Nuclear Sequences Research Articles

Hidden diversity in eastern North America: The genus Ligidium (Oniscidea, Ligiidae) in the southern Appalachian Mountains

AbstractThe terrestrial isopod genus Ligidium includes 58 species from Europe, Asia, and North America. In Eastern North America four species are recognized: L. floridanum and L. mucronatum, known just from their type localities in Florida and Louisiana respectively, L. blueridgensis, endemic to the southern Appalachians, and L. elrodii, widespread from Georgia to Ontario. The genus shows a marked morphological conservatism, and species are differentiated mostly by small morphological differences; it is not always easy to determine if such variability represents inter‐ or intraspecific variation. Here, we explore the diversity of Ligidium from the southern Appalachian Mountains, exploring the congruence of morphologically defined groups with multilocus phylogenetic reconstructions and molecular species delimitation methods. We have studied a total of 130 specimens from 37 localities, mostly from the southern Appalachians, and analysed mtDNA (Cox1) and nuclear (28S, NaK) sequences. Morphologically, we recognized eight morphotypes, most of them assignable to current concepts of L. elrodii and L. blueridgensis. Phylogenetic analyses supported the evolutionary independence of all morphotypes, and suggest the existence of 8–9 species, including limited cryptic diversity. Single‐locus delimitation analyses based on mtDNA data suggest the existence of a much higher number of species than the multilocus analyses. The estimated age of the ancestors of sampled lineages indicates a long presence of the genus in eastern North America and old speciation events through the Miocene. Our results indicate a higher diversity than previously thought among the Ligidium populations present in the southern Appalachian Mountains, with several species to be described.

The phased Solanum okadae genome and Petota pangenome analysis of 23 other potato wild relatives and hybrids

Potato is an important crop in the genus Solanum section Petota. Potatoes are susceptible to multiple abiotic and biotic stresses and have undergone constant improvement through breeding programs worldwide. Introgression of wild relatives from section Petota with potato is used as a strategy to enhance the diversity of potato germplasm. The current dataset contributes a phased genome assembly for diploid S. okadae, and short read sequences and de novo assemblies for the genomes of 16 additional wild diploid species in section Petota that were noted for stress resistance and were of interest to potato breeders. Genome sequence data for three additional genomes representing polyploid hybrids with cultivated potato, and an additional genome from non-tuberizing S. etuberosum, which is outside of section Petota, were also included. High quality short reads assemblies were achieved with genome sizes ranging from 575 to 795 Mbp and annotations were performed utilizing transcriptome sequence data. Genomes were compared for presence/absence of genes and phylogenetic analyses were carried out using plastome and nuclear sequences.

Nuclear sequences of mitochondrial origin in domestic yak

Mitochondrial DNA sequences are frequently transferred into the nuclear genome, generating nuclear mitochondrial DNA sequences (NUMTs). Here, we analysed, for the first time, NUMTs in the domestic yak genome. We obtained 499 alignment matches covering 340.2 kbp of the yak nuclear genome. After a merging step, we identified 167 NUMT regions with a total length of ~ 503 kbp, representing 0.02% of the nuclear genome. We discovered copies of all mitochondrial regions and found that most NUMT regions are intergenic or intronic and mostly untranscribed. 98 different NUMT regions from domestic yak showed high homology with cow and/or wild yak genomes, suggesting selection or hybridization between domestic/wild yak and cow. To rule out the possibility that the identified NUMTs could be artifacts of the domestic yak genome assembly, we validated experimentally five NUMT regions by PCR amplification. As NUMT regions show high similarity to the mitochondrial genome can potentially pose a risk to domestic yak DNA mitochondrial studies, special care is therefore needed to select primers for PCR amplification of mitochondrial DNA sequences.

Molecular Identification, Multigenic Characterization and Phylogenetic Analysis of Ctenocephalides Canis Fleas from Humans and Domestic Animals in Iran.

Fleas belonging to the Pulicidae are prevalent ectoparasites infesting mammals and birds in Iran. This study focused on genetically identifying and characterizing Ctenocephalides canis collected both off-host and infesting humans and various domestic animals in the country. A total of 918 adult flea samples were collected from 10 sites in western and northwestern Iran between April 2018 and May 2019. Out of these, 71 specimens were found off-host, while the remaining fleas were collected from humans (121), sheep (126), goats (184), and dogs (416). Morphological identification at the genus level was performed on all fleas, and ten selected specimens selected based on the sampling sites and hosts were subjected to molecular detection at the species level by using partial amplification and sequencing of the internal transcribed spacer 1 and 2, as well as the cytochrome oxidase I (COXI) markers. The morphological identification confirmed all fleas as Ctenocephalides spp. Alignment and phylogenetic analysis of nuclear and mitochondrial partial sequences confirmed the presence of C. canis. However, molecular divergence was observed among the ten isolates based on the ITS1 and ITS2 with diversity rates estimated at 0.15% and 3.36%, respectively. Notably, the analysis of the COXI marker revealed no molecular divergence among the partial sequences representing the ten studied isolates from C. canis. This study explores the diversity of C. canis in the western and northwestern regions of Iran, providing insights into their molecular taxonomy and potential role as disease vectors in these areas.

Melanella martarum sp. nov. (Gastropoda: Eulimidae): the first parasitic deep-sea snail reported for the Salas & Gomez Ridge.

Eulimidae is a highly diverse family of gastropods that are often parasites of echinoderms. They are cosmopolitan and live from the intertidal to great depths. Despite its wide geographic and bathymetric distribution, no species of Eulimidae have been reported for the Salas & Gómez Ridge to date. In this study, we describe Melanella martarum sp. nov., which was collected during the EPIC oceanographic cruise onboard RV Mirai (JAMSTEC, Japan) in 2019. Seven specimens were collected with a modified Agassiz trawl on the summit of seamount "Pearl" (Zhemchuznaya) in the Salas & Gómez Ridge (25.59°S, 89.13°W) at 545 m depth. The morphology of M. martarum sp. nov. was compared with other Melanella species reported for the area, including Chile and Rapa Nui. DNA was extracted and partial sequences of the mitochondrial genes Cytochrome Oxidase 1 (COI) and 16S rDNA, and the nuclear gene Histone 3 (H3) were sequenced. Melanella martarum sp. nov. has morphological characteristics that separate it from other species of Melanella, such as the thickness and color of the shell, and the shape of the protoconch. In addition, M. martarum sp. nov. was genetically differentiated from other Melanella spp. sequences (uncorrected p distances from 18,1-8.6% in mitochondrial COI and 16S rDNA to 3% in nuclear H3 sequences). Although there is not much molecular data available for Eulimidae, the phylogenetic analysis confirms the results obtained by morphology, placing the species found on the Salas & Gómez Ridge within the genus Melanella. The current study advances the understanding of the poorly known benthic fauna found on seamounts in the easternmost part of the Sala & Gómez ridge, a location distinguished by a high level of endemism.

Ixeridium malingheense (Asteraceae), a new species from southwestern Guizhou, China

A new Asteraceae species, Ixeridium malingheense Z.Li & Q.Xu sp. nov., from Xingyi City, south-western Guizhou, China, is described and illustrated based on morphological and molecular analyses. Compared with the other species of the genus, the species is most similar to I. yunnanense in a small stature, linear-lanceolate stem leaves, and short phyllaries. However, it is easily distinguished from the latter by its smaller basal leaves 18–34 × 5–13 mm (vs. 10–25 × 5 mm), spatulate or long-spatulate (vs. elliptic, lanceolate, or oblanceolate), petioles ca. 30–55 mm (vs. 10 mm to absent), outer phyllaries 1-seriate (vs. 2-seriate, unequal), achenes smaller 2.0–3.0 × 0.5–1.0 mm (vs. 3.2 × 0.6 mm), and a flowering period of March to May (vs. June). Molecular phylogenetic analyses based on nuclear ITS sequence data determined the systematic position of I. malingheense in Ixeridium.

Discovery of a new Pseudalomya Telenga, 1930 (Hymenoptera, Ichneumonidae, Ichneumoninae) species from Taiwan and its implications for the systematic position of this genus

The rare genus Pseudalomya Telenga comprises two species, which are found only in the Eastern Palaearctic region and high mountains of the Oriental region. The phylogenetic position of Pseudalomya remains unclear because of its intermediate morphology between two ichneumonine tribes, Alomyini and Phaeogenini. This article reports the discovery of a new species of Pseudalomya: Pseudalomya truncaticornissp. nov. Specimens were collected during a survey of insect fauna in the Dasyueshan area of Shei-Pa National Park, one of the high-altitude regions in Taiwan. The new species can be diagnosed by its body coloration, frontal horn shape, facial punctures, metasomal tergite sculpture, and wing venation. To the best of our knowledge, this is the first record of Pseudalomya in Taiwan. This article also presents a diagnostic key to the global species of Pseudalomya. In this study, molecular phylogenetic analyses were performed using one mitochondrial and two nuclear gene sequences from P. truncaticornissp. nov. and other members of the Ichneumoniformes group. The results indicate that Pseudalomya should be classified within Phaeogenini, distinct from Alomyini, but more comprehensive phylogenomic studies are needed to confirm this placement.

Molecular Phylogenetics and the Evolution of Morphological Complexity in Aytoniaceae (Marchantiophyta).

Aytoniaceae are one of the largest families of complex thalloid liverworts (Marchantiopsida), consisting of about 70 species, with most species being distributed in temperate areas. However, the phylogeny and evolution of the morphological character of Aytoniaceae are still poorly understood. Here, we employed two chloroplast loci, specifically, rbcL and trnL-F, along with a 26S nuclear ribosomal sequence to reconstruct the phylogeny and track the morphological evolution of Aytoniaceae. Our results reveal that Aytoniaceae are monophyletic, and five monophyletic clades were recovered (i.e., Asterellopsis-Cryptomitrium, Calasterella, Mannia, Reboulia-Plagiochasma, and Asterella). Asterella was divided into five clades (i.e., Asterella lindenbergiana, subg. Saccatae, subg. Phragmoblepharis, subg. Wallichianae, and subg. Asterella), except for Asterella palmeri, which is the sister of Asterellopsis grollei. Bayesian molecular clock dating indicates that the five primary clades within Aytoniaceae underwent divergence events in the Cretaceous period. Asterellopsis differentiated during the early Upper Cretaceous (c. 84.2 Ma), and Calasterella originated from the late Lower Cretaceous (c. 143.0 Ma). The ancestral Aytoniaceae plant is reconstructed as the absence of a pseudoperianth, lacking equatorial apertures, and having both male and female reproductive organs on the main thallus. At present, Asterellopsis consists of two species known in Asia and America with the new transfer of Asterella palmeri to Asterellopsis. A new subgenus, Asterella subg. Lindenbergianae, is proposed.

Mitogenomic Analysis and Phylogenetic Implications for the Deltocephaline Tribe Chiasmini (Hemiptera: Cicadellidae: Deltocephalinae).

The grassland leafhopper tribe Chiasmini (Cicadellidae: Deltocephalinae) presently comprises 324 described species worldwide, with the highest species diversity occurring in the Nearctic region but a greater diversity of genera occurring in the Old World. In China, this tribe comprises 39 described species in 11 genera, but the fauna remains understudied. The complete mitogenomes of three species of this tribe have been sequenced previously. In order to better understand the phylogenetic position of Chiasmini within the subfamily Deltocephalinae and to investigate relationships among Chiasmini genera and species, we sequenced and analyzed the complete mitogenomes of 13 species belonging to seven genera from China. Comparison of the newly sequenced mitogenomes reveals a closed circular double-stranded structure containing 37 genes with a total length of 14,805 to 16,269 bp and a variable number of non-coding A + T-rich regions. The gene size, gene order, gene arrangement, base composition, codon usage, and secondary structure of tRNAs of the newly sequenced mitogenomes of these 13 species are highly conserved in Chiasmini. The ATN codon is commonly used as the start codon in protein-coding genes (PCGs), except for ND5 in Doratura sp. and ATP6 in Nephotettix nigropictus, which use the rare GTG start codon. Most protein-coding genes have TAA or TAG as the stop codon, but some genes have an incomplete T stop codon. Except for the tRNA for serine (trnS1(AGN)), the secondary structure of the other 21 tRNAs is a typical cloverleaf structure. In addition to the primary type of G-U mismatch, five other types of tRNA mismatches were observed: A-A, A-C, A-G, U-C, and U-U. Chiasmini mitochondrial genomes exhibit gene overlaps with three relatively stable regions: the overlapping sequence between trnW and trnC is AAGTCTTA, the overlapping sequence between ATP8 and ATP6 is generally ATGATTA, and the overlapping sequence between ND4 and ND4L is generally TTATCAT. The largest non-coding region is the control region, which exhibits significant length and compositional variation among species. Some Chiasmini have tandem repeat structures within their control regions. Unlike some other deltocephaline leafhoppers, the sequenced Chiasmini lack mitochondrial gene rearrangements. Phylogenetic analyses of different combinations of protein-coding and ribosomal genes using maximum likelihood and Bayesian methods under different models, using either amino acid or nucleotide sequences, are generally consistent and also agree with results of prior analyses of nuclear and partial mitochondrial gene sequence data, indicating that complete mitochondrial genomes are phylogenetically informative at different levels of divergence within Chiasmini and among leafhoppers in general. Apart from Athysanini and Opsiini, most of the deltocephaline tribes are recovered as monophyletic. The results of ML and BI analyses show that Chiasmini is a monophyletic group with seven monophyletic genera arranged as follows: ((Zahniserius + (Gurawa + (Doratura + Aconurella))) + (Leofa + (Exitianus + Nephotettix))).

Five new species of Pseudosperma (Inocybaceae, Agaricales) from Benin and Turkey based on morphological characteristics and phylogenetic evidence

Species of Pseudosperma (Inocybaceae) are widely distributed from temperate to tropical regions. In this study, we describe and illustrate five new species of Pseudosperma: P. beninense, P. cremeo-ochraceum, P. squarrosofulvum, P. stramineum, and P. tiliae, based on comprehensive analyses of morphological and molecular data derived from specimens collected in Benin (West Africa) and Turkey (Western Eurasia). These new species have been found in forests with Isoberlinia spp. and other ectomycorrhizal tree species in Benin and in association with Tilia platyphyllos in Turkey. The phylogenetic relationships of the new species were inferred through analyses of nuclear rDNA sequences, encompassing the internal transcribed spacer (ITS), 28S rDNA, and RNA polymerase II second largest subunit (RPB2) region. Phylogenetic analyses revealed that P. beninense, P. cremeo-ochraceum, P. squarrosofulvum, and P. stramineum from Benin cluster with species from Australia, China, and India within a clade formed exclusively by species known from the palaeotropics and Australia, whereas P. tiliae from Turkey clustered with P. mediterraneum from Italy. Detailed descriptions are provided, supplemented by illustrations and line drawings of key micromorphological features. In addition, a comparative analysis with morphologically similar and phylogenetically closely related species is presented and discussed in detail.

Leveraging new methods for comprehensive characterization of mitochondrial DNA in esophageal squamous cell carcinoma

BackgroundMitochondria play essential roles in tumorigenesis; however, little is known about the contribution of mitochondrial DNA (mtDNA) to esophageal squamous cell carcinoma (ESCC). Whole-genome sequencing (WGS) is by far the most efficient technology to fully characterize the molecular features of mtDNA; however, due to the high redundancy and heterogeneity of mtDNA in regular WGS data, methods for mtDNA analysis are far from satisfactory.MethodsHere, we developed a likelihood-based method dMTLV to identify low-heteroplasmic mtDNA variants. In addition, we described fNUMT, which can simultaneously detect non-reference nuclear sequences of mitochondrial origin (non-ref NUMTs) and their derived artifacts. Using these new methods, we explored the contribution of mtDNA to ESCC utilizing the multi-omics data of 663 paired tumor-normal samples.ResultsdMTLV outperformed the existing methods in sensitivity without sacrificing specificity. The verification using Nanopore long-read sequencing data showed that fNUMT has superior specificity and more accurate breakpoint identification than the current methods.Leveraging the new method, we identified a significant association between the ESCC overall survival and the ratio of mtDNA copy number of paired tumor-normal samples, which could be potentially explained by the differential expression of genes enriched in pathways related to metabolism, DNA damage repair, and cell cycle checkpoint. Additionally, we observed that the expression of CBWD1 was downregulated by the non-ref NUMTs inserted into its intron region, which might provide precursor conditions for the tumor cells to adapt to a hypoxic environment. Moreover, we identified a strong positive relationship between the number of mtDNA truncating mutations and the contribution of signatures linked to tumorigenesis and treatment response.ConclusionsOur new frameworks promote the characterization of mtDNA features, which enables the elucidation of the landscapes and roles of mtDNA in ESCC essential for extending the current understanding of ESCC etiology. dMTLV and fNUMT are freely available from https://github.com/sunnyzxh/dMTLV and https://github.com/sunnyzxh/fNUMT, respectively.

Dense infraspecific sampling reveals cryptic differentiation in the enigmatic hemiparasitic love vine Cassytha filiformis (Lauraceae)

AbstractSpecies delimitation remains a challenge worldwide, especially in highly diverse tropical and subtropical regions. Here, we use an integrative approach that combines morphology, phylogenomics, and species distribution modeling (SDM) to clarify the cryptic differentiation within the enigmatic hemiparasitic love vine Cassytha filiformis (Lauraceae) in China and adjacent regions. We generated complete plastid genomes and nuclear ribosomal sequences for diverse samples from across the species range and compared results with previously published plastid data, recovering two well‐supported monophyletic clades. Further, the analysis revealed significant differences in two morphological characters and SDM, indicating distinct environmental factors influencing their distributions. Fossil‐calibrated analyses to estimate the origins and diversification patterns for the cryptic species gave divergence age estimates corresponding to the Oligo‐Miocene; a period of new ecological opportunities associated with the prevailing East Asian monsoon. Multivariate analyses support the conclusion that southern China and adjacent regions have a different, previously unknown, cryptic lineage of C. filiformis. Our study highlights the importance of using multivariate approach to characterize plant species, as well as the significant role that past climatic changes have played in driving speciation in parasitic plants in tropical and subtropical zones.

Population genetic structure of Randall’s threadfin bream Nemipterus randalli in Indian waters based on mitochondrial and nuclear gene sequences

Nemipterus randalli, commonly known as Randall’s threadfin bream, is a commercially important marine finfish. Understanding its genetic structure is critical to effective management and conservation efforts. Previous investigations on population structure in this species were limited by geographic coverage. In this study, we utilized the mitochondrial Cytochrome b gene and nuclear Ribosomal protein gene intron Rp S7 sequences to investigate the population genetic structure, demography and genetic diversity of N. randalli along Indian waters. Our results revealed high haplotype diversity but low nucleotide diversity. AMOVA revealed that the variation among the population was highly significant. Hierarchical AMOVA provided further evidence of significant genetic differentiation between the west and east coasts, which was corroborated by the Bayesian tree and the median-joining network diagram. The mtDNA sequences revealed significant genetic structure between populations based on fixation index analysis following the isolation-by-distance model. Furthermore, the neutrality test and mismatch analysis suggest that N. randalli populations may have experienced a population expansion. However, nuclear marker RpS7, showed a high level of polymorphism, which obscured the population structuring observed with the mitochondrial marker. Consequently, concordant results were not obtained when comparing the mitochondrial and nuclear DNA sequences. The strong genetic differentiation between the east and west coast observed using mitochondrial marker could be attributed to a combination of geographic and environmental factors. These findings lay the groundwork for developing effective conservation and management strategies for N. randalli, considering its genetic structure.

Material Selection for Restoration of Genetic Diversity of Abies koreana on Mt. Jirisan in South Korea

: A strategy is required for selecting appropriate materials for the restoration of Abies koreana on Mt. Jirisan, where the habitat of A. koreana is continuously shrinking. The current study aimed to analyze the genetic characteristics of A. koreana in three subpopulations (Banyabong, Byeoksoryeng, and Cheonwangbong) on Mt. Jirisan using 10 nuclear simple sequence repeat (nSSR) markers and calculate the sampling distance for each subpopulation for avoiding genetically similar samples. Based on the calculated sampling distance, we proposed the size of a sample containing more than 95% of the alleles at a frequency greater than 0.05. AMOVA showed that the difference in genetic variation across subpopulations of A. koreana on Mt. Jirisan was small, approximately 3% of the total. Spatial genetic structure analysis results suggested that it would be appropriate to collect samples of the Banyabong subpopulation at intervals of 10 m or more, when sampling A. koreana, whereas for the Byeoksoryeong and Cheonwangbong subpopulations, samples should be collected at intervals of 20 m or more. Results of random sampling of 5 to 30 individuals indicated that, by applying a 10 m distance within the Banyabong subpopulation, more than 95% of the total alleles with a frequency ≥ 0.05 were secured when more than 25 individuals were extracted. Therefore, as a restoration strategy for A. koreana on Mt. Jirisan, we proposed the collection of more than 25 samples, keeping 10 m distance within the Banyabong subpopulation, which has a relatively high genetic diversity.

Morphology and phylogeny of Cortinarius strenuipes (Basidiomycota, Agaricales) reported for the first time from Türkiye

Cortinarius strenuipes Rob. Henry is reported for the first time from Türkiye based on morphological features and molecular analysis. It is found in mixed forest and distinguished by a gray or reddish-brown pileus with blackish spots, dark brownish ochre to chocolate-brown lamellae, brown or brownish-gray, cylindrical stipe slightly bulbous at base. Internal transcribed spacer region (ITS) and the large subunit (LSU) of nuclear ribosomal RNA region sequences of the specimen are determined and compared with similar taxa.

Enhanced editing efficiency in Arabidopsis with a LbCas12a variant harboring D156R and E795L mutations

AbstractCas12a (Cpf1), a Class 2 Type V CRISPR/Cas nuclease, has several unique attributes for genome editing and may provide a valuable alternative to Cas9. However, a low editing efficiency due to temperature sensitivity and insufficient cleavage activity of the Cas12a nuclease are major obstacles to its broad application. In this report, we generated two variants, ttAsCas12 Ultra and ttLbCas12a Ultra harboring three (E174R, M537R, and F870L) or two (D156R and E795L) mutations, respectively, by combining the mutations from the temperature-tolerant variants ttAsCas12a (E174R) and ttLbCas12a (D156R), and those from the highly active variants AsCas12a Ultra (M537R and F870L) and LbCas12a Ultra (E795L). We compared editing efficiencies of the five resulting Cas12a variants (LbCas12a, ttLbCas12a, ttLbCas12a Ultra, AsCas12a Ultra, and ttAsCas12 Ultra) at six target sites of four genes in Arabidopsis (Arabidopsis thaliana). The variant ttLbCas12a Ultra, harboring the D156R and E795L mutations, exhibited the highest editing efficiency of all variants tested in Arabidopsis and can be used to generate homozygous or biallelic mutants in a single generation in Arabidopsis plants grown at 22 °C. In addition, optimization of ttLbCas12a Ultra, by varying nuclear localization signal sequences and codon usage, further greatly improved editing efficiency. Collectively, our results indicate that ttLbCas12a Ultra is a valuable alternative to Cas9 for editing genes or promoters in Arabidopsis.

Exploring Genetic Diversity and Phylogenetic Relationships in Camellia reticulata Cultivars Using Novel Low-Copy Nuclear Gene Markers

This study delves into the exploration of genetic diversity and phylogenetic relationships within Camellia reticulata cultivars, providing a vital reference for horticultural research on this hetero-hexaploid species. Utilizing available transcriptome data from C. reticulata, novel low-copy nuclear gene sequences were successfully identified. With tailored primer design, these genes were amplified and sequenced from 100 C. reticulata cultivars originating from Kunming, Chuxiong, Dali, and Tengchong in China. Five distinct low-copy nuclear gene sequences were found to collectively span 3481 bp, showcasing 71 polymorphic mutation sites (Pi = 0.0077) and 91 haplotypes (Hd = 0.9974). The genetic diversity among cultivars from the four provenances ranked Tengchong > Dali > Kunming > Chuxiong. AMOVA analysis revealed that 96.50% of the genetic variation exists within the provenances. Low genetic distance and differentiation (Fst= 0.0199) were observed among cultivars from the four provenances. Ninety-nine cultivars were clustered into four clades, corresponding to the three ancestors of C. reticulata (diploid C. reticulata, C. pitardii, and C. saluenensis). The novel low-copy nuclear gene sequence markers developed in this study provide an effective tool for analyzing genetic diversity, phylogenetic relationships, and origination of C. reticulata cultivars.

Heritable human genome editing: correction, selection and treatment.

Heritable human genome editing (HHGE) to correct a nuclear gene sequence that would result in a serious genetic condition in a future child is presented as 'treatment' in various ethics and policy materials, and as morally preferable to the 'selection' practice of preimplantation genetic testing (PGT), which is subject to the disability critique. However, whether HHGE is 'treatment' for a future child, or another form of 'selection', or whether HHGE instead 'treats' prospective parents, are now central questions in the debate regarding its possible legalisation. This article argues that the idea of 'treatment' for a future child is largely a proxy for 'seriousness of purpose', intended to distinguish HHGE to avoid serious genetic conditions from less obviously justifiable uses; that HHGE is best understood, and morally justified, as a form of 'treatment' for prospective parents who strongly desire an unaffected genetically related child and who have no, or poor, options to achieve this; that HHGE would be morally permissible if consistent with that child's welfare; that legalisation is supportable with reference to the right to respect for private and family life under Article 8 of the European Convention on Human Rights; and that HHGE is morally distinguishable from PGT.

Dryopterisjinpingensis, a critically endangered diploid new species of Dryopteridaceae from Yunnan, China.

Dryopterisjinpingensis, a new species of diploid, sexually reproductive ferns of Dryopteridaceae from Yunnan, southwestern China, is described and illustrated. Morphologically, D.jinpingensis is similar to D.gaoligongensis but unique in elongated lanceolate laminae, sessile or subsessile pinna stalks, and overlapping membranous scales adnate to stipe base. Phylogenetic analyses based on both plastome and the nuclear AK1 gene sequences showed that D.jinpingensis is sister to D.gaoligongensis. A detailed taxonomic description with line drawings is provided, and its conservation status is evaluated to be critically endangered.

New insights into the molecular phylogeny, biogeographical history, and diversification of Amblyomma ticks (Acari: Ixodidae) based on mitogenomes and nuclear sequences.

Amblyomma is the third most diversified genus of Ixodidae that is distributed across the Indomalayan, Afrotropical, Australasian (IAA), Nearctic and Neotropical biogeographic ecoregions, reaching in the Neotropic its highest diversity. There have been hints in previously published phylogenetic trees from mitochondrial genome, nuclear rRNA, from combinations of both and morphology that the Australasian Amblyomma or the Australasian Amblyomma plus the Amblyomma species from the southern cone of South America, might be sister-group to the Amblyomma of the rest of the world. However, a stable phylogenetic framework of Amblyomma for a better understanding of the biogeographic patterns underpinning its diversification is lacking. We used genomic techniques to sequence complete and nearly complete mitochondrial genomes -ca. 15 kbp- as well as the nuclear ribosomal cluster -ca. 8 kbp- for 17 Amblyomma ticks in order to study the phylogeny and biogeographic pattern of the genus Amblyomma, with particular emphasis on the Neotropical region. The new genomic information generated here together with genomic information available on 43 ticks (22 other Amblyomma species and 21 other hard ticks-as outgroup-) were used to perform probabilistic methods of phylogenetic and biogeographic inferences and time-tree estimation using biogeographic dates. In the present paper, we present the strongest evidence yet that Australasian Amblyomma may indeed be the sister-group to the Amblyomma of the rest of the world (species that occur mainly in the Neotropical and Afrotropical zoogeographic regions). Our results showed that all Amblyomma subgenera (Cernyomma, Anastosiella, Xiphiastor, Adenopleura, Aponomma and Dermiomma) are not monophyletic, except for Walkeriana and Amblyomma. Likewise, our best biogeographic scenario supports the origin of Amblyomma and its posterior diversification in the southern hemisphere at 47.8 and 36.8 Mya, respectively. This diversification could be associated with the end of the connection of Australasia and Neotropical ecoregions by the Antarctic land bridge. Also, the biogeographic analyses let us see the colonization patterns of some neotropical Amblyomma species to the Nearctic. We found strong evidence that the main theater of diversification of Amblyomma was the southern hemisphere, potentially driven by the Antarctic Bridge's intermittent connection in the late Eocene. In addition, the subgeneric classification of Amblyomma lacks evolutionary support. Future studies using denser taxonomic sampling may lead to new findings on the phylogenetic relationships and biogeographic history of Amblyomma genus.