Image-based recognition of parasitoid wasps using advanced neural networks.

Hymenoptera has some of the highest diversity and number of individuals among insects. Many of these species potentially play key roles as food sources, pest controllers and pollinators. However, little is known about the diversity and biology and ~80% of the species have not yet been described. Classical taxonomy based on morphology is a rather slow process but DNA barcoding has already brought considerable progress in identification. Innovative methods such as image-based identification and automation can further speed up the process. We present a proof of concept for image data recognition of a parasitic wasp family, the Diapriidae (Hymenoptera), obtained as part of the GBOL III project. These tiny (1.2-4.5mm) wasps were photographed and identified using DNA barcoding to provide a solid ground truth for training a neural network. Taxonomic identification was used down to the genus level. Subsequently, three different neural network architectures were trained, evaluated and optimised. As a result, 11 different genera of diaprids and one mixed group of 'other Hymenoptera' can be classified with an average accuracy of 96%. Additionally, the sex of the specimen can be classified automatically with an accuracy of >97%.

Review of German Spilomicrus Westwood (Hymenoptera, Diapriidae, Spilomicrini).

Background: This study provides an integrative taxonomy-based review for the genus Spilomicrus Westwood in Germany using DNA barcoding and classic morphology. New information: Spilomicrussimplex Tomsik, 1947 is placed in synonymy with S.antennatus Jurine, 1807; Spilomicrusthomsoni Kieffer, 1911 is removed from synonymy with S.hemipterus Marshall, 1868. A lectotype is designated for Spilomicrusnigripes Thomson, 1858. Newly recorded for Germany are the following species: S.thomsoni Kieffer, 1911, S.crassiclavis Marshall, 1868, S.lusitanicus Kieffer, 1910 and S.diversus Chemyreva, 2021. Three species, Spilomicrusbrevimalaris sp. nov., S.flavecorpus sp. nov. and S.politus sp. nov. are described as new to science. The 23 DNA-barcodes with species identification present a substantial addition over the previous German checklist. This study aims to update the number of nationwide known Spilomicrus species from fifteen to twenty. Furthermore, a new key to identify all European Spilomicrus species is provided.

Taxonomic and nomenclatural notes on Geodiaprialongiceps Kieffer, 1911 (Hymenoptera, Diapriidae) and synonymy of the genus Geodiapria Kieffer, 1910.

This paper reviews the status of Geodiapria and its nominotypical and only included species G.longiceps. Geodiapria was previously understood to be very similar to, and doubtfully separated from the genus Basalys. We use integrative taxonomy (morphology, DNA-barcoding, phylogenetic tree building) to show that the valid name for what was G.longiceps Kieffer, 1911 is now Basalysrufocinctus (Kiefer, 1911) and that Geodiapria is consequently a junior synonym of Basalyssyn. nov. The following taxa are new synonyms of B.rufocinctus: Loxotropalongiceps Wasmann, 1909, syn. nov., G.longiceps Kieffer, 1911, syn. nov., L.rufosignata Kieffer, 1911, syn. nov. Basalysrufocinctus is newly reported from Corsica, Germany, Norway and Spain.

New species and records of Pseudochironomini Sæther, 1977 (Diptera, Chironomidae) from the Dominican Republic.

Background: Pseudochironomini is a relatively small and poorly-studied tribe of subfamily Chironominae (Diptera, Chironomidae). New information: Pseudochironomusruthae Andersen & Baranov sp. nov. is described and figured, based on a single male collected in a light trap at Matadero, Dominican Republic. The species can be separated from its congeners by the combination of the following characters: wing without dark bands, dorsocentrals in partly double row and apex of superior volsella rounded. The species is the first Pseudochironomus species to be formally recorded and described from the Caribbean. In addition, a new record of Manoapahayokeensis Jacobsen & Perry, 2002 from the Dominican Republic is given. One specimen was DNA-barcoded and the barcode is given.

A novel approach for reliable qualitative and quantitative prey spectra identification of carnivorous plants combining DNA metabarcoding and macro photography.

Prey spectra (the number and composition of captured arthropods) represent a crucial aspect of carnivorous plant ecology, yet remain poorly studied. Traditional morphology-based approaches for prey identification are time-intensive, require specialists with considerable knowledge of arthropod taxonomy, and are hampered by high numbers of unidentifiable (i.e., heavily digested) prey items. We examined prey spectra of three species of closely-related annual Drosera (Droseraceae, sundews) from tropical northern Australia using a novel DNA metabarcoding approach with in-situ macro photography as a plausibility control and to facilitate prey quantity estimations. This new method facilitated accurate analyses of carnivorous plant prey spectra (even of heavily digested prey lacking characteristic morphological features) at a taxonomic resolution and level of completeness far exceeding morphology-based methods and approaching the 100% mark at arthropod order level. Although the three studied species exhibited significant differences in detected prey spectra, little prey specialisation was observed and habitat or plant population density variations were likely the main drivers of prey spectra dissimilarity.

Peering into the Darkness: DNA Barcoding Reveals Surprisingly High Diversity of Unknown Species of Diptera (Insecta) in Germany.

Determining the size of the German insect fauna requires better knowledge of several megadiverse families of Diptera and Hymenoptera that are taxonomically challenging. This study takes the first step in assessing these "dark taxa" families and provides species estimates for four challenging groups of Diptera (Cecidomyiidae, Chironomidae, Phoridae, and Sciaridae). These estimates are based on more than 48,000 DNA barcodes (COI) from Diptera collected by Malaise traps that were deployed in southern Germany. We assessed the fraction of German species belonging to 11 fly families with well-studied taxonomy in these samples. The resultant ratios were then used to estimate the species richness of the four "dark taxa" families (DT families hereafter). Our results suggest a surprisingly high proportion of undetected biodiversity in a supposedly well-investigated country: at least 1800-2200 species await discovery in Germany in these four families. As this estimate is based on collections from one region of Germany, the species count will likely increase with expanded geographic sampling.