In arid and semi-arid ecosystems, the duration of vegetation response to rainfall pulses varies with the magnitude and timing of the precipitation event. Extreme weather events, such as tropical cyclones, can trigger long-lasting ecological responses. In this study, we examined the impact of tropical cyclones on ecosystem gross primary production (GPP) in the Pilbara, Western Australia, and identified two distinct effects: direct and legacy effects. Our findings reveal that tropical cyclones delivering substantial rainfall lead to an immediate increase in GPP. This direct effect typically persists for approximately two months. Following this initial GPP increase, the ecosystems exhibit altered responses to subsequent rainfalls, a phenomenon we define as the legacy effect, which lasts for about 100 days. On average, tropical cyclones contribute an additional 30 g C/m 2 /y GPP during a water year, with 40% of this additional GPP attributed to the legacy effect, compared with tropical-cyclone-unaffected areas in the semi-arid tropics of Western Australia. However, prolonged drought can diminish the legacy effect. These findings improve our understanding of how changes in precipitation patterns driven by global climate change may influence carbon assimilation and ecosystem resilience in semi-arid regions. This diagram shows the two stages of tropical cyclone effects and the additional GPP caused by tropical cyclones in the Pilbara basin, tropical Western Australia. During the direct-effect stage, GPP increases due to the immediate rainfall pulse and returns to its pre-TC event level after approximately two months. During the legacy-effect stage, GPP increases due to better conditions caused by tropical cyclone rainfall, including increased deep soil water, larger foliage cover, and enhanced shallow root systems. The tropical cyclone rainfall brings additional 30 g C/m 2 per water year on average. • In addition to the immediate direct effect, tropical cyclones also improve vegetation response to subsequent rainfall (the legacy effect). • The direct effect lasts for ∼two months, and the legacy effect for ∼three months. • The legacy effect is substantiated by foliage cover and shallow roots. • Tropical cyclones contribute 30 g C/m 2 /yr, of which 40% comes from the legacy effect. • Extended droughts can suppress the legacy effect.

Sea urchins are renowned for their capacity to shape shallow reef community structure and function, especially when at high densities. However, most quantitative assessments of urchin densities are based on diurnal surveys, despite the nocturnal emergence of urchins being a well-recognised phenomenon. The value of such diurnal density estimates is, therefore, inherently dependent on the extent of nocturnal urchin emergence and the consistency of this diel behaviour under different contexts. Yet, our understanding of nocturnal urchin emergence under different local conditions at broad scales including between tropical and temperate reefs, remains largely unresolved. Here, we evaluate the extent of nocturnal urchin emergence, and assess how this varied with potential predictors, using paired day and night surveys across a total of 42 reef sites spanning tropical (n=23) and temperate (n=19) Australia. Among kelp-dominated temperate rocky reefs, urchin densities and biomass were ∼7-8-fold greater than observed on tropical coral reefs. Regardless of realm, urchin densities and biomass were consistently higher at night, with tropical reefs showing the greatest diel differences (3.5-fold higher density and 3.0-fold higher biomass) compared to temperate reefs (1.4-fold and 1.7-fold, respectively). Gradient Boosted Regression Trees revealed that mean sea surface temperature (SST) was the strongest predictor of the relative extent of nocturnal urchin emergence, with higher relative emergence on reefs with warmer SST, corresponding with strong patterns in nocturnal emergence peaking toward equatorial latitudes. Our findings show that daytime surveys likely greatly underestimate urchin activity, population size, and ecological impacts, particularly on tropical reefs, with important consequences for reef monitoring and management.

The silver-lipped pearl oyster, Pinctada maxima, is an iconic bivalve farmed in tropical Australia and South-east Asia to produce high valued South Sea pearls. Here, we present a high-quality, chromosome-level reference genome for P. maxima. The final genome assembly has a total size of 1.27 Gb, with a scaffold N50 length of 65.69 Mb. Using high-throughput chromosome conformation capture (Hi-C) technology, we have anchored 80.99% of the assembly to 14 chromosomes. The BUSCO analysis revealed a high level of accuracy and completeness, identifying 87.9% (n = 4,658) of Mollusca core genes, which exceeds the average completeness of 79.2% reported for other mollusc genomes sequenced and annotated to date. The assembly includes 62.79% repeat elements (809 Mb), and gene annotation predicted 25,752 protein-coding genes. This genomic resource offers a powerful tool for unraveling the molecular mechanisms underlying pearl formation and facilitating continued research into the evolutionary biology of pearl oysters worldwide.

In the austral summer of 2021–2022, Australia experienced an unprecedented Japanese encephalitis virus (JEV) outbreak, with detections over 3000 km south of previous occurrences. Given the limited knowledge of JEV transmission ecology in Australia, we developed geospatial models of transmission risk to support the public health response. We created time-varying habitat suitability models for suspected mosquito vectors and ardeid hosts using month-scaled occurrence and covariate data from 2000–2023. Ardeid host presence-absence data were obtained from eBird and BirdLife Australia, with habitat suitability estimated using gradient-boosted regression tree models. A national dataset of Culex occurrences was compiled from mosquito surveillance records, literature, and biodiversity databases. Penalised logistic regression was used to model mosquito vector habitat suitability. Vector and host habitat predictions for the outbreak peak in February 2022 were rescaled using JEV infection locations in the public domain to create a combined habitat suitability surface. Our models aligned with detected JEV infections at the continental scale, highlighting transmission suitability across tropical northern Australia and major inland drainage basins in the East. Unlike existing models, we predicted lower suitability along the eastern seaboard, suggesting a delimiting effect of the Great Dividing Range. Our approach provides the most comprehensive and temporally dynamic models for JEV hosts and vectors in Australia, with a significantly larger vector dataset than previous studies. The novel method of rescaling host and vector outputs into a combined surface offers new insights into JEV transmission risk. Favourable conditions were repeated in 2023 with few detected infections, emphasising that JEV ecology in Australia remains poorly understood. This study’s results can support improvements in arbovirus surveillance systems, promoting earlier detection of circulating viruses. Increased focus on vector ecology and distributions is crucial for better understanding JEV transmission in Australia.

Precipitation bursts in northern Australia with and without preceding heatwaves

Extended periods of cold, wet and windy conditions, known as 'chill events', rapidly increase potential heat loss in livestock. Such events pose substantial risks to cattle, particularly breeds in northern Australia, that are acclimatised and bred for warmer conditions. Yet due to their rarity, very little is known about chill events in tropical climates, particularly during the dry season (May to October). This study provides an observational analysis of two multi-day chill events over Australia's Northern Territory in June 2007 and September 2021; combined, these events caused the deaths of over 700 cattle at two pastoral stations. Here we investigate the meteorological evolution and biometeorological severity of each event using livestock-specific thermal stress indices: the Cattle Comfort Index (CCI) and Livestock Chill Index (LCI). In both events, unusual warmth gave way to extremely cold conditions (CCI < the long-term 1 st percentile), including high to very high LCI values despite the events occurring during the May to October dry season. We find that established LCI absolute thresholds developed for southern sheep do not adequately reflect chill severity in northern cattle systems, underscoring the need for locally derived percentile-based measures. We also present an illustrative example of the early-warning signals for the September 2021 event that could have been produced using the Bureau of Meteorology’s operational numerical weather prediction system ACCESS-G. Several forecast initialisations indicated a shift towards markedly colder conditions up to 8-10 days in advance. Our results highlight the benefit of integrating agri-climatic indices into forecast products and the need to develop region- and species-appropriate chill thresholds for northern Australia livestock. • Examines two major cattle chill events in tropical northern Australia. • Thermal stress indices are used to quantify the severity of the chill events. • Modern weather models can predict these events up to 10 days in advance. • Index-based forecasts can improve livestock risk management and adaptation.

Insects that have thrived in thermally stable tropical forests now face temperature regimes unlike anything in their recent evolutionary history. This research examined behavioural adjustments in four insect orders-Lepidoptera, Coleoptera, Hymenoptera, and Odonata-across five tropical and subtropical sites in northeastern Queensland, Australia, where mean annual temperatures have risen between 0.8 and 2.9 °C since 1990. Field observations and automated sensor arrays recorded diel activity patterns, flight timing, oviposition schedules, and microhabitat selection over 14 consecutive months (June 2023 to July 2024). A total of 9,214 behavioural events were logged for 137 focal species. Scatter plot analysis revealed a significant positive relationship between local temperature increase and phenological advancement: for every 1 °C rise in mean temperature, insect activity peaks shifted an average of 4.7 days earlier (R² = 0.61, p<0.001). Box plot comparisons across the five regions showed that insects in the warmest lowland sites (Daintree, Cape York) exhibited the largest shifts in peak activity timing, with median advances of 17.8 and 19.4 days respectively, compared with 11.3 days at the cooler Atherton Tablelands. Nocturnal Lepidoptera displayed the most pronounced diel redistribution, moving 38.4% of their flight activity from the first three hours after sunset to the pre-dawn period when temperatures were 2.1 °C lower. Odonata, by contrast, showed the least behavioural flexibility, maintaining midday flight peaks even as ambient temperatures exceeded their thermal optimum on 23.7% of observation days. These differential responses correlated with body-size-dependent thermal inertia: larger-bodied species had narrower safety margins and less capacity for rapid behavioural compensation. The schematic framework proposed here links climatic drivers to behavioural responses, ecological consequences, and ecosystem-level outcomes, providing a conceptual template for predicting which insect taxa are most at risk as warming continues across tropical Australia.

Centratherum punctatum Cass, a melittophilous shrub endemic to tropical America and Australia, has spread extensively in warm climate countries and has become an invasive species.This paper presents the first official documentation of this species naturalized outside of cultivation in South Africa.Six populations were recorded along roadsides in two provinces, primarily in Limpopo province and Kwa Zulu Natal.One of these populations was identified by a citizen scientist in South Africa.To prevent the spread of this invasive species, efforts are underway to assess the populations for possible early detection and rapid response programs to eradicate them.

In tropical northern Australia the intersection of workforce shortages, high turnover and geographic location impact workforce sustainability. Inevitably, business leaders find themselves considering how to build workforces within the constraints experienced in tropical regional areas. When it comes to workforce development, the enduring question is about talent acquisition and capability. This study focused on tropical northern Queensland, a region in northern Australia ripe for economic growth, yet impacted by workforce shortages. A rapid review of the literature identified and synthesised publications about workforce development in the region to identify the key workforce development strategies utilised. The literature review identified four overarching themes that characterise workforce development strategies in northern Queensland: individual capability, industry strategies, organisational strategies, and regionalisation. The study concludes that given the changing demographic, technological and societal landscape in the region, a multi-tiered approach is needed. The findings suggest that a workforce development ecosystem could create a path towards workforce sustainability for regional areas negating the internal versus external recruitment, retention and skills development dilemma. Workforce development ecosystems could support ongoing workforce sustainability for business development in the regions with characteristics similar to those of tropical northern Australia.

Lung involvement in patients with leptospirosis is associated with a more complicated disease course. However, the demographic and clinical associations of lung involvement are incompletely defined, and its optimal management is uncertain. This retrospective study examined consecutive patients admitted to a referral hospital in tropical Australia, with laboratory-confirmed leptospirosis between January 2015, and June 2024. Lung involvement was defined as new lung parenchymal changes on chest imaging at any point during the patients’ hospitalisation. The demographics, clinical findings and clinical course of the patients with and without lung involvement were compared. The median (interquartile range (IQR)) age of the 109 patients was 39 (24–56) years; 93/109 (85%) were male. Lung involvement was present in 62/109 (57%), 55 (89%) of whom had no documented comorbidities. Patients with lung involvement received antibiotics later in their disease course than those without lung involvement (after a median (IQR) of 5 (4–6) versus 3 (2–5) days of symptoms, p = 0.001). Lung involvement was frequently associated with multi-organ failure: patients with lung involvement were more likely to require intensive care unit admission than patients without lung involvement (41/62 (66%) versus 15/47 (32%), p < 0.001). Overall, 30/109 (28%) satisfied criteria for acute respiratory distress syndrome (ARDS) and 26/109 (24%) developed pulmonary haemorrhage. Patients with lung involvement received cautious fluid resuscitation, vasopressor support and prompt initiation of additional supportive care—including mechanical ventilation, renal replacement therapy and extracorporeal membranous oxygenation—guided by the patients’ physiological parameters and clinical trajectory. All 109 patients in the cohort were alive 90 days after discharge. Life-threatening lung involvement was identified in the majority of individuals in this cohort and occurred in young and otherwise well individuals. However, in Australia’s well-resourced health system excellent outcomes can be achieved using a standard contemporary approach to the management of a patient with undifferentiated infection while a confirmed diagnosis of leptospirosis is awaited.

Sea level rise is expected to transform coastal aquatic ecosystems world‐wide. The freshwater wetlands of tropical northern Australia are among the most biodiverse and productive ecosystems on the continent, but owing to high regional rates of sea level rise coupled with low‐lying land and large tides they are increasingly affected by saltwater intrusion. The propagule bank, including seeds of aquatic primary producers and eggs of aquatic invertebrates, stored in wetland sediments is vital for the establishment of ecological communities, and ultimately to primary and secondary production. This experimental study examined the impact of increasing salinity on emergence of primary producers and invertebrates from sediment cores collected from tropical freshwater wetlands between Darwin and Kakadu National Park in northern Australia. Sediment cores (n = 216) were placed in microcosms and inundated with one of four salinity treatments: 0 ppt (freshwater/control); 7 ppt; 16 ppt and 35 ppt (sea water) and decanted on approximately days 10, 20 and 90. In comparison to freshwater controls, median chlorophyll a of phytoplankton and benthic algae declined sharply with increasing salinity, and in the highest salinity treatment were reduced by 93% and 60% respectively. Macrophyte biomass, aquatic invertebrate density and richness were reduced to near zero in all salinity treatments. Increasing salinity decreases the abundance of primary producers and aquatic invertebrates that emerge from sediment cores in seasonally inundated tropical freshwater wetlands. Macrophyte emergence exhibits no tolerance to salinities above freshwater (0 ppt) and aquatic invertebrate emergence declines rapidly in both abundance and diversity as salinity increases. Our results suggest that freshwater aquatic primary producers and aquatic invertebrates will be severely impacted by sea level rise and saltwater intrusion. Reduced freshwater aquatic primary production and aquatic invertebrates may have important implications for food webs, and other social and biodiversity values of tropical freshwater wetlands.

Local thunderstorms are among the major meteorological hazards in the Australian region. These storms inherently have compound impacts, including hail, flash floods, and wind gusts, and consistently cause some of the highest insured losses. Studies on the climate change impact on local storms face the challenges of unreliable storm climatology and uncertainties in the numerical modeling of physical processes. In this study we have adopted an approach to examining the ingredients of severe storm development based on regional climate simulations. We examined two generations of NARCliM datasets (NSW and Australian Regional Climate Modeling). Projected changes in convective indices for the latter half of the twenty-first century indicate an environment more conducive to thunderstorm development, primarily due to enhanced atmospheric instability, despite a concurrent increase in convective inhibition. A measure that combines the dynamic factor of vertical wind shear further shows that the potential storm days will increase substantially, such as a doubling of days with storms during summer, under the influence of climate change over tropical, eastern, and southeastern Australia. The storm season in a year is also expected to elongate. These projections imply increasing thunderstorm-related hazards in the future, including hail, flood, and high winds.

ABSTRACT Intact riparian vegetation plays an important role in the energetics of freshwater ecosystems. Plant and animal biomass from the riparian zone may be directly consumed by freshwater organisms without intermediary processing by microbial or metazoan communities. This study examined the extent and importance of such direct consumption by Australian freshwater fishes. We assembled a data set that spanned the Australian continent and examined the extent of terrestrial contributions to freshwater fish diets for 137 species (i.e., approximately one half of Australia's fish fauna). Using a range of multivariate methods we examined variation in reliance on terrestrial material (leaves, fruit, invertebrates and vertebrates) between species and families and between different regions of Australia, particularly focussing on differences between temperate and tropical Australia. We also examined whether particular aspects of morphology were related to increased consumption of terrestrially‐derived material. Overall, terrestrial invertebrates contributed 10% or more of the diet of about one quarter of all species and families examined. Most families contained at least one species for which consumption of terrestrial invertebrates was high (&gt; 20%) but only two families, Galaxiidae and Melanotaeniidae, exhibited consistently high consumption across most species. Terrestrial vegetation, principally fruit, contributed 10% or more of the diet in three species from two families only (Terapontidae and Ariidae). There was little regional variation in reliance on terrestrial invertebrates as a food source, but species in south‐western Western Australia consistently consumed more than did species elsewhere. Frugivory, in contrast, was significantly more common in the wet‐dry tropical northern Australia as reported elsewhere for other tropical regions. Australian freshwater fishes appear to rely more on terrestrial invertebrates than do freshwater fishes elsewhere although data is largely lacking to make broader comparisons with other continents. Morphological correlates with the consumption of terrestrial material were individually and collectively limited, but species with a pelagic habit and an upturned (supraterminal) mouth consumed significantly more such material than did species within other habit/mouth orientation combinations. The present study further confirms the importance of the riparian zone to lotic ecosystem function with direct contributions of terrestrially derived material contributing significantly to the diet of many species and of some families in particular. Although data is lacking for large‐scale (i.e., continental) assessments of the importance of terrestrial subsidies to aquatic food webs elsewhere, riparian inputs appear especially important in the Australian context and especially in regions characterised by low primary productivity. Loss or degradation of riparian vegetation can pose a threat to freshwater fishes at a variety of spatial scales. The present study provides a baseline for further studies of the importance of terrestrially‐derived material at large spatial scales.

Burkholderia pseudomallei, Staphylococcus aureus and Escherichia coli are common causes of bacteraemia in the tropical Asia Pacific region. The 28-day mortality rate of B. pseudomallei bacteraemia in Thailand has been reported to be 66%, higher than the 28-day mortality rate of bacteraemia due to S. aureus (43%) and E. coli (19%) in that country. Individuals living in rural and remote locations in these Thai studies had an even poorer prognosis. The mortality rates of individuals with bacteraemia due to B. pseudomallei, S. aureus and E. coli in countries with well-resourced health systems like Australia have not been compared directly. We examined all cases of bacteraemia due to B. pseudomallei (between 2016 and 2022) and S. aureus and E. coli (between 2016 and 2020) in the Far North Queensland region of tropical Australia. We compared the characteristics and clinical course of these patients. We also examined the contribution of age, gender, comorbidity, remote residence and First Nations Australian status to the patients' 30-day mortality. In total there were 177 (10.1%) episodes of bacteraemia due to B. pseudomallei, 601 (34.3%) due to S. aureus and 974 (55.6%) due to E. coli. Individuals with B. pseudomallei bacteraemia were younger than individuals with bacteraemia due to the other pathogens (median (interquartile range) age: 58 (47-67) versus 65 (49-77), p < 0.0001), they were less likely to live remotely (67/177 (37.9%) versus 730/1575 (46.4%), p = 0.03) and they did not have a greater rate of severe comorbidity (Charlson Comorbidity Index ≥ 5; 59/177 (33.3%) versus 624/1572 (39.7%), p = 0.10). There were 133/1752 (7.6%) who died within 30 days, which included 19/177 (10.7%) with B. pseudomallei bacteraemia, 62/601 (10.3%) with S. aureus bacteraemia and 52/974 (5.3%) with E. coli bacteraemia. In multivariate analysis that included all 5 pre-specified patient characteristics, the year of presentation and the 3 pathogens (with E.coli as the reference), B. pseudomallei bacteraemia (hazard ratio (HR) (95% confidence interval (CI): 2.52 (1.48-4.31), p = 0.001), S. aureus bacteraemia (HR (95% CI): 2.47 (1.69-3.59), p < 0.0001), severe comorbidity (HR (95% CI): 2.53 (1.66-3.85), p < 0.0001) and age (divided by 10) (HR (95% CI): 1.19 (1.06-1.34), p = 0.001) were independently associated with a higher 30-day mortality, while a rural/remote presentation (HR (95% CI): 0.53 (0.37-0.78), p = 0.001) was independently associated with a lower 30-day mortality. Among patients with B. pseudomallei bacteraemia, there was no association between any other of the pre-specified patient factors and 30-day mortality. A well-resourced hub and spoke model of health care was able to minimise the 30-day mortality of individuals with B. pseudomallei, S. aureus and E. coli bacteraemia in this region of remote tropical Australia. However, B. pseudomallei bacteraemia had a higher 30-day mortality than bacteraemia due to S. aureus or E. coli, highlighting the lethal potential of the organism.

Tropical rock oyster aquaculture is an emerging industry for most countries in the Asia-Pacific, including tropical north Australia. Food safety is an important element, but there exist large gaps in our understanding of the risks posed by potential pathogens including virulent Vibrio strains. To start to address this, oysters were collected from 13 sites across northern Australia to measure their bacterial community, including Vibrio. The dominant bacterial families were the Spirochaetaceae, Mycoplasmataceae and Vibrionaceae. The most abundant Vibrio species were V. parahaemolyticus, V. harveyi and V. diabolicus, but other potential human pathogenic species were detected including V. vulnificus. V. parahaemolyticus levels were above recommended guidelines in 37% of oysters but virulence genes trh or tdh were not detected; V. vulnificus was detected in 31% of oyster samples. Eleven potential oyster Vibrio pathogens were identified. Our results show that although food safety Vibrio species were prevalent, virulence genes were not. This highlights the need to focus on virulence rather than species abundance to obtain a realistic measure of risk.

The highly promising species Tridax procumbens produces secondary metabolites that are said to have a number of medical applications, such as anesthetic, anti-inflammatory, anti-diabetic, and anti-anemic effects etc. Many communities have traditionally used this species in traditional ways. Tridax procumbens is a unique member of the Asteraceae family. Naturally occurring in tropical Africa, Asia, and Australia, the plant is native to tropical America. The locals name it "Ghamara," which is also known as "coat buttons" in English. Some Ayurvedic practitioners prescribe it as "Bhringraj." Alkaloids, carotenoids, flavonoids (catechin and flavones), fumeric acid, fl-sitosterol, saponins, and tannins were all found throughout the phytochemical screening. Pharmacologically, Tridax procumbens is well known for its antioxidant, hepatoprotective, antiviral, wound-healing, insecticidal, antidiabetic, hypotensive, immunomodulating, bronchial catarrh, dysentery, diarrhea, and prevention of hair loss by promoting hair growth. It also has antimicrobial activity against both gram-positive and gram-negative bacteria, anti-cancer, anti-inflammatory, and antitubercular properties. This review is attempts to present phytochemical &amp; pharmacologically use, significance of Tridax procumbens to treat, prevent the acute &amp; chronic diseases, and also present Pharmacognostic and phytochemical investigation of Tridax procumbence plant.

Vibrio parahaemolyticus is an autochthonous marine bacterium that causes gastroenteritis after ingestion of raw or undercooked seafood and, less frequently, wound and tissue infections. Genomic information from northern Australia is scarce, and most sequences to date stem from foodborne outbreaks in southern states. We analysed 24 environmental and 5 clinical isolates (4 wound and 1 gastrointestinal case) collected in the wet-dry tropics from northern Australia and placed them alongside 48 representative public genomes. Core-genome phylogeny showed that the northern Australian strains sit within the broad VppAsia lineage and intermix with Asian and South American isolates, reflecting the limited geographic structuring in the marine environment. A gastrointestinal isolate (RDH3, ST-2901) harboured the trh2-positive VPaI-β pathogenicity island (including vtrAB and hlyDBAC genes) and displayed an A187S change in the TRH2 toxin which was absent in the other TRH-1/-2 sequences of the isolates analysed in this study. Wound isolates lacked tdh and trh genes, suggesting that the species' intrinsic virulome may suffice for tissue colonization; notably, one wound strain carried a plasmid with a Vibrio alginolyticus pilT copy linked to twitching motility which has been associated with wound infections. It remains to be determined whether this additional pilT copy, beyond the core genome copies, confers a selective advantage for tissue colonization. Plasmid diversity amongst clinical isolates and a diseased aquaculture fish, including a putative chimaera plasmid in the gastrointestinal isolate, underscores the role of mobile elements as reservoirs allowing adaptability to changing environments. Our findings expand the Australian genomic catalogue beyond outbreak strains, reveal extensive accessory-genome variability in tropical waters and underscore the need for One-Health surveillance frameworks that monitor virulence and resistance markers beyond the canonical hemolysin genes.

Abstract Eriocaulon is a diverse genus with over 400 species worldwide. It exhibits its highest diversity in tropical regions and Australia accounts for 34 species. Eriocaulon species are found predominantly in the northern region of Australia, with a few extending to central Australia's arid and semiarid artesian springs and temperate areas. This study aims to elucidate species relationships and address species complexes, specifically the E. cinereum complex and the complex associated with E. nanum , E. athertonense , and E. scariosum . To achieve this, we expand on a previous phylogenetic study of Eriocaulon that focused mostly on African and Asian species using one nuclear and three chloroplast DNA regions, adding multiple accessions of all recognized Australian species and species from other continents. Our analysis identified seven major clades, with none found to be endemic to Australia. Our data were not able to fully resolve the E. cinereum complex, which is primarily composed of nonmonophyletic groupings of E. cinereum accessions and exhibits a substantial polytomy but also includes E. australasicum , E. rivicola , and E. scullionii . Our study also found that E. carsonii is not directly related to E. giganticum and E. aloefolium , despite their sympatry and similarities in an isolated semi‐arid spring wetland. Furthermore, all major Australian clades were found to be sister to Asian taxa, suggesting multiple dispersal events between Australia and other landmasses. This study provides evidence for the monophyly of most taxa, highlights the impact of Asian species on the evolutionary history of Eriocaulon in Australia and identifies several previously unknown species.

Fact box Species 6 six species of Vitex have been recognized in India which include V. negundo, V. glabrata, V. leucoxylon, V. penduncularis, V. pinnata, and V. trifolia (Kulkarni, 2011). Family Lamiaceae (Verbenaceae) Common names Chinese chaste tree, Nirgundi, Five-Leaf Chaste Tree, Sinduvara, Indrani, Nilanirgundi, local name Banah. Distribution Widely distributed throughout the world in the tropical and subtropical regions of Australia, Asia, Africa, with a few South American species. It occurs in Kenya, Tanzania, Mozambique, Madagascar (in Africa), and in Afghanistan, Bangladesh, Bhutan, Cambodia, China, India, Indonesia, Malaysia, Myanmar, Nepal, Pakistan, Philippines, Sri Lanka, Thailand, Taiwan and Vietnam (in Asia). It is also found in similar habitats along the seashore throughout Mauritius, Japan and southward through Malaya to tropical Australia and Polynesia. Flowering period April to October. Values to bees It is widely planted as a hedge-plant along the roads and between the fields that serves as an important bee forage plant. Pollen and Nectar Good source of nectar and pollen. Pollinators have been of special concern in recent years. The attractiveness of Vitex cultivars to both honey bees and bumble bees, as well as other pollinators, is an important study as part of an urban landscape designed to support pollinators. Honey Vitex honey, also known as chaste tree honey, is a light amber, transparent honey with a delicate fragrance. It is considered a monofloral honey and possesses distinctive qualities compared to other types. It is particularly recognized for its unique chemical profile, with a higher concentration of certain phenolic compounds and flavonoids that contribute to its strong antioxidant activity. Moreover, Vitex honey generally contains more proline and may exhibit a different mineral composition when compared with other honeys such as acacia, linden, rape, or jujube honey. V. negundo honey is traditionally also used as medicine for bronchitis and other respiratory diseases and is known to improve digestion (Vishwanathan & Basavaraju, 2010). Other uses It is used as a hedge, ornamental plant, growth promoter in agriculture, manure, pesticide, medicine, food, food protectant, household pesticide, in reclamation of wasteland and erosion, basketry, and in the preparation of grain storage structures. All parts of V. negundo, including leaves, flowers, twigs, roots, and seeds, have been commonly used for various applications in folk medicine. Both leaves and seeds have also been claimed to possess edible purposes, being occasionally used as a condiment and tea, and even as a famine food when all else fails. The essential oils from leaves and seeds have fantastic insecticide and antibacterial effects against food infestation and bacteria contamination, making VN oil an ideal food protectant to facilitate food preservation. In India, nirgundi is considered a sacred plant and used in different religious rituals.

Group A Streptococcus (GAS) bacteraemia is common in tropical settings and has a high case-fatality rate. Early recognition of the high-risk patient can expedite the escalation of care. We examined consecutive episodes of GAS bacteraemia in Far North Queensland, tropical Australia between January 1, 2014, and December 31, 2020. The patients' demographics and clinical and laboratory indices at presentation were correlated with their subsequent clinical course. There were 286 episodes of GAS bacteraemia. The patients' median (interquartile range) age at presentation was 60 (48-71) years, 154 (53.9%) were male, 169 (59.1%) identified as a First Nations Australian, 126 (44.1%) had severe comorbidity and 136 (47.6%) lived in a remote location. There were 50/286 (17.5%) who died or were admitted to the intensive care unit (ICU) admission within 30 days of hospitalisation. In multivariable analysis, systolic blood pressure <100 mmHg (adjusted odds ratio (aOR) (95% confidence interval (CI)): 5.67 (2.20 - 14.55), p<0.0001), serum lactate >4 mmol/L (aOR (95% CI)): 5.32 (1.92 - 14.72), p=0.001), a circulating lymphocyte count <0.5×109/L (aOR (95% CI)): 2.68 (1.17 - 6.12) p=0.02) and a serum albumin <30 g/L (aOR (95% CI)): 2.24 (1.01 - 4.97), p= 0.049) at presentation were independent predictors of death or ICU admission within 30 days. There were 21/286 (7%) with a diagnosis of streptococcal toxic shock syndrome (STSS) and necrotising fasciitis; all 21 died or required ICU admission. Individuals with a diagnosis of STSS and/or necrotising fasciitis were more likely to die within 30 days than the individuals without STSS or necrotising fasciitis (8/21 (38.1%) versus 13/272 (4.8%), OR (95%): 26.56 (8.03 - 87.86), p < 0.0001). Patients with GAS bacteraemia who have hypotension, raised serum lactate, lymphopenia and hypoalbuminaemia at presentation are at greater risk of a complicated course. Individuals with STSS and necrotising fasciitis are at the greatest risk of death, emphasising the importance of considering - and actively excluding - these diagnoses in the appropriate clinical context.