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Measuring species richness of tropical forests is a major challenge. Such measurement is a key information in many senses, from an evolutionary perspective to conservation of threatened, fragile habitats. Data has gradually shown that the canopy of tropical forest is a hugely complex component of the forest, but a precise assessment of the diversity of megadiverse groups in the canopy is still wanting. We collected large samples of insects were along a period of two weeks using 6-meter Gressitt-style Malaise traps set at five heights on a metal tower in a tropical forest north of Manaus—one trap at the ground level, one trap above the canopy (32 m) and three traps at intermediate levels (8, 16 and 24 m). The samples contained 37,778 specimens belonging to 18 order of insects. Fifty-seven families of flies (Diptera) were found, 39 of which were identified to 368 genera and 856 species. The species of these 39 families of flies fit into eight patterns of vertical distribution of abundance and species richness of the fauna, with patterns of one or two peaks of species at different levels. A total of 527 (61.6%) of the 856 fly species recognized in the samples were not collected at the ground level. The canopy-associated species of Diptera showed a high species richness and a relatively low abundance indicating that they represent vulnerable components of tropical diversity. The biology of the flies families and genera we collected in the canopy suggest that the evolution of flies went through a unique process: independent clades of Diptera explored in different ways the resources originated along the very evolution of the angiosperm forest canopy along the early Cenozoic. Unlike other primarily phytophagous groups of insects, flies radiated into a large array of biologies associated with the canopies: parasitoids, hematophagous, phytosaprophagous, kleptoparasites, sap feeders, gall-makers etc. The results only stress the need of additional strategies to protect this diversity.

The fauna of blowflies (Calliphoridae and Mesembrinellidae) in three localities of primary Amazon forest coverage in the Amazonas-Negro interfluvial region was assessed. A total of 5066 blowflies were collected, with Chloroprocta idiodea being the most abundant species (66.3%). A difference in species richness between the localities ZF2 and Novo Airão was observed. Comparison among sampled sites revealed no considerable variation in fauna composition, except for the species Eumesembrinella benoisti (Séguy 1925) and Hemilucilia sp., whose occurrence was observed only in a single locality. Apparently, Amazon rivers are not efficient geographical barriers to influence the current composition of necrophagous blowfly assemblages. Also, most of the blowfly species did not show a noticeable specificity for any specific forest among the interfluvial areas of the ombrophilous forest. Finally, an updated checklist of necrophagous blowfly species of the Amazonas state in Brazil is presented. Keywords: Blowfly assemblage, Calliphoridae, Diversity, Forensic entomology, Mesembrinellidae

Calyptrate flies include about 22,000 extant species currently classified into Hippoboscoidea (tsetse, louse, and bat flies), the muscoid grade (house flies and relatives) and the Oestroidea (blow flies, bot flies, flesh flies, and relatives). Calyptrates are abundant in nearly all terrestrial ecosystems, often playing key roles as decomposers, parasites, parasitoids, vectors of pathogens, and pollinators. For oestroids, the most diverse group within calyptrates, definitive fossils have been lacking. The first unambiguous fossil of Oestroidea is described based on a specimen discovered in amber from the Dominican Republic. The specimen was identified through digital dissection by CT scans, which provided morphological data for a cladistic analysis of its phylogenetic position among extant oestroids. The few known calyptrate fossils were used as calibration points for a molecular phylogeny (16S, 28S, CAD) to estimate the timing of major diversification events among the Oestroidea. Results indicate that: (a) the fossil belongs to the family Mesembrinellidae, and it is identified and described as Mesembrinella caenozoica sp. nov.; (b) the mesembrinellids form a sister clade to the Australian endemic Ulurumyia macalpinei (Ulurumyiidae) (McAlpine’s fly), which in turn is sister to all remaining oestroids; (c) the most recent common ancestor of extant Calyptratae lived just before the K–Pg boundary (ca. 70 mya); and (d) the radiation of oestroids began in the Eocene (ca. 50 mya), with the origin of the family Mesembrinellidae dated at ca. 40 mya. These results provide new insight into the timing and rate of oestroid diversification and highlight the rapid radiation of some of the most diverse and ecologically important families of flies. ZooBank accession number–urn:lsid:zoobank.org:pub:0DC5170B-1D16-407A-889E-56EED3FE3627.

BackgroundThe genotype-phenotype interactions among traits governing feeding preference are of fundamental importance to behavioral genetics and evolutionary biology. The genetic basis of behavioral traits has been explored in different taxa using different approaches. However, the complex nature of the genetic mechanisms undergirding behavior is poorly understood. Here, we present an evolutionary study of candidate genes related to parasitism in Calliphoridae (Diptera: Calyptratae). Closely related species in this family exhibit distinct larval feeding habits, most notably necro-saprophagy and obligate parasitism.MethodsTo understand the genetic and molecular bases underlying these habits, expression levels of eight candidate genes for feeding behavior—Cyp6g2, foraging, glutamate dehydrogenase, Jonah65aiv, Malvolio, PGRP-SC2,RPS6-p70-protein kinase,andsmooth—were measured in four species using qPCR. Moreover we used expression values and sequence information to reconstruct the relationship among species and thedN/dSrate to infer possible sites under selection.ResultsFor most candidate genes, no statistically significant differences were observed, indicating a high degree of conservation in expression. However,Malvoliowas differentially expressed between habits. Evolutionary analyses based on transcript levels and nucleotide sequences ofMalvoliocoding region suggest that transcript levels were correlated to feeding habit preferences among species, although deviations under a strictly neutral model were also observed in statistical tests.DiscussionMalvoliowas the only gene demonstrating a possible connection to feeding habit. Differences in gene expression may be involved in (or be a result of) the genetic regulation of Calliphoridae feeding habit. Our results are the first steps towards understanding the genetic basis and evolution of feeding behavior in Calliphoridae using a functional approach.

True flies are insects of the order Diptera and encompass one of the most diverse groups of animals on Earth. Within dipterans, Schizophora represents a recent radiation of insects that was used as a model to develop a pipeline for generating complete mitogenomes using various sequencing platforms and strategies. 91 mitogenomes from 32 different species were sequenced and assembled with high fidelity, using amplicon, whole genome shotgun or single molecule sequencing approaches. Based on the novel mitogenomes, we estimate the origin of Schizophora within the Cretaceous-Paleogene (K-Pg) boundary, about 68.3 Ma. Detailed analyses of the blowfly family (Calliphoridae) place its origin at 22 Ma, concomitant with the radiation of grazing mammals. The emergence of ectoparasitism within calliphorids was dated 6.95 Ma for the screwworm fly and 2.3 Ma for the Australian sheep blowfly. Varying population histories were observed for the blowfly Chrysomya megacephala and the housefly Musca domestica samples in our dataset. Whereas blowflies (n = 50) appear to have undergone selective sweeps and/or severe bottlenecks in the New World, houseflies (n = 14) display variation among populations from different zoogeographical zones and low levels of gene flow. The reported high-throughput mitogenomics approach for insects enables new insights into schizophoran diversity and population history of flies.