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Hydaticus dhofarensis Pederzani, 2003, the only endemic diving beetle known from Dhofar Region is newly recorded from Masirah Island, central Oman. Analysis of 3ʹ region of the mitochondrial cytoch...

Cydistinae are a rare monogeneric beetle lineage from Asia with a convoluted history of classification, historically placed in various groups within the series Elateriformia. However, their position has never been rigorously tested. To resolve this long-standing puzzle, we are the first to present sequences of two nuclear and two mitochondrial markers for four species of Cydistinae to determine their phylogenetic position. We included these sequences in two rounds of analyses: one including a broad Elateriformia dataset to test placement at the superfamily/family level, and a second, including a richer, targeted sampling of presumed close relatives. Our results strongly support Cydistinae as sister to Phengodidae in a clade with Rhagophthalmidae. Based on our molecular phylogenetic results and examination of morphological characters, we hereby transfer the formerly unplaced Cydistinae into Phengodidae and provide diagnoses for the newly circumscribed Phengodidae, Cydistinae and Cydistus. Since both Phengodidae and Rhagophthalmidae have bioluminescent larvae and strongly neotenic females, similar features can be hypothesized for Cydistinae. Additionally, Cydistus minor is transferred to the new genus Microcydistus.

The available data on the biology of the water scavenger beetle genus Protosternum Sharp, 1890 (Hydrophilidae: Sphaeridiinae: Protosternini) are summarized, indicating an obligate association of Protosternum beetles with banana plants (Musaceae): they inhabit decaying tissues of old banana stems in which adult feeding, larval development and pupation takes place. Second and third instar larvae and pupa of the Taiwanese-endemic P. abnormale (Orchymont, 1913) are described in detail, based on field-collected specimens associated with co-occurring adults by cox1 DNA barcodes. Larvae are unique in the Hydrophiloidea by having strongly asymmetrical mouthparts with a large basal bifid tooth on the right mandible, indicating a specialized prey preference. Putative larval synapomorphies of the Protosternini are revealed, based on the comparison of the Protosternum larva with that of Sphaerocetum. Taxonomic status of P. abnormale is revealed to be confused by previous authors due to the absence of male specimens and is clarified here. Two new species are described based on specimens previously misidentified as P. abnormale: P. malayanum sp. nov. from Sumatra and Peninsular Malaysia, and P. hainanense sp. nov. from Hainan.

Entomological collections are the target of various insect pests, e.g. carpet beetles (Dermestidae) and booklice (Psocoptera) which can damage and completely destroy dry specimens in a relatively short time. Collections in the National Museum, Czech Republic (NMP) including the entomological ones are protected by fumigation using commercially available smoke shells ‘Cytrol Super SG’; fumigation is performed twice a year. The active insecticidal substance of these smoke shells is cypermethrin (6.25%). We tested whether the repeated cypermethrin fumigation of the NMP entomological collections negatively affects the quality of mitochondrial DNA in dry specimens and prevents the subsequent use of these samples for molecular analyses required for identification, taxonomy, systematics, and phylogenetic studies. We used 32 freshly fixed specimens of the flower chafer Oxythyrea funesta (Poda von Neuhaus, 1761) and 32 freshly fixed specimens of the brown-tailed cockroach Supella longipalpa (Fabricius, 1798). One half of specimens of both species was stored outside NMP and not fumigated (negative control), and the other half was deposited in collection hall with the NMP insect collection and directly exposed to the fumigation. Subsequently, all specimens were processed in a molecular laboratory under a standardized protocol using one leg as the source tissue after each fumigation, and the 658 bp long barcoding region of the cytochrome oxidase I (cox1) as the testing gene fragment. Results of the PCR product electrophoresis and the sequences acquired confirmed that the repeated fumigation had no negative effect on tested samples.

Seidel, Matthias, Arriaga-Varela, Emmanuel, Vondráček, Dominik (2019): Abstracts of the Immature Beetles Meeting 2019 October 3-4, Prague, Czech Republic. Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 59 (2): 569-582, DOI: 10.2478/aemnp-2019-0050, URL: http://dx.doi.org/10.2478/aemnp-2019-0050

Senodoniini is a small lineage of click beetles currently comprising 21 species in two genera, distributed in the Himalayas and East and Southeast Asia. The definition and limits of this group have changed considerably during its history. Recent authors treat Senodoniini as a tribe within Dendrometrinae, usually close to Dimini, but this placement has never been rigorously tested. Here, we shed new light on the systematic position and limits of Senodoniini by performing a combined phylogenetic analysis of two nuclear and two mitochondrial molecular markers. Our results recovered Senodoniini not monophyletic, and placed them into the Lissominae complex, where they formed a clade with Austrelater Calder &amp, Lawrence (Protelaterini). Molecular phylogeny is in agreement with the adult morphology. Additionally, we examined the morphology of a monotypic genus Rostricephalus Fleutiaux from Southeast Asia, which was previously classified in various Elateridae groups including Senodoniini, and its position was always uncertain. This genus shares morphological characters with Protelaterini. We provide morphological redescriptions as well as the figures of main diagnostic characters for Senodonia Laporte, Sossor Cand&egrave, ze, and Rostricephalus. Based on our results, we place these genera to Lissominae: Protelaterini, and hence synonymize Senodoniini Schenkling with Protelaterini Schwarz.

Platynectes (Gueorguievtes) davidorum sp. nov. is described, including all larval instars, from hygropetric habitats in Fujian and Zhejiang provinces, eastern China. The new species can be easily distinguished from all other Asia Platynectes Régimbart, 1879 with dorsally strongly convex habitus, distinctly impressed double reticulation of elytra, short appendages and the shape of median lobe of aedeagus. Collected larvae were successfully associated with adults using a molecular approach and the barcode for the new species is provided as well as the phylogenetic position based on the mitochondrial cytochrome oxidase I gene; they are described and illustrated, with detailed morphometric and chaetotaxic analyses of the cephalic capsule, head appendages, legs, last abdominal segment, and urogomphi. The classification of the new species within the subgenus Gueorguievtes Vazirani, 1976, and its adaptation to hygropetric habitats are briefly discussed.

Platynectes ( Agametrus ) zoque sp. nov. is described from the state of Oaxaca, Mexico. It is externally similar to the only Central American Platynectes, P. nitens (Sharp) from Panama and Costa Rica, but can be recognized by the shape of the male genitalia. The genetic distance between both species is 6.8% in the cox1 gene fragment. The finding of Platynectes in Mexico extends the known distribution of the genus in the Americas by about 1,300 km to the northwest. Thirteen species of the subgenus Agametrus Sharp are currently known, occurring in the Cordilleras from Chile to Mexico. A list of all species is provided including 10 new combinations resulting from the phylogenetic analysis of Toussaint et al. (2017): Platynectes ( Agametrus ) boliviensis (Regimbart, 1899), P. (A.) humilis (Sharp, 1882), P. (A.) labratus (Sharp, 1882), P. (A.) nitens (Sharp, 1887), P. (A.) peruvianus (Laporte, 1835), P. (A.) rotundatus (Brinck, 1948) (all from Agametrus ); P. (A.) curtulus (Regimbart, 1899), P. (A.) darlingtoni (Gueorguiev, 1971), P. (A.) gaudichaudii (Laporte, 1835), and P. (A.) muelleri (Kirsch, 1865) (all from Leuronectes Sharp). Platynectes ( Gueorguievtes ) darlingtoni Gueorguiev, 1972, a junior homonym of P. (A.) darlingtoni (Gueorguiev, 1971), is replaced with its junior subjective synonym P. multimaculatus Watts, 1978.

Rapid and reliable identification of insects is important in many contexts, from the detection of disease vectors and invasive species to the sorting of material from biodiversity inventories. Because of the shortage of adequate expertise, there has long been an interest in developing automated systems for this task. Previous attempts have been based on laborious and complex handcrafted extraction of image features, but in recent years it has been shown that sophisticated convolutional neural networks (CNNs) can learn to extract relevant features automatically, without human intervention. Unfortunately, reaching expert-level accuracy in CNN identifications requires substantial computational power and huge training data sets, which are often not available for taxonomic tasks. This can be addressed using feature transfer: a CNN that has been pretrained on a generic image classification task is exposed to the taxonomic images of interest, and information about its perception of those images is used in training a simpler, dedicated identification system. Here, we develop an effective method of CNN feature transfer, which achieves expert-level accuracy in taxonomic identification of insects with training sets of 100 images or less per category, depending on the nature of data set. Specifically, we extract rich representations of intermediate to high-level image features from the CNN architecture VGG16 pretrained on the ImageNet data set. This information is submitted to a linear support vector machine classifier, which is trained on the target problem. We tested the performance of our approach on two types of challenging taxonomic tasks: 1) identifying insects to higher groups when they are likely to belong to subgroups that have not been seen previously and 2) identifying visually similar species that are difficult to separate even for experts. For the first task, our approach reached \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} }{}$CDATA[$CDATA[$>$$\end{document}92% accuracy on one data set (884 face images of 11 families of Diptera, all specimens representing unique species), and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} }{}$CDATA[$CDATA[$>$$\end{document}96% accuracy on another (2936 dorsal habitus images of 14 families of Coleoptera, over 90% of specimens belonging to unique species). For the second task, our approach outperformed a leading taxonomic expert on one data set (339 images of three species of the Coleoptera genus Oxythyrea; 97% accuracy), and both humans and traditional automated identification systems on another data set (3845 images of nine species of Plecoptera larvae; 98.6 % accuracy). Reanalyzing several biological image identification tasks studied in the recent literature, we show that our approach is broadly applicable and provides significant improvements over previous methods, whether based on dedicated CNNs, CNN feature transfer, or more traditional techniques. Thus, our method, which is easy to apply, can be highly successful in developing automated taxonomic identification systems even when training data sets are small and computational budgets limited. We conclude by briefly discussing some promising CNN-based research directions in morphological systematics opened up by the success of these techniques in providing accurate diagnostic tools.

The genus Oxythyrea Mulsant, 1842 comprises ten currently recognized species. So far, larval descriptions for only three species are available. Here, we present comprehensive descriptions of third instar larval morphology for the six previously unstudied Oxythyrea species along with detailed re-descriptions of larval morphology for the previously described species. All descriptions are supplemented by photographs and line art drawings of the morphological structures. This work also contains a key to third instar larvae of the genus Oxythyrea as well as observations from collecting sites with focus on biological characteristics of all covered species including pictures of biotopes and host plants for adults. In addition, notes on the breeding circumstances for species are provided.

Hlaváč, Peter, Vondráček, Dominik, Mohagan, Alma B. (2018): A new species of the genus Colilodion Besuchet, 1991 (Coleoptera: Staphylinidae: Pselaphinae) from Mindanao, the Philippines. Zootaxa 4370 (5): 562-568, DOI: https://doi.org/10.11646/zootaxa.4370.5.7

The development of modern methods of species delimitation, unified under the “integrated taxonomy” approach, allows a critical examination and re-evaluation of complex taxonomic groups. The rose chafer Protaetia (Potosia) cuprea is a highly polymorphic species group with a large distribution range. Despite its overall commonness, its taxonomy is unclear and subject to conflicting hypotheses, most of which largely fail to account for its evolutionary history. Based on the sequences of two mitochondrial markers from 65 individuals collected across the species range, and a detailed analysis of morphological characters including a geometric morphometry approach, we infer the evolutionary history and phylogeography of the P. cuprea species complex. Our results demonstrate the existence of three separate lineages in the Western Palearctic region, presumably with a species status. However, these lineages are in conflict with current taxonomic concepts. None of the 29 analyzed morphological characters commonly used in the taxonomy of this group proved to be unambiguously species- or subspecies- specific. The geometric morphometry analysis reveals a large overlap in the shape of the analyzed structures (pronotum, meso-metaventral projection, elytra and aedeagus), failing to identify either the genetically detected clades or the classical species entities. Our results question the monophyly of P. cuprea in regard to P. cuprina, as well as the species status of P. metallica. On the other hand, we found support for the species status of the Sicilian P. hypocrita. Collectively, our findings provide a new and original insight into the taxonomy and phylogeny of the P. cuprea species complex. At the same time, the results represent the first attempt to elucidate the phylogeography of these polymorphic beetles.

Anew hydrophilid genus Chimaerocyon gen. nov. containing two species, C. shimadai sp. nov. (Malaysia: Pahang) and C. sumatranus sp. nov. (Indonesia: Sumatra), is described. Specimens of C. shimadai were collected from brood cells in anest of Pheidole singaporensis Özdikmen, 2010. The biology of C. sumatranus remains unknown. A molecular phylogeny based on four genes (cox1, cox2, 18S and 28S) supports the placement of the genus as deeply nested within the Cercyon-group of the tribe Megasternini. This position is supported by the subdistal position of the median spur in the hind wing (unique to Megasternini) and the presence of sucking disc on male maxilla (unique for Megastemini+Sphaeridiini). The remaining external morphology differs substantially from other representatives of Megasternini. The hypothesis that the aberrant morphology of Chimaerocyon gen. nov. is a consequence of myrmecophily is discussed.

A new hydrophilid genus Chimaerocyon gen. nov. containing two species, C. shimadai sp. nov. (Malaysia: Pahang) and C. sumatranus sp. nov. (Indonesia: Sumatra), is described. Specimens of C. shimadai were collected from brood cells in a nest of Pheidole singaporensis Ozdikmen, 2010. The biology of C. sumatranus remains unknown. A molecular phylogeny based on four genes ( cox1 , cox2 , 18S and 28S ) supports the placement of the genus as deeply nested within the Cercyon -group of the tribe Megasternini. This position is supported by the subdistal position of the median spur in the hind wing (unique to Megasternini) and the presence of sucking disc on male maxilla (unique for Megasternini+Sphaeridiini). The remaining external morphology differs substantially from other representatives of Megasternini. The hypothesis that the aberrant morphology of Chimaerocyon gen. nov. is a consequence of myrmecophily is discussed.