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The Afrotropical representatives of the hoverfly genus Phytomia Guérin-Méneville (Diptera) are revised. In total, 19 species are recognized of which three are new to science: Phytomia austeni sp. nov., P. memnon sp. nov., and P. pallida sp. nov. Phytomia neavei Bezzi is considered a junior synonym of P. kroeberi (Bezzi), P. noctilio Speiser a junior synonym of P. pubipennis Bezzi, and P. ephippium Bezzi a junior synonym of P. melas (Bezzi). Lectotypes are designated for the following species: Megaspis bulligera Austen, Megaspis erratica Bezzi, and Megaspis poensis Bezzi. In addition, unpublished lectotype designations are hereby formally published for the following species: Megaspis bullata Loew, Megaspis curta Loew, and Megaspis capito Loew. Phytomia curta (Loew) is considered a valid species, and differentiated from P. natalensis (Macquart). Phytomia fronto Loew is tentatively considered to belong to the genus Simoides Loew. The relationship between the different Phytomia species, as well as the relationship between Phytomia and Simoides, is briefly discussed based on morphological and DNA data.

Recently (2013-2014), several hoverfly specimens from two localities in Benin and Cameroon (West and Central Africa) were caught from a species that we could not identify using existing identification keys for Afrotropical Syrphidae. Specific identification as Toxomerus floralis (Fabricius) was accomplished using morphology and various Neotropical identification keys. Corroboration of this identification was made by sequencing of the standard COI barcode region and a subsequent BLAST-IDS in BOLD that revealed a 100% sequence similarity with Toxomerus floralis from Suriname (South America). Species identification was further supported by sequencing parts of the nuclear 18S and 28S rRNA genes. The species is widespread in Togo, Benin, Nigeria and Cameroon, and eggs, larvae and adults are abundant at several localities. Yet, the full extent of its geographic distribution within tropical Africa remains to be determined. This is only the second known established introduction of a non-African hoverfly species in the Afrotropics. Interestingly, the larvae of the species have been reported as predators of Aphididae and Delphacidae but we found them to be pollenivorous, which is a rare feeding mode within the subfamily Syrphinae. Moreover, it is the only known Syrphinae species of which the larvae feed on pollen from two plant species from different families (Cyperaceae and Orobranchaceae). This example illustrates how DNA barcoding may allow a fast and accurate identification of introduced species.

The identification of Afrotropical hoverflies is very difficult because of limited recent taxonomic revisions and the lack of comprehensive identification keys. In order to assist in their identification, and to improve the taxonomy of this group, we constructed a reference dataset of 513 COI barcodes of 90 of the more common nominal species from Ghana, Togo, Benin and Nigeria (W Africa) and added ten publically available COI barcodes from nine nominal Afrotropical species to this (total: 523 COI barcodes; 98 nominal species; 26 genera). The identification accuracy of this dataset was evaluated with three methods (K2P distance-based, Neighbor-Joining (NJ) / Maximum Likelihood (ML) analysis, and using SpeciesIdentifier). Results of the three methods were highly congruent and showed a high identification success. Nine species pairs showed a low (< 0.03) mean interspecific K2P distance that resulted in several incorrect identifications. A high (> 0.03) maximum intraspecific K2P distance was observed in eight species and barcodes of these species not always formed single clusters in the NJ / ML analayses which may indicate the occurrence of cryptic species. Optimal K2P thresholds to differentiate intra- from interspecific K2P divergence were highly different among the three subfamilies (Eristalinae: 0.037, Syrphinae: 0.06, Microdontinae: 0.007-0.02), and among the different general suggesting that optimal thresholds are better defined at the genus level. In addition to providing an alternative identification tool, our study indicates that DNA barcoding improves the taxonomy of Afrotropical hoverflies by selecting (groups of) taxa that deserve further taxonomic study, and by attributing the unknown sex to species for which only one of the sexes is known.

We examined the phylogeny and intrageneric classification of eristaline hoverfly genera from the Afrotropical Region using mitochondrial genomes. Genome skimming was used to obtain (nearly) full mtDNA and nuclear rDNA (18S, 28S) genomes of 120 museum vouchers from eight genera and 98 species. Phylogenetic reconstructions of mitogenomes and mitogenomes + nuclear rDNA yielded comparable phylogenies while that of rDNA only resulted in poorly resolved phylogenies. Phylogenetic analyses focused on six genera and supported the monophyly of the genera Chasmomma Bezzi, Eristalinus Rondani, Mesembrius Rondani and Syritta Le Peletier & Serville, whereas Simoides Loew was not monophyletic and rendered PhytomiaGuérin‐Méneville paraphyletic. We therefore synonymize Simoides with Phytomia. Within Chasmomma, two species‐groups that differ in the colour and the shape of the hind femora (Chasmomma femoratum and Chasmomma nigrum species‐groups) were supported. Within Eristalinus, the monophyly of the subgenera Merodonoides Curran and Eristalodes Mik was supported, but not of the subgenus Eristalinus Rondani. Within Syritta, the monophyly of three out of the five species‐groups tested was rejected. This approach illustrates the importance of integrative and iterative approaches in taxonomy and shows that genomic data may not only clarify the systematic relationships among hoverfly genera and species, but also offer perspectives into the evolution of morphological and ecological variation within the family. [ABSTRACT FROM AUTHOR]

The Afrotropical representatives of the hover fly genus Mesembrius Rondani, 1857 (Diptera) are divided into two subgenera, namely Mesembrius s.s. and Vadonimyia Séguy, 1951 and, in this present work, the subgenus Mesembrius s.s. is revised. A total of 23 Mesembrius s.s. species are recognised for the Afrotropics. Known species are re-described and six species new to science are described: Mesembrius arcuatus sp. nov., M. copelandi sp. nov., M. longipilosus sp. nov., M. sulcus sp. nov., M. tibialis sp. nov. and M. vockerothi sp. nov. Mesembrius africanus (Verrall, 1898) is considered a junior synonym of M. senegalensis (Macquart, 1842), M. ctenifer Hull, 1941 a junior synonym of M. caffer (Loew, 1858), M. lagopus (Loew, 1869) a junior synonym of M. capensis (Macquart, 1842) and M. platytarsis Curran, 1929 a junior synonym of M. simplicipes Curran, 1929. The females of Mesembrius chapini Curran, 1939, M. rex Curran, 1927 and M. regulus (Hull, 1937) are described for the first time. Lectotypes are designated for Mesembrius caffer, M. capensis, M. cyanipennis (Bezzi, 1915), M. minor (Bezzi, 1915), M. senegalensis, M. strigilatus (Bezzi, 1912) and M. tarsatus (Bigot, 1883). Separate identification keys for males and females are presented. We obtained 236 DNA barcodes for 18 species. The relationships amongst the different Mesembrius species are briefly discussed, based on morphological and DNA barcode data. [ABSTRACT FROM AUTHOR]

The representatives of the Afrotropical hover fly genus Senaspis Macquart (Diptera) are revised. In total, ten species are recognized. Senaspis apophysata (Bezzi) is herewith placed as junior synonym of S. flaviceps Macquart, S. livida (Bezzi) is herewith placed as junior synonym of S. dentipes (Macquart) and S. griseifacies (Bezzi) is herewith placed as junior synonym of S. haemorrhoa (Gerstaecker). All species are redescribed and an identification key is provided. DNA barcoding analysis (7 species, 64 barcodes) showed that the technique can be used to unambiguously identify the species. The relationships among the different Senaspis species are discussed based on morphological and DNA data. [ABSTRACT FROM AUTHOR]

In 2003, the invasive fruit fly Bactrocera invadens Drew, Tsuruta & White (Diptera: Tephritidae) (Drew et al. 2005), of possible Sri Lankan origin, has been detected in the East and about 1 yr later in West Africa. In regular surveys in Benin and Cameroon covering 4 yr, samples from 117 plant species across 43 families have been obtained. Incubation of field-collected fruits demonstrate that in West and Central Africa (WCA) B. invadens is highly polyphagous, infesting wild and cultivated fruits of at least 46 species from 23 plant families with guava (Psidium spp.), mango (Mangifera spp.), and citrus (spp.), and the wild hosts tropical almond (Terminalia catappa L.), African wild mango (Irvingia gabonensis (Aubry-Lecomte) Baill.), and sheanut (Vitellariaparadoxa C.F.Gaertn.) showing the highest infestation index. B. invadens occurs in 22 countries of WCA with new records for Angola, Central African Republic, the Congo, DR Congo, Equatorial Guinea, Gabon, Gambia, Guinea Bissau, Mali, Mauritania, Niger, and Sierra Leone. Overall, the pest has spread across a North-South distance of ≈-5,000 km representing a contiguous area of >8.3 million km² within WCA. B. invadens has adapted to a wide range of ecological and climatic conditions extending from low land rainforest to dry savanna. Because of its highly destructive and invasive potential, B. invadens poses a serious threat to horticulture in Africa if left uncontrolled. Moreover, the presence of this quarantine pest causes considerable restrictions on international trade of affected crops. [ABSTRACT FROM AUTHOR]

Despite their significant impact on human life in the Afrotropical Region, Diptera remain understudied. For a large part this is due to a lack of Diptera taxonomic experts and collection curators from the Afrotropical Region (except for South Africa perhaps), the difficulties some developing countries face in maintaining collections, and the low number of digitised specimens. This impedes the use of these Diptera collections for identification services, taxonomic and phylogenetic research, and other biological research areas. The dire need for knowledge transfer and training of young and emerging entomologists in the Afrotropical Region has prompted the Royal Museum for Central Africa and collaborating institutes to organise entomological training courses in the Afrotropical Region. The training courses take place in Africa, in strategic locations, cover a period of ten working days, are taught in English, and are free of cost to participants and lecturers. Here, we first provide a brief history of the evolution of the training courses. Second, we give a short description of the gender, age, educational and professional profile of the applicants and participants of the training courses. Third, we provide as much information as possible on all aspects of the organisation of the training courses. All information is freely available and documents are provided in Word or Excel format to facilitate future use by others. It is to be hoped that this information shall stimulate and facilitate the organisation of other entomological (or similar) training courses in the Afrotropical Region and other biogeographical regions. Such training courses will stimulate South-South networks for entomology research and the simultaneous training of participants with a different educational or professional background might foster collaborations between universities, other scientific institutes in postgraduate training and research. They may also initiate collaboration between scientific institutes and those involved in management, policy making, outreach, or implementation of legal procedures. We believe that this kind of training courses presents a best way forward in the organisation of similar capacity building activities that will contribute to a sustainable network of entomologists. Finally, these training courses may be one of the many possible ways to reduce the gender inequality gap in biological sciences in the Afrotropical Region. [ABSTRACT FROM AUTHOR]