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Abstract BackgroundLucilia cuprina(Wiedemann, 1830) (Diptera: Calliphoridae) is the main causative agent of flystrike of sheep in Australia and New Zealand. Female flies lay eggs in an open wound or natural orifice, and the developing larvae eat the host’s tissues, a condition called myiasis. To improve our understanding of host-seeking behavior, we quantified gene expression in male and female antennae based on their behavior. MethodsA spatial olfactometer was used to evaluate the olfactory response ofL. cuprinamated males and gravid females to fresh or rotting beef. Antennal RNA-Seq analysis was used to identify sensory receptors differentially expressed between groups. ResultsLucilia cuprinafemales were more attracted to rotten compared to fresh beef (> fivefold increase). However, males and some females did not respond to either type of beef. RNA-Seq analysis was performed on antennae dissected from attracted females, non-attracted females and males. Transcripts encoding sensory receptors from 11 gene families were identified above a threshold (≥ 5 transcript per million) including 49 ATP-binding cassette transporters (ABCs), two ammonium transporters (AMTs), 37 odorant receptors (ORs), 16 ionotropic receptors (IRs), 5 gustatory receptors (GRs), 22 odorant-binding proteins (OBPs), 9 CD36-sensory neuron membrane proteins (CD36/SNMPs), 4 chemosensory proteins (CSPs), 4 myeloid lipid-recognition (ML) and Niemann-Pick C2 disease proteins (ML/NPC2), 2pickpocketreceptors (PPKs) and 3 transient receptor potential channels (TRPs). Differential expression analyses identified sex-biased sensory receptors. ConclusionsWe identified sensory receptors that were differentially expressed between the antennae of both sexes and hence may be associated with host detection by female flies. The most promising for future investigations were as follows: an odorant receptor (LcupOR46) which is female-biased inL. cuprinaandCochliomyia hominivoraxCoquerel, 1858; an ABC transporter (ABC G23.1) that was the sole sensory receptor upregulated in the antennae of females attracted to rotting beef compared to non-attracted females; a female-biased ammonia transporter (AMT_Rh50), which was previously associated with ammonium detection inDrosophila melanogasterMeigen, 1830. This is the first report suggesting a possible role for ABC transporters inL. cuprinaolfaction and potentially in other insects. Graphical Abstract 

Abstract Decaying wood, while an abundant and stable resource, presents considerable nutritional challenges due to its structural rigidity, chemical recalcitrance, and low nitrogen content. Despite these challenges, certain insect lineages have successfully evolved saproxylophagy (consuming and deriving sustenance from decaying wood), impacting nutrient recycling in ecosystems and carbon sequestration dynamics. This study explores the uneven phylogenetic distribution of saproxylophagy across insects and delves into the evolutionary origins of this trait in disparate insect orders. Employing a comprehensive analysis of gut microbiome data, from both saproxylophagous insects and their non‐saproxylophagous relatives, including new data from unexplored wood‐feeding insects, this Hypothesis paper discusses the broader phylogenetic context and potential adaptations necessary for this dietary specialization. The study proposes the “Detritivore‐First Hypothesis,” suggesting an evolutionary pathway to saproxylophagy through detritivory, and highlights the critical role of symbiotic gut microbiomes in the digestion of decaying wood. 

IntroductionWood digestion in insects relies on the maintenance of a mosaic of numerous microhabitats, each colonized by distinct microbiomes. Understanding the division of digestive labor between these microhabitats- is central to understanding the physiology and evolution of symbiotic wood digestion. A microhabitat that has emerged to be of direct relevance to the process of lignocellulose digestion is the surface of ingested plant material. Wood particles in the guts of some termites are colonized by a specialized bacterial fiber-digesting microbiome, but whether this represents a widespread strategy among insect lineages that have independently evolved wood-feeding remains an open question. MethodsIn this study, we investigated the bacterial communities specifically associated with wood fibers in the gut of the passalid beetleOdontotaenius disjunctus. We developed a Percoll-based centrifugation method to isolate and enrich the wood particles from the anterior hindgut, allowing us to access the wood fibers and their associated microbiome. We then performed assays of enzyme activity and used short-read and long-read amplicon sequencing of the 16S rRNA gene to identify the composition of the fiber-associated microbiome. ResultsOur assays demonstrated that the anterior hindgut, which houses a majority of the bacterial load, is an important site for lignocellulose digestion. Wood particles enriched from the anterior hindgut contribute to a large proportion of the total enzyme activity. The sequencing revealed thatO. disjunctus, like termites, harbors a distinct fiber-associated microbiome, but notably, its community is enriched in insect-specific groups ofLactococcusandTuricibacter. DiscussionOur study underscores the importance of microhabitats in fostering the complex symbiotic relationships between wood-feeding insects and their microbiomes. The discovery of distinct fiber-digesting symbionts inO. disjunctus, compared to termites, highlights the diverse evolutionary paths insects have taken to adapt to a challenging diet. 

Abstract The New World Screwworm, Cochliomyia hominivorax (Calliphoridae), is the most important myiasis-causing species in America. Screwworm myiasis is a zoonosis that can cause severe lesions in livestock, domesticated and wild animals, and occasionally in people. Beyond the sanitary problems associated with this species, these infestations negatively impact economic sectors, such as the cattle industry. Here, we present a chromosome-scale assembly of C. hominivorax’s genome, organized in 6 chromosome-length and 515 unplaced scaffolds spanning 534 Mb. There was a clear correspondence between the D. melanogaster linkage groups A–E and the chromosomal-scale scaffolds. Chromosome quotient (CQ) analysis identified a single scaffold from the X chromosome that contains most of the orthologs of genes that are on the D. melanogaster fourth chromosome (linkage group F or dot chromosome). CQ analysis also identified potential X and Y unplaced scaffolds and genes. Y-linkage for selected regions was confirmed by PCR with male and female DNA. Some of the long chromosome-scale scaffolds include Y-linked sequences, suggesting misassembly of these regions. These resources will provide a basis for future studies aiming at understanding the biology and evolution of this devastating obligate parasite. 

Abstract 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 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. 

Ophthalmomyiasis is the result of fly larvae feeding on the tissues of the eye. Commonly associated with poor hygiene and open wounds, this condition is rare and often stigmatized. Treatment can be straightforward, and full recovery is common. Identifying the species responsible for ophthalmomyiasis is important for the medical, forensic, and entomological communities. Here, we present a case of ophthalmomyiasis where 30–40 blow fly (Diptera: Calliphoridae) larvae were removed from the eye of a human male. A representative subsample of five larvae was used for taxonomic identification via two approaches (a) DNA analysis, via sequencing of the complete mitochondrial genome (mtGenome) and comparison of the mtGenome and mitochondrial COI barcode region to GenBank, and (b) morphology, examination of the posterior spiracles using microscopy, and comparison to published larval descriptions of blow flies. Two species of blow flies were identified from the DNA analysis: Lucilia coeruleiviridis and Phormia regina. Morphological examination could only confirm L. coeruleiviridis as being present. To our knowledge, finding two blow fly species causing ophthalmomyiasis in a single individual has not been previously reported in the scientific literature. Neither P. regina nor L. coeruleiviridis prefers living tissue for larva development, but since they fill similar ecological niches, perhaps this was a show of competition rather than a normal feeding habit. Knowing these blow fly species can resort to this behavior, and that it can affect human populations, is valuable to the education of patients and providers. 

Improving science literacy is crucial amidst global challenges like climate change, emerging diseases, AI, and rampant disinformation. This is vital not only for future STEM generations but for all, to make informed decisions. Informal science communication efforts such as podcasts, popular science articles, and museum events are an essential part of the infrastructure for mobilizing knowledge and nurturing science literacy. However, in thisPerspective, we emphasize the need to grow our capacity for STEM outreach in the formal K-12 classroom. While the majority of informal outreach mechanisms require audience members to seek out content, classrooms include those hard-to-reach target audiences that are not already STEM-engaged. We contrast the multitude of resources that have been developed to support informal outreach in recent decades with a relative paucity of such efforts in the K-12 formal classroom realm. We advocate for a more balanced deployment of resources and efforts between these two vital components of our knowledge mobilization and STEM engagement infrastructure. In particular, we highlight the key role of K-12 teachers as conduits for knowledge dissemination and the need for greater collaboration between scientists and teachers at individual and organizational levels. We also advocate for greater collaboration across programs in both the informal and formal outreach space, and dedicated effort to construct dissemination networks to share outreach materials at scale across disparate programs. The aim of our piece is to generate discussion about how we might refocus goals, funding mechanisms, and policies to grow the science-engaged society necessary to confront future challenges. 

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.