Southern Latitudes Research Articles

Maximum entropy modelling to identify optimal locations for an IMTA system comprising Sparus aurata, Mytilus galloprovincialis and Ulva rigida on Europe’s Atlantic coastline

Meeting the resource demand for an increasing human population has led to the emergence of the aquaculture industry as the fastest growing sector for food production worldwide. Modern finfish aquaculture has raised environmental concerns and, to address this, Integrated Multi-Trophic Aquaculture (IMTA) has gained popularity as a means to minimise environmental impacts. This is done by culturing extractive species alongside fed species to utilise excess nutrients and enhance their own growth. The current study, based within the Atlantic Area of Europe, identified suitable habitats for the three species Sparus aurata, Mytilus galloprovincialis and Ulva rigida, for use in a new IMTA system. Models were created using MaxEnt software and input into GIS software (ArcMap 10.8.1) for analysis. For all species, the AUC results in the model were >0.9, with values of 0.931 (S. aurata), 0.928 (M. galloprovincialis) and 0.939 (U. rigida), demonstrating significant predictive power. Jackknife testing of the model for each species identified the mean sea surface temperature (°C) and Chlorophyll A (mg m–3) concentration as the two most important variables. The model showed that areas of >50% suitability could be found throughout the study area, although the most suitable sites were in coastal areas in more southern latitudes. To identify the feasibility of establishing an IMTA system in different areas, the shipping density, MPA status and the locations of harbours were added to the maps for further consideration. Using this study, and the species-specific information identified by the model, the aquaculture industry will be better equipped to identify potential IMTA sites and integrate these systems into the EU market for sustainable production.

Genome-wide association study reveals 18 QTL for major agronomic traits in a Nordic-Baltic spring wheat germplasm.

Spring wheat (Triticum aestivum L.) remains an important alternative to winter wheat cultivation at Northern latitudes due to high risk of overwintering or delayed sowing of winter wheat. We studied nine major agronomic traits in a set of 299 spring wheat genotypes in trials across 12-year-site combinations in Lithuania, Latvia, Estonia, and Norway for three consecutive years. The dataset analyzed here consisted of previously published phenotypic data collected in 2021 and 2022, supplemented with additional phenotypic data from the 2023 field season collected in this study. We combined these phenotypic datasets with previously published genotypic data generated using a 25K single nucleotide polymorphism (SNP) array that yielded 18,467 markers with a minor allele frequency above 0.05. Analysis of these datasets via genome-wide association study revealed 18 consistent quantitative trait loci (QTL) replicated in two or more trials that explained more than 5% of phenotypic variance for plant height, grain protein content, thousand kernel weight, or heading date. The most consistent markers across the tested environments were detected for plant height, thousand kernel weight, and days to heading in eight, five, and six trials, respectively. No beneficial effect of the semi-dwarfing alleles Rht-B1b and Rht-D1b on grain yield performance was observed across the 12 tested trials. Moreover, the cultivars carrying these alleles were low yielding in general. Based on principal component analysis, wheat genotypes developed in the Northern European region clustered separately from those developed at the southern latitudes, and markers associated with the clustering were identified. Important phenotypic traits, such as grain yield, days to heading, grain protein content, and thousand kernel weight were associated with this clustering of the genotype sets. Interestingly, despite being adapted to the Nordic environment, genotypes in the Northern set demonstrated lower grain yield performance across all tested environments. The results indicate that spring wheat germplasm harbors valuable QTL/alleles, and the identified trait-marker associations might be useful in improving Nordic-Baltic spring wheat germplasm under global warming conditions.

Alergiczne zapalenie spojówek

Allergic conjunctivitis is the most common manifestation of conjunctivitis, affecting up to 40% of the population, mostly children and young adults. Among the risk factors there are air pollution, southern latitude and coexisting allergy. The disease develops when IgE-class antibodies are activated by an allergen and later Th2-dependent humoral response is activated. In seasonal and perennial allergic conjunctivitis the symptoms are limited to conjunctiva, however in vernal keratoconjunctivitis and atopic keratoconjunctivitis also the cornea can be affected. Giant papillary conjunctivitis is not an allergy but a response to irritating surface agents, most frequently a contact lens. In treatment there are three groups of medications used: antihistaminic, non-steroid anti inflammatory and steroids. Due to rise of allergic conjunctivitis, it is crucial to accurately diagnose and treat those conditions.

Surface Ocean Cooling in the Eocene North Atlantic Coincides With Declining Atmospheric CO2

AbstractThe Eocene (56–34 million years ago) is characterized by declining sea surface temperatures (SSTs) in the low latitudes (∼4°C) and high southern latitudes (∼8–11°C), in accord with decreasing CO2 estimates. However, in the mid‐to‐high northern latitudes there is no evidence for surface water cooling, suggesting thermal decoupling between northern and southern hemispheres and additional non‐CO2 controls. To explore this further, we present a multi‐proxy (Mg/Ca, δ18O, TEX86) SST record from Bass River in the western North Atlantic. Our compiled multi‐proxy SST record confirms a net decline in SSTs (∼4°C) between the early Eocene Climatic Optimum (53.3–49.1 Ma) and mid‐Eocene (∼44–41 Ma), supporting declining atmospheric CO2 as the primary mechanism of Eocene cooling. However, from the mid‐Eocene onwards, east‐west North Atlantic temperature gradients exhibit different trends, which we attribute to incursion of warmer waters into the eastern North Atlantic and inception of Northern Component Water across the early‐middle Eocene transition.

Morphological analysis of polar landing regions for a solar powered ice drilling mission

Planning of mission toward the lunar polar region is supported here by the analysis and better understanding of the most frequent landforms: craters on the Moon in the polar region between 79.30 and 84.35 southern latitude. This work surveys impact crater morphologies and spatial density based age estimation and slopes for eight earlier selected, large candidate landing regions of the Luna-27 solar powered ice drilling mission at the southern lunar polar region. The morphological, morphometrical, slope and dating analysis provided the following results: The d/D values of craters follow the earlier found d/D trend for larger craters, but there is a scatter in depth values related to the ageing of craters. The occurrence of shallow craters looks to be somewhat more abundant here than at lower lunar latitudes, in agreement with Mahanti et al. (2015). Beside fresh craters, rock boulders also occur at some km sized local topographic elevations, indicating erosion of ∼1 m thick regolith layer by micro-scale impacts roughly on the scale of 100 Ma.Characteristic temporal sequence of change in the morphology of about 100 m-sized craters confirmed earlier results. The sequence starts from the freshest craters, with mass wasting produced stripes in the interior slope, later diminish of high-reflectance proximal ejecta happens, then boulders, and even later elevated rims diminish. The surveyed large terrains showed crater statistics-derived model ages ranged between 3.9 and 4.2 Ga, indicating below a thin pulverised surface regolith layer, the topography of the poorly fragmented bedrock below it still holds the Late Heavy Bombardment aged basement. The equilibrium crater population was possibly identified below the 100–200 m diameter range. Surveying crater retention at >30° slopes indicates exposure of 78–140 Ma for steep terrains, and 330–150 Ma for flat <5° slope surfaces considering the size domain below 100 m diameter. This observation indicates rejuvenation of the top few m thin layer of slopes produces faster mixing than on plains.The surveyed kilometre sized craters formed about 1–2 Ga ago, and show correlation between formation age and depth, indicating an infilling rate around 100 m thickness in 1 Ga duration. This is 2 orders of magnitude larger than the 1–2 m impact driven regolith mixing depth during the same period. Thus, while impact mixing desiccates the shallow top regolith layer, inside km scale craters earlier accumulated ice might still be there shielded by faster rock debris accumulation.The surveyed candidate landing regions were evaluated according to general landing safety, lower temperature (to support ice preservation), and solar illumination (for energy supply). Comparing the eight regions, altogether 5.1% of their total area was found to meet with the threshold values of slope angle below 8°, modelled 1 m deep subsurface temperature below 125 K and at least 20% of time available solar illumination and Earth visibility. The largest continuous area that fulfil the used constraints are present in the candidate LS8 area at −82.70°, −82.72°.

Reanalysis of a dataset refutes claims of anagenesis within Tyrannosaurus-line tyrannosaurines (Theropoda, Tyrannosauridae)

The recently described tyrannosaurine (Theropoda, Tyrannosauridae) species Daspletosaurus wilsoni was suggested to show evidence for anagenesis within the genus Daspletosaurus and derived Tyrannosaurinae. Here, we evaluate the methodology and conclusions made by the authors. Reanalysis of their dataset with additions and consistently applied methodologies, shows that there is no strong evidence for a single anagenetic lineage within ‘Tyrannosaurus-line’ tyrannosaurines throughout the latest Cretaceous. Our study demonstrates a cladogenetic Tyrannosaurinae composed of four morphologically and biogeographically distinct clades. Two of these clades are formally defined and diagnosed herein (Teratophoneini clade nov. and Tyrannosaurini). Teratophoneini is currently restricted to the southern latitudes of Campanian Laramidia, while Tyrannosaurini is present in both Campanian and Maastrichtian strata in Asia and Laramidia. Inclusion of a currently unnamed species of Daspletosaurus from the Dinosaur Park and Oldman formations to the dataset reveals that anagenesis is not found to be a driver of speciation within Daspletosaurus. We also demonstrate that all known species of Daspletosaurus do not meet previously established prerequisites for anagenesis and advise against prematurity when making conclusions concerning significant processes surrounding the mode of evolution of extinct genera with sparse and often incomplete fossil records. Future detailed anatomical description of specimens representing the proposed fourth species of Daspletosaurus will further aid in elucidating the evolution of this genus and tyrannosaurines more generally.

Global analysis of Poales diversification - parallel evolution in space and time into open and closed habitats.

Poales are one of the most species-rich, ecologically and economically important orders of plants and often characterise open habitats, enabled by unique suites of traits. We test six hypotheses regarding the evolution and assembly of Poales in open and closed habitats throughout the world, and examine whether diversification patterns demonstrate parallel evolution. We sampled 42% of Poales species and obtained taxonomic and biogeographic data from the World Checklist of Vascular Plants database, which was combined with open/closed habitat data scored by taxonomic experts. A dated supertree of Poales was constructed. We integrated spatial phylogenetics with regionalisation analyses, historical biogeography and ancestral state estimations. Diversification in Poales and assembly of open and closed habitats result from dynamic evolutionary processes that vary across lineages, time and space, most prominently in tropical and southern latitudes. Our results reveal parallel and recurrent patterns of habitat and trait transitions in the species-rich families Poaceae and Cyperaceae. Smaller families display unique and often divergent evolutionary trajectories. The Poales have achieved global dominance via parallel evolution in open habitats, with notable, spatially and phylogenetically restricted divergences into strictly closed habitats.

A unique Late Cretaceous fossil wood assemblage from Chilean Patagonia provides clues to a high‐latitude continental environment

AbstractFossil plants, including large trunks, stems, some branches, and twigs, were collected from the Maastrichtian (68.9 Ma), upper Dorotea Formation in the Magallanes–Austral Basin, 16 km north of the Cerro Guido–Las Chinas complex in the southern Chilean Magallanes region. These fossil trunks range from 0.2 to 2.2 m in length. Petrographic slides were made in three sections (transverse, radial and tangential) and analysed under a light microscope to study the permineralized fossils. The woods and stems belong to Austroginkgoxylon gen. et sp. nov., Agathoxylon antarcticum, Podocarpoxylon paradoxi sp. nov., Podocarpoxylon mazzonii, Palmoxylon subantarcticae and Notomalvaceoxylon magallanense gen. et sp. nov. The growth rings of gymnosperms and anatomical characters of angiosperms were analysed to obtain palaeoecological data. Interactions between gymnosperm roots growing into the secondary xylem of an angiosperm (nurse logs) are recorded. The data obtained from the fossil woods suggest warm and humid conditions in this southern South American locality during the Late Cretaceous, providing a unique opportunity to study continental environments at high southern latitudes, which are poorly represented on a global scale.

Water temperature and season length interact to explain a rare non‐linear ecogeographic cline in body size

AbstractAimAdult body size often exhibits patterns across large‐scale environmental gradients, creating ecogeographic clines. However, the form of body size clines varies across taxonomic groups, with linear and non‐linear patterns in body size observed in nature. Non‐linear body size clines have received less study, and questions remain about how environmental gradients interact to produce non‐linear clines. We examined the body size of the American horseshoe crab (Limulus polyphemus), a widely distributed marine arthropod, and evaluated the hypothesis that temperature and active season length can interact multiplicatively to result in a dome‐shaped distribution.LocationFourteen states in the United States of America and three Mexican states, representing the entire geographic range of the species.MethodsWe compiled environmental data and body size measurements from more than 49,000 individual horseshoe crabs. For each location, we extracted from the literature or calculated from raw data the mean male prosoma width and the mean female prosoma width. We applied a general additive modelling (GAM) approach to characterize the body size cline, test a hypothesis regarding temperature and season length, and explore evidence for the influence of additional environmental factors.ResultsModel results indicate temperature and season length could act multiplicatively to produce dome‐shaped clines, and these findings align with and quantify previous anecdotal reports of a strong dome‐shaped body size cline across latitude for horseshoe crabs.Main ConclusionsActive season length appears to become relatively more influential on horseshoe crab body size in the northern part of their range, while temperature effects per se appear to dominate in southern latitudes. For horseshoe crabs, the pattern of size variation is consistent with the predictions of Optimal Resource Allocation models, but more study is needed to elucidate mechanistic underpinnings. Considering climate change projections, results from our study suggest future shifts in horseshoe crab body sizes.

Oral Contraceptive Pills Increase Circulating 25-Hydroxy-Vitamin D Concentrations in Women Who Are Lactating.

This article aims to determine the association between maternal 25-hydroxy-vitamin D [25(OH)D] status and intake of hormonal oral contraceptive pills (OCPs) in women who are lactating. Women who were exclusively breastfeeding participated in a randomized controlled trial assessing vitamin D supplementation at 400, 2,400, or 6,400 international unit (IU)/d from 1 month through 7 months postpartum. This observational, secondary analysis assessed whether OCPs were associated with maternal 25(OH)D concentrations in women who are lactating. Multivariate regression models were used to predict 25(OH)D concentrations and create parameter estimates for each variable. In a bivariate analysis, the use of OCPs at 4 months was associated with increased serum 25(OH)D (p = 0.02). OCPs' use at 7 months was associated with a higher trend in 25(OH)D, but this finding was not statistically significant (p = 0.1). In a multivariate regression model at 4 months, independent positive predictors of 25(OH)D concentrations were the use of OCPs (p = 0.03) and treatment with vitamin D at 6,400 IU/d (p ≤ 0.0001). Negative predictors were Black (p = 0.001) and Hispanic (p = 0.0001) race and ethnicity, and body mass index (BMI) greater than 30 (p = 0.0002). The same pattern occurred at 7 months, with more southern latitude as a positive independent predictor (p = 0.04) of 25(OH)D concentration. The use of OCPs was associated with greater 25(OH)D in women who are lactating. Additionally, treatment with vitamin D at 6,400 IU/d and southern latitude was associated with greater 25(OH)D in women who are lactating. Black and Hispanic race and ethnicity, and BMI greater than 30, were independently associated with lower 25(OH)D in women who are lactating. · The association of OCP with serum 25(OH)D concentrations during postpartum lactation is unknown.. · OCPs' use was associated with higher 25(OH)D concentrations in postpartum women who are lactating.. · Treatment with vitamin D and southern latitude was associated with greater 25(OH)D in women who are lactating.. · Black and Hispanic, and BMI > 30 were associated with lower 25(OH)D in women who are lactating.. · Practitioners can counsel women who are lactating on OCPs' use and the positive effects on their 25(OH)D status..

Size of emerald ash borer in North Carolina,USA: Preliminary evidence for a sawtooth cline?

AbstractWe test the hypothesis of Marshall et al. (2013) that in the United States there is a converse Bergmann's cline in body size ofAgrilus planipennis(emerald ash borer, EAB), with the largest females ( = 12.6 mm length) collected at the most southern latitudes tested (37° N).In 2020, we employed three techniques to collect EAB at a North Carolina (NC) site located at 35.64° N (purple prism traps [PPTs], log emergence,Cerceris fumipennisbiosurveillance). The study was repeated in 2021, but with green funnel traps replacing log emergence. EAB collected byC. fumipennisin three altitudinally disparate regions of NC were also measured.Overall, EAB collected in 2020 averaged 12.02 mm, with those emerged from logs significantly smaller than those from PPTs. Length of females collected fromC. fumipennisat three elevations was not significantly different and averaged 12.01 mm. In 2021, females collected from funnel traps, PPTs andC. fumipenniswere not significantly different and larger ( = 12.41 mm) than in 2020; eliminating the smaller log‐emerged EAB from the 2020 data set did not change the outcome.Mean EAB size in NC never reached the reported 12.6 mm at 37° N, regardless of the technique or altitude tested. Our expansion of the latitudinal range in which EAB body size has been studied may shift the proposed converse Bergmann's cline to that of a sawtooth or other non‐linear model, likely associated with a transition in EAB voltinism at or near NC latitudes.

Comparison of metabolic rate between two genetically distinct populations of lake sturgeon.

Environmental temperatures differ across latitudes in the temperate zone, with relatively lower summer and fall temperatures in the north leading to a shorter growing season prior to winter. As an adaptive response, during early life stages, fish in northern latitudes may grow faster than their conspecifics in southern latitudes, which potentially manifests as different allometric relationships between body mass and metabolic rate. In the present study, we examined if population or year class had an effect on the variation of metabolic rate and metabolic scaling of age-0 lake sturgeon (Acipenser fulvescens) by examining these traits in both a northern (Nelson River) and a southern (Winnipeg River) population. We compiled 6 years of data that used intermittent flow respirometry to measure metabolic rate within the first year of life for developing sturgeon that were raised in the same environment at 16°C. We then used a Bayesian modeling approach to examine the impacts of population and year class on metabolic rate and mass-scaling of metabolic rate. Despite previous reports of genetic differences between populations, our results showed that there were no significant differences in standard metabolic rate, routine metabolic rate, maximum metabolic rate, and metabolic scaling between the two geographically separated populations at a temperature of 16°C. Our analysis implied that the lack of metabolic differences between populations could be due to family effects/parental contribution, or the rearing temperature used in the study. The present research provided insights for conservation and reintroduction strategies for these populations of lake sturgeon, which are endangered or threatened across most of their natural range.

Wave perturbations in Earth’s thermosphere in conjunction with X1.7 solar flare: Observational perspective

Based on satellite observations, the study examines the effect of an X1.7 flare (which occurred on January 27, 2012) on neutral winds and the formation of wave perturbations in Earth’s thermosphere. The Gravity field and steady state Ocean Circulation Explorer (GOCE) observations of the thermospheric zonal wind speed show an increase of 100 m/s in the north polar and 400S to south polar regions on the day side associated with the X1.7 solar flare. This feature is absent for the geomagnetically quiet days in January 2012, when there are no X-class flares. The wave perturbations in thermosphere, derived from the zonal winds are observed to be strongest in the flare day, than in non-flare days, with power index 40. During the flare day, wave perturbation with a wavelength of about 1110 km is dominant and is found preferentially in southern latitudes (above 400S) on the day side. When compared to non-flare days, the TIMED-derived neutral temperature increases by 45 K around the equatorial zone. The measurements also show the substantial temperature gradients over latitude and longitude in the flare situation. This demonstrates the presence of high thermal gradients in the thermosphere caused by the X1.7 solar flare, which causes zonal wind amplification and the launching of strong waves in the thermosphere.

Parallel evolution in Crassostrea oysters along the latitudinal gradient is associated with variation in multiple genes involved in adipogenesis.

Parallel diversification provides a proper framework for studying the role of natural selection in evolution. Yet, empirical studies from ecological 'non-model' species of invertebrates are limited at the whole genome level. Here, we presented a chromosome-scale genome assembly for Crassostrea angulata and investigated the parallel genomic evolution in oysters. Specifically, we used population genomics approaches to compare two southern-northern oyster species pairs (C. angulata-C. gigas and southern-northern C. ariakensis) along the coast of China. The estimated divergence time of C. angulata and C. gigas is earlier than that of southern and northern C. ariakensis, which aligns with the overall elevated genome-wide divergence. However, the southern-northern C. ariakensis FST profile represented more extremely divergent "islands". Combined with recent reciprocal hybridization studies, we proposed that they are currently at an early stage of speciation. These two southern-northern oyster species pairs exhibited significant repeatability in patterns of genome-wide differentiation, especially in genomic regions with extremely high and low divergence. This suggested that divergent and purifying selection has contributed to the genomic parallelism between southern and northern latitudes. Top differentiated genomic regions shared in these two oyster species pairs contained candidate genes enriched for functions in energy metabolism, especially adipogenesis, which are closely related to reproductive behaviours. These genes might be good candidates for further investigation in vivo. In conclusion, our results suggest that similar divergent selection and shared genomic features could predictably transform standing genetic variation within one species pair into differences in another.

Home ranges and movement patterns of wild boars (Sus scrofa) at the northern edge of the species’ distribution range

In Finland, the wild boar (Sus scrofa L.) lives on the northernmost edge of the species’ distribution range, and the population mainly originates from individuals immigrating from Russia. Most of the current population lives in the southeastern part of the country, and the wild boar is steadily expanding further. To develop effective risk and population management in novel northern wild boar regions, detailed information about the species’ local ecology is required. To estimate wild boar movement patterns, 17 adult wild boars were monitored using GPS collars from May 2020 to September 2022 in the core region of the current distribution. The average total home ranges of wild boars (87.1 ± 17 km2 MCP, 33 ± 5.5 SE km2 95% KDE) were larger compared with studies from southern latitudes. The length of nocturnal activity times varied seasonally. All studied individuals at the border zone (N = 15) showed continuous transboundary movements, with home range core areas located mainly on the Russian side. Wild boar locations were predominantly in the Russia border zone, especially resting sites during the daytime. Most locations in Finland were from night-time feeding excursions. Our study shows that, although home ranges are large, adult wild boars are relatively sedentary also in northern latitudes. However, the movement capacity of the species enables the transboundary spread of diseases such as African swine fever. Our results provide information for risk management and emphasize the importance of transboundary collaboration in the monitoring and management of common wild boar populations.

Biological Uptake, Water Mass Mixing and Scavenging Limit the Transport of Manganese‐Rich Waters From the East Antarctic Shelf

AbstractManganese (Mn) is an essential element involved in photosynthesis, yet its concentrations in Southern Ocean open waters are very low, arising from biological uptake and limited external inputs. At southern latitudes, waters overlying the Antarctic shelf are expected to have much higher Mn concentrations due to their proximity to external sources. In this study, we investigated the potential export of Mn‐rich Antarctic shelf waters toward depleted open Southern Ocean waters. Our results showed that while high Mn concentrations were observed over the shelf, biological uptake decreased dissolved Mn concentrations in surface waters north of the South Antarctic Circumpolar Current Front (&lt;0.1 nmol kg−1), limiting its export. Conversely, mixing between Mn‐rich Antarctic Bottom Waters and Mn‐depleted Lower Circumpolar Deep Waters combined with oxidative and scavenging processes led to a decrease in dissolved Mn concentrations within bottom waters, with distance from the coast. Particulate Mn concentrations also showed a decreasing trend with distance from the coast. A comparison with other Antarctic coastal regions suggests this bottom water Mn removal may be widespread and that East Antarctica may be characterized by lower Mn concentrations compared to other regions. Still, subsurface dissolved Mn maxima (0.3–0.6 nmol kg−1) represented a potential reservoir for surface waters. We hypothesize that these high subsurface values result from external sources near the shelf. Overall, these results suggest that the moderate lateral export of trace metal‐enriched waters contributes to the extremely low and potentially limiting Mn concentrations previously reported further north in this Southern Ocean region.

Comparative Analysis of the conditions for the red tidies development at the Cretaceous–Paleogene boundary of the Stevens Klint and Zumaia sections

The closest mass extinction to present occurred at the Cretaceous–Paleogene Boundary. The article presents the results of a geochemical study of the sections Stevens Klint (Denmark) and Zumaia (Spain). Authors built petrochemical modules (CIA) and indicators which demonstrate differences in the evolution of the environment at the K / T boundary. On the basis of the modern behaviour and development of dinoflagellates, an assumption was made about the possibility of the development of red tides as a chain of catastrophic events at the K / T boundary. It is shown that the conditions of southern latitudes demonstrated the best conditions for the development of red tides and the creation of anoxic zones. While in the northern regions, red tides could only be sporadic and could not be the cause of the biotic crisis that began in the aquatic environment.

Siege in the Southern Stratosphere: Hunga Tonga‐Hunga Ha'apai Water Vapor Excluded From the 2022 Antarctic Polar Vortex

AbstractWe use Aura Microwave Limb Sounder (MLS) trace gas measurements to investigate whether water vapor (H2O) injected into the stratosphere by the Hunga Tonga‐Hunga Ha'apai (HTHH) eruption affected the 2022 Antarctic stratospheric vortex. Other MLS‐measured long‐lived species are used to distinguish high HTHH H2O from that descending in the vortex from the upper‐stratospheric H2O peak. HTHH H2O reached high southern latitudes in June–July but was effectively excluded from the vortex by the strong transport barrier at its edge. MLS H2O, nitric acid, chlorine species, and ozone within the 2022 Antarctic polar vortex were near average; the vortex was large, strong, and long‐lived, but not exceptionally so. There is thus no clear evidence of HTHH influence on the 2022 Antarctic vortex or its composition. Substantial impacts on the stratospheric polar vortices are expected in succeeding years since the H2O injected by HTHH has spread globally.

Komlopteris: A persistent lineage of post-Triassic corystosperms in Gondwana

Komlopteris is a genus that includes the youngest representative of the so-called ‘seed ferns’, an informal group of gymnosperms that were prevalent during the Mesozoic but largely went extinct at the end of the Cretaceous. New fossil material, morphological data, and an extensive literature review allowed us to clarify the systematics of Gondwanan post-Triassic leaves of the Komlopteris lineage that were formerly assigned to diverse genera. Trends in diversity and distribution were identified. Ten species of Komlopteris were recognized in Jurassic to Eocene strata across Gondwana. Earliest records of the genus derive from South America soon after the end-Triassic extinction event. The genus reached its peak diversity and range in the Late Jurassic and Early Cretaceous and declined markedly after the Aptian. Its youngest representation is in mid-Cretaceous to Eocene deposits of southeastern Gondwana. Although never dominant, Komlopteris represents an important subsidiary component of austral Jurassic–Paleogene plant fossil assemblages. Striking morphological similarities to Dicroidium and Kurtziana, and co-occurrence with low concentrations of Alisporites/Falcisporites-type pollen, suggest that Komlopteris was a gymnosperm belonging to Umkomasiales (=Corystospermales) that survived the end-Triassic and end-Cretaceous biotic crises in climatically buffered humid habitats of high southern latitudes. Arthropod induced leaf damage was rare on Komlopteris foliage and recognized only in two Late Jurassic–Early Cretaceous species.

Revision of the stiletto fly genus Medomega Winterton &amp; Lambkin from Australia (Therevidae)

The highly distinctive stiletto fly genus Medomega Winterton &amp; Lambkin, 2012 is revised. Thirteen new species are described including: Medomega badius sp. n.; M. blothrocybe sp. n.; M. ephydropsis sp. n.; M. helvolifrons sp. n.; M. irwini sp. n.; M. karijini sp. n.; M. megasathe sp. n.; M. pilofrons sp. n.; M. prolixa sp. n.; M. propepilofrons sp. n.; M. serpentaria sp. n.; M. smarti sp. n. and M. zonion sp. n. Most species of this genus are found in the western and southern parts of Australia with adults predominantly active during the autumn months in southern latitudes to winter months in northern latitudes.