Explore the vast range of titles available.

Galerucinae and Alticinae are typical herbivorous pests that seriously harm the growth of crops, trees, fruits, vegetables, and grasses worldwide. Historically, Galerucinae and Alticinae were treated as distinct sister subfamilies within Chrysomelidae. However, recent molecular phylogenetics and morphological reassessments have challenged this dichotomy, revealing that the boundary between these lineages is phylogenetically ambiguous. This study provides a systematic multi-view fusion framework, termed MVBeetle, for the convenient identification of the two target subfamilies. To this end, a multi-view image dataset was constructed based on synchronized high-resolution dorsal, lateral, and ventral views. The dataset comprises a total of 43 chrysomelid species, including 23 species from Galerucinae and 20 species from Alticinae. Subsequently, four convolutional neural network backbones (ResNet18, ResNet50, VGG16, and MobileNetV2) were developed as the core of MVBeetle by integrating multi-view features of leaf beetles. The experimental results show that the accuracy of multi-view fusion improved by 2.48%–12.95% compared with baseline models across the four networks. The optimized MVBeetle architecture achieved a peak classification accuracy of 94.44% ± 0.41%. Furthermore, Grad-CAM interpretability analysis indicated that MVBeetle’s attention significantly focused on key morphological features of different subfamilies (Alticinae and Galerucinae). Among these, the activation regions for Alticinae are mainly concentrated on the jumping legs, while Galerucinae focuses on the antennae. Importantly, cross-subfamily misclassifications were nearly zero, demonstrating the model’s strong taxonomic reliability. This study not only provides a high-precision and convenient classification model for leaf beetles, but also provides insights into the evolutionary morphology of beetles.

Background/Objectives: Flea beetles (Coleoptera, Chrysomelidae: Alticinae) show extensive karyotypic diversity, yet cytogenetic and genomic data remain scarce for many taxa. Species of the genus Podagrica are characterized by unusually high chromosome numbers compared with the modal condition in Alticinae, suggesting a history of chromosomal fissions. This study aimed to characterize the karyotype and repetitive DNA composition of Podagrica fuscicornis, with special emphasis on the satellitome and its contribution to chromosome organization. Methods: Male specimens of P. fuscicornis collected in southern Spain were analyzed using conventional cytogenetic techniques, including Giemsa staining, DAPI staining, and C-banding. Fluorescence in situ hybridization was employed to map nucleolar organizer regions (NORs), telomeric repeats, and major satellite DNA (satDNA) families. The satellitome was characterized using Illumina short-read sequencing and analyzed with the RepeatExplorer2/TAREAN pipeline to identify satDNA families and estimate their genomic abundance and divergence. Results: The male karyotype of P. fuscicornis was 2n = 40 (38 + XY), with an Xyp sex chromosome system. Constitutive heterochromatin was mainly pericentromeric, and the Y chromosome was largely heterochromatic. NORs were located on a single autosomal pair, and the ancestral insect telomeric motif (TTAGG)n was detected at chromosome ends. The satellitome comprised at least 70 different satDNA families, representing 9.51% of the genome, some of them related to transposable elements. Ten of these 70 satDNAs are shared in other Alticinae species. The most abundant families were primarily localized in pericentromeric regions and showed differential distribution between autosomes and sex chromosomes. Conclusions: These results indicate that extensive chromosomal fissions and high satDNA dynamics could drive the high chromosome number and heterogeneous genome organization in P. fuscicornis, highlighting the role of repetitive DNA in karyotype evolution within Chrysomelidae.

Oulema duftschmidi (Redtenbacher, 1874), Phyllotreta astrachanica Lopatin, 1977, and Ph. procera (Redtenbacher, 1849) are recorded for the first time for Uzbekistan; Longitarsus stragulatus dichrous Khnzorian, 1962 is recorded for the first time for Tajikistan. The geographic distribution of Acolastus pallidus (Lopatin, 1956) and Aphilenia ornata Reitter, 1889 is clarified. For all the taxa considered, images of the adult habitus and male genitalia (for some of them) are given.

The beetles of the subtribe Oedionychina (Chrysomelidae, Alticinae) are the only ones that have the atypical giant and achiasmatic sex chromosomes, which are substantially larger than the autosomes. Previous cytogenetic analyses suggest a large accumulation of repetitive DNA in the sex chromosomes. In this study, we examined the similarity of X and Y chromosomes in four Omophoita species and compared genomic differentiation to better understand the evolutionary process and the giant sex chromosomes origin. Intraspecific genomic comparation using male and female genomes of O. octoguttata and interespecific analyses using genomic DNA of O. octoguttata, O. sexnotata, O. magniguttis, and O. personata were performed. In addition, whole chromosome painting (WCP) experiments were performed with X and Y chromosome probes of O. octogutatta. CGH analysis revealed great genomic similarity between the sexes and a sex-specific region on the Y chromosome, and interspecific analysis revealed a genomic divergence between species. In contrast, WCP results revealed that the sex chromosomes of O. octoguttata have high intra- and interspecific similarity with the studied species. Our data support a common origin under the canonical evolution of the sex chromosomes in this group, as they have high genomic similarity between them.

Complex morphological or functional traits are frequently considered evolutionarily unique and hence useful for taxonomic classification. Flea beetles (Alticinae) are characterized by an extraordinary jumping apparatus in the usually greatly expanded femur of their hind legs that separates them from the related Galerucinae. Here, we examine the evolution of this trait using phylogenetic analysis and a time-calibrated tree from mitochondrial (rrnL and cox1) and nuclear (small subunits and large subunits) genes, as well as morphometrics of femora using elliptic Fourier analysis. The phylogeny strongly supports multiple independent origins of the metafemoral spring and therefore rejects the monophyly of Alticinae, as defined by this trait. Geometric outline analysis of femora shows the great plasticity of this structure and its correlation with the type and diversity of the metafemoral springs. The recognition of convergence in jumping apparatus now resolves the long-standing difficulties of Galerucinae–Alticinae classification, and cautions against the value of trait complexity as a measure of taxonomic significance. The lineage also shows accelerated species diversification rates relative to other leaf beetles, which may be promoted by the same ecological factors that also favour the repeated evolution of jumping as an anti-predation mechanism.

Epitrix species (Coleoptera: Chrysomelidae) feed mostly on plants from the family Solanaceae and some of them are major pests of potato crops. All Epitrix species are morphologically highly similar, which makes them difficult to identify and limits their study and management. Identification of species is mostly based on the observation of the genitalia and requires a high level of expertise. Here, we propose a tool to reliably identify all developmental stages of the most economically important Epitrix species feeding on potato in Europe and North America (Epitrix cucumeris, Epitrix similaris, Epitrix tuberis, Epitrix subcrinita and Epitrix hirtipennis). We first sequenced two DNA markers (mitochondrial cytochrome c oxidase I (COI) and nuclear internal transcribed spacer 2 (ITS2)) to test their effectiveness in differentiating among six Epitrix species (126 specimens). Morphospecies of Epitrix were well-differentiated by both DNA barcodes and no mitochondrial introgression was detected. Then, we developed an RFLP-based diagnostic method and showed that unambiguous species discrimination can be achieved by using the sole restriction enzyme TaqI on COI polymerase chain reaction products. The tool proposed here should improve our knowledge about Epitrix species biology, distribution and host range, three capacities that are particularly important in the detection and management of these pest species. Specifically, this tool should help prevent the introduction of E. tuberis and E. subcrinita in Europe and limit the spread of the recently introduced E. cucumeris and E. similaris, with minimal disruption to Solanaceae trade.

The rose flea beetle, RFB (Luperomorpha xanthodera Fairmaire 1888) is a new flower pest in Europe. In 2012, it was brought accidentally to central Poland. To search for this introduced species in the area adjacent to the site of the first finding, 29 plant species belonging to five botanical families (Lamiaceae, Brassicaceae, Asteraceae, Plantaginaceae, Crassulaceae) were monitored over a 3-year-long study (2016−2018). RFB were found on 11 herbaceous/ ornamental plant species (Lamiaceae, Brassicaceae, Asteraceae) along with feeding damage to the flowers. White mustard (Sinapis alba L., Brassicaceae), hyssop (L.), and Monarda spp. (Lamiaceae) were its most preferred host plants. In each season, RFB females preferred host plants which bloomed abundantly and vividly. However, among the examined plant species there was a large variation in the year-to-year RFB abundance. Over the examined period the RFB extended its abundance exponentially, and its population survived and established itself in the area. The general sex ratio of the beetles was strongly female biased. In the female pool, females with conspicuously swollen abdomens predominated. The results of our study provide more insight into RFB behaviour, its establishment and spreading into new areas. To support the evidence for the RFB risk factor as an agricultural/ horticultural pest, further research should focus on the beetles’ biology, reproductive tactics, larval host plant preference, larva-inflicted damage and harmfulness, the impact of the RFB on the native fauna, as well as its further local and distant migration propensity. Presently our knowledge about these aspects is still fragmentary.

This paper consists of an up to date annotated catalogue of the Afrotropical genera of Alticinae (Chrysomelidae), with biogeographical notes on the flea beetle fauna occurring in Sub-Saharan Africa and Madagascar. The following new synonymies are proposed: Eugonotes Jacoby, 1897 (a subgenus of Sanckia Duvivier, 1891) = Brancucciella Medvedev, 1995 syn. n.; Amphimela Chapuis, 1875 = Dibolosoma Jacoby, 1897 syn. n.; Amphimela Chapuis, 1875 = Halticova Fairmaire, 1898 syn. n.; Podagrica Chevrolat, 1837 = Podagrixena Bechyné, 1968 syn. n.; Aphthona Chevrolat, 1837 = Pseudeugonotes Jacoby, 1899 syn. n.; Nisotra Baly, 1864 = Pseudonisotra Bechyné, 1968 syn. n. The following new combinations are proposed: Afrorestia sjostedti (Weise, 1910) comb. n. (from Crepidodera); Bechuana natalensis (Jacoby, 1906) comb. n. (from Ochrosis); Sesquiphaera natalensis (Jacoby, 1906) comb. n. (from Sphaeroderma). The genus Hildenbrandtina Weise, 1910 is trasferred from Galerucinae to Alticinae. New distributional data for many genera in the Afrotropical region is provided. [PUBLICATION ABSTRACT]

Three saponins and two sapogenins had differential effects on food consumption in five near-isogenic flea beetle lines, which differ in their ability to utilize a novel host plant, Barbarea vulgaris (Brassicaceae). The ability to live on this plant is controlled by major, dominant R-genes in the flea beetle, Phyllotreta nemorum (Coleoptera: Chrysomelidae: Alticinae). A susceptible genotype (rr) is unable to live on the plant, whereas resistant genotypes (RR and Rr) can utilize the novel host plant. Among compounds isolated from B. vulgaris , hederagenin cellobioside (hederagenin-3-O-(4-O-β-D-glucopyranosyl)-β-D-glucopyranoside) inhibited feeding, whereas the effect of oleanolic acid cellobioside was much weaker. The aglycones (sapogenins) were inactive. Although hederagenin cellobioside was active against all flea beetle lines, its effect on food consumption was much stronger on the susceptible genotype (rr) compared to the resistant genotype (Rr). Susceptible and resistant flea beetle genotypes were equally sensitive to a non-host saponin, α-hederin (hederagenin-3-O-(2-O-α-L-rhamnopyranosyl)-α-L-arabinopyranoside). These results suggest that R-alleles in flea beetles might be specific adaptations to defensive saponins in B. vulgaris . A possible mechanism of action of the R-alleles might be to encode for an enzyme (e.g. a glucosidase), which is able to cleave glycosidic bonds in hederagenin cellobioside, but not in α-hederin. The potential role of saponins as defensive compounds in B. vulgaris and as targets for counter-adaptations in flea beetles and other insects is discussed.

The entire pathway for synthesis of the tyrosine-derived cyanogenic glucoside dhurrin has been transferred from Sorghum bicolor to Arabidopsis thaliana. Here, we document that genetically engineered plants are able to synthesize and store large amounts of new natural products. The presence of dhurrin in the transgenic A. thaliana plants confers resistance to the flea beetle Phyllotreta nemorum, which is a natural pest of other members of the crucifer group, demonstrating the potential utility of cyanogenic glucosides in plant defense.