Interspecific Genetic Variation Research Articles

Evolution of a novel adrenal cell type that promotes parental care.

Cell types with specialized functions fundamentally regulate animal behaviour, and yet the genetic mechanisms that underlie the emergence of novel cell types and their consequences for behaviour are not well understood1. Here we show that the monogamous oldfield mouse (Peromyscus polionotus) has recently evolved a novel cell type in the adrenal gland that expresses the enzyme AKR1C18, which converts progesterone into 20α-hydroxyprogesterone. We then demonstrate that 20α-hydroxyprogesterone is more abundant in oldfield mice, where it induces monogamous-typical parental behaviours, than in the closely related promiscuous deer mice (Peromyscus maniculatus). Using quantitative trait locus mapping in a cross between these species, we ultimately find interspecific genetic variation that drives expression of the nuclear protein GADD45A and the glycoprotein tenascin N, which contribute to the emergence and function of this cell type in oldfield mice. Our results provide an example by which the recent evolution of a new cell type in a gland outside the brain contributes to the evolution of social behaviour.

Geometric morphometrics to differentiate species and explore seasonal variation in three Mansonia species (Diptera: Culicidae) in central Thailand and their association with meteorological factors.

Mansonia mosquito species are recognised as a significant vector of human pathogens, primarily transmitting the filarial nematode, Brugia malayi. In central Thailand, the three most prevalent Mansonia species are Mansonia annulifera, Mansonia indiana and Mansonia uniformis. This study explored the influence of seasonal changes on the phenotypic variation of these Mansonia species in central Thailand using the geometric morphometrics (GM). To ensure accurate species identification, we integrated GM techniques with DNA barcoding, examining distinctions in both phenotype and genotype among the species. The intraspecific genetic divergence ranged from 0.00% to 1.69%, whereas the interspecific genetic divergence ranged from 10.52% to 16.36%. The clear distinction between intra- and interspecific distances demonstrated the presence of a barcoding gap, confirming the successful differentiation of the three Mansonia mosquito species through DNA barcoding. Similarly, the interspecies GM assessment for classifying Mansonia species demonstrated a high degree of accuracy, with an overall performance of 98.12%. Exploring seasonal variation in the three Mansonia species revealed wing variations across different seasons, and pronounced variations appearing in the cool season. Regarding their association with meteorological factors, Ma. annulifera and Ma. uniformis showed significant positive correlations with temperature (p < 0.05), and Ma. uniformis also displayed a significant negative correlation with atmospheric pressure (p < 0.05). The insights from this study will deepen our understanding of the adaptive patterns of Mansonia mosquitoes in Thailand's central region, paving the way for enhanced disease surveillance related to these vectors.

DNA Barcoding Supports "Color-Pattern''-Based Species of Stictochironomus from China (Diptera: Chironomidae).

The genus Stictochironomus (Diptera: Chironomidae) has an almost worldwide distribution, with more than 30 species. However, species delimitation and identification based on the markings on the wings and legs are controversial and uncertain. In this study, we focused on color patterns to review the adults of the genus from China, and two new species (S. trifuscipes sp. nov. and S. quadrimaculatus sp. nov.) are described and figured. DNA barcodes can accurately separate the two new species with specific color patterns. However, heterospecific individuals form a monophyletic cluster in the phylogeny tree. For example, S. maculipennis (Meigen) and S. pictulus (Meigen), which have a lower interspecific genetic divergence, form a single clade. Sequences with the same species name but with high intraspecific distance form more than one phylogenetic clade, such as S. sticticus (Fabricius) of three clades, S. pictulus of four clades, S. akizukii (Tokunaga) and S. juncaii Qi, Shi, and Wang of two clades, might have potential cryptic species diversity. Species delimitation analysis using ASAP, PTP, and GMYC clearly delineated them as separate species. Consequently, color patterns are a good diagnostic characteristic for species delimitation in Stictochironomus. The distance-based analysis shows that a threshold of 4.5-7.7% is appropriate for species delimitation in Stictochironomus. Additionally, an updated key including color pattern variation for male adults of known Stictochironomus species from China is provided.

The value of hybrid genomes: Building two highly contiguous reference genome assemblies to advance Canis genomic studies.

Previous studies of canid population and evolutionary genetics have relied on high-quality domestic dog reference genomes that have been produced primarily for biomedical and trait mapping studies in dog breeds. However, the absence of highly contiguous genomes from other Canis species like the gray wolf and coyote, that represent additional distinct demographic histories, may bias inferences regarding inter-specific genetic diversity and phylogenetic relationships. Here, we present single haplotype de novo genome assemblies for the gray wolf and coyote, generated by applying the trio-binning approach to long sequence reads generated from the genome of a female first-generation hybrid produced from a gray wolf and coyote mating. The assemblies were highly contiguous, with contig N50 sizes of 44.6Mb and 42.0Mb for the wolf and coyote, respectively. Genome scaffolding and alignments between the two Canis assemblies and published dog reference genomes showed near complete collinearity, with one exception: a coyote-specific chromosome fission of chromosome 13 and fusion of the proximal portion of that chromosome with chromosome 8, retaining the Canis-typical haploid chromosome number of 2n=78. We evaluated mapping quality for previous RAD-seq data from 334 canids and found nearly identical mapping quality and patterns among canid species and regional populations regardless of the genome used for alignment (dog, coyote, or gray wolf). These novel wolf and coyote genome reference assemblies will be important resources for proper and accurate inference of Canis demography, taxonomic evaluation, and conservation genetics.

DNA barcoding of Notopterygii Rhizoma et Radix (Qiang-huo) and identification of adulteration in its medicinal services

Safety concerns, stemming from the presence of complex and unpredictable adulterants, permeate the entire industrial chain of traditional Chinese medicines (TCMs). The Notopterygii Rhizoma et Radix (NReR) from the Apiaceae family, commonly known as “Qiang-huo”, is a widely used herbal medicine. The recent surge in its demand has given rise to a proliferation of counterfeit and substituted products in the market. Traditional identification presents inherent limitations, while DNA mini-barcoding, reliant on sequencing a short-standardized region, has received considerable attention as a new potential means to identify processed medicinal materials. In this study, we constructed a comprehensive Internal Transcribed Spacer 2 (ITS2) matrix encompassing genuine NReR and their commonly found adulterants for the first time. Leveraging this matrix, we conducted a thorough assessment of the genetic profiles and sources of NReR available in the Chinese herbal medicine market. Following established DNA barcoding protocols, the intra-specific genetic divergences within NReR species were found to be lower than the inter-specific genetic divergences from other species. Among the 120 samples that were successfully amplified, ITS2 exhibits an outstanding species-level identification efficiency of 100% when evaluated using both the BLASTN and neighbor-joining (NJ) tree methods. We concluded that ITS2 is a mini-barcode that has shown its potential and may become a universal mini-barcode for the quality control of “Qiang-huo”, thereby ensuring the safety of clinical medication.

A Community-Based Framework Integrates Interspecific Interactions into Forest Genetic Conservation

Forest genetic conservation is typically species-specific and does not integrate interspecific interaction and community structure. It mainly focuses on the theories of population and quantitative genetics. This approach depicts the intraspecific patterns of population genetic structure derived from genetic markers and the genetic differentiation of adaptive quantitative traits in provenance trials. However, it neglects possible interspecific interaction in natural forests and overlooks natural hybridization or subspeciation. We propose that the genetic diversity of a given species in a forest community is shaped by both intraspecific population and interspecific community evolutionary processes, and expand the traditional forest genetic conservation concept under the community ecology framework. We show that a community-specific phylogeny derived from molecular markers would allow us to explore the genetic mechanisms of a tree species interacting with other resident species. It would also facilitate the exploration of a species’ ecological role in forest community assembly and the taxonomic relationship of the species with other species specific to its resident forest community. Phylogenetic β-diversity would assess the similarities and differences of a tree species across communities regarding ecological function, the strength of selection pressure, and the nature and extent of its interaction with other species. Our forest genetic conservation proposal that integrates intraspecific population and interspecific community genetic variations is suitable for conserving a taxonomic species complex and maintaining its evolutionary potential in natural forests. This provides complementary information to conventional population and quantitative genetics-based conservation strategies.

Integrated Identification and Genetic Diversity of Potentially Invasive Clearwing Moths (Lepidoptera: Cossoidea: Sesiidae) in Korea.

The populations of clearwing moth borers in Korea have recently caused extensive and severe damage to pin oaks (Quercus palustris Munchh.). We conducted field monitoring and molecular analyses to identify them in an integrated manner. Morphological examination and molecular analyses of the COI gene, based on intra- and interspecific genetic divergences (GDs), revealed that the borers were identified as two invasive species, Sphecodoptera sheni and Paranthrenella pinoakula sp. nov. The maximum intraspecific GD was found to be 1.9%, whereas the minimum interspecific GD was confirmed as 8.1%, indicating a distinct barcoding gap. Both the MJ network and NJ tree also showed that 18 haplotypes (Hs) were detected from the 52 COI sequences. The borers revealed a total of 17 Hs: (i) H1-H7 were detected in all seven regions with S. sheni; (ii) Wonju and Goyang populations of S. sheni revealed more than three Hs; (iii) H7 was closely connected with H8 of the Chinese population of S. sheni; (iv) H9-H10 were detected in other samples from the Wonju population with P. pinoakula sp. n. and were closely located with congeneric species. A maximum likelihood tree also revealed that P. pinoacula sp. n. nested within the congeneric species, genetically separating from S. sheni.

DNA barcoding and phylogenetic relationships of ten butterfly caterpillars

Cytochrome C oxidase subunit I (COI), known as DNA barcodes, can be employed for the identification of an unknown specimen at the species level. The present study was aimed at performing COI gene-based identification of butterflies using butterfly caterpillars. Consecutively, ten caterpillars of ten different butterfly species from the families Papilionidae, Nymphalidae, Pieridae, Lycaenidae, and Hesperiidae were taken from respective host plants and used to generate COI gene sequences that were about 650 bp long. After BLAST analysis, the sequenced gene revealed 96–100% similarity to the same species from different regions. Then, sequences were submitted to NCBI's GenBank and obtained ten accession numbers. In order to elucidate genetic diversity and evolutionary relationships among ten species of butterfly caterpillars, pairwise distance analysis and the construction of a phylogenetic tree were performed using MEGA10 and BioEdit software. In the analysis, the interspecific genetic divergence among the caterpillars of butterflies was between 0.101-0.164%. A phylogenetic tree was constructed with the assistance of the Neighbor-Joining (NJ) algorithm, which identified two major clades, A and B, as well as indicated that butterflies caterpillars shared a common ancestor. All the species are included in these two clades, except Catopsilia pomona. This species is under the family Pieridae, and the phylogenetic position of Pieridae compared to other butterfly families is ambiguous, necessitating additional research to resolve this issue. The study demonstrated the general applicability of DNA barcoding for rapidly and accurately distinguishing butterfly species, even when using larval stages, as in the present study. Furthermore, it may disclose a higher taxonomic hierarchy of butterfly families. Asian Australas. J. Biosci. Biotechnol. 2023, 8(3), 49-55

Phylogeny, biogeography, and integrative taxonomic revision of the Afro-Arabian rodent genus Ochromyscus (Muridae: Murinae: Praomyini)

Abstract The analyses of Plio-Pleistocene speciation processes in the Horn of Africa are relevant for understanding the evolution of biodiversity patterns of this understudied part of the world. Here we analyse comprehensive genomic and morphological data of the recently delimited murid genus Ochromyscus, one of the few with Afro-Arabian distribution. Using an integrative taxonomic approach, we delimit three species in the genus: two in eastern Africa (O. brockmani and O. niveiventris) and one in southern Arabia (O. yemeni), and detail their distribution, genetic structure, and evolutionary history. Despite their morphological similarity, the three species split before the Pleistocene, and their interspecific genetic divergence level is comparable to that between sister genera of murine rodents. The split between two taxa living on opposite sides of the Red Sea (O. brockmani vs. O. yemeni) is younger than the separation of their ancestor and O. niveiventris living in eastern Africa. The colonization of Arabia can be explained either by the presence of a relatively recent continental bridge or by the past occurrence of the genus along the eastern coast of the Red Sea and subsequent spreading through the Sinai Peninsula.

Effect on genetic diversity of the absence of intraspecies preference in 2 sympatric Reticulitermes termite species (Isoptera: Rhinotermitidae).

The recombinant genotypes that can be produced when closely related species mate improve the genetic diversity of the population. Among closely related species, the link between interspecific reproduction behaviors and genetic diversity has barely been studied. Reticulitermes chinensis and R. flaviceps, which live close to each other, were used as research subjects in our study to find out how preferring conspecifics affects reproductive behavior between species. We discovered that neither R. chinensis nor R. flaviceps displayed preference behavior for conspecifics. Males of R. chinensis and R. flaviceps chased and groomed not only intraspecific females but also interspecific females. In a brief period of time, 2 mating behaviors, intra- and interspecific mating, were also observed. There were no significant differences in the duration of each behavior (tandem, grooming, and mating) between interspecies and intraspecies partners. Moreover, genetic analysis showed both interspecific mating and intraspecific mating can produce living offspring when the 2 types of mating occur in a colony. Our findings showed that there was no obvious intraspecific preference between the 2 species of termite Reticulitermes when it came to tandem, grooming, and mating, which not only makes it easier for interspecific hybridization to occur but also sheds light on the genetic diversity.

Phylogenetic analysis of Aciagrion Selys (Odonata: Coenagrionidae)

ABSTRACT Odonates are useful biological indicators of environmental health because of their pollution-free habitat requirements and amphibiotic life cycle. Due to habitat destruction by industrial development, there is a need to name these odonates and obtain their genetic data to be used in understanding their evolutionary history for biodiversity conservation. Aciagrion is a poorly known and taxonomically difficult genus of oriental damselflies. Species of this genus cannot be distinguished on the basis of morphological characters alone as they are morphologically similar to the damselflies of other genera (Ischnura and Amphiallagma) and may also be referred to as cryptic species. Here, therefore, molecular studies are carried out to distinguish the species of this genus. The phylogenetic relationships of five species of genus Aciagrion have been explored using molecular (based on concatenated sequences of mitochondrial genes- COI, ND1 and 16S rRNA genes) as well as external morphological characters. Single-linkage cluster analysis of morphological data sets did not explain the relationships appropriately among the species of this genus as outgroup species were also retrieved within ingroup species. Interspecific genetic divergence, conserved, variable, parsimony-informative sites, nucleotide base composition and transition/transversion bias based on concatenated gene sequences have been calculated for these species. It is found that a multigene concatenation approach interprets phylogeny more appropriately than the morphological data alone. Presently, a COI gene fragment sequence for one species (the endemic Aciagrion hisopa), 16S rRNA gene fragments for four species and ND1 gene fragments for five species have been submitted for the first time to GenBank, and phylogenetic relationships based on three genes have also been determined for the first time. Aciagrion migratum is a new record from India.

Phylogenetic analyses and description of a new species of black widow spider of the genus Latrodectus Walckenaer (Araneae, Theridiidae) from Mexico; one or more species?

A new species of the spider genus Latrodectus Walckenaer, 1805 from Mexico is described based on an integrative taxonomic approach. Latrodectus occidentalis Valdez-Mondragón sp. nov. is described using the molecular markers cytochrome c oxidase subunit 1 (CO1) and internal transcribed spacer 2 (ITS2), morphology of male and female specimens, and Species Distribution Models (SDM). Four molecular methods for species delimitation were implemented. The new species is characterized by having a unique dorsal coloration pattern on the abdomen. Latrodectus occidentalis sp. nov. is considered a distinct and valid species for four reasons: (1) it can be distinguished by morphological characters (genital and somatic); (2) the average interspecific genetic variation is &gt; 2%; (3) 12 haplotypes were recovered within the species, being separated by the next close haplogroup of L. hesperus Chamberlin &amp; Ivie, 1935 (30 mutations); and (4) congruence was observed among the four molecular methods. The number of recorded species of Latrodectus from Mexico increases to four: Latrodectus mactans (Fabricius, 1775), L. hesperus Chamberlin &amp; Ivie, 1935, L. geometricus C.L. Koch, 1841 (introduced), and L. occidentalis sp. nov. The diversity of the genus Latrodectus from Mexico is surely underestimated, and more sampling is needed from the different biogeographical provinces and ecoregions to fill in these gaps.

Deepest known novel species of the genus Ophiuroglypha Hertz, 1927 (Echinodermata: Ophiuroidea) from the central rift zone, Philippine Sea

A new species of brittle star was collected in 2021 by the manned submersible “Fendouzhe” from the central rift zone deep waters, Philippine Sea, at a depth of 7729 m. It is described as Ophiuroglypha fendouzhe sp. nov., and is distinguished from its congeners based on the following features: slender arms, separated dorsal and ventral arm plates, overlapping large disc scales, and distally contiguous radial shields. We provide comprehensive descriptions of the external morphological features, including characteristics of the arm skeleton, and a phylogenetic analysis based on COI sequences. The interspecific genetic distance variation in the genus Ophiuroglypha found in this study was 3.89% to 24.25%. The new species constitutes the deepest known record for the genus Ophiuroglypha.

Molecular characterization and genetic diversity of three Stomoxys flies S. bengalensis, S. calcitrans, and S. sitiens (Diptera: Muscidae) in Central Thailand.

Stomoxys flies (Diptera: Muscidae) are hematophagous ectoparasites of medical and veterinary importance. In this study, three Stomoxys species, i.e. S. bengalensis, S. calcitrans, and S. sitiens, were collected from three provinces in Central Thailand with the aim of estimating the genetic divergence between species, for species identification, as well as within species, for a genetic diversity study based on the cytochrome c oxidase subunit I (COI) gene. Our results showed that the average intraspecific genetic divergences of Stomoxys flies ranged from 0.11% in S. sitiens to 0.98% in S. calcitrans, whereas the average interspecific genetic divergences ranged from 5.24% between S. sitiens and S. bengalensis to 6.69% between S. calcitrans and S. bengalensis. In addition, there was no overlap between the intraspecific and interspecific genetic divergences. The COI sequence analysis revealed a high haplotype diversity and low nucleotide diversity, reflecting a rapid population expansion after past bottlenecks. Moreover, there was no significant difference (P>0.05) in the pairwise population differentiation (Fst) among Stomoxys flies in Central Thailand, because of the lack of natural barriers, thus allowing genetic exchange between them. The monitoring of the haplotype network revealed that two lineages of S. calcitrans in Central Thailand were distributed in all study areas, including the Nakhon Pathom, Pathum Thani, and Saraburi Provinces. These findings may improve our understanding of the genetic patterns of these three Stomoxys flies, as well as the underlying biological mechanisms, which is knowledge that can be used for further effective control of these flies.

Comprehensive DNA barcode reference library and optimization of genetic divergence threshold facilitate the exploration of species diversity of green lacewings (Neuroptera: Chrysopidae).

Chrysopidae are a family of Neuroptera of significant importance in biocontrol against agricultural pests because of their predatory larvae. Currently, the taxonomy of Chrysopidae lacks a comprehensive revision, which impedes the exploration of species diversity as well as the selection and the conservation of green lacewings as biocontrol agents. We have established a DNA barcode reference library of the Chinese green lacewings based on an approximately complete sampling (95.63%) in 25 of the 34 provincial regions in China, comprising 1119 barcodes of 25 genera and 197 species (representing 85% genera and 43.62% species from China). Combining other 1049 high quality green lacewing DNA barcodes, we first inferred the optimal threshold of interspecific genetic divergence (1.87%) for successful species identification in multiple simulated scenarios based on present data. We further inferred the threshold of genetic divergence (7.77%) among genera with biocontrol significance. The inference and performance of the threshold appears to be mainly associated with the completeness of sampling, the proportion of closely related species, and the analytical approaches. Six new combinations, Apertochrysa platypa (Yang & Yang, 1991) comb. nov., Apertochrysa shennongana (Yang & Wang, 1990) comb. nov., Apertochrysa pictifacialis (Yang, 1988) comb. nov., Apertochrysa helana (Yang, 1993) comb. nov., Plesiochrysa rosulata (Yang & Yang, 2002) comb. nov., and Signochrysa hainana (Yang & Yang, 1991), are proposed according to integrative species delimitation. Our library and optimal threshold will effectively facilitate the exploration of species diversity of green lacewings. Our study also provides a methodological reference in molecular delimitation of other insects.

Spineless and overlooked: DNA metabarcoding of autonomous reef monitoring structures reveals intra- and interspecific genetic diversity in Mediterranean invertebrates.

The ability to gather genetic information using DNA metabarcoding of bulk samples obtained directly from the environment is crucial to determine biodiversity baselines and understand population dynamics in the marine realm. While DNA metabarcoding is effective in evaluating biodiversity at community level, genetic patterns within species are often concealed in metabarcoding studies and overlooked for marine invertebrates. In the present study, we implement recently developed bioinformatics tools to investigate intraspecific genetic variability for invertebrate taxa in the Mediterranean Sea. Using metabarcoding samples from Autonomous Reef Monitoring Structures (ARMS) deployed in three locations, we present haplotypes and diversity estimates for 145 unique species. While overall genetic diversity was low, we identified several species with high diversity records and potential cryptic lineages. Further, we emphasize the spatial scale of genetic variability, which was observed from locations to individual sampling units (ARMS). We carried out a population genetic analysis of several important yet understudied species, which highlights the current knowledge gap concerning intraspecific genetic patterns for the target taxa in the Mediterranean basin. Our approach considerably enhances biodiversity monitoring of charismatic and understudied Mediterranean species, which can be incorporated into ARMS surveys.

COI barcoding provides reliable species identification and pinpoints cryptic diversity in Western Palearctic amphibians

Abstract Assembling DNA barcode reference libraries for various taxonomic groups allows researchers to use metabarcoding or environmental DNA approaches to gain a rapid understanding of diversity in given environments. However, our ability to use reference libraries depends on how accurately DNA barcodes are able to recover taxonomic boundaries and identify species, which is rarely considered. We constructed an extensive COI barcoding library for amphibians of the Western Palearctic and successfully recovered barcodes from 60 urodele and 73 anuran species (representing 94% and 98% of the nominal anuran and urodele species in the Western Palearctic, respectively), covering the intraspecific diversity of the majority of species in this region. We tested the effectiveness of our assembled DNA barcode dataset for species identification using barcoding gap, efficiency analyses, and two phylogenetic species delimitation methods. We obtained DNA barcodes for 1251 specimens (691 anurans and 560 urodeles) with a high success rate (92-96%) of species identification. The absence of a barcoding gap in a number of samples was linked to species misidentifications, which suggest incipient speciation or cryptic diversity, or previously described mitochondrial introgression events. The phylogenetic species delimitation methods resulted in substantial oversplitting of currently accepted taxonomy. This COI barcoding library provides an almost complete and reliable reference library for Western Palearctic amphibians. We highlight the importance of generating comprehensive and well curated reference libraries that include intra- and interspecific genetic variability and the need of detailed taxonomic revision when ambiguous or incorrect DNA barcodes exist.

Comparative genomics of the Liberibacter genus reveals widespread diversity in genomic content and positive selection history.

'Candidatus Liberibacter' is a group of bacterial species that are obligate intracellular plant pathogens and cause Huanglongbing disease of citrus trees and Zebra Chip in potatoes. Here, we examined the extent of intra- and interspecific genetic diversity across the genus using comparative genomics. Our approach examined a wide set of Liberibacter genome sequences including five pathogenic species and one species not known to cause disease. By performing comparative genomics analyses, we sought to understand the evolutionary history of this genus and to identify genes or genome regions that may affect pathogenicity. With a set of 52 genomes, we performed comparative genomics, measured genome rearrangement, and completed statistical tests of positive selection. We explored markers of genetic diversity across the genus, such as average nucleotide identity across the whole genome. These analyses revealed the highest intraspecific diversity amongst the 'Ca. Liberibacter solanacearum' species, which also has the largest plant host range. We identified sets of core and accessory genes across the genus and within each species and measured the ratio of nonsynonymous to synonymous mutations (dN/dS) across genes. We identified ten genes with evidence of a history of positive selection in the Liberibacter genus, including genes in the Tad complex, which have been previously implicated as being highly divergent in the 'Ca. L. capsica' species based on high values of dN.

Goldenrod herbariomics: Hybrid-sequence capture reveals the phylogeny of Solidago.

The phylogenetic relationships among the ca. 138 species of goldenrods (Solidago; Asteraceae) have been difficult to infer due to species richness, and shallow interspecific genetic divergences. This study aims to overcome these obstacles by combining extensive sampling of goldenrod herbarium specimens with the use of a custom Solidago hybrid-sequence capture probe set. A set of tissues from herbarium samples comprising ca. 90% of Solidago species was assembled and DNA was extracted. A custom hybrid-sequence capture probe set was designed, and data from 854 nuclear regions were obtained and analyzed from 209 specimens. Maximum likelihood and coalescent approaches were used to estimate the genus phylogeny for 157 diploid samples. Although DNAs from older specimens were both more fragmented and produced fewer sequencing reads, there was no relationship between specimen age and our ability to obtain sufficient data at the target loci. The Solidago phylogeny was generally well-supported, with 88/155 (57%) nodes receiving ≥95% bootstrap support. Solidago was supported as monophyletic, with Chrysoma pauciflosculosa identified as sister. A clade comprising Solidago ericameriodes, Solidago odora, and Solidago chapmanii was identified as the earliest diverging Solidago lineage. The previously segregated genera Brintonia and Oligoneuron were identified as placed well within Solidago. These and other phylogenetic results were used to establish four subgenera and fifteen sections within the genus. The combination of expansive herbarium sampling and hybrid-sequence capture data allowed us to quickly and rigorously establish the evolutionary relationships within this difficult, species-rich group.

Shedding light on the controversial taxonomic status of Culicoides jamaicensis and Culicoides paolae (Diptera: Ceratopogonidae): an overseas trip among continents.

Culicoides biting midges (Diptera: Ceratopogonidae) are small bloodsucking flies that act as vectors for various pathogens of medical and veterinary importance. This study aimed to examine, using a comprehensive approach, the controversial taxonomic status of 2 Culicoides species that are currently distributed in the Neotropical (Culicoides jamaicensis Edwards) and Palearctic (Culicoides paolae Boorman) areas and possess unique and distinctive features. Previous investigations based on morphological analysis have suggested that these 2 species may be synonyms. Our work updated the current geographical distribution of both species and analyzed new specimens from different geographic origins, together with publicly available sequences. We used 2 universal genetic markers (COI and 28S) to test this hypothesis. Our study reveals evidence that C. paolae and C. jamaicensis belong to the same species due to the following statements: (i) similar morphological features; (ii) low interspecific genetic variation; (iii) association with a single genetic cluster; (iv) inclusion within the subgenus Drymodesmyia, which has only been recorded in the New World; and (v) occurrence in habitats with moderate temperatures. We recommend that European and African specimens of C. paolae be considered from now on as C. jamaicensis. Our comprehensive approach shed new light on the taxonomic status of these 2 Culicoides species and has implications for future studies on their biology and ecology.