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Cystic echinococcosis, a neglected parasitic cyclo-zoonosis is endemic in the Indian subcontinent. The etiological agent for this potentially fatal disease is a cryptic species complex, Echinococcus granulosus sensu lato (s. l.). The present study aimed at evaluating the role of small ruminants in circulating various E. granulosus s. l. genotypes in north India. The cladistics, haplotype network and genetic structure analyses were performed on the E. granulosus s. l. isolates collected from the slaughtered small ruminants (n = 1049) of north India (Chandigarh, Himachal Pradesh and Haryana) along with GenBank-archived E. granulosus s. l. sequences (n = 20) of ruminant origin from the Indian subcontinent by targeting the mitochondrial nad5 gene. The NCBI BLASTn analysis revealed the presence of zoonotic genotypes G1, G3 (E. granulosus sensu stricto), G5 (E. ortleppi), and G6 (E. canadensis). Haplotype network analysis exhibited the presence of 14 haplotypes, where the haplotypes corresponding to E. granulosus sensu stricto (s. s.) species (genotypes G1 and G3) were arranged in a stellate conformation. High haplotype (0.837 ± 0.059, 0.836 ± 0.068 and 0.894 ± 0.078) and low nucleotide (0.0249 ± 0.0104, 0.0369 ± 0.0142 and 0.0036 ± 0.0008) diversities were recorded for the overall data set, as well as Indian and Pakistani E. granulosus s. l. populations, respectively. Based on the mitochondrial nad5 gene, the present study provided comprehensive insights into the cladistics and population structure of E. granulosus s. l. genotypes circulating in north India and highlighted the role of sheep/goat-dog cycle in the circulation of the zoonotic genotypes.

Historical biogeography faces a persistent conceptual and methodological dilemma concerning the nature of its central analytical units. Using the recent proposal by Schultz and Cracraft (Cladistics 40, 653) as a catalyst, this article critiques the argument that causal inference necessitates the replacement of areas of endemism with barriers, contending that such a forced dichotomy is both artificial and reductionist. It is postulated that modern methodological advances allow areas of endemism to be rigorously treated as dynamic and quantitatively testable hypotheses, thereby overcoming long-standing objections that classify them as mere descriptive constructs. Conversely, an exclusive focus on barriers fundamentally underestimates the multifactorial nature of diversification, neglecting the structural role of dispersal and the complex spatiotemporal dynamism of isolating forces. Effective inference in historical biogeography demands an explicitly pluralistic and process-agnostic perspective, recognizing areas and barriers as complementary, intersecting elements. This integrative approach is essential for accurately capturing the emergent complexity of biogeographic patterns, moving the discipline beyond the limitations of unifocal causal models.

The stalk-eyed flies (Diptera: Schizophora: Diopsidae) are a diverse clade of acalyptrate flies known for their remarkable eye stalks and intriguing courtship behaviours. Despite their striking appearance and significance as subjects for ecological and ethological studies, phylogenetic relationships within Diopsidae have not yet been comprehensively investigated, and the evolutionary history of the family remains inadequately resolved. We here present the first time-calibrated phylogenetic analysis of Diopsidae based on 17 genes (12S, 16S, 18S, 28S, and 13 mitochondrial protein-coding genes, 18 536 bp) from 48 taxa, including all extant subfamilies and ~76% extant genera of the family, thus clarifying a number of outstanding questions about intra-familial relationships and the evolutionary history of the stalk-eyed flies. Our results support the monophyly of Diopsidae and its three subfamilies; Centrioncinae is recovered as sister to the stalk-eyed lineage Sphyracephalinae + Diopsinae; the Teleopsis genus-group as well as several currently recognized genera are non-monophyletic and require further taxonomic review to better resolve their phylogenetic status. Molecular dating and biogeographic analyses indicate an African origin of the crown group of Diopsidae in the middle Eocene, ca. 45 Ma; its early diversification events might have been driven by climatic and ecosystem transformations during the middle Eocene to middle Miocene; available evidence suggests that factors shaping the current distribution of Diopsidae include colonization of Madagascar from Africa via the Mozambique Channel, out-of-Africa dispersals mediated by the Gomphotherium land bridge along with favourable environmental conditions, and colonization of North America via the Bering Land Bridge. This study provides a framework for future investigations into the evolutionary history of the stalk-eyed flies, as well as for ecological and morphological evolutionary research.

The seed is an essential stage in the life history of gymnospermous and angiospermous plants, facilitating both their survival and dispersal. We reappraise knowledge of the evolutionary history of the gymnospermous seed, from its origin in the late Devonian through to the well-known end-Permian extinctions - an interval encompassing the origins of most major lineages of seed-bearing plants. The framework for our broader discussions is a novel cladistic analysis of anatomically preserved Palaeozoic seeds, analysing 79 seed-species for 89 morphological characters in a matrix containing only 24% missing values. The resulting consensus tree is weakly but fully resolved and compatible with traditional division into three informal seed groups: paraphyletic lagenocarps, paraphyletic trigonocarps and monophyletic cardiocarps. Three seed-genera - Rhychosperma, Albertlongia and Muricosperma - are revealed as potential 'missing links' between groups, and modest re-circumscription of seed-genera is required. Although the value of single-organ phylogenies remains controversial, the present seed-tree topology receives general support from the dated sequence of first appearances of seed-species in the fossil record, and from the topologies of morphological cladistic studies that combined conceptually reconstructed fossil plants with primitive extant lineages, notably ginkgos and cycads. Branch lengths in the tree and phenetic distances in ordinations of the matrix indicate similar overall rates of character change through the Palaeozoic, rather than a fractal pattern reflecting progressively increasing constraint, although early changes in architectural and pollination-related characters gradually give way to greater experimentation with the internal layering and external topography of the testa. Our process-based evolutionary inferences are informed by extant gymnosperms, particularly Cycas and Ginkgo. The origin of the true seed is attributed primarily to (1) the complex biochemical signalling needed to allow the sperm to reach the archegonia through the megasporangium wall and (2) the localised apoptosis of the megasporangium hypothesised to have simultaneously allowed hollowing out of the nucellar apex to form a sophisticated pollen-receiving apparatus (the pollen chamber) and secretion of a pollination drop to capture air-borne (pre)pollen. Subsequent potential key innovations include transfer of function of both pollination-drop channelling and pollen chamber sealing from the nucellar salpinx to the integumentary micropyle, and introduction of a haustorial pollen tube to direct spermatozoa towards the archegonia. Assuming that the seed-plant megasporangium terminates an axis, synorganisation has played a key role in seed evolution, leaf-like lateral organs being repeatedly pulled towards the apex and incorporated into the terminal structure. Lateral webbing of integumentary lobes eventually almost fully enclosed the nucellus, while a similar synorganisation process affecting a lower set of vegetative organs formed a cupule as yet another protective layer surrounding one or more ovules. Our tree refutes viewing these evolutionary developmental trends as linear transition series. The earliest seeds were small but soon increased to reach the maximum size achievable by gymnosperms. Dehiscence and dormancy mechanisms were likely primitive at best, while increasingly complex layering and sculpting of the testa may have aided both abiotic and biotic dispersal. The end-Permian extinction of plants bearing lagenocarps and trigonocarps is attributed tentatively to one or more of several features of reproductive biology identified as being vulnerable to desiccation.

Therapsids are early-diverging synapsids that thrived during the Permian and Triassic periods, and ultimately gave rise to mammals. They include six major groups, which already exhibited considerable diversity at their first appearance in the fossil record. Their early to middle Permian origins remain poorly understood due to a scarcity of fossils with clear therapsid morphology in the early Permian and the presence of an interval of poor fossil preservation near the early to middle Permian boundary (Olson’s Gap). This limits our insight into the phylogenetic relationships among the main middle Permian groups. This study presents a novel approach to therapsid phylogeny, using probabilistic frameworks. In performing a phylogenetic analysis based exclusively on cranial characters, using both RevBayes and MrBayes, this study challenges understanding of the early diversification of Therapsida. We recover Neotherapsida, with Anomodontia branching as the sister taxon to Theriodontia. Biarmosuchia and Dinocephalia form a clade. The positions of taxa such as Sinophoneus and Biseridens are reconsidered. The application of Fossilized Birth-Death models suggests that while Therapsida originated in the early Permian, currently known therapsid groups diversified around 281 to 272 million years ago and subsequently underwent rapid radiation into five clades: Biarmosuchia, Dinocephalia, Anomodontia, Gorgonopsia, and Eutheriodontia.

Deciphering the evolutionary history of lineages shaped by rapid radiation, hybridization and incomplete lineage sorting (ILS) remains a major challenge in phylogenetics. Previous studies of Hesperocyparis (Cupressaceae) relied on limited markers and yielded inconsistent results. Here, we applied target enrichment sequencing across multiple individuals per species to generate comprehensive genomic datasets, including 2628 nuclear single-copy genes and nearly complete plastid genomes. We reconstructed robust phylogenies, assessed gene flow and reticulation and inferred the spatiotemporal and ecological niche evolution of Hesperocyparis. Our analyses resolved the genus into three clades-Macrocarpa, Arizonica and the basal H. bakeri-and strongly supported its monophyly within the HCX clade (Hesperocyparis, Callitropsis, Xanthocyparis). However, significant cytonuclear discordance was observed, reflecting the influence of ancient hybridization and ILS. Molecular dating placed the origin of Hesperocyparis in the late Eocene (~39.2 Ma), with most diversification occurring during the Oligocene and Miocene. Ancestral range and state reconstructions support a northwestern North American origin, followed by complex southward and eastward dispersal patterns likely driven by climatic shifts towards increased aridity. This study highlights the utility of genome-scale data in resolving complex evolutionary relationships and underscores hybridization, climate-driven dispersal and ecological adaptation as key drivers of diversification in Hesperocyparis.

Passive tectonic uplift of populations is being discussed in a growing number of studies from many regions around the world, usually for areas that have undergone dramatic uplift in fold mountains (orogens). It is also proposed in belts of uplift along the margins ("shoulders") of rifts, as in south-eastern Brazil, West Africa and the rift mountains of Central and East Africa. Many groups show signs of having been left stranded inland with the retreat of inland epicontinental seas in the Cretaceous, consistent with the long-term persistence and passive uplift of populations in situ. Passive uplift provides a mechanism in which groups are elevated and also a mode of speciation that can help explain the anomalous, high diversity of areas such as the Andes ("Humboldt's enigma"). We suggest that one focus of future research could be on the location of elevational anomalies in species distributions. Studying these will require good information on the three-dimensional distribution of species, and this is still lacking for most groups. If these data were available, it would be possible to use niche models to identify populations at anomalous elevations.

The thread-legged bug tribe Leistarchini (Hemiptera: Reduviidae: Emesinae) is a cosmopolitan and diverse group characterized by a highly disproportionate spatial distribution across zoogeographic regions. Due to a historical lack of phylogenetic focus, the internal relationships and evolutionary history of the tribe remain poorly understood. In this study, we provide the first robust phylogenetic framework for Leistarchini by integrating molecular data from mitochondrial genomes and nuclear rDNA (88 taxa, 19 937 bp) with universal single-copy orthologs (24 taxa, 667 loci). Our results support the monophyly of Leistarchini and identify five major clades, including a newly described genus Calliemesa gen. n. Our findings further reveal that the five most species-rich genera (Nesita, Orthunga, Pleias, Ploiaria and Tinna) are either paraphyletic or polyphyletic as currently circumscribed. Molecular dating and biogeographic reconstructions suggest a Southeast Asian origin for the Leistarchini crown group during the late Palaeocene (ca. 57 Ma). Early diversification appears to have been driven by Paleogene geological and climatic shifts in Southeast Asia, while multiple intercontinental dispersals since the middle Eocene into the Afrotropics, Madagascar and the New World shaped the current global distribution. Ancestral state reconstructions indicate that the Leistarchini ancestor possessed a well-developed posterior pronotal lobe and a three-segmented protarsus. Subsequent evolutionary trajectories involved four independent transitions toward a shortened posterior pronotal lobe, and four separate reductions in protarsal segmentation.

We present a morphology-based backbone phylogeny of Cerambycidae beetles inferred by parsimony analyses using 77 adult characters scored for 101 species. This phylogeny is largely consistent with recent phylogenomic studies regarding key placements (e.g., Parandrini stat. rev. within Prioninae, Necydalini stat. rev. within Lepturinae, the sister-group relationship of Cerambycinae with Prioninae (including Parandrini), the monophyly of Saperdini, the non-monophyly of some Lamiinae tribes), while differing primarily in the position of Lamiinae. By testing various character and taxon-sampling partitions we revealed that some of the most variable external characters and all genital characters (without exploring aedeagal internal sac) have low phylogenetic signal, but still the more inclusive analyses are the most robust. Across all our analyses, Cerambycidae s.l. are consistently recovered as monophyletic, with Disteniinae stat. rev., Vesperinae stat. rev., and Oxypeltinae stat. rev. placed inside or adjacent to the core Cerambycidae s.s. clade depending on character sampling. Our results highlight the strength of phylogenomics in providing a robust framework for higher-level relationships, but also emphasize that morphology-based analyses remain indispensable for identifying and interpreting the character systems that define those relationships. This study exemplifies complementarity of morphological and genomic evidence, while providing a broad morphology-based phylogenetic analysis of Cerambycidae.

The Hengduan Mountains (HDM), a biodiversity hotspot in Southwest China, harbour numerous endemic taxa whose diversification has been driven by the complex geological history of this region. This study investigates the diversification of the katydid genus Sichuana, endemic to the HDM, integrating mitochondrial genomics, morphology and biogeography. We sequenced complete mitochondrial genomes of all known geographic populations of Sichuana, revealing four major clades diverging during the Late Miocene (5.06-8.37 Ma). Orogeny-driven vicariance fragmented ancestral populations, while unstable barriers may facilitate mitochondrial introgression, as evidenced by paraphyletic lineages contrasting with distinct morphologies. We describe five new species (S. brevicerca sp. nov., S. fortidens sp. nov., S. qiuzhi sp. nov., S. luqiaoensis sp. nov. and S. pseudomagna sp. nov.) and two subspecies (S. pseudomagna pseudomagna subsp. nov. and S. pseudomagna borealis subsp. nov.), highlighting the taxonomic challenges posed by discordance between mitochondrial DNA-based phylogenies and morphological classifications. This study demonstrates that orogeny-driven vicariance dominates speciation in low-dispersal insects, but transient gene flow complicates species delimitation. Our findings advocate for integrative taxonomy in biodiversity hotspots and highlight the HDM as a model system for studying biogeographic complexity.

Numerous tools have been developed since the advent of phylogenetic methods to assess tree robustness. Identifying the degree of contradiction in a phylogenetic matrix, as well as the specific contribution of each taxon and character, is essential for estimating its reliability. In parsimony-based phylogenetic inferences, classically used by paleontologists, a phylogeny results from the interaction of all the characters used in the analysis. Consequently, the support initially provided by the characters in the matrix may differ from that after optimization in the final tree, severing the link between the phylogenetic content of the matrix and that of the final tree. Thus, all methods aimed at measuring support only do so indirectly and the impact of individual characters or taxa can only be assessed after the analysis. Three-taxon analysis (3ta) is a phylogenetic method that can circumvent these issues by precisely measuring the support of targeted characters and/or taxa directly from the phylogenetic matrix. In 3ta, characters are coded as trees and decomposed into three-taxon statements (3ts). The analysis searches for the largest set of non-contradicting 3ts to compute the optimal classification. Because the analysis is a compatibility procedure, not an optimization procedure, character supports on the tree are independent from one another. This enables direct assessment of support from the matrix, providing meaningful insights into the topology of the optimal trees. Moreover, the decomposition of characters into 3ts allows for precise quantification of the impact of the characters/taxa in the results. In this study, focusing on Crocodylia (a subject of ongoing debate over recent decades), we use 3ta to measure the support of specific characters and/or taxa in the recently published matrix of Rio and Mannion (Rio J.P., Mannion P.D. 2021. Phylogenetic analysis of a new morphological dataset elucidates the evolutionary history of Crocodylia and resolves the long-standing gharial problem. PeerJ 9:e12094). This conflict revolves around two competing hypotheses-Longirostres and Brevirostres-supporting a different placement of the Gavialoidea clade. We also introduce here the Relative Contradiction Index (RCI) to evaluate node support, a metric that reflects the degree of contradiction in a matrix between competing cladistic hypotheses, ranging from 0.5 (maximum contradiction) to 1 (no contradiction). We show that although the Longirostres hypothesis is best-supported, it is strongly challenged by the Brevirostres hypothesis (RCI = 0.62). Furthermore, we find that Tomistominae provides 61% of the supporting evidence for the Longirostres hypothesis, such that, when removed, the matrix supports the Brevirostres hypothesis. Individual tomistomines' contributions vary only from 2% to 7% of the total support to the Longirostres hypothesis. Finally, we show that characters correlated to longirostry only provide a fraction (22%) of the total support to the Longirostres hypothesis. Thus, our method can quantify the impact of specific characters or taxa on a phylogenetic result. This should prove very useful to phylogeneticists, especially when dealing with incomplete material such as fossils.

Pinworms (Nematoda: Oxyurida) are among the first documented zooparasitic nematodes, and some species are of veterinary, medical, and economic importance. However, the basic molecular phylogenetic framework for the Oxyurida is far from comprehensive, and the origin and early evolutionary history of the group remain little understood. In this study, phylogenomic analyses of the Oxyurida, involving the most comprehensive family-level taxon sampling of pinworms to date, were performed based on the universal single-copy orthologues and the mitochondrial protein-coding genes. Phylogenomic results yielded a highly resolved tree that confirmed the validity of the family Gyrinicolidae, suggested that the Heteroxynematidae is nested within the Oxyuridae and should be treated as a subfamily within the latter family (Heteroxynematinae status novus), and failed to support the separation of the subfamilies Oxyurinae and Syphaciinae. Using fossil-based time priors to calibrate both mitogenomic and genomic phylogenies, we establish the first comprehensive evolutionary timescale for pinworms. Our results place the most recent common ancestor of the Oxyurida in the late Devonian and further support the hypothesis that members of the vertebrate-parasitic Oxyuroidea initially parasitized reptiles and later extended their host range to mammals, and during this transition, opportunistically produced a highly specialized lineage infecting anuran tadpoles.

Homo luzonensis lived during the upper Pleistocene in the northern Philippines, east of the Wallace line. The few specimens attributed to this species show a mosaic of plesiomorphies for the genus Homo and apomorphies found in upper Pleistocene Homo species. Plesiomorphic traits could result from a close phylogenetic relationship with Australopithecus or Homo habilis/rudolfensis or from insular evolution favouring reversals, possibly linked to a relationship with a more recent species like Homo erectus. We conducted a cladistic analysis based on dental and postcranial remains of adult H. luzonensis to test these hypotheses. The trees obtained indicate that both hypotheses are supported by different anatomical elements. The trees suggesting H. luzonensis is close to H. erectus (as a sister-taxon or as a close relative of H. erectus) are supported by dental characters and feature high retention and consistency indices. Moreover, H. luzonensis likely had reduced body size and postural/locomotor modifications, similar to other insular mammals with medium-to-large-sized ancestors. The tropical forest environment of Luzon Island may have favoured the selection of these features. Based on these results and our current knowledge of insular evolution, we suggest that H. luzonensis likely evolved from an Asian H. erectus population in an insular context.

This study presents the first phylogenetic analysis focused on the Neotropical genera of the subtribe Hylobiina, including species of 28 out of the 29 currently recognized genera. A morphological data matrix comprising 131 terminal taxa and 162 characters was analysed under maximum parsimony using a heuristic search with extended implied weighting, resulting in a single most parsimonious tree. The analysis recovered Myrtacebius as unrelated to the remaining genera of the group. The genera Arniticus, Byzes, Calvertius, Centor, Cyriaspis, Haplogenus, Heilipus, Heilus, Hilipinus, Iphipus, Ischiomastus, Lymanchonus, Marshallius, Neseilipus, Nothofagius, Ozoctenus, Placeilipus, Plethes, Polymicrus, Pseudanchonus, Syphorbus, Tartarisus and Typacrus were recovered as monophyletic, whereas Epistrophus, Heilipodus, Parabyzes and Rhineilipus were found to be non-monophyletic. Based on these results, Whiteheadlobius gen. nov. is proposed, supported by the presence of a ventrite-femoral stridulatory system of type 2. This genus includes the following species, formerly placed in Heilipodus: Whiteheadlobius argentinicus, comb. nov., W. bajulus, comb. nov., W. biplagiatus, comb. nov., W. cinctipennis, comb. nov., W. clavipes, comb. nov., W. destructor, comb. nov., W. naevulus, comb. nov., and W. unifasciatus, comb. nov. In addition, Rhineilipus is redefined to include Parabyzes, now considered a junior synonym, and several species formerly assigned to Heilipodus are transferred to Rhineilipus: R. austerus, comb. nov., R. caliginosus, comb. nov., R. callosus, comb. nov., R. cynicus, comb. nov., R. decussatus, comb. nov., R. jocosus, comb. nov., R. lutosus, comb. nov., R. quadrinodosus, comb. nov., and R. suspensus. An updated identification key to the Neotropical genera of Hylobiina is also provided.

Sphaenorhynchini comprises 15 species of small, greenish treefrogs from cis-Andean South America. Araujo-Vieira et al. (2019, A total evidence analysis of the phylogeny of hatch-faced treefrogs [Anura: Hylidae: Sphaenorhynchus], Cladistics 35, 469-486) conducted a total evidence parsimony analysis of DNA sequences and phenotypic data, corroborating the monophyly of Sphaenorhynchus, identifying three species groups, and placing the unusual species S. pauloalvini as sister to all other species. On this basis and numerous phenotypic differences, Araujo-Vieira et al. (2020, A new genus of lime treefrogs [Anura: Hylidae: Sphaenorhynchini], Zool. Anz. 286, 81-89) erected the genus Gabohyla for S. pauloalvini. Subsequently, Pereira et al. (2022, The dispersal between Amazonia and Atlantic Forest during the Early Neogene revealed by the biogeography of the treefrog tribe Sphaenorhynchini [Anura, Hylidae], Ecol. Evol. 12, e8754) performed a Bayesian analysis of a subset of Araujo-Vieira et al.'s (2019) molecular data and found G. pauloalvini to be nested within Sphaenorhynchus, which they attributed exclusively to choice of analytical method. To test this claim, we performed parsimony and Bayesian analyses of the total evidence dataset and the complete and partial molecular datasets with either the entire outgroup sample or a single terminal. The topology from the Bayesian analysis of the complete dataset is almost identical to that of Araujo-Vieira et al. (2019), with G. pauloalvini sister to Sphaenorhynchus, thereby refuting Pereira et al.'s claim. Moreover, the monophyly of Sphaenorhynchus sensu stricto was remarkably robust, being recovered in all analyses except the Bayesian analysis of the partial molecular dataset with a single outgroup terminal (i.e., the analysis performed by Pereira et al.). In addition to supporting the continued recognition of Gabohyla, our results underscore the importance of considering not only the choice of analytical method, but also character and taxon sampling-including outgroup sampling-before rejecting prior findings.

We present the most comprehensive revision to date of the Neotropical false dragon millipede tribe Cornalatini Verhoeff, 1941. We (1) test the monophyly of Cornalatini through a morphology-based cladistic analysis; (2) conduct the first molecular study to extensively sample Chelodesmidae across multiple taxa and gene regions in a phylogenetic context; and (3) revise the taxonomy of the tribe. Our morphology-based phylogenetic analysis, in which 56 morphological characters were scored across 11 ingroup and 9 outgroup terminals, recovered 6 synapomorphies supporting the monophyly of the tribe and providing the basis for a revised classification of the group. In addition, we provide the first molecular analysis of Chelodesmidae, based on the nuclear EF1α gene, including six ingroup and four outgroup species, and discuss implications for future phylogenetic studies of the family. Based on our results, we include within Cornalatini the genera Cornalatus Attems, 1931, Leodesmus Mauriès & Geoffroy, 2000, Obiricodesmus Schubart, 1955, Pseudoleptodesmus Brölemann, 1902, and the newly proposed genera Monidracodesmusgen. nov. and Pseudodracodesmusgen. nov. We also describe three new species for the tribe, Leodesmus acutussp. nov. and Leodesmus alambarisp. nov. from limestone caves in São Paulo state, Brazil, and Monidracodesmus maysp. nov. from forested habitats in Bahia state, Brazil. We recognize Cornalatus tabulus Hoffman, 1990 as a junior synonym of Cornalatus permutatus (Attems, 1938), and Obiricodesmus terrigena (Attems, 1943) and Obiricodesmus brasiliae (Brölemann, 1902) as junior synonyms of Obiricodesmus rosascens (Brandt, 1839). Our study clarifies the taxonomy of Cornalatini and provides a solid framework for future studies of Chelodesmidae. ZooBank: urn:lsid:zoobank.org:pub:1D7C09AC-DA1D-4453-BA5D-5F2A28501FD5.

SWEETs (Sugars Will Eventually be Exported Transporters) represent a distinct category of proteins responsible for mediating intracellular sugar transport. These transporters are involved in sugar allocation processes, contribute to plant growth and development, and mediate adaptive responses to abiotic and biotic stresses. Despite extensive research on SWEET genes in many plant species, their functions in perennial ryegrass have not been clearly characterized. In this study, genome-wide bioinformatic analyses were conducted to identify SWEET family members in perennial ryegrass (Lolium perenne; LpSWEETs) and to explore their potential involvement in drought stress responses. Twenty-three LpSWEET genes were identified based on whole-genome sequence data, and phylogenetic inference indicated that these genes clustered into four clades. Comprehensive analyses of gene organization, conserved motifs, cis-regulatory elements, and protein features demonstrated strong evolutionary conservation across LpSWEET members, while quantitative real-time PCR analysis demonstrated that LpSWEET13 exhibited drought-responsive expression, and subcellular localization analysis showed that LpSWEET13 was localized in the plasma membrane. Under drought stress, transgenic Arabidopsis thaliana lines overexpressing LpSWEET13 presented a substantially higher survival rate than their corresponding wild-type controls. In addition, ectopic expression of LpSWEET13 increased expression levels of AtP5CS1, AtRD22, AtRD29A, and AtRD29B expression. These findings offer insights into the cladistic characteristics of the LpSWEET family and establish a useful framework for subsequent functional studies of LpSWEET genes.

Automated insect identification systems hold significant value for biodiversity monitoring, pest management, citizen science initiatives and systematic studies, particularly in an era of declining expertise in insect taxonomy. However, current deep learning approaches often rely on standardized specimen photos from limited-angles and simplified backgrounds, limiting their generalization and effectiveness in diverse practical scenarios. Here, we address this limitation using assassin bugs (Hemiptera: Reduviidae) as a model system-a highly diverse group with complex morphological variation. We developed a comprehensive, high-quality dataset of 11 915 expert-validated images from 92 species across 48 genera and six subfamilies, integrating three image types: standard, turntable-captured and ecological. Using ConvNeXt-B architecture, we systematically evaluated the performance of classification and hierarchical categorization to higher taxonomic ranks across different training and testing scenarios. Multi-angle fusion increased species recognition accuracy by 5.72% and F1-score by 0.061 and increased the hierarchical categorization of unseen species to correct genera by 13.53% and the F1-score by 0.129. Incorporating ecological images further enhanced model performance by 13% for both tasks. Grad-CAM visualization revealed that multi-angle, cross-domain fusion guides the model to focus on taxonomically diagnostic traits, yielding hierarchical feature representations aligned with classical taxonomy across lab and wild environments. Our results demonstrate that integrating diverse viewing angles and ecological contexts substantially improves model cross-domain adaptation, providing a practical framework for developing reliable automated insect identification tools for diverse practical scenarios. Furthermore, our model's ability to accurately categorize unseen taxa into higher taxonomic ranks holds significant potential for future applications in systematics, including facilitate specimen sorting and generating testable phylogenetic hypotheses.