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In this study, we describe Zavrelia parapentatoma sp. nov. based on specimens collected near a cattail marsh in Michigan, USA. At first glance, the new species resembles Zavrelia pentatoma Kieffer & Bause, 1913 closely. However, a detailed morphological and molecular assessment revealed the differences. Morphologically the two species can be separated mainly based on the shape and pattern of long spinulae between long anal crests of adult males and setal patterns on the pupal abdomen. Larvae of both species also have some subtle morphological differences that are discussed in this study. Our molecular analysis of cytochrome oxidase (COI) genes and methods for delimiting species further supported the presence of a new species. In this study, we describe all the life stages, provide life history observations for this new species, and provide keys to adult males and immatures of the genus Zavrelia.

Conservation and management professionals often work across jurisdictional boundaries to identify broad ecological patterns. These collaborations help to protect populations whose distributions span political borders. One common limitation to multijurisdictional collaboration is consistency in data recording and reporting. This limitation can impact genetic research, which relies on data about specific markers in an organism's genome. Incomplete overlap of markers between separate studies can prevent direct comparisons of results. Standardized marker panels can reduce the impact of this issue and provide a common starting place for new research. Genotyping-in-thousands (GTSeq) is one approach used to create standardized marker panels for nonmodel organisms. Here, we describe the development, optimization, and early assessments of a new GTSeq panel for use with walleye ( Sander vitreus ) from the Great Lakes region of North America. High genome-coverage sequencing conducted using RAD capture provided genotypes for thousands of single nucleotide polymorphisms (SNPs). From these markers, SNP and microhaplotype markers were chosen, which were informative for genetic stock identification (GSI) and kinship analysis. The final GTSeq panel contained 500 markers, including 197 microhaplotypes and 303 SNPs. Leave-one-out GSI simulations indicated that GSI accuracy should be greater than 80% in most jurisdictions. The false-positive rates of parent-offspring and full-sibling kinship identification were found to be low. Finally, genotypes could be consistently scored among separate sequencing runs >94% of the time. Results indicate that the GTSeq panel that we developed should perform well for multijurisdictional walleye research throughout the Great Lakes region., (© 2022 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Groups of sympatric taxa with low interspecific genetic differentiation, but considerable ecological differences, offer great opportunities to study the dynamics of divergence and speciation. This is the case of ciscoes (Coregonus spp.) in the Laurentian Great Lakes, which are characterized by a complex evolutionary history and are commonly described as having undergone an adaptive radiation. In this study, morphometrics, stable isotopes and transcriptome sequencing were used to study the relationships within the Coregonus artedi complex in western Lake Superior. We observed general concordance for morphological, ecological and genomic variation, but the last was more taxonomically informative as it showed less overlap among species in multivariate space. Low levels of genetic differentiation were observed between individuals morphologically identified as Coregonus hoyi and C. zenithicus, which could be evidence of incomplete lineage sorting or recent hybridization between the two groups. Transcriptome-based single nucleotide polymorphisms exhibited significant divergence for genes associated with vision, development, metabolism and immunity among species that occupy different habitats. This study highlights the importance of using an integrative approach when studying groups of taxa with a complex evolutionary history, as individual-level analyses of multiple independent data sets can provide a clearer picture of the patterns and processes associated with the origins of biodiversity., (© 2022 John Wiley & Sons Ltd. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)

Whole-genome duplication (WGD) is hypothesized to be an important evolutionary mechanism that can facilitate adaptation and speciation. Genomes that exist in states of both diploidy and residual tetraploidy are of particular interest, as mechanisms that maintain the ploidy mosaic after WGD may provide important insights into evolutionary processes. The Salmonidae family exhibits residual tetraploidy, and this, combined with the evolutionary diversity formed after an ancestral autotetraploidization event, makes this group a useful study system. In this study, we generate a novel linkage map for cisco ( Coregonus artedi ), an economically and culturally important fish in North America and a member of the subfamily Coregoninae, which previously lacked a high-density haploid linkage map. We also conduct comparative genomic analyses to refine our understanding of chromosomal fusion/fission history across salmonids. To facilitate this comparative approach, we use the naming strategy of protokaryotype identifiers (PKs) to associate duplicated chromosomes to their putative ancestral state. The female linkage map for cisco contains 20,292 loci, 3,225 of which are likely within residually tetraploid regions. Comparative genomic analyses revealed that patterns of residual tetrasomy are generally conserved across species, although interspecific variation persists. To determine the broad-scale retention of residual tetrasomy across the salmonids, we analyze sequence similarity of currently available genomes and find evidence of residual tetrasomy in seven of the eight chromosomes that have been previously hypothesized to show this pattern. This interspecific variation in extent of rediploidization may have important implications for understanding salmonid evolutionary histories and informing future conservation efforts., (Copyright © 2020 Blumstein et al.)

Effective resource management depends on our ability to partition diversity into biologically meaningful units. Recent evolutionary divergence, however, can often lead to ambiguity in morphological and genetic differentiation, complicating the delineation of valid conservation units. Such is the case with the "coregonine problem," where recent postglacial radiations of coregonines into lacustrine habitats resulted in the evolution of numerous species flocks, often with ambiguous taxonomy. The application of genomics methods is beginning to shed light on this problem and the evolutionary mechanisms underlying divergence in these ecologically and economically important fishes. Here, we used restriction site-associated DNA (RAD) sequencing to examine genetic diversity and differentiation among sympatric forms in the Coregonus artedi complex in the Apostle Islands of Lake Superior, the largest lake in the Laurentian Great Lakes. Using 29,068 SNPs, we were able to clearly distinguish among the three most common forms for the first time, as well as identify putative hybrids and potentially misidentified specimens. Population assignment rates for these forms using our RAD data were 93%-100% with the only mis-assignments arising from putative hybrids, an improvement from 62% to 77% using microsatellites. Estimates of pairwise differentiation ( F ST : 0.045-0.056) were large given the detection of hybrids, suggesting that reduced fitness of hybrid individuals may be a potential mechanism for the maintenance of differentiation. We also used a newly built C. artedi linkage map to look for islands of genetic divergence among forms and found widespread differentiation across the genome, a pattern indicative of long-term drift, suggesting that these forms have been reproductively isolated for a substantial amount of time. The results of this study provide valuable information that can be applied to develop well-informed management strategies and stress the importance of re-evaluating conservation units with genomic tools to ensure they accurately reflect species diversity., Competing Interests: None declared., (© 2020 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd.)

Reduced representation (RRL) sequencing approaches (e.g., RADSeq, genotyping by sequencing) require decisions about how much to invest in genome coverage and sequencing depth, as well as choices of values for adjustable bioinformatics parameters. To empirically explore the importance of these "simple" methodological decisions, we generated two independent sequencing libraries for the same 142 individual lake whitefish (Coregonus clupeaformis) using a nextRAD RRL approach: (1) a larger number of loci at low sequencing depth based on a 9mer (library A); and (2) fewer loci at higher sequencing depth based on a 10mer (library B). The fish were selected from populations with different levels of expected genetic subdivision. Each library was analyzed using the STACKS pipeline followed by three types of population structure assessment (FST, DAPC and ADMIXTURE) with iterative increases in the stringency of sequencing depth and missing data requirements, as well as more specific a priori population maps. Library B was always able to resolve strong population differentiation in all three types of assessment regardless of the selected parameters, largely due to retention of more loci in analyses. In contrast, library A produced more variable results; increasing the minimum sequencing depth threshold (-m) resulted in a reduced number of retained loci, and therefore lost resolution at high -m values for FST and ADMIXTURE, but not DAPC. When detecting fine population differentiation, the population map influenced the number of loci and missing data, which generated artefacts in all downstream analyses tested. Similarly, when examining fine scale population subdivision, library B was robust to changing parameters but library A lost resolution depending on the parameter set. We used library B to examine actual subdivision in our study populations. All three types of analysis found complete subdivision among populations in Lake Huron, ON and Dore Lake, SK, Canada using 10,640 SNP loci. Weak population subdivision was detected in Lake Huron with fish from sites in the north-west, Search Bay, North Point and Hammond Bay, showing slight differentiation. Overall, we show that apparently simple decisions about library construction and bioinformatics parameters can have important impacts on the interpretation of population subdivision. Although potentially more costly on a per-locus basis, early investment in striking a balance between the number of loci and sequencing effort is well worth the reduced genomic coverage for population genetics studies. More conservative stringency settings on STACKS parameters lead to a final dataset that was more consistent and robust when examining both weak and strong population differentiation. Overall, we recommend that researchers approach "simple" methodological decisions with caution, especially when working on non-model species for the first time., Competing Interests: The authors have declared that no competing interests exist.

Recent assessments indicate the emergence of naturally produced lake trout (Salvelinus namaycush) recruitment throughout Lake Huron in the North American Laurentian Great Lakes (>50% of fish <7 years). Because naturally produced fish derived from different stocked hatchery strains are unmarked, managers cannot distinguish strains contributing to natural recruitment. We used 15 microsatellite loci to identify strains of naturally produced lake trout (N = 1567) collected in assessment fisheries during early (2002-2004) and late (2009-2012) sampling periods. Individuals from 13 American and Canadian hatchery strains (N = 1143) were genotyped to develop standardized baseline information. Strain contributions were estimated using a Bayesian inferential approach. Deviance information criteria were used to compare models evaluating strain contributions at different spatial and temporal scales. The best performing models were the most complex models, suggesting that hatchery strain contributions to naturally produced lake trout varied spatially among management districts and temporally between time periods. Contributions of Seneca strain lake trout were consistently high across most management districts, with contributions increasing from early to late time periods (estimates ranged from 52% to 94% for the late period across 8 of 9 districts). Strain contributions deviated from expectations based on historical stocking levels, indicating strains differed with respect to survival, reproductive success, and/or dispersal. Knowledge of recruitment levels of strains stocked in different management districts, and how strain-specific recruitment varies temporally, spatially, and as a function of local or regional stocking is important to prioritize strains for future stocking and management of the transition process from primarily hatchery to naturally produced stocks.

Background: We report on a unique audit of seven sonographers self-reporting high visualization rates of normal postmenopausal ovaries in the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS).   This audit was ordered by the trial's Ultrasound Management Subcommittee after an initiative taken in 2008 to improve the quality of scanning and the subsequent increase in the number of sonographers claiming very high ovary visualisation rates. Methods: Seven sonographers reporting high rates (>89%) of visualizing normal postmenopausal ovaries in examinations performed between 1 st January and 31 st December 2008 were identified. Eight experts in gynaecological scanning reviewed a random selection of exams performed by these sonographers and assessed whether visualization of both ovaries could be confirmed (cVR-Both) in the examinations. A random effects bivariate probit model was fitted to analyse the results.   Results: The eight experts reviewed images from 357 examinations performed on 349 postmenopausal women (mean age 60.0 years, range 50.2-73.3) by the seven sonographers. The mean cVR-Both obtained from the model for these sonographers was 67.2% with a range of 47.6-86.5% (95%CI 63.9-70.5%). The range of cVR-Both between the experts was 47.3-88.3% and the intra-class correlation coefficient (ICC) for left and right ovary confirmation was 0.39.     Conclusions: The audit suggests that self-reported visualization of postmenopausal ovaries is unreliable, as visualisation of both ovaries could not be confirmed in almost a third of examinations. The agreement for visualization of both ovaries based on review of a static image between experts and sonographers and between expert reviewers alone was only moderate. Further research is needed to develop reliable Quality Control metrics for transvaginal ultrasound., Competing Interests: Competing interests: UM has stock ownership and research funding from Abcodia. She has received grants from Medical Research Council (MRC), Cancer Research UK (CR UK), the National Institute for Health Research (NIHR), and The Eve Appeal (TEA). IJJ reports personal fees from and stock ownership in Abcodia as the non-executive director and consultant. He reports personal fees from Women’s Health Specialists as the director. He has a patent for the Risk of Ovarian Cancer algorithm and an institutional licence to Abcodia with royalty agreement. He is a trustee (2012–14) and Emeritus Trustee (2015 to present) for The Eve Appeal. He has received grants from the MRC, CR UK, NIHR, and TEA. The remaining authors declare no competing interests.

Objective: To determine if an extended perioperative course of corticosteroids will improve pain control following transoral robotic surgery (TORS)., Study Design: Randomized, double-blind, placebo-controlled trial., Methods: Patients undergoing TORS for initial treatment of oropharyngeal squamous cell carcinoma received a single intraoperative dose of 10-mg dexamethasone and then were randomized to receive 8-mg dexamethasone every 8 hours, or placebo, for up to 4 days after surgery. Pain, measured by visual analog scale (VAS), was the primary outcome measure. Secondary outcome measures included length of stay, dysphagia assessments, and complications., Results: VAS pain scores were similar between steroid and placebo cohorts on postoperative day (POD) 1, 2, and 7 through 21, although they significantly improved in the steroid cohort on POD 3. The steroid cohort also demonstrated a decreased hospital length of stay (median 1 day) and improvement in diet consistency, as measured by the performance status scale on POD 7 through 21. There was no difference in complications between the steroid and placebo cohorts., Conclusion: Extended perioperative corticosteroids after TORS is safe and may allow earlier improvement in diet consistency and decreased length of hospital stay, although postoperative pain appears minimally affected., Level of Evidence: 1b. Laryngoscope, 127:2558-2564, 2017., (© 2017 The American Laryngological, Rhinological and Otological Society, Inc.)

Background: Surgical access to metastases in the retropharyngeal lymph nodes (RPLNs) could be difficult. Transoral robotic surgery (TORS) can be utilized to access RPLNs. The purpose of this study was to describe a TORS approach to RPLN dissection., Methods: A case series of patients undergoing RPLN dissection by TORS was conducted and compared to matched controls (1:2)., Results: Twelve patients underwent robotic RPLN dissection. Median age was 63 years (range, 43-73 years). Pathology was oropharyngeal squamous cell carcinoma (SCC) in 9 patients and papillary thyroid cancer (PTC) in 3 patients. The feeding tube dependence duration was 12 days (range, 1-46 days) on average. Complications occurred in 8 patients (66%); most commonly, aspiration pneumonitis in 6 patients. In comparison to the matched controls (24), there was no difference in length of stay or feeding tube dependence. Complications were higher in patients with oropharyngeal SCC., Conclusion: TORS is feasible for accessing RPLNs. The procedure is well tolerated in patients with PTC; whereas patients with oropharyngeal SCC are at increased risk of complications. © 2015 Wiley Periodicals, Inc. Head Neck 38: E981-E986, 2016., (© 2015 Wiley Periodicals, Inc.)