our phylogenetic hypotheses, a new Miltogramminae tribal classification is proposed, composed of six tribes.

 

Abstract Background The most species-rich radiation of animal life in the 66 million years following the Cretaceous extinction event is that of schizophoran flies: a third of fly diversity including Drosophila fruit fly model organisms, house flies, forensic blow flies, agricultural pest flies, and many other well and poorly known true flies. Rapid diversification has hindered previous attempts to elucidate the phylogenetic relationships among major schizophoran clades. A robust phylogenetic hypothesis for the major lineages containing these 55,000 described species would be critical to understand the processes that contributed to the diversity of these flies. We use protein encoding sequence data from transcriptomes, including 3145 genes from 70 species, representing all superfamilies, to improve the resolution of this previously intractable phylogenetic challenge. Results Our results support a paraphyletic acalyptrate grade including a monophyletic Calyptratae and the monophyly of half of the acalyptrate superfamilies. The primary branching framework of Schizophora is well supported for the first time, revealing the primarily parasitic Pipunculidae and Sciomyzoidea stat. rev. as successive sister groups to the remaining Schizophora. Ephydroidea, Drosophila ’s superfamily, is the sister group of Calyptratae. Sphaeroceroidea has modest support as the sister to all non-sciomyzoid Schizophora. We define two novel lineages corroborated by morphological traits, the ‘Modified Oviscapt Clade’ containing Tephritoidea, Nerioidea, and other families, and the ‘Cleft Pedicel Clade’ containing Calyptratae, Ephydroidea, and other families. Support values remain low among a challenging subset of lineages, including Diopsidae. The placement of these families remained uncertain in both concatenated maximum likelihood and multispecies coalescent approaches. Rogue taxon removal was effective in increasing support values compared with strategies that maximise gene coverage or minimise missing data. Conclusions Dividing most acalyptrate fly groups into four major lineages is supported consistently across analyses. Understanding the fundamental branching patterns of schizophoran flies provides a foundation for future comparative research on the genetics, ecology, and biocontrol. 

Scientific collections such as the U.S. National Museum (USNM) are critical to filling knowledge gaps in molecular systematics studies. The global taxonomic impediment has resulted in a reduction of expert taxonomists generating new collections of rare or understudied taxa and these large historic collections may be the only reliable source of material for some taxa. Integrated systematics studies using both morphological examinations and DNA sequencing are often required for resolving many taxonomic issues but as DNA methods often require partial or complete destruction of a sample, there are many factors to consider before implementing destructive sampling of specimens within scientific collections. We present a methodology for the use of archive specimens that includes two crucial phases: 1) thoroughly documenting specimens destined for destructive sampling—a process called electronic vouchering, and 2) the pipeline used for whole genome sequencing of archived specimens, from extraction of genomic DNA to assembly of putative genomes with basic annotation. The process is presented for eleven specimens from two different insect subfamilies of medical importance to humans: Anophelinae (Diptera: Culicidae)—mosquitoes and Triatominae (Hemiptera: Reduviidae)—kissing bugs. Assembly of whole mitochondrial genome sequences of all 11 specimens along with the results of an ortholog search and BLAST against the NCBI nucleotide database are also presented. 

The genusLiriomyzaMik (Diptera: Agromyzidae) is a diverse and globally distributed group of acalyptrate flies. Phylogenetic relationships amongLiriomyzaspecies have remained incompletely investigated and have never been fully addressed using molecular data. Here, we reconstruct the phylogeny of the genusLiriomyzausing various phylogenetic methods (maximum likelihood, Bayesian inference, and gene tree coalescence) on target‐capture‐based phylogenomic datasets (nucleotides and amino acids) obtained from anchored hybrid enrichment (AHE). We have recovered tree topologies that are nearly congruent across all data types and methods, and individual clade support is strong across all phylogenetic analyses. Moreover, defined morphological species groups and clades are well‐supported in our best estimates of the molecular phylogeny.Liriomyza violivora(Spencer) is a sister group to all remaining sampledLiriomyzaspecies, and the well‐known polyphagous vegetable pests [L. huidobrensis(Blanchard),L. langeiFrick,L. bryoniae.(Kaltenbach),L. trifolii(Burgess),L. sativaeBlanchard, andL. brassicae(Riley)]. belong to multiple clades that are not particularly closely related on the trees. Often, closely relatedLiriomyzaspecies feed on distantly related host plants. We reject the hypothesis that cophylogenetic processes betweenLiriomyzaspecies and their host plants drive diversification in this genus. Instead,Liriomyzaexhibits a widespread pattern of major host shifts across plant taxa. Our new phylogenetic estimate forLiriomyzaspecies provides considerable new information on the evolution of host‐use patterns in this genus. In addition, it provides a framework for further study of the morphology, ecology, and diversification of these important flies.