An ultraconserved element probe set for velvet worms (Onychophora).

Onychophora are cryptic, soil-dwelling invertebrates known for their biogeographic affinities, diversity of reproductive modes, close phylogenetic relationship to arthropods, and peculiar prey capture mechanism. The 216 valid species of Onychophora are grouped into two families - Peripatopsidae and Peripatidae - and apart from a few relationships among major lineages within these two families, a stable phylogenetic backbone for the phylum has yet to be resolved. This has hindered our understanding of onychophoran biogeographic patterns, evolutionary history, and systematics. Neopatida, the Neotropical clade of peripatids, has proved particularly difficult, with recalcitrant nodes and low resolution, potentially due to rapid radiation of the group during the Cretaceous. Previous studies have had to compromise between number of loci and number of taxa due to limitations of Sanger sequencing and phylotranscriptomics, respectively. Additionally, aspects of their genome size and structure have made molecular phylogenetics difficult and data matrices have been affected by missing data. To address these issues, we leveraged recent, published transcriptomes and the first high quality genome for the phylum and designed a high affinity ultraconserved element (UCE) probe set for Onychophora. This new probe set, consisting of âˆ¼ 20,000 probes that target 1,465 loci across both families, has high locus recovery and phylogenetic utility. Phylogenetic analyses recovered the monophyly of major clades of Onychophora and revealed a novel lineage from the Neotropics that challenges our current understanding of onychophoran biogeographic endemicity. This new resource could drastically increase the power of molecular datasets and potentially allow access to genomic scale data from archival museum specimens to further tackle the issues exasperating onychophoran systematics.

Ultraconserved elements-based phylogenomic systematics of the snake superfamily Elapoidea, with the description of a new Afro-Asian family.

The highly diverse snake superfamily Elapoidea is considered to be a classic example of ancient, rapid radiation. Such radiations are challenging to fully resolve phylogenetically, with the highly diverse Elapoidea a case in point. Previous attempts at inferring a phylogeny of elapoids produced highly incongruent estimates of their evolutionary relationships, often with very low statistical support. We sought to resolve this situation by sequencing over 4,500 ultraconserved element loci from multiple representatives of every elapoid family/subfamily level taxon and inferring their phylogenetic relationships with multiple methods. Concatenation and multispecies coalescent based species trees yielded largely congruent and well-supported topologies. Hypotheses of a hard polytomy were not retained for any deep branches. Our phylogenies recovered Cyclocoridae and Elapidae as diverging early within Elapoidea. The Afro-Malagasy radiation of elapoid snakes, classified as multiple subfamilies of an inclusive Lamprophiidae by some earlier authors, was found to be monophyletic in all analyses. The genus Micrelaps was consistently recovered as sister to Lamprophiidae. We establish a new family, Micrelapidae fam. nov., for Micrelaps and assign Brachyophis to this family based on cranial osteological synapomorphy. We estimate that Elapoidea originated in the early Eocene and rapidly diversified into all the major lineages during this epoch. Ecological opportunities presented by the post-Cretaceous-Paleogene mass extinction event may have promoted the explosive radiation of elapoid snakes.

Phylogenomics and body shape morphometrics reveal recent diversification in the goatfishes (Syngnatharia: Mullidae).

Clades of marine fishes exhibit many patterns of diversification, ranging from relatively constant throughout time to rapid changes in the rates of speciation and extinction. The goatfishes (Syngnatharia: Mullidae) are a family of marine, reef associated fishes with a relatively recent origin, distributed globally in tropical and temperate waters. Despite their abundance and economic importance, the goatfishes remain one of the few coral reef families for which the species level relationships have not been examined using genomic techniques. Here we use phylogenomic analysis of ultra-conserved elements (UCE) and exon data to resolve a well-supported, time-calibrated phylogeny for 72 species of goatfishes, supporting a recent crown age of the goatfishes at 21.9 million years ago. We used this framework to test hypotheses about the associations among body shape morphometrics, taxonomy, and phylogeny, as well as to explore relative diversification rates across the phylogeny. Body shape was strongly associated with generic-level taxonomy of goatfishes, with morphometric analyses showing evidence for high phylogenetic signal across all morphotypes. Rates of diversification in this clade reveal a recent sharp increase in lineage accumulation, with 92% of the goatfish species sampled across all clades and major body plans having originated in just the past 5 million years. We suggest that habitat diversity in the early Pliocene oceans and the generalist ecology of goatfishes are key factors in the unusual evolutionary tempo of the family Mullidae.

Systematics of the New World bats Eptesicus and Histiotus suggest trans-marine dispersal followed by Neotropical cryptic diversification.

Biodiversity can be boosted by colonization of new habitats such as remote islands and separated continents. Molecular studies have suggested that recently evolved organisms probably colonized already separated continents by dispersal, either via land bridge connections or crossing the ocean. Here we test the on-land and trans-marine dispersal hypotheses by evaluating possibilities of colonization routes over the Bering land bridge and across the Atlantic Ocean in the cosmopolitan bat genus Eptesicus (Chiroptera, Vespertilionidae). Previous molecular studies have found New World Eptesicus more closely related to Histiotus, a Neotropical endemic lineage with enlarged ears, than to Old World Eptesicus. However, phylogenetic relationships within the New World group remained unresolved and their evolutionary history was unclear. Here we studied the systematics of New World Eptesicus and Histiotus using extensive taxonomic and geographic sampling, and genomic data from thousands of ultra-conserved elements (UCEs). We estimated phylogenetic trees using concatenation and multispecies coalescent. All analyses supported four major New World clades and a novel topology where E. fuscus and Histiotus are sister clades that together diverged from two sister clades of Neotropical Eptesicus. Intra-clade divergence suggested cryptic diversity that has been concealed by morphological features, especially in the Neotropics where taxonomic re-evaluations are warranted. Molecular dating estimated that Old World and New World clades diverged around 17 million years ago followed by radiation of major New World clades in the mid-Miocene, when climatic changes might have facilitated global dispersal and radiation events. Biogeographic ancestral reconstruction supported the Neotropical origin of the New World clades, suggesting a trans-Atlantic colonization route from North Africa to the northern Neotropics. We highlight that trans-marine dispersal may be more prevalent than currently acknowledged and may be an important first step to global biodiversification.

Acute symptomatic seizures secondary to myelin oligodendrocyte glycoprotein antibody-associated disease.

OBJECTIVE: To report the clinical presentations and outcomes of patients with seizure and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). METHODS: We retrospectively reviewed the electronic medical records for clinical and paraclinical features among patients with seizures and MOG-IgG (immunoglobulin G) seropositivity. RESULTS: We identified 213 patients with MOG-IgG seropositivity who fulfilled criteria for MOGAD. Seizures attributed to central nervous system (CNS) autoimmunity were observed in 10% of patients (n = 23: 19 children, 4 adults). The majority (n = 19, 83%) had pediatric disease onset. Focal motor seizures were the most common seizure semiology (16/23; 70%). Focal to bilateral tonic-clonic seizures were present in 12 patients (53%), and 3 patients (13%) developed status epilepticus. All patients had features of encephalitis at onset of seizures. Cerebral cortical encephalitis (CCE) was the most common radiological finding (10 unilateral and 5 bilateral cases). Eight of 23 patients (35%) had only CCE, six of 23 patients (26%) had only acute disseminated encephalomyelitis (ADEM), and seven of 23 patients (30%) had features of both. Fifteen patients (65%) had leptomeningeal enhancement. Three patients (13%) had coexistence of N-methyl-d-aspartate receptor (NMDAR) IgG. Only 3 of 23 patients (13%) developed drug- resistant epilepsy. Although the majority had MOGAD relapses (14/23, 60%) had only 5 of 23 patients had recurrence of episodes of encephalitis with associated seizures. Twenty-one of 23 patients (91%) had seizure freedom at last follow-up. SIGNIFICANCE: MOG-IgG evaluation should be considered in patients who present with encephalitis and focal motor and/or focal to bilateral tonic-clonic seizures, especially pediatric patients with magnetic resonance imaging (MRI) brain findings consistent with CCE, ADEM, or other MOGAD presentations. The majority of these seizures are self-limited and do not require maintenance/chronic antiseizure medications. Although seizure recurrence is uncommon, many patients have MOGAD relapses in the form of encephalitis and optic neuritis.

Diverse phylogenomic datasets uncover a concordant scenario of laurasiatherian interordinal relationships.

Resolving the interordinal relationships in the mammalian superorder Laurasiatheria has been among the most intractable problems in higher-level mammalian systematics, with many conflicting hypotheses having been proposed. The present study collected three different sources of genome-scale data with comprehensive taxon sampling of laurasiatherian species, including two protein-coding datasets (4,186 protein-coding genes for an amino acid dataset comprising 2,761,247 amino acid residues and a nucleotide dataset comprising 5,516,340 nucleotides from 1st and 2nd codon positions), an intronic dataset (1,210 introns comprising 1,162,723 nucleotides) and an ultraconserved elements (UCEs) dataset (1,246 UCEs comprising 1,946,472 nucleotides) from 40 species representing all six laurasiatherian orders and 7 non-laurasiatherian outgroups. Remarkably, phylogenetic trees reconstructed with the four datasets using different tree-building methods (RAxML, FastTree, ASTRAL and MP-EST) all supported the relationship (Eulipotyphla, (Chiroptera, ((Carnivora, Pholidota), (Cetartiodactyla, Perissodactyla)))). We find a resolution of interordinal relationships of Laurasiatheria among all types of markers used in the present study, and the likelihood ratio tests for tree comparisons confirmed that the present tree topology is the optimal hypothesis compared to other examined hypotheses. Jackknifing subsampling analyses demonstrate that the results of laurasiatherian tree reconstruction varied with the number of loci and ordinal representatives used, which are likely the two main contributors to phylogenetic disagreements of Laurasiatheria seen in previous studies. Our study provides significant insight into laurasiatherian evolution, and moreover, an important methodological strategy and reference for resolving phylogenies of adaptive radiation, which have been a long-standing challenge in the field of phylogenetics.

Ultraconserved element bait set for trypanosomatida target enrichment and phylogenetics.

Lack of knowledge of taxonomic biodiversity and reliable genetic markers in Trypanosomatidae limit our understanding of their phylogenetic relationships. Ultraconserved elements (UCEs) have improved phylogenetic analyses and inferences in many vertebrate and invertebrate taxa. However, it is unknown whether protozoans have these markers, their abundance, and if these could be reliably used for phylogenetics. In this study I design a target enrichment bait set for UCE loci for this group. In silico testing showed good loci recovery rates across 63 taxa and produced consistent, highly supported phylogenetic trees. This bait set adds a new resource of useful genetic markers for Trypanosomatidae phylogenetics.

A phylogenomic framework for pelagiarian fishes (Acanthomorpha: Percomorpha) highlights mosaic radiation in the open ocean.

The fish clade Pelagiaria, which includes tunas as its most famous members, evolved remarkable morphological and ecological variety in a setting not generally considered conducive to diversification: the open ocean. Relationships within Pelagiaria have proven elusive due to short internodes subtending major lineages suggestive of rapid early divergences. Using a novel sequence dataset of over 1000 ultraconserved DNA elements (UCEs) for 94 of the 286 species of Pelagiaria (more than 70% of genera), we provide a time-calibrated phylogeny for this widely distributed clade. Some inferred relationships have clear precedents (e.g. the monophyly of 'core' Stromateoidei, and a clade comprising 'Gempylidae' and Trichiuridae), but others are unexpected despite strong support (e.g. Chiasmodontidae + Tetragonurus). Relaxed molecular clock analysis using node-based fossil calibrations estimates a latest Cretaceous origin for Pelagiaria, with crown-group families restricted to the Cenozoic. Estimated mean speciation rates decline from the origin of the group in the latest Cretaceous, although credible intervals for root and tip rates are broad and overlap in most cases, and there is higher-than-expected partitioning of body shape diversity (measured as fineness ratio) between clades concentrated during the Palaeocene-Eocene. By contrast, more direct measures of ecology show either no substantial deviation from a null model of diversification (diet) or patterns consistent with evolutionary constraint or high rates of recent change (depth habitat). Collectively, these results indicate a mosaic model of diversification. Pelagiarians show high morphological disparity and modest species richness compared to better-studied fish radiations in contrasting environments. However, this pattern is also apparent in other clades in open-ocean or deep-sea habitats, and suggests that comparative study of such groups might provide a more inclusive model of the evolution of diversity in fishes.

Post K-Pg diversification of the mammalian order Eulipotyphla as suggested by phylogenomic analyses of ultra-conserved elements.

The origin of the mammalian order Eulipotyphla has been debated intensively with arguments around whether they began diversifying before or after the Cretaceous-Palaeogene (K-Pg) boundary at 66 Ma. Here, we used an in-solution nucleotide capture method and next generation DNA sequencing to determine the sequence of hundreds of ultra-conserved elements (UCEs), and conducted phylogenomic and molecular dating analyses for the four extant eulipotyphlan lineages-Erinaceidae, Solenodontidae, Soricidae, and Talpidae. Concatenated maximum-likelihood analyses with single or partitioned models and a coalescent species-tree analysis showed that divergences among the four major eulipotyphlan lineages occurred within a short period of evolutionary time, but did not resolve the interrelationships among them. Alternative suboptimal phylogenetic hypotheses received consistently the same amount of support from different UCE loci, and were not significantly different from the maximum likelihood tree topology, suggesting the prevalence of stochastic lineage sorting. Molecular dating analyses that incorporated among-lineage evolutionary rate differences supported a scenario where the four eulipotyphlan families diversified between 57.8 and 63.2 Ma. Given short branch lengths with low support values, traces of rampant genome-wide stochastic lineage sorting, and post K-Pg diversification, we concluded that the crown eulipotyphlan lineages arose through a rapid diversification after the K-Pg boundary when novel niches were created by the mass extinction of species.

Evidence for mtDNA capture in the jacamar Galbula leucogastra/chalcothorax species-complex and insights on the evolution of white-sand ecosystems in the Amazon basin.

Jacamar species occur throughout Amazonia, with most species occupying forested habitats. One species-complex, Galbula leucogastra/chalcothorax, is associated to white sand ecosystems (WSE). Previous studies of WSE bird species recovered shallow genetic structure in mtDNA coupled with signs of gene flow among WSE patches. Here, we characterize diversification of the G. leucogastra/chalcothorax species-complex with dense sampling across its distribution using mitochondrial and genomic (Ultraconserved Elements, UCEs) DNA sequences. We performed concatenated likelihood and Bayesian analysis, as well as a species-tree analysis using ∗BEAST, to establish the phylogenetic relationships among populations. The mtDNA results recovered at least six geographically-structured lineages, with G. chalcothorax embedded within lineages of G. leucogastra. In contrast, both concatenated and species-tree analyses of UCE data recovered G. chalcothorax as sister to all G. leucogastra lineages. We hypothesize that the mitochondrial genome of one of the G. leucogastra lineage (Madeira) was captured into G. chalcothorax in the past. We discuss how WSE evolution and the coevolution of mtDNA and nuclear genes might have played a role in this apparently rare event.

Detecting the Anomaly Zone in Species Trees and Evidence for a Misleading Signal in Higher-Level Skink Phylogeny (Squamata: Scincidae).

The anomaly zone, defined by the presence of gene tree topologies that are more probable than the true species tree, presents a major challenge to the accurate resolution of many parts of the Tree of Life. This discrepancy can result from consecutive rapid speciation events in the species tree. Similar to the problem of long-branch attraction, including more data via loci concatenation will only reinforce the support for the incorrect species tree. Empirical phylogenetic studies often employ coalescent-based species tree methods to avoid the anomaly zone, but to this point these studies have not had a method for providing any direct evidence that the species tree is actually in the anomaly zone. In this study, we use 16 species of lizards in the family Scincidae to investigate whether nodes that are difficult to resolve place the species tree within the anomaly zone. We analyze new phylogenomic data (429 loci), using both concatenation and coalescent-based species tree estimation, to locate conflicting topological signal. We then use the unifying principle of the anomaly zone, together with estimates of ancestral population sizes and species persistence times, to determine whether the observed phylogenetic conflict is a result of the anomaly zone. We identify at least three regions of the Scincidae phylogeny that provide demographic signatures consistent with the anomaly zone, and this new information helps reconcile the phylogenetic conflict in previously published studies on these lizards. The anomaly zone presents a real problem in phylogenetics, and our new framework for identifying anomalous relationships will help empiricists leverage their resources appropriately for investigating and overcoming this challenge.

Phylogenomic analysis of carangimorph fishes reveals flatfish asymmetry arose in a blink of the evolutionary eye.

BACKGROUND: Flatfish cranial asymmetry represents one of the most remarkable morphological innovations among vertebrates, and has fueled vigorous debate on the manner and rate at which strikingly divergent phenotypes evolve. A surprising result of many recent molecular phylogenetic studies is the lack of support for flatfish monophyly, where increasingly larger DNA datasets of up to 23 loci have either yielded a weakly supported flatfish clade or indicated the group is polyphyletic. Lack of resolution for flatfish relationships has been attributed to analytical limitations for dealing with processes such as nucleotide non-stationarity and incomplete lineage sorting (ILS). We tackle this phylogenetic problem using a sequence dataset comprising more than 1,000 ultraconserved DNA element (UCE) loci covering 45 carangimorphs, the broader clade containing flatfishes and several other specialized lineages such as remoras, billfishes, and archerfishes. RESULTS: We present a phylogeny based on UCE loci that unequivocally supports flatfish monophyly and a single origin of asymmetry. We document similar levels of discordance among UCE loci as in previous, smaller molecular datasets. However, relationships among flatfishes and carangimorphs recovered from multilocus concatenated and species tree analyses of our data are robust to the analytical framework applied and size of data matrix used. By integrating the UCE data with a rich fossil record, we find that the most distinctive carangimorph bodyplans arose rapidly during the Paleogene (66.0-23.03 Ma). Flatfish asymmetry, for example, likely evolved over an interval of no more than 2.97 million years. CONCLUSIONS: The longstanding uncertainty in phylogenetic hypotheses for flatfishes and their carangimorph relatives highlights the limitations of smaller molecular datasets when applied to successive, rapid divergences. Here, we recovered significant support for flatfish monophyly and relationships among carangimorphs through analysis of over 1,000 UCE loci. The resulting time-calibrated phylogeny points to phenotypic divergence early within carangimorph history that broadly matches with the predictions of adaptive models of lineage diversification.

Phylogenomic analyses reveal novel relationships among snake families.

Snakes are a diverse and important group of vertebrates. However, relationships among the major groups of snakes have remained highly uncertain, with recent studies hypothesizing very different (and typically weakly supported) relationships. Here, we address family-level snake relationships with new phylogenomic data from 3776 nuclear loci from ultraconserved elements (1.40million aligned base pairs, 52% missing data overall) sampled from 29 snake species that together represent almost all families, a dataset ∼100 times larger than used in previous studies. We found relatively strong support from species-tree analyses (NJst) for most relationships, including three largely novel clades: (1) a clade uniting the boas, pythons and their relatives, (2) a clade placing cylindrophiids and uropeltids with this clade, and (3) a clade uniting bolyeriids (Round Island boas) with pythonids and their relatives (xenopeltids and loxocemids). Relationships among families of advanced snakes (caenophidians) were also strongly supported. The results show the potential for phylogenomic analyses to resolve difficult groups, but also show a surprising sensitivity of the analyses to the inclusion or exclusion of outgroups.

Roles of the nucleolus in the CAG RNA-mediated toxicity.

The nucleolus is a subnuclear compartment within the cell nucleus that serves as the site for ribosomal RNA (rRNA) transcription and the assembly of ribosome subunits. Apart from its classical role in ribosomal biogenesis, a number of cellular regulatory roles have recently been assigned to the nucleolus, including governing the induction of apoptosis. "Nucleolar stress" is a term that is used to describe a signaling pathway through which the nucleolus communicates with other subcellular compartments, including the mitochondria, to induce apoptosis. It is an effective mechanism for eliminating cells that are incapable of performing protein synthesis efficiently due to ribosome biogenesis defects. The down-regulation of rRNA transcription is a common cause of nucleolar function disruption that subsequently triggers nucleolar stress, and has been associated with the pathogenesis of neurological disorders such as spinocerebellar ataxias (SCAs) and Huntington's diseases (HD). This article discusses recent advances in mechanistic studies of how expanded CAG trinucleotide repeat RNA transcripts trigger nucleolar stress in SCAs, HD and other trinucleotide repeat disorders. This article is part of a Special Issue entitled: Role of the Nucleolus in Human Disease.

Skimming genomes for systematics and DNA barcodes of corals.

Numerous genomic methods developed over the past two decades have enabled the discovery and extraction of orthologous loci to help resolve phylogenetic relationships across various taxa and scales. Genome skimming (or low-coverage genome sequencing) is a promising method to not only extract high-copy loci but also 100s to 1000s of phylogenetically informative nuclear loci (e.g., ultraconserved elements [UCEs] and exons) from contemporary and museum samples. The subphylum Anthozoa, including important ecosystem engineers (e.g., stony corals, black corals, anemones, and octocorals) in the marine environment, is in critical need of phylogenetic resolution and thus might benefit from a genome-skimming approach. We conducted genome skimming on 242 anthozoan corals collected from 1886 to 2022. Using existing target-capture baitsets, we bioinformatically obtained UCEs and exons from the genome-skimming data and incorporated them with data from previously published target-capture studies. The mean number of UCE and exon loci extracted from the genome skimming data was 1837 ± 662 SD for octocorals and 1379 ± 476 SD loci for hexacorals. Phylogenetic relationships were well resolved within each class. A mean of 1422 ± 720 loci was obtained from the historical specimens, with 1253 loci recovered from the oldest specimen collected in 1886. We also obtained partial to whole mitogenomes and nuclear rRNA genes from >95% of samples. Bioinformatically pulling UCEs, exons, mitochondrial genomes, and nuclear rRNA genes from genome skimming data is a viable and low-cost option for phylogenetic studies. This approach can be used to review and support taxonomic revisions and reconstruct evolutionary histories, including historical museum and type specimens.

Phylogeny of Rhynchium and Its Related Genera (Hymenoptera: Eumeninae) Based on Universal Single-Copy Orthologs and Ultraconserved Elements.

The subfamily Eumeninae is a large group of fierce predatory insects that prey mainly on the larvae of Lepidoptera pests. Because of the highly similar morphologies of the genus Rhynchium and its related genera in the subfamily, including Rhynchium Spinola, Allorhynchium van der Vecht, Anterhynchium de Saussure, Pararrhynchium de Saussure, it is essential to delineate their relationships. A previous phylogenetic analysis based on mitochondrial genomes suggested the inconsistent relationships of these genera under traditional classification based on morphological characters. In this study, we first used single-copy orthologs [USCO] and ultraconserved elements [UCE] extracted from 10 newly sequenced low-coverage whole genomes to resolve the phylogenetic relationships of the above genera. The newly sequenced genomes are 152.99 Mb to 211.49 Mb in size with high completeness (BUSCO complete: 91.5-95.6%) and G + C content (36.31-38.76%). Based on extracted 5811 USCOs and 2312 UCEs, the phylogenetic relationships of Rhynchium and its related genera were: ((Allorhynchium + Lissodynerus) + (Pararrhynchium + (Anterhynchium + (Dirhynchium + Rhynchium)))), which was consistent with the mitochondrial genome results. The results supported the genus Rhynchium as monophyletic, whereas Anterhynchium was recovered as paraphyletic, with Anterhynchium (Dirhynchium) as a sister to Rhynchium and hence deserving generic status; In addition, in the genus Pararrhynchium, P. septemfasciatus feanus and P. venkataramani were separated, not clustered on a branch, just as P. septemfasciatus feanus was not together with P. striatum based on mitochondrial genomes. Since Lissodynerus septemfasciatus, the type species of the genus Lissodynerus, was transferred to Pararrhynchium, it is considered that the genus Lissodynerus should be restituted as a valid genus, not a synonym of Pararrhynchium.

Phylogenomics and Diversification of the Schistosomatidae Based on Targeted Sequence Capture of Ultra-Conserved Elements.

Schistosomatidae Stiles and Hassall 1898 is a medically significant family of digenetic trematodes (Trematoda: Digenea), members of which infect mammals or birds as definitive hosts and aquatic or amphibious gastropods as intermediate hosts. Currently, there are 17 named genera, for many of which evolutionary interrelationships remain unresolved. The lack of a resolved phylogeny has encumbered our understanding of schistosomatid evolution, specifically patterns of host-use and the role of host-switching in diversification. Here, we used targeted sequence capture of ultra-conserved elements (UCEs) from representatives of 13 of the 17 named genera and 11 undescribed lineages that are presumed to represent either novel genera or species to generate a phylogenomic dataset for the estimation of schistosomatid interrelationships. This study represents the largest phylogenetic effort within the Schistosomatidae in both the number of loci and breadth of taxon sampling. We present a near-comprehensive family-level phylogeny providing resolution to several clades of long-standing uncertainty within Schistosomatidae, including resolution for the placement of the North American mammalian schistosomes, implying a second separate capture of mammalian hosts. Additionally, we present evidence for the placement of Macrobilharzia at the base of the Schistosoma + Bivitellobilharzia radiation. Patterns of definitive and intermediate host use and a strong role for intermediate host-switching are discussed relative to schistosomatid diversification.

New alignment-based sequence extraction software (ALiBaSeq) and its utility for deep level phylogenetics.

Despite many bioinformatic solutions for analyzing sequencing data, few options exist for targeted sequence retrieval from whole genomic sequencing (WGS) data with the ultimate goal of generating a phylogeny. Available tools especially struggle at deep phylogenetic levels and necessitate amino-acid space searches, which may increase rates of false positive results. Many tools are also difficult to install and may lack adequate user resources. Here, we describe a program that uses freely available similarity search tools to find homologs in assembled WGS data with unparalleled freedom to modify parameters. We evaluate its performance compared to other commonly used bioinformatics tools on two divergent insect species (>200 My) for which annotated genomes exist, and on one large set each of highly conserved and more variable loci. Our software is capable of retrieving orthologs from well-curated or unannotated, low or high depth shotgun, and target capture assemblies as well or better than other software as assessed by recovering the most genes with maximal coverage and with a low rate of false positives throughout all datasets. When assessing this combination of criteria, ALiBaSeq is frequently the best evaluated tool for gathering the most comprehensive and accurate phylogenetic alignments on all types of data tested. The software (implemented in Python), tutorials, and manual are freely available at https://github.com/AlexKnyshov/alibaseq.

New approaches to species delimitation and population structure of anthozoans: Two case studies of octocorals using ultraconserved elements and exons.

As coral populations decline worldwide in the face of ongoing environmental change, documenting their distribution, diversity and conservation status is now more imperative than ever. Accurate delimitation and identification of species is a critical first step. This task, however, is not trivial as morphological variation and slowly evolving molecular markers confound species identification. New approaches to species delimitation in corals are needed to overcome these challenges. Here, we test whether target enrichment of ultraconserved elements (UCEs) and exons can be used for delimiting species boundaries and population structure within species of corals by focusing on two octocoral genera, Alcyonium and Sinularia, as exemplary case studies. We designed an updated bait set (29,181 baits) to target-capture 3,023 UCE and exon loci, recovering a mean of 1,910 ± 168 SD per sample with a mean length of 1,055 ± 208 bp. Similar numbers of loci were recovered from Sinularia (1,946 ± 227 SD) and Alcyonium (1,863 ± 177 SD). Species-level phylogenies were highly supported for both genera. Clustering methods based on filtered single nucleotide polymorphisms delimited species and populations that are congruent with previous allozyme, DNA barcoding, reproductive and ecological data for Alcyonium, and offered further evidence of hybridization among species. For Sinularia, results were congruent with those obtained from a previous study using restriction site associated DNA sequencing. Both case studies demonstrate the utility of target-enrichment of UCEs and exons to address a wide range of evolutionary and taxonomic questions across deep to shallow timescales in corals.

The upper eyelid levator weakening procedure for the correction of severe cicatricial entropion caused by trachoma.

BACKGROUND: Trachoma-induced upper eyelid cicatricial entropion (UCE) is a common and challenging eyelid disease. Surgeons have developed various surgical techniques to address UCE in the world. However, there are few reports about surgery for Chinese patients. Our study aims to evaluate the esthetic and functional outcomes of correction of trachoma-induced UCE using upper eyelid levator weakening combined with tarsotomy and an anterior lamella recession procedure in China. METHODS: A retrospective non-comparative study was performed in the Ophthalmology Department of Second Affiliated Hospital of Guangzhou University of Chinese Medicine from January 2017 to December 2019. Thirty-six patients (56 eyelids) with severe UCE caused by trachoma, defined as shortening and retraction of the posterior lamella, were collected. Upper eyelid levator weakening combined with tarsotomy and an anterior lamella recession procedure was done on all patients. The mean follow-up time was 11.6±2.71 months (range, 6-24 months). RESULTS: Among the patients, 48 eyelids (85.7%) achieved complete success. Recurrence was observed in 4 eyelids (7.1%). No other severe complications occurred. CONCLUSIONS: This case series showed that upper eyelid levator weakening combined with tarsotomy and an anterior lamella recession procedure is a safe and effective treatment for severe trachoma-induced UCE in Chinese patients.