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Phylogenetic relationships of theSphaerophorialineage (SphaerophoriaLe Peletier & Audinet-Serville and related genera) were inferred based on molecular characters, with the specific aim to infer the phylogenetic placement of the AfrotropicalSphaerophoriaspecies andLoveridgeana beattieivan Doesburg & van Doesburg. Three molecular markers were used, i.e., the mitochondrial protein-coding gene cytochrome c oxidase subunit I (COI) and the nuclear 28S and 18S ribosomal RNA genes. TheSphaerophorialineage generaExallandraVockeroth andLoveridgeanawere resolved within the genusSphaerophoria, and the IndomalayanEosphaerophoriaFrey was placed sister toCitrogrammaVockeroth, both related to a large species radiation from the New World.FaziaShannon andAllograptaOsten Sacken were recovered as non-monophyletic. Our results recovered two differentFaziaclades with dissimilar natural history resulted from our analyses, andAllograptaspecies were resolved into two clades, one with Nearctic and Neotropical species and a second clade with species from Oceanian, Indomalayan and Afrotropical Regions.Exallandrais considered a subgenus ofSphaerophoria,S. (Exallandra)stat. rev.,andSphaerophoria cinctifacies(Speiser)n. comb.a member of this subgenus together withS. loewiiZetterstedt. A newSphaerophoriasubgenus is designatedS.(Loveridgeana)stat. rev.to includeS. beattiein. comb.and the South African species, i.e.,S. quadrituberculataBezzi,S. retrocurvaHull, andS. aff.retrocurva. Based on their phylogenetic distinctiveness, functional traits, and ecological relevance we do recommend further ecological study and protection efforts for this Afrotropical group of pollinators.

Hoverflies (Syrphidae) represent an insect group of great importance in ecosystems and indicators of ecosystem change. The genus Merodon Meigen, 1803 (tribe Merodontini) is one of the most species-rich hoverfly genera, distributed across the Palaearctic and Afrotropical regions. The genus Merodon Meigen, 1803 is less diverse in the Afrotropical Region than in the Palaearctic (11 versus 160 known species). An ongoing study of the genus Merodon in Africa has revealed the existence of two new species into the taxon previously known as Merodon planifacies Bezzi, 1915. The M. planifacies subgroup belongs to the Afrotropical lineage of the Merodon desuturinus group. Morphological analysis of male genitalia has classified the available specimens of the M. planifacies taxon into two sets: the first one corresponds to M. planifacies with folded theca, while the other with smooth theca, later named Merodon capi complex was found exclusively at the Drakensberg mountains in the Republic of South Africa, specifically in the Cathedral Peak National Park and the Royal Natal National Park. Further, molecular and morphometric evidences revealed two cryptic taxa within this complex: M. capi sp. nov. Vujić et Radenković and Merodon roni sp. nov. Radenković et Vujić. This work was funded by a project of the European Union: Horizon 2020, Marie Skłodowska-Curie action, Research and Innovation Staff Exchange (RISE) Programme: FlyHigh - Insect-plant relationships: insights into biodiversity and new applications (project number 645636, 2015e2018); and partially by the RSA SAEON network, a member of International Long-Term Ecological Research Network (ILTER) and Ministry of Education, Science and Technological Development of the Republic of Serbia (OI173002, III43002, III44006, 451-03-68/2020-14/200358 and 451-03-68/2020-14/200125).

The phytophagous hoverfly genusMerodonMeigen, 1803 (Diptera, Syrphidae), which comprises more than 160 species distributed in Palaearctic and Afrotropical regions, can be differentiated into multiple groups of species that harbor high levels of hidden diversity. In this work, theserrulatusspecies group ofMerodonis revised, providing an illustrated key to species, a detailed discussion on the taxonomic characters and a morphological diagnosis, including also the first data about the preimaginal morphology of this species group. The study includes characteristics of the 13 species of theM. serrulatusgroup, along with the available distributional data. Moreover, descriptions are provided for seven new species, namelyM. defectusVujić, Likov & Radenkovićsp. nov.,M. disjunctusVujić, Likov & Radenkovićsp. nov.,M. mediumVujić, Likov & Radenkovićsp. nov.,M. nigrocapillatusVujić, Likov & Radenkovićsp. nov.,M. nigropunctumVujić, Likov & Radenkovićsp. nov.,M. opacusVujić, Likov & Radenkovićsp. nov., andM. trianguloculusVujić, Likov & Radenkovićsp. nov.In addition, the taxaM. serrulatus(Wiedemann in Meigen, 1822),M. bequaertiHurkmans, 1993,M. hirsutusSack, 1913,M. kawamuraeMatsumura, 1916,M. sacki(Paramonov, 1936) andM. sophronHurkmans, 1993 are redefined and redescribed. Following a detailed study of the type material sourced from different entomological collections, the status of all available taxa related toM. serrulatusis revised and a new synonymy is proposed:M. tenerSack, 1913syn. nov.(junior synonym ofM. serrulatus). The identity ofM. trizonus(Szilády, 1940) could not be assessed as the type specimens are lost. Thus, the nameM. trizonusis considered asnomen dubium. The monophyly and composition of this species group are assessed through Maximum Parsimony and Maximum Likelihood analyses of the mitochondrial COI and nuclear 28S rRNA gene sequences.

International audience; The mosquito family (Diptera: Culicidae) constitutes the most medically important group of arthropods because certain species are vectors of human pathogens. In some parts of the world, the diversity is so high that the accurate delimitation and/or identification of species is challenging. A DNA-based identification system for all animals has been proposed, the so-called DNA barcoding approach. In this study, our objectives were (i) to establish DNA bar-code libraries for the mosquitoes of French Guiana based on the COI and the 16S markers, (ii) to compare distance-based and tree-based methods of species delimitation to traditional taxonomy, and (iii) to evaluate the accuracy of each marker in identifying specimens. A total of 266 specimens belonging to 75 morphologically identified species or morphospecies were analyzed allowing us to delimit 86 DNA clusters with only 21 of them already present in the BOLD database. We thus provide a substantial contribution to the global mosquito bar-coding initiative. Our results confirm that DNA barcodes can be successfully used to delimit and identify mosquito species with only a few cases where the marker could not distinguish closely related species. Our results also validate the presence of new species identified based on morphology, plus potential cases of cryptic species. We found that both COI and 16S markers performed very well, with successful identifications at the species level of up to 98% for COI and 97% for 16S when compared to traditional taxonomy. This shows great potential for the use of metabarcoding for vector monitoring and eco-epidemiological studies.

Understanding the genomic basis of evolutionary adaptation requires insight into the molecular basis underlying phenotypic variation. However, even changes in molecular pathways associated with extreme variation, gains and losses of specific phenotypes, remain largely uncharacterized. Here, we investigate the large interspecific differences in the ability to survive infection by parasitoids across 11 Drosophila species and identify genomic changes associated with gains and losses of parasitoid resistance. We show that a cellular immune defense, encapsulation, and the production of a specialized blood cell, lamellocytes, are restricted to a sublineage of Drosophila, but that encapsulation is absent in one species of this sublineage, Drosophila sechellia. Our comparative analyses of hemopoiesis pathway genes and of genes differentially expressed during the encapsulation response revealed that hemopoiesis-associated genes are highly conserved and present in all species independently of their resistance. In contrast, 11 genes that are differentially expressed during the response to parasitoids are novel genes, specific to the Drosophila sublineage capable of lamellocyte-mediated encapsulation. These novel genes, which are predominantly expressed in hemocytes, arose via duplications, whereby five of them also showed signatures of positive selection, as expected if they were recruited for new functions. Three of these novel genes further showed large-scale and presumably loss-of-function sequence changes in D. sechellia, consistent with the loss of resistance in this species. In combination, these convergent lines of evidence suggest that co-option of duplicated genes in existing pathways and subsequent neofunctionalization are likely to have contributed to the evolution of the lamellocyte-mediated encapsulation in Drosophila.

International audience; Trollius europaeus (Ranunculaceae) is involved in an intimate interaction with several species of Chiastocheta flies (Anthamyiidae) that are both seed predators and pollinators. In this paper, we analyse the oviposition strategy of the six Chiastocheta species found to coexist on T. europaeus in 19 populations from the French Alps. We shaw that the species are not equivalent in their oviposition behaviour:, C. rotundiventris usually deposits no more:than one egg per flower in first-day flowers whereas C. dentifera aggregates ifs eggs on fruits and thus does not contribute to pollination at all; the four remaining species deposit eggs sequentially during the flowering period from the 2nd to the :7th day. Hence, the outcomes of the interaction in terms of net Seed production for the plant greatly depend on the Chiastocheta species visiting it,ranging from a mutualistic to a purely-parasitic interaction. We assessed mitochondrial divergence between Chiastocheta spp: by sequencing a 1320-bp mitochondrial DNA fragment. The low divergence observed between species (0-4-15%) suggests that genus diversification took place recently. Unlike in other plant-insect systems where diversification is usually thought to be driven by cospeciation or host shifts we propose that Chiastocheta speciation took place within the host plant. Basal separation of a particularly mutualistic species provided favourable conditions far plant specialization on this seed-parasite as: a pollinator early in the evolution of the association. The parasitic species ovipositing on fruits derived from a species ovipositing on flowers. Diversification of the intermediate strategies probably occurred in relation with the Pleistocene climatic events, reproductive isolation between species being reinforced by niche partitioning for oviposition and/or sexual selection.

In this study, we examined the morphology, genetics and distribution of the members of the Merodon chalybeus subgroup (M. aureus species group): M. chalybeus Wiedemann in Meigen, 1822, M. minutusStrobl, 1893 and M. robustusVeselić, Vujić & Radenković, 2017. Two of the species, M. chalybeus and M. minutus, are morphologically very similar and often misidentified in the literature. Here, by employing an integrative taxonomic approach we provide strong evidence for the separation of M. chalybeus and M. minutus. Our results show their clear allopatric distribution: M. minutus on the Balkan Peninsula, Sicily, Sardinia and Corsica, while M. chalybeus is a western Mediterranean species distributed on the Iberian Peninsula and northwest Africa. Data on the distribution of M. robustus were updated, with new records from Cyprus, Israel and Turkey, besides its type locality (Samos in Greece). We provide evidence for M. chalybeus and M. minutus representing a species complex, named the M. chalybeus complex, which together with M. robustus constitute the M. chalybeus subgroup. © 2021 Finnish Zoological and Botanical Publishing Board.