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Rediscovery of a second species of Reed Beetle in Israel (Coleoptera, Chrysomelidae, Donaciinae)
No full textA species of reed beetle, Donacia simplex (Coleoptera, Chrysomelidae, Donaciinae) was recently rediscovered in northern Israel. Now a second species, Donacia tomentosa, has been rediscovered (verified using molecular analysis) living further south in Israel. In 2021 a reed beetle expert discovered a very old record of Donacia tomentosa from modern day Israel in the collections of the Natural History Museum (London) from a few specimens collected near Tel Aviv by the British in 1918 during WWI. In 2022 the authors discovered a viable population of D. tomentosa in Israel. Given the extensive amount of collecting by many good field entomologists in that region since 1918, it is surprising that this species had not been seen for 104 years. The location, biology, molecular analysis, and other details of this newly found viable population of D. tomentosa in Israel are provided here
A checklist of xyleborine ambrosia beetles (Coleoptera, Curculionidae, Scolytinae, Xyleborini) on a single fallen chinquapin tree (Castanopsis inermis) from Thailand: with a new species and a new country record
No full textThe tribe Xyleborini comprises over 1,300 species of ambrosia beetles, all of which form mutualistic relationships with fungi. Several beetle species exhibit strong host preferences, particularly within the plant family Fagaceae for genera such as Castanopsis. This study documents the xyleborine beetles associated with Castanopsis inermis in Thailand to improve understanding of their host use and diversity.Twenty species of xyleborine ambrosia beetles were collected from a single fallen Castanopsis inermis tree. Amongst them, twelve species were recorded from C. inermis for the first time. One species, Arixyleborus perbrevis Sittichaya & Smith, sp. nov., is described as new to science, while Cnestus ater (Eggers 1923) is newly recorded from Thailand. Some biological observations on xyleborine ambrosia beetles are also presented
Diversity of Niphargus (Crustacea, Amphipoda) in France, as revealed by DNA barcoding approach
No full textNiphargus is the most speciose amphipod genus inhabiting groundwater of the Western Palearctic. The genus is renowned for its notorious taxonomy, associated with large within- but often negligible between-species morphological variation. Results of molecular taxonomy suggested that morphological variation captured less than half of its species diversity, calling for a molecular revision of past taxonomic and faunistic works. Molecular assessment of species diversity within Niphargus has been conducted since the 2000s, but it remains spatially incomplete given the genus’ extensive geographic range. Here, we provide the first comprehensive assessment of the diversity of Niphargus in France using molecular markers. We sequenced the COI mitochondrial marker from 436 individuals collected from 234 locations. Using Assemble Species by Automated Partitioning, we identified 99 molecular operational taxonomic units (MOTU), among which 74 could represent potential new species. In turn, we selected one individual per MOTU, amplified nuclear markers 28S and Histone 3, aligned them with an additional 142 MOTUs from across the genus range, and reconstructed their phylogenetic relationships using the Maximum Likelihood method. We found that several nominal species occurring in France are polyphyletic. Furthermore, Niphargus from France comprised lineages derived from deep and terminal splits, some of which showed signs of evolutionary radiation. The phylogenetic relationships are consistent with the hypothesis that Niphargus originated in the western part of its range. This study addressed a knowledge gap in the molecular and spatial coverage of Niphargus, provided new barcodes for monitoring the diversity of the genus, and identified future directions for research
Taxonomic reassessment of “Podocnemis” argentinensis (Testudines, Pleurodira) from the Maíz Gordo Formation (late Paleocene) with a description of new specimens from the western flank of Sierra del Mal Paso, Province of Jujuy, Argentina
No full textWe reassess the taxonomy of the problematic taxon “Podocnemis” argentinensis from the Maíz Gordo Formation (late Paleocene) at Quebrada Queñoal (type locality), Departamento de Humahuaca, Jujuy province, Argentina. This plastron-based species was initially named as a member of the genus Podocnemis (Podocnemididae) based on the holotype and one referred specimen. Considering the dubious generic assignment of the holotype of “Podocnemis” argentinensis, we performed a thorough revision of the morphological characters of this taxon, based on the holotype and previously undescribed specimens from the same lithostratigraphic unit in the Casa Grande-Vizcarra river area (western flank of the Mal Paso Range, Tres Cruces Sub-basin) in Jujuy province, Argentina. The new referred specimens include a collection of shells found in association with one skull from Quebrada del Agujero, as well as some shells from Quebrada del Puesto in the same region. Comparison between the extended hypodigm of “Podocnemis” argentinensis and other podocnemidids suggests the assignment of this species to a new generic entity, based on the presence of a short preorbital skull portion with steeply curved prefrontal bones, both exoccipital bones with a dorso-medial process restricting the dorsal part of the foramen magnum to a narrow cleft, lateral orbits, absence of an interorbital groove, high maxillae, a large vomer and the generalized gular, extragular and humeral scute pattern. We included this species in a phylogenetic analysis to assess its relationships with other pelomedusoid turtles. It is recovered as the sister taxon of Gestemys powelli, with which it shares the following four synapomorphies: foramen posterius canalis carotici interni outside the basisphenoid, long basioccipital, reduced nuchal embayment and dorsoventral flattening of the shell. The clade including “Podocnemis” argentinensis and Gestemys constitutes a Paleogene Argentinean lineage which is more closely related to Erymnochelyinae and Peltocephalinae than to Podocnemidinae, a position supported by a more covered adductor fossa and a large anterior opening of the cavum pterygoidei
Ultrastructure of three species of Surirella (Bacillariophyta) from Lake Qinghai, China, with descriptions of two new species
No full textThree Surirella species found at the same locality in Lake Qinghai, northwestern China, are studied using light and scanning electron microscope observations. Two species are proposed as new to science and named S. ectorii sp. nov. and S. qinghainensis sp. nov. The third species is identified as S. brightwellii W. Smith. Both S. brightwellii and S. qinghainensis have valves with an ovate outline and a broadly rounded headpole and cuneate footpole, whereas S. ectorii has valves with a nearly elliptical outline and an almost isopolar headpole and footpole. Both S. ectorii and S. qinghainensis produce a marginal row of costae on the wall of the raphe canal, whereas S. brightwellii does not possess this feature. This study provides further insights into the diversity of endemic diatom species inhabiting the ancient Lake Qinghai and illustrates the variability of valve ultrastructure in the genus Surirella
Anti Money Laundering in Bitcoin Network Using Chaotic Time Series and Graph Convolution Network
No full textMoney laundering seriously threatens economic stability by legitimizing illegal gains. Despite the transparency and security advantages offered by the blockchain technology, anonymity can create a platform for concealing illegal activities. Therefore, detecting and preventing money laundering activities in blockchain networks are of great importance. This study classifies money transfers during Bitcoin transactions as licit or illicit. By working on the Elliptic dataset to detect money laundering activities in the Bitcoin network, we examined money laundering traffic data using a graph data structure. This study presents a novel method for analyzing complex networks in money laundering as a chaotic time series. First, we increase the number of features of the graph nodes and convert them into a time series. By transferring the obtained time series to the phase space, we calculated the Lyapunov Exponents and aimed to capture the changes and uncertainties in the dynamic structure of the system more accurately using different embedding dimensions. We reconstructed the graph structure representing the transactions based on the feature vectors of these exponents, and classified the transactions using the Graph Convolutional Network method. In our study, we achieved a precision of 92.5%, recall of 92.1%, F1-score of 92.3%, and accuracy of 86.2%. These results demonstrate the effectiveness and reliability of our model in detecting money laundering. This study offers a novel approach for classifying chaotic structures in anti money laundering
A taxonomic revision of Tragia (Euphorbiaceae) in Gabon, with a description of two threatened new species
No full textBackground and aims – The production of the Flora of Gabon is advancing biodiversity discovery and highlighting knowledge gaps in complex genera, such as Tragia. By studying this genus, we have identified new species to science and documented new country records for Gabon. Material and methods – Standard practices of herbarium taxonomy were applied to study material from institutions with important holdings from Central Africa. Key results – After a critical study of specimens from Gabon and surrounding territories, a total of six species of Tragia were identified in the country. Two new species, Tragia flagellata and T. sericea, are described and preliminarily assessed as Endangered (EN) and Vulnerable (VU), respectively. We cite Tragia mildbraediana and T. zenkeri as new records for Gabon. Comprehensive nomenclatural information is supplied and three lectotypes are designated. An updated identification key, an original illustration, photos of the new species, and maps are provided
Rapid prediction of green tea quality based on convolutional neural network
No full textThe appearance of tea is a core visual indicator of quality evaluation, which directly affects consumer perception and market grading. This study proposed a green tea appearance quality evaluation method based on a convolutional neural network. A green tea image dataset of three shapes was constructed, containing flat-shaped Dafo Longjing tea, sparrow tongue-shaped Huangshan Maofeng tea, and granular-shaped Pingshui Rizhu tea. Dafo Longjing tea and Huangshan Maofeng tea had six grades and Pingshui Rizhu tea had four grades. Approximately 1500 images were collected for each grade of tea samples, and 9608, 9312, and 5768 images were obtained for three kinds of teas, respectively. The AdamX optimizer, ExponentialLR learning rate decay and batch size 32 were used to compare the classification performance of the ResNet18 model and MobileNetV3 model. The results showed that ResNet18 model achieved 98.28%, 99.19%, and 99.74% accuracies in recognizing grade in Dafo Longjing, Huangshan Maofeng, and Pingshui Rizhu. And MobileNetV3 model achieved 98.91%, 99.62%, and 99.39%, respectively. The fluctuation trends of the precision and recall in the two models during grade identification were consistent, reaching more than 98.20% in ResNet18 model and more than 98.90% in MobileNetV3 model. The effect of parameter tuning on performance metrics was similar in three green teas, indicating that these two models were appropriate for usage in various shapes of green tea. The ResNet18 model with the ECA attention mechanism was larger than the MobileNetV3 model, so MobileNetV3 is more suitable for actual quality detection with its lightweight advantage. Both models confirm the effectiveness of deep learning in tea appearance quality evaluation and provide technical support for automated grading
Detecting technological progress in Russia: Intersectoral approach or the aggregate economy
No full textWe pioneer the estimation of technological progress parameters for Russia in the framework of the neoclassical theory. Implementing the CES production function (CES PF hereafter) as an instrument of output description, we construct a system of cointegrated time series which guarantee no spurious interpretations. Our analysis follows a logical transition from an aggregate to a sectoral level and is based on two convergent datasets of different length. For the aggregate economy most of our accepted models generally forecast a slight labor income share increase under capital-augmenting technical progress biased to labor. Selected models with structural break in 2008–2009 show below-unity elasticity of substitution between labor and capital. Sectoral estimates stand in support of labor income share (LS) growth across six of the eight analyzed economic sectors. We empirically illustrate the rule for LS direction in response to joint values of labor-to-capital elasticity of substitution and a combination of the relative factor intensity and the average growth rate of labor-to-capital ratio. The fact that the values of relative labor intensity in the Mining and Energy & Waste management sectors are less than the growth of labor-to-capital ratio provide no grounds for labor share rise. While our reduced-form evidence suggests that broad capital tax relaxations in these two sectors are unlikely to raise LS, this should be read as a hypothesis for future causal work rather than a policy prescription
Description of two new species of Psilochasmus Lühe, 1909 (Digenea, Psilostomidae), with remarks on the diversity of the genus and a key to its species
No full textPsilochasmus Lühe, 1909 is a small genus of psilostomid digeneans parasitic in birds and characterized by the presence of a retractable tail-like structure at the posterior end of the body. Despite its low diversity, the taxonomic history of the genus is tumultuous, with opinions varying from recognizing only a single species to 11 nominal species. In this study, newly generated and previously available sequences of nuclear ribosomal DNA operon (ITS1+5.8S+ITS2; 28S) and partial NADH dehydrogenase (nad1) mtDNA gene sequences of Psilochasmus spp. from Europe (Palearctic), North America (Nearctic) and South America (Neotropics) were used to assess the diversity of Psilochasmus spp. and explore the phylogenetic interrelationships among members of genus and to distinguish between species. Based on combined morphological and molecular data, descriptions of two new Psilochasmus species from Europe and North America, Psilochasmus slavaukrainii sp. nov. and Psilochasmus urbeni sp. nov., are provided, as well as the first morphological description of P. oxyurus specimens linked to DNA sequence data. In addition, a key to the identification of Psilochasmus spp. recognized as a result of this study has been constructed