Enhanced oxidative stress resistance in Ustilago maydis and its implications on the virulence.

The phytopathogenic fungus Ustilago maydis causes corn smut by suppressing host plant defenses, including the oxidative burst response. While many studies have investigated how U. maydis responds to oxidative stress during infection, the consequences of heightened resistance to oxidative stress on virulence remain understudied. This study aimed to identify the effects on virulence in U. maydis strains exhibiting enhanced resistance to hydrogen peroxide (H2O2).To achieve this, we exposed U. maydis SG200 to 20 escalating H2O2 shocks, resulting in an adapted strain resistant to concentrations as high as 60 mM of H2O2, a lethal dose for the initial strain. Genetic analysis of the adapted strain revealed five nucleotide substitutions, two minor copy number variants, and a large amplification event on chromosome nine (1-149 kb) encompassing the sole catalase gene. Overexpressing catalase increased resistance to H2O2; however, this resistance was lower than that observed in the adapted strain. Additionally, virulence was reduced in both strains with enhanced H2O2 resistance.In summary, enhanced H2O2 resistance, achieved through either continuous exposure to the oxidative agent or through catalase overexpression, decreased virulence. This suggests that the response to the oxidative stress burst in U. maydis is optimal and that increasing the resistance to H2O2 does not translate into increased virulence. These findings illuminate the intricate relationship between oxidative stress resistance and virulence in U. maydis, offering insights into its infection mechanisms.

Revealing the Role of Noncovalent Interactions on the Conformation of the Methyl Group in Tricyclic Orthoamide.

Tricyclic orthoamides are valuable molecules with wide-ranging applications, including organic synthesis and molecular recognition. Their structural properties make them intriguing, particularly the eclipsed all-trans conformer, which is typically less stable than the alternated conformation and is a rare phenomenon in organic chemistry. However, it gains stability in crystalline and hydrated settings, challenging the existing theoretical explanations. This study investigates which factors make eclipsed conformers more stable using experimentally reported anhydrous (ATO) and hydrated (HTO) crystal structures. Employing the quantum theory of atoms in molecules, noncovalent interaction index, and pairwise energy decomposition analysis, we delve into the noncovalent interaction environment surrounding the molecule of interest. In ATO, dispersive interactions dominate, whereas in HTO, both dispersive and electrostatic contributions are observed due to the presence of water molecules. Anchored to the lone pairs of the nitrogen atom in the orthoamide tricycle, water molecules prompt the methyl group's eclipsing through intermolecular and intramolecular interactions. This work resolves the long-standing conflict behind why tricyclic orthoamide has an eclipsed conformation by establishing the stabilization factors. These insights have implications for crystal engineering and design, enhancing our understanding of structural behavior in both crystalline and hydrated environments.

3D Tortuosity computation as a shape descriptor and its application to brain structure analysis.

In this study, we propose a novel method for quantifying tortuosity in 3D voxelized objects. As a shape characteristic, tortuosity has been widely recognized as a valuable feature in image analysis, particularly in the field of medical imaging. Our proposed method extends the two-dimensional approach of the Slope Chain Code (SCC) which creates a one-dimensional representation of curves. The utility of 3D tortuosity ( τ 3 D ) as a shape descriptor was investigated by characterizing brain structures. The results of the τ 3 D computation on the central sulcus and the main lobes revealed significant differences between Alzheimer's disease (AD) patients and control subjects, suggesting its potential as a biomarker for AD. We found a p < 0.05 for the left central sulcus and the four brain lobes.

Controlled Human Infection Models To Accelerate Vaccine Development.

The timelines for developing vaccines against infectious diseases are lengthy, and often vaccines that reach the stage of large phase 3 field trials fail to provide the desired level of protective efficacy. The application of controlled human challenge models of infection and disease at the appropriate stages of development could accelerate development of candidate vaccines and, in fact, has done so successfully in some limited cases. Human challenge models could potentially be used to gather critical information on pathogenesis, inform strain selection for vaccines, explore cross-protective immunity, identify immune correlates of protection and mechanisms of protection induced by infection or evoked by candidate vaccines, guide decisions on appropriate trial endpoints, and evaluate vaccine efficacy. We prepared this report to motivate fellow scientists to exploit the potential capacity of controlled human challenge experiments to advance vaccine development. In this review, we considered available challenge models for 17 infectious diseases in the context of the public health importance of each disease, the diversity and pathogenesis of the causative organisms, the vaccine candidates under development, and each model's capacity to evaluate them and identify correlates of protective immunity. Our broad assessment indicated that human challenge models have not yet reached their full potential to support the development of vaccines against infectious diseases. On the basis of our review, however, we believe that describing an ideal challenge model is possible, as is further developing existing and future challenge models.

Dating the evolution of the complex thalloid liverworts (Marchantiopsida): total-evidence dating analysis supports a Late Silurian-Early Devonian origin and post-Mesozoic morphological stasis.

Divergence times based on molecular clock analyses often differ from those derived from total-evidence dating (TED) approaches. For bryophytes, fossils have been excluded from previous assessments of divergence times, and thus, their utility in dating analyses remains unexplored. Here, we conduct the first TED analyses of the complex thalloid liverworts (Marchantiopsida) that include fossils and evaluate macroevolutionary trends in morphological 'diversity' (disparity) and rates. Phylogenetic analyses were performed on a combined dataset of 130 discrete characters and 11 molecular markers (sampled from nuclear, plastid and mitochondrial genomes). Taxon sampling spanned 56 extant species - representing all the orders within Marchantiophyta and extant genera within Marchantiales - and eight fossil taxa. Total-evidence dating analyses support the radiation of Marchantiopsida during Late Silurian-Early Devonian (or Middle Ordovician when the outgroup is excluded) and that of Ricciaceae in the Middle Jurassic. Morphological change rate was high early in the history of the group, but it barely increased after Late Cretaceous. Disparity-through-time analyses support a fast increase in diversity until the Middle Triassic (c. 250 Ma), after which phenotypic evolution slows down considerably. Incorporating fossils in analyses challenges previous assumptions on the affinities of extinct taxa and indicates that complex thalloid liverworts radiated c. 125 Ma earlier than previously inferred.

Wavefront reconstruction of discontinuous phase objects from optical deflectometry.

One of the challenges of phase measuring deflectometry is to retrieve the wavefront from objects that present discontinuities or non-differentiable gradient fields. Here, we propose the integration of such gradient fields based on an L p-norm minimization problem. The solution of this problem results in a nonlinear partial differential equation, which can be solved with a fast and well-known numerical method and does not depend on external parameters. Numerical reconstructions on both synthetic and experimental data are presented that demonstrate the capability of the proposed method.

Inter- and Intra-Operator Variability of Regularized Backscatter Quantitative Ultrasound for the Characterization of Breast Masses.

OBJECTIVES: Here we report on the intra- and inter-operator variability of the backscatter coefficient (BSC) estimated with a new low-variance quantitative ultrasound (QUS) approach applied to breast lesions in vivo. METHODS: Radiofrequency (RF) echo signals were acquired from 29 BIRADS 4 and 5 breast lesions in 2 sequential cohorts following 2 imaging protocols: cohort 1) radial and antiradial views, and cohort 2) short- and long-axis views. Protocol 2 was implemented after retraining and discussion on how to improve reproducibility. Each patient was scanned by at least 2 of 3 radiologists; each performed 3 acquisitions with transducer and patient repositioning in between acquisitions. BSC was estimated using a low-variance QUS approach based on regularization. Intra- and inter-operator variability of the intra-lesion median BSC was evaluated with a multifactorial ANOVA test (P-values) and the intraclass correlation coefficient (ICC). RESULTS: Inter-operator variability was only significant in the first protocol (P < .007); ICCinter = .77 (95% CI .71-.82), indicating good inter-operator agreement. In the second protocol, the inter-operator variability was not significant (P > .05) and agreement was excellent (ICCinter = .92 [.89-.94]). In both protocols, the intra-operator variability was not significant. CONCLUSIONS: Our findings demonstrate the need for standardizing image acquisition protocols for backscatter-based QUS to reduce inter-operator variability and ensure its successful translation to the characterization of suspicious breast masses.

The role of paleontological data in bryophyte systematics.

Systematics reconstructs tempo and mode in biological evolution by resolving the phylogenetic fabric of biodiversity. The staggering duration and complexity of evolution, coupled with loss of information (extinction), render exhaustive reconstruction of the evolutionary history of life unattainable. Instead, we sample its products-phenotypes and genotypes-to generate phylogenetic hypotheses, which we sequentially reassess and update against new data. Current consensus in evolutionary biology emphasizes fossil integration in total-evidence analyses, requiring in-depth understanding of fossils-age, phenotypes, and systematic affinities-and a detailed morphological framework uniting fossil and extant taxa. Bryophytes present a special case: deep evolutionary history but sparse fossil record and phenotypic diversity encompassing small dimensional scales. We review how these peculiarities shape fossil inclusion in bryophyte systematics. Paucity of the bryophyte fossil record, driven primarily by phenotypic (small plant size) and ecological constraints (patchy substrate-hugging populations), and incomplete exploration, results in many morphologically isolated, taxonomically ambiguous fossil taxa. Nevertheless, instances of exquisite preservation and pioneering studies demonstrate the feasibility of including bryophyte fossils in evolutionary inference. Further progress will arise from developing extensive morphological matrices for bryophytes, continued exploration of the fossil record, re-evaluation of previously described fossils, and training specialists in identification and characterization of bryophyte fossils, and in bryophyte morphology.

Liverwort oil bodies: diversity, biochemistry, and molecular cell biology of the earliest secretory structure of land plants.

Liverworts are known for their large chemical diversity. Much of this diversity is synthesized and enclosed within oil bodies (OBs), a synapomorphy of the lineage. OBs contain the enzymes to biosynthesize and store large quantities of sesquiterpenoids and other compounds while limiting their cytotoxicity. Recent important biochemical and molecular discoveries related to OB formation, diversity, and biochemistry allow comparison with other secretory structures of land plants from an evo-devo perspective. This review addresses and discusses the most recent advances in OB origin, development, and function towards understanding the importance of these organelles in liverwort physiology and adaptation to changing environments. Our mapping of OB types and chemical compounds to the current liverwort phylogeny suggests that OBs were present in the most recent common ancestor of liverworts, supporting that OBs evolved as the first secretory structures in land plants. Yet, we require better sampling to define the macroevolutionary pattern governing the ancestral type of OB. We conclude that current efforts to find molecular mechanisms responsible for the morphological and chemical diversity of secretory structures will help understand the evolution of each major group of land plants, and open new avenues in biochemical research on bioactive compounds in bryophytes and vascular plants.

Leucism: the prevalent congenital malformation in the olive ridley sea turtle of northwestern Mexico.

Despite being the most abundant sea turtle in the world, the olive ridley turtle Lepidochelys olivacea is classified as Vulnerable by the IUCN. There is evidence of congenital malformations in hatchlings, and the associated causes are multifactorial, with both genetic and environmental sources. Santuario Playa Ceuta (SPC) is a sanctuary for the olive ridley, located at the northernmost region of its nesting range in the Mexican Pacific. The objective of this study was to identify and quantify the prevalence and severity of congenital malformations in olive ridley embryos/hatchlings in SPC during the 2017 nesting season. We collected 62907 eggs from 643 relocated nests that were moved to a hatchery, of which 4242 eggs with obvious development did not hatch and were analyzed for this study. Hatching success was 53.9%, with 22.5% of nests (n = 145) and 0.54% of eggs (n = 344) showing embryos or hatchlings with malformations. The nest severity index was 2.4 (range: 1-10) malformed embryos or hatchlings per nest, and the organism severity index was 1.4 (range: 1-7) malformations per malformed embryo or hatchling. Leucism was the most prevalent malformation (34.4%; 170/494 total observed), with the craniofacial region showing the greatest diversity of malformations (17/35 types). Given the geographical position of SPC, extreme environmental conditions (e.g. cold, heat, and dryness) could be one of the main causes of teratogenesis in this species. However, more studies are needed regarding the presence of contaminants, genetic factors, health assessments of nesting females, and malformation rates of nests that remain in situ versus those that are relocated.

Smart Multi-Sensor System for Remote Air Quality Monitoring Using Unmanned Aerial Vehicle and LoRaWAN.

Deaths caused by respiratory and cardiovascular diseases have increased by 10%. Every year, exposure to high levels of air pollution is the cause of 7 million premature deaths and the loss of healthy years of life. Air pollution is generally caused by the presence of CO, NO2, NH3, SO2, particulate matter PM10 and PM2.5, mainly emitted by economic activities in large metropolitan areas. The problem increases considerably in the absence of national regulations and the design, installation, and maintenance of an expensive air quality monitoring network. A smart multi-sensor system to monitor air quality is proposed in this work. The system uses an unmanned aerial vehicle and LoRa communication as an alternative for remote and in-situ atmospheric measurements. The instrumentation was integrated modularly as a node sensor to measure the concentration of carbon monoxide (CO), nitrogen dioxide (NO2), ammonia (NH3), sulfur dioxide (SO2), and suspended particulate mass PM10 and PM2.5. The optimal design of the multi-sensor system has been developed under the following constraints: A low weight, compact design, and low power consumption. The integration of the multi-sensor device, UAV, and LoRa communications as a single system adds aeeded flexibility to currently fixed monitoring stations.

Defying death: incorporating fossils into the phylogeny of the complex thalloid liverworts (Marchantiidae, Marchantiophyta) confirms high order clades but reveals discrepancies in family-level relationships.

In recent years, the use of extensive molecular and morphological datasets has clarified the phylogenetic relationships among the orders of complex thalloid liverworts (Marchantiidae). However, previous studies excluded extinct taxa; thereby, undersampling the actual taxonomic diversity of the group. Here, we conducted a total-evidence analysis of Marchantiidae incorporating fossils. The combined dataset consisted of 11 genes-sampled from the nuclear, mitochondrial and plastid genomes-and 128 morphological characters. Sixty-two species, representing all classes and orders within Marchantiophyta and genera within Marchantiidae were included in the analyses. Six fossils were scored from literature: two assigned to the outgroup (Metzgeriothallus sharonae and Pallaviciniites sandaolingensis) and four to the ingroup (Marchantites cyathodoides, M. huolinhensis, Ricciopsis ferganica and R. sandaolingensis). Tree searches were conducted using parsimony as the optimality criterion. Clade sensitivity was assessed across a wide range of weighting regimes. Also, we evaluated the influence of fossils on the inferred topologies and branch support. Our results were congruent with previously inferred clades above the order level: Neohodgsoniales was sister to a clade formed by Sphaerocarpales and Marchantiales. However, relationships among families within Marchantiales contradicted recent studies. For instance, a clade consisting of Monosoleniaceae, Wiesnerellaceae and Targioniaceae was sister to the morphologically simple taxa instead of being nested within them as in previous studies. Novel synapomorphies were found for several clades within Marchantiales. Outgroup fossils were more influential than Marchantiidae fossils on overall topologies and branch support values. Except for a single weighting scheme, sampling continuous characters and down-weighting characters improved fossil stability. Ultimately, our results challenge the widespread notion that bryophyte fossils are problematic for phylogenetic inference.

Cortical Thickness Estimation: A Comparison of FreeSurfer and Three Voxel-Based Methods in a Test-Retest Analysis and a Clinical Application.

The cortical thickness has been used as a biomarker to assess different cerebral conditions and to detect alterations in the cortical mantle. In this work, we compare methods from the FreeSurfer software, the Computational Anatomy Toolbox (CAT12), a Laplacian approach and a new method here proposed, based on the Euclidean Distance Transform (EDT), and its corresponding computational phantom designed to validate the calculation algorithm. At region of interest (ROI) level, within- and inter-method comparisons were carried out with a test-retest analysis, in a subset comprising 21 healthy subjects taken from the Multi-Modal MRI Reproducibility Resource (MMRR) dataset. From the Minimal Interval Resonance Imaging in Alzheimer's Disease (MIRIAD) data, classification methods were compared in their performance to detect cortical thickness differences between 23 healthy controls (HC) and 45 subjects with Alzheimer's disease (AD). The validation of the proposed EDT-based method showed a more accurate and precise distance measurement as voxel resolution increased. For the within-method comparisons, mean test-retest measures (percentages differences/intraclass correlation/Pearson correlation) were similar for FreeSurfer (1.80%/0.90/0.95), CAT12 (1.91%/0.83/0.91), Laplacian (1.27%/0.89/0.95) and EDT (2.20%/0.88/0.94). Inter-method correlations showed moderate to strong values (R > 0.77) and, in the AD comparison study, all methods were able to detect cortical alterations between groups. Surface- and voxel-based methods have advantages and drawbacks regarding computational demands and measurement precision, while thickness definition was mainly associated to the cortical thickness absolute differences among methods. However, for each method, measurements were reliable, followed similar trends along the cortex and allowed detection of cortical atrophies between HC and patients with AD.

North American Society for Pediatric Gastroenterology, Hepatology and Nutrition and the Society for Pediatric Radiology Joint Position Paper on Noninvasive Imaging of Pediatric Pancreatitis: Literature Summary and Recommendations.

ABSTRACT: The reported incidence of pediatric pancreatitis is increasing. Noninvasive imaging, including ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI), play important roles in the diagnosis, staging, follow-up, and management of pancreatitis in children. In this position paper, generated by members of the Pancreas Committee of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) and the Abdominal Imaging Committee of The Society for Pediatric Radiology (SPR), we review the roles of noninvasive imaging in pediatric acute, acute recurrent, and chronic pancreatitis. We discuss available evidence related to noninvasive imaging, highlighting evidence specific to pediatric populations, and we make joint recommendations for use of noninvasive imaging. Further, we highlight the need for research to define the performance and role of noninvasive imaging in pediatric pancreatitis.

Least-squares gamma estimation in fringe projection profilometry.

This paper introduces a novel, to the best of our knowledge, method to estimate and compensate the nonlinear gamma factor introduced by the optical system in fringe projection profilometry. We propose to determine this factor indirectly by adjusting the least-squares plane to the estimated phase coming from the reference plane. We only require a minimal set of three fringe sinusoidal images to estimate the gamma factor. This value can be used to rectify computational legacy data and also to generate and project the new set of fringe patterns for which we perform the inverse gamma compensation. Experimental results demonstrate the feasibility of the proposed method to estimate and correct the gamma distortion.

Timber and non-timber forest products in the northernmost Neotropical rainforest: Ecological factors unravel their landscape distribution.

The benefits provided by tropical rainforests are unevenly distributed throughout the landscape and are shaped by abiotic and biotic components that influence the spatial distribution and functional traits of the species involved. We tested whether environmental stratification of the rainforest in biophysical Landscape Units (LU), defined by topography and soil, is related to the spatial distribution of diversity, abundance and productivity (standing biomass) of tree assemblages that provide potential forest products (PFP). Considering that different PFP are associated with specific plant traits, we also tested whether a phylogenetic signal exists among the species that comprise specific use categories. Non-metric multidimensional scaling ordinations and permutational analysis of variance were based on the frequency, abundance and productivity of 129 species, the PFP of which were classified as fodder, food, fuelwood, medicinal, melliferous, ornamental, plywood and timber in 15 plots of 0.5 ha each. We constructed a phylogenetic tree of the studied species and analyzed the phylogenetic signal strength (D-statistic) among them. The spatial distribution of diversity and abundance of useful species changes among the LU. Specific PFP can be provided in contrasting habitat conditions, but generally not by the same species. The PFP categories that presented a phylogenetic signal were associated with wood characteristics (fuelwood and plywood) and the palatability of the leaves and reproductive structures (fodder). The Moraceae family was significantly related to fodder and plywood, whereas Meliaceae, Myrtaceae and Sapotaceae were mostly used for fuelwood. The medicinal species presented convergent traits distributed throughout the phylogeny. However, since our study included a broad variety of plant structures, it is possible that phylogenetic dispersion can change if we consider the specific uses within each category. Our findings show that the assemblages of PFP suppliers can be clustered through biophysical units based on soil and topography, and specific categories of PFP are often supplied by phylogenetically related species. This knowledge is fundamental in order to incorporate the high diversity of tree species and their potential uses into productive reforestation and agroforestry programs.

A novel voxel-based method to estimate cortical sulci width and its application to compare patients with Alzheimer's disease to controls.

A voxel-based method for measuring sulcal width was developed, validated and applied to a database. This method (EDT-based LM) employs the 3D Euclidean Distance Transform (EDT) of the pial surface and a Local Maxima labeling algorithm. A computational phantom was designed to test method performance; results revealed the method's inaccuracy δ, to range between 0.1 and 0.5 voxels, for a width that varied between 1 and 7 voxels. Two morphological descriptors were computed to characterize each defined sulcus: mean sulcal width (MSW) and mean absolute deviation (MAD). The former is the average width for all available width measurements within the sulcus, and the latter is the deviation of these measurements. The EDT-based LM method was applied to the Minimal Interval Resonance Imaging in the Alzheimer's Disease (MIRIAD) database, for a set of high-resolution Magnetic Resonance (MR) images of 66 subjects: 43 patients with Alzheimer Disease (AD) and 23 control subjects. AD causes significant gray matter loss; hence, some sulci were expected to broaden. Methodological results concurred with this hypothesis. After a Wilcoxon test, MSW was grater in the case of all sulci pertaining to AD patients, (p < 0.05, FDR corrected), whereas MAD showed significant differences in 8 sulci (p < 0.05, FDR corrected). This work presents a novel voxel-based method for measuring sulcal width and extracting descriptors to characterize and compare the sulci within and across subjects.

Reassessing the role of morphology in bryophyte phylogenetics: Combined data improves phylogenetic inference despite character conflict.

Morphological data has gained renewed attention and has been shown to be crucial in clarifying the phylogenetic relationship in a wide range of taxa. In the last decades, phylogenetic analyses of sequence-level data have radically modified the systematic schemes within bryophytes (early non-vascular land plants) and have revealed a widespread pattern of conflict with morphology-based classifications. Yet, a comprehensive evaluation of character conflict has not yet been performed in the context of combined matrices. In this study, we evaluate the impact of morphology on bryophyte phylogeny following a total-evidence approach across 10 published matrices. The analysed matrices span a wide range of bryophytes, taxonomic levels, gene sampling and number of morphological characters and taxa. Data conflict was addressed by measuring: (i) the topological congruence between individual partitions, (ii) changes in support values of the combined data relative to the molecular partition and (iii) clade stability. The association between these measures and the number of morphological characters per taxon (Nc/T ratio) and the proportion of non-fixed characters (i.e., inapplicable, polymorphic and missing data) was explored. In the individual partition analyses, the Nc/T ratio correlated positively with the topological congruence in six to seven datasets depending on the weighting scheme. The proportion of non-fixed cells had a minor influence on congruence between data partitions. The number of characters and proportion of non-fixed data varied significantly between morphological datasets that improved congruence between data types. This variation suggests that morphological datasets affect the results of combined analyses in different ways, depending on the taxa studied. Combined analyses revealed that, despite the low congruence values between partitions, integrating data types improves support values and stability. However, while non-fixed data had no negative effect on support values, stability was reduced as the proportion of non-fixed cells increased. Nc/T ratio was negatively associated with support values and it showed ambiguous responses in stability evaluations. Overall, the results indicate that adding morphology may contribute to the inference of phylogenetic relationships of bryophytes despite character conflict. Our findings suggest that merely comparing (a) morphology-based classifications with molecular phylogenies or (b) the outcome from individual data partitions can misestimate data conflict. These findings imply that analyses of combined data may provide conservative assessments of data conflict and, eventually, lead to an improved sampling of morphological characters in large-scale analyses of bryophytes.

Exploring the phylogeny of the marattialean ferns.

The eusporangiate marattialean ferns represent an ancient radiation with a rich fossil record but limited modern diversity in the tropics. The long evolutionary history without close extant relatives has confounded studies of the phylogenetic origin, rooting and timing of marattialean ferns. Here we present new complete plastid genomes of six marattialean species and compiled a plastid genome dataset representing all of the currently accepted marattialean genera. We further supplemented this dataset by compiling a large dataset of mitochondrial genes and a phenotypic data matrix covering both extant and extinct representatives of the lineage. Our phylogenomic and total-evidence analyses corroborated the postulated position of marattialean ferns as the sister to leptosporangiate ferns, and the position of Danaea as the sister to the remaining extant marattialean genera. However, our results provide new evidence that Christensenia is sister to Marattia and that M. cicutifolia actually belongs to Eupodium. The apparently highly reduced rate of molecular evolution in marattialean ferns provides a challenge for dating the key phylogenetic events with molecular clock approaches. We instead applied a parsimony-based total-evidence dating approach, which suggested a Triassic age for the extant crown group. The modern distribution can best be explained as mainly resulting from vicariance following the breakup of Pangaea and Gondwana. We resolved the fossil genera Marattiopsis, Danaeopsis and Qasimia as members of the monophyletic family Marattiaceae, and the Carboniferous genera Sydneia and Radstockia as the monophyletic sister of all other marattialean ferns.

Taxon incompleteness and discrete time bins affect character change rates in simulated data.

Estimating how fast or slow morphology evolves through time (phenotypic change rate, PR) has become common in macroevolutionary studies and has been important for clarifying key evolutionary events. However, the inclusion of incompletely scored taxa (e.g. fossils) and variable lengths of discrete arbitrary time bins could affect PR estimates and potentially mask real PR patterns. Here, the impact of taxon incompleteness (unscored data) on PR estimates is assessed in simulated data. Three different time bin series were likewise evaluated: bins evenly spanning the tree length (i), a shorter middle bin and longer first and third bins (ii), and a longer middle bin and shorter first and third bins (iii). The results indicate that PR values decrease as taxon incompleteness increases. Statistically significant PR values, and the dispersion among PR values, depended on the time bins. These outcomes imply that taxon incompleteness can undermine our capacity to infer morphology evolutionary dynamics and that these estimates are also influenced by our choice of discrete time bins. More importantly, the present results stress the need for a better approach to deal with taxon incompleteness and arbitrary discrete time bins.