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As historically described, the genus Amphidinum has long been recognized to be polyphyletic. Amphidinium sensu lato is the most diverse of all marine benthic dinoflagellate genera and after the redefinition of the sensu stricto genus about 100 species remained of unknown generic affiliation. A species similar to the Australian sensu lato species Amphidinium boggayum was discovered in France. Morphological and molecular phylogenetic data supported the description of a new species and the classification of the two closely related species within a new athecate, photosynthetic, benthic genus, named Bindiferia. Cells were dorsoventrally flattened with smaller asymmetric epicone. The cingulum was descending. The sulcus reached the antapex and had an extension onto the epicone. The apical structure complex formed an anticlockwise loop around the apex. A red stigma was located in the anterior part of the epicone, near the apex. Vegetative division occurred in a non-motile stage within a hyaline sheath. Non-motile cells had dorsal hypocone grooves. The two species differed from each other in epicone size, cingulum displacement, nucleus location and surface groove occurrence. The molecular phylogenetic results showed that Bindiferia is a distinct taxon that is only distantly related to Amphidinium sensu stricto. The nearest sister group to Bindiferia could not be reliably determined, but the apical structure complex suggested a close relationship to the genera of the Gymnodinium sensu stricto clade.

Genetic diversity in marine microbial eukaryotic populations (protists) drives their ecological success by enabling diverse phenotypes to respond rapidly to changing environmental conditions. Despite enormous population sizes and lack of barriers to gene flow, genetic differentiation that is associated with geographic distance, currents, and environmental gradients has been reported from planktonic protists. However, for benthic protists, which have reduced dispersal opportunities, phylogeography and its phenotypic significance are little known. In recent years, the East Australian Current (EAC) has intensified its southward flow, associated with the tropicalization of temperate waters. Benthic harmful algal species have been increasingly found in south‐eastern Australia. Yet little is known about the potential of these species to adapt or extend their range in relation to changing conditions. Here, we examine genetic diversity and functional niche divergence in a toxic benthic dinoflagellate, Ostreopsis cf. siamensis, along a 1,500 km north–south gradient in southeastern Australia. Sixty‐eight strains were established from eight sampling sites. The study revealed long‐standing genetic diversity among strains established from the northern‐most sites, along with large phenotypic variation in observed physiological traits such as growth rates, cell volume, production of palytoxin‐like compounds, and photophysiological parameters. Strains from the southern populations were more uniform in both genetic and functional traits, and have possibly colonized their habitats more recently. Our study reports significant genetic and functional trait variability in a benthic harmful algal species, indicative of high adaptability, and a possible climate‐driven range extension. The observed high trait variation may facilitate development of harmful algal blooms under dynamic coastal environmental conditions., Genetic diversity and phenotypic diversity in marine microbial eukaryotic populations are critical for adaptability, range expansion, and potential bloom formation. In this study, we report significant functional trait variability in a benthic harmful algal species, indicative of high adaptability, and a possible climate‐driven range extension along the East Australian Current region in the South Pacific. The observed high trait variation may facilitate development of harmful algal blooms under dynamic coastal environmental conditions.

Despite their relatively high thermal optima (T-opt), tropical taxa may be particularly vulnerable to a rising baseline and increased temperature variation because they live in relatively stable temperatures closer to their T-opt. We examined how microbial eukaryotes with differing thermal histories responded to temperature fluctuations of different amplitudes (0 control, +/- 2, +/- 4 degrees C) around mean temperatures below or above their T-opt. Cosmopolitan dinoflagellates were selected based on their distinct thermal traits and included two species of the same genus (tropical and temperate Coolia spp.), and two strains of the same species maintained at different temperatures for >500 generations (tropical Amphidinium massartii control temperature and high temperature, CT and HT, respectively). There was a universal decline in population growth rate under temperature fluctuations, but strains with narrower thermal niche breadth (temperate Coolia and HT) showed similar to 10% greater reduction in growth. At suboptimal mean temperatures, cells in the cool phase of the fluctuation stopped dividing, fixed less carbon (C) and had enlarged cell volumes that scaled positively with elemental C, N, and P and C:Chlorophyll-a. However, at a supra-optimal mean temperature, fixed C was directed away from cell division and novel trait combinations developed, leading to greater phenotypic diversity. At the molecular level, heat-shock proteins, and chaperones, in addition to transcripts involving genome rearrangements, were upregulated in CT and HT during the warm phase of the supra-optimal fluctuation (30 +/- 4 degrees C), a stress response indicating protection. In contrast, the tropical Coolia species upregulated major energy pathways in the warm phase of its supra-optimal fluctuation (25 +/- 4 degrees C), indicating a broadscale shift in metabolism. Our results demonstrate divergent effects between taxa and that temporal variability in environmental conditions interacts with changes in the thermal mean to mediate microbial responses to global change, with implications for biogeochemical cycling.

Diarrhetic shellfish toxins produced by certain species of the marine dinoflagellate Dinophysis can accumulate in shellfish in high concentrations, representing a significant food safety issue worldwide. This risk is routinely managed by monitoring programs in shellfish producing areas, however the methods used to detect these harmful marine microbes are not usually automated nor conducted onsite, and are often expensive and require specialized expertise. Here we designed a quantitative real-time polymerase chain reaction (qPCR) assay based on the ITS-5.8S ribosomal region of Dinophysis spp. and evaluated its specificity, efficiency, and sensitivity to detect species belonging to this genus. We designed and tested twenty sets of primers pairs using three species of Dinophysis - D. caudata, D. fortii and D. acuminata. We optimized a qPCR assay using the primer pair that sufficiently amplified each of the target species (Dacu_11F/Dacu_11R), and tested this assay for cross-reactivity with other dinoflagellates and diatoms in the laboratory (11 species) and in silico 8 species (15 strains) of Dinophysis, 3 species of Ornithocercus and 2 species of Phalacroma. The qPCR assay returned efficiencies of 92.4% for D. caudata, 91.3% for D fortii, and 91.5% for D. acuminata, while showing no cross-reactivity with other phytoplankton taxa. Finally, we applied this assay to a D. acuminata bloom which occurred in an oyster producing estuary in south eastern Australia, and compared cell numbers inferred by qPCR to those determined by microscopy counts (max abund. ∼6.3 × 10

The IPCC Special Report on Global Warming of 1.5 °C highlights the potential for dietary shifts to reduce greenhouse gas emissions from livestock. Reductions in the consumption of terrestrial animal protein require increases in the consumption of other food categories, to maintain food security, balanced dietary patterns, and protein intake. Aquaculture has long been suggested as one way to meet future food security needs, and marine and estuarine aquaculture in particular is associated with comparatively low greenhouse gas emissions. However, marine and freshwater aquaculture is affected by factors including harmful algal blooms (HABs), which have been increasingly documented around the world, correlated to increases in worldwide aquaculture. In this study, we applied a global multi-region input-output model to capture the direct effects as well as the indirect and induced effects HABs might pose to a global dietary transition from terrestrial livestock to increased seafood consumption from marine and estuarine aquaculture sources. We found that marine and estuarine aquaculture has a substantial potential to replace meat consumption from terrestrial livestock sources, as increases in CO2 emissions from aquaculture were more than offset by reductions in emissions from mainly cattle grazing and associated land clearing. HABs were found to have a minor monetary impact, but the impact on protein supply was found to be potentially sizeable. For example, in a future setting where 40% of terrestrial protein sources were replaced by aquaculture, a HAB-caused global loss of 5% would set in motion numerous supply-chain cascades, affecting industries auxiliary to aquaculture, indirectly and ultimately reducing protein intake by 10–20%. Such reductions have the potential for pushing parts of Sub-Saharan populations into protein-energy malnutrition. Nevertheless, there remains a significant potential for a dietary transition to increased aquaculture seafood to contribute to reductions in GHG.

Rapid methods for the detection of biotoxins in shellfish can assist the seafood industry and safeguard public health. Diarrhetic Shellfish Toxins (DSTs) are produced by species of the dinoflagellate genus Dinophysis, yet the comparative efficacy of their detection methods has not been systematically determined. Here, we examined DSTs in spiked and naturally contaminated shellfish–Sydney Rock Oysters (Saccostrea glomerata), Pacific Oysters (Magallana gigas/Crassostrea gigas), Blue Mussels (Mytilus galloprovincialis) and Pipis (Plebidonax deltoides/Donax deltoides), using LC-MS/MS and LC-MS in 4 laboratories, and 5 rapid test kits (quantitative Enzyme-Linked Immunosorbent Assay (ELISA) and Protein Phosphatase Inhibition Assay (PP2A), and qualitative Lateral Flow Assay (LFA)). We found all toxins in all species could be recovered by all laboratories using LC-MS/MS (Liquid Chromatography—tandem Mass Spectrometry) and LC-MS (Liquid Chromatography—Mass Spectrometry), however, DST recovery at low and mid-level concentrations (&lt, 0.1 mg/kg) was variable (0–150%), while recovery at high-level concentrations (&gt, 0.86 mg/kg) was higher (60–262%). While no clear differences were observed between shellfish, all kits delivered an unacceptably high level (25–100%) of falsely compliant results for spiked samples. The LFA and the PP2A kits performed satisfactorily for naturally contaminated pipis (0%, 5% falsely compliant, respectively). There were correlations between spiked DSTs and quantitative methods was highest for LC-MS (r2 = 0.86) and the PP2A kit (r2 = 0.72). Overall, our results do not support the use of any DST rapid test kit as a stand-alone quality assurance measure at this time.

8 pages, 2 tables, A recently published study analyzed the phylogenetic relationship between the genera Centrodinium and Alexandrium, confirming an earlier publication showing the genus Alexandrium as paraphyletic. This most recent manuscript retained the genus Alexandrium, introduced a new genus Episemicolon, resurrected two genera, Gessnerium and Protogonyaulax, and stated that: “The polyphyly [sic] of Alexandrium is solved with the split into four genera”. However, these reintroduced taxa were not based on monophyletic groups. Therefore this work, if accepted, would result in replacing a single paraphyletic taxon with several non-monophyletic ones. The morphological data presented for genus characterization also do not convincingly support taxa delimitations. The combination of weak molecular phylogenetics and the lack of diagnostic traits (i.e., autapomorphies) render the applicability of the concept of limited use. The proposal to split the genus Alexandrium on the basis of our current knowledge is rejected herein. The aim here is not to present an alternative analysis and revision, but to maintain Alexandrium. A better constructed and more phylogenetically accurate revision can and should wait until more complete evidence becomes available and there is a strong reason to revise the genus Alexandrium. The reasons are explained in detail by a review of the available molecular and morphological data for species of the genera Alexandrium and Centrodinium. In addition, cyst morphology and chemotaxonomy are discussed, and the need for integrative taxonomy is highlighted, Support to DMA from the NOAA ECOHAB program (Grant #NA15NOS4780181) is gratefully acknowledged. Support to EG, AR, NS from the COPAs project (CTM2017-86121-R) is acknowledged. IGL and CJBS are COFFA-IPN and EDI-IPN fellows, With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

IntroductionFamilies living in extreme poverty require interventions to support early-childhood development (ECD) due to broad risks. This longitudinal cluster randomised trial examines the effectiveness of Sugira Muryango (SM), a home-visiting intervention linked to Rwanda’s social protection system to promote ECD and reduce violence compared with usual care (UC).MethodsFamilies with children aged 6–36 months were recruited in 284 geographical clusters across three districts. Cluster-level randomisation (allocated 1:1 SM:UC) was used to prevent diffusion. SM was hypothesised to improve child development, reduce violence and increase father engagement. Developmental outcomes were assessed using the Ages and Stages Questionnaire (ASQ-3) and the Malawi Development Assessment Tool (MDAT) and anthropometric assessments of growth. Violence was assessed using questions from UNICEF Multiple Indicators Cluster Survey (MICS) and Rwanda Demographic and Health Surveys (DHS). Father engagement was assessed using the Home Observation for Measurement of the Environment. Blinded enumerators conducted interviews and developmental assessments.ResultsA total of 541 SM families and 508 UC families were enrolled and included in the analyses. Study attrition (2.0% children; 9.6% caregivers) was addressed by hot deck imputation. Children in SM families improved more on gross motor (d=0.162, 95% CI 0.065 to 0.260), communication (d=0.081, 95% CI 0.005 to 0.156), problem solving (d=0.101, 95% CI 0.002 to 0.179) and personal-social development (d=0.096, 95% CI −0.015 to 0.177) on the ASQ-3. SM families showed increased father engagement (OR=1.592, 95% CI 1.069 to 2.368), decreased harsh discipline (incidence rate ratio, IRR=0.741, 95% CI 0.657 to 0.835) and intimate partner violence (IRR=0.616, 95% CI:0.458 to 0.828). There were no intervention-related improvements on MDAT or child growth.ConclusionSocial protection programmes provide a means to deliver ECD intervention.Trial registration numberNCT02510313.

© 2020 Japanese Society of Phycology Certain species of the marine diatom genus Pseudo-nitzschia are responsible for the production of the domoic acid (DA), a neurotoxin that can bioaccumulate in the food chain and cause amnesic shellfish poisoning (ASP) in animals and humans. This study extends our knowledge by reporting on the first observation of the potentially toxic species Pseudo-nitzschia simulans from this region. One clonal strain of P. simulans was isolated from the East Australian Current and characterized using light and transmission electron microscopy, and phylogenetic analyses based on regions of the internal transcribed spacer (ITS) and the D1–D3 region of the large subunit (LSU) of the nuclear-encoded ribosomal deoxyribonucleic acid (rDNA), as well as examined for DA production as measured by liquid chromatography–mass spectrometry. Although this strain was non-toxic under the defined growth conditions, the results unambiguously confirmed that this isolate is the potentially toxic species P. simulans – the first report of this species from the Southern Hemisphere.

Different clades belonging to the cosmopolitan marine diatom Pseudo-nitzschia pungens appear to be present in different oceanic environments, however, a ‘hybrid zone’, where populations of different clades interbreed, has also been reported. Many studies have investigated the sexual reproduction of P. pungens, focused on morphology and life cycle, rather than the role of sexual reproduction in mixing the genomes of their parents. We carried out crossing experiments to determine the sexual compatibility/incompatibility between different clades of P. pungens, and examined the genetic polymorphism in the ITS2 region. Sexual reproduction did not occur only between clades II and III under any of experimental temperature conditions. Four offspring strains were established between clade I and III successfully. Strains established from offspring were found interbreed with other offspring strains as well as viable with their parental strains. We confirmed the hybrid sequence patterns between clades I and III and found novel sequence types including polymorphic single nucleotide polymorphisms (SNPs) in the offspring strains. Our results implicate that gene exchange and mixing between different clades are still possible, and that sexual reproduction is a significant ecological strategy to maintain the genetic diversity within this diatom species.

In 2016, 2017 and 2018, elevated levels of the species Alexandrium pacificum were detected within a blue mussel (Mytilus galloprovincialis) aquaculture area at Twofold Bay on the south coast of New South Wales, Australia. In 2016, the bloom persisted for at least eight weeks and maximum cell concentrations of 89,000 cells L&minus, 1 of A. pacificum were reported. The identity of A. pacificum was confirmed using molecular genetic tools (qPCR and amplicon sequencing) and complemented by light and scanning electron microscopy of cultured strains. Maximum reported concentrations of paralytic shellfish toxins (PSTs) in mussel tissue was 7.2 mg/kg PST STX equivalent. Elevated cell concentrations of A. pacificum were reported along the adjacent coastal shelf areas, and positive PST results were reported from nearby oyster producing estuaries during 2016. This is the first record of PSTs above the regulatory limit (0.8 mg/kg) in commercial aquaculture in New South Wales since the establishment of routine biotoxin monitoring in 2005. The intensity and duration of the 2016 A. pacificum bloom were unusual given the relatively low abundances of A. pacificum in estuarine and coastal waters of the region found in the prior 10 years.

Background Sugira Muryango is a father-engaged early child development and violence-prevention home-visiting programme delivered by trained lay workers. This cluster-randomised trial evaluates whether families living in extreme poverty (Ubudehe 1, the poorest category in the Government of Rwanda’s wealth ranking) who receive Sugira Muryango in combination with a government-provided social protection programme demonstrate greater responsive, positive caregiving, nutrition, care seeking, hygiene, and father involvement compared with control families receiving usual care (UC). Methods Using detailed maps, we grouped closely spaced villages into 284 geographic clusters stratified by the type of social protection programmes operating in the village clusters; 198 clusters met all enrolment criteria. Sugira Muryango was delivered to n = 541 families in 100 treatment clusters with children aged 6–36 months living in extreme poverty. We assessed changes in outcomes in intervention and n = 508 UC control families using structured surveys and observation. Analyses were intent to treat using mixed models to accommodate clustering. Results Families receiving Sugira Muryango improved on core outcomes of parent-child relationships assessed using the Home Observation for Measurement of the Environment (Cohen’s d = 0.87, 95% CI: 0.74, 0.99) and the Observation of Mother-Child Interaction (Cohen’s d = 0.29, 95% CI: 0.17, 0.41). We also saw reductions in harsh discipline on items from the UNICEF MICS (OR = 0.30: 95% CI: 0.19, 0.47) and in violent victimisation of female caregivers by their partners (OR = 0.49, 95% CI: 0.24, 1.00) compared with UC. Moreover, children in families receiving SM had a 0.45 higher increase in food groups consumed in the past 24 h (Cohen’s d = 0.35, 95% CI: 0.22, 0.47), increased care seeking for diarrhoea (OR = 4.43, 95% CI: 1.95, 10.10) and fever (OR = 3.28, 95% CI: 1.82, 5.89), and improved hygiene behaviours such as proper treatment of water (OR = 3.39, 95% CI: 2.16, 5.30) compared with UC. Finally, Sugira Muryango was associated with decreased caregiver depression and anxiety (OR = 0.58, 95% CI: 0.38, 0.88). Conclusions Sugira Muryango led to improvements in caregiver behaviours linked to child development and health as well as reductions in violence. Trial registration ClinicalTrials.gov number NCT02510313.

© 2017 Elsevier B.V. Two isolates of a new tropical, epiphytic dinoflagellate species, Gambierdiscus honu sp. nov., were obtained from macroalgae sampled in Rarotonga, Cook Islands, and from North Meyer Island, Kermadec Islands. Gambierdiscus honu sp. nov. had the common Gambierdiscus Kofoidian plate formula: Po, 3′, 6″, 6C?, 6 or 7S, 5‴, 1p and 2⁗. The characteristic morphological features of this species were its relatively small short dorsoventral length and width and the shape of individual plates, in particular the combination of the hatchet-shaped 2′ and pentagonal 3′ plates and the length to width ratio of the antapical 1p plate. The combination of these characteristics plus the smooth thecal surface and equal sized 1⁗ and 2⁗ plates differentiated this species from other Gambierdiscus species. The phylogenetic analyses supported the unique description. Both isolates of G. honu produced the putative maitotoxin (MTX)-3 analogue, but neither produced ciguatoxin (CTX) or MTX. Extracts of G. honu were shown to be highly toxic to mice by intraperitoneal injection (0.2 mg/kg), although less toxic by gavage. It is possible that toxins other than putative MTX-3 are produced.

Graphical abstract, Highlights • P-CTX-1B in 84 Spanish Mackerel from NSW and QLD were quantified using LC–MS/MS. • Liver & flesh from 6 fish and liver from 4 other fish were positive for P-CTX-1B. • Liver had significantly higher concentration (∼6 times) of P-CTX-1B than flesh. • No relationship was observed between length/weight of fish & detection of P-CTX-1B., Ciguatera Fish Poisoning (CFP) is a tropical disease caused by the consumption of fish contaminated with ciguatoxins (CTXs). Currently, the only feasible prevention methods for CFP are to avoid the consumption of fish of certain species from some regions, avoid larger fish of certain species, or avoid all fish caught from specific regions. Here, we quantified levels of P-CTX-1B in Spanish Mackerel (Scomberomorus commerson), which is the main fish species that causes CFP in New South Wales and Queensland, Australia, using LC–MS detection against a toxin standard. We found detectable P-CTX-1B in both flesh and liver tissues in fish from New South Wales (n = 71, 1.4% prevalence rate, with a confidence interval of 1%–4%, and 7% prevalence, 1%–12%, in flesh and liver, respectively). In the small sample of fish from Queensland, there was a 46% prevalence (19–73%, n = 13). Toxin levels found were 0.13 μg kg−1 to

© 2016 Elsevier B.V. Ciguatera fish poisoning (CFP) has been reported for many years in Rarotonga, Cook Islands, and has had the world's highest reported incidence of this illness for the last 20 years. Following intensive sampling to understand the distribution of the causative organisms of CFP, an undescribed Gambierdiscus species was isolated from the Rarotongan lagoon. Gambierdiscus cheloniae sp. nov. has the common Gambierdiscus Kofoidian plate formula (except for a variability in the number of precingular plates in aberrant cells): Po, 3′, 6″ (7″), 6C?, 6 or 7S, 5′″, 1p and 2″″. The 2′ plate is hatchet shaped and the dorsal end of 1p is pointed and the relatively narrow 1p plate. Morphologically G. cheloniae is similar to the genetically closely related species G. pacificus, G. toxicus and G. belizeanus, although smaller (depth and length) than G. toxicus. The apical pore plate varies from those of G. belizeanus and G. pacificus, which are shorter and narrower, and from G. toxicus, which is larger. G. cheloniae also differs from G. pacificus in the shape of the 2′ plate. The description of this new species is supported by phylogenetic analyses using three different gene regions. G. cheloniae produced the putative maitotoxin-3 analogue, MTX-3, but neither maitotoxin or monitored ciguatoxin. Extracts of G. cheloniae were shown to be highly toxic to mice by intraperitoneal (i.p.) injection, although they were less toxic by gavage. It is possible that this species produces toxins other than putative MTX-3.

Alexandrium catenella (formerly A. tamarense Group 1, or A. fundyense) is the leading cause of Paralytic Shellfish Poisoning in North and South America, Europe, Africa, Australia and Asia. The quantification of A.catenella via sxtA, a gene involved in Paralytic Shellfish Toxin synthesis, may be a promising approach, but has not been evaluated in situ on blooms of A. catenella, in which cell abundances may vary from not detectable to in the order of 106 cells L−1. In this study, we compared sxtA assay performance to a qPCR assay targeted to a species-specific region of ribosomal DNA (rDNA) and an established fluorescent in situ hybridization (FISH) microscopy method. Passing-Bablok regression analyses revealed the sxtA assay to overestimate abundances when A. catenella DNA were analysed, but otherwise was closer to microscopy estimates than the rDNA assay, which overestimated abundance across the full range of concentrations analysed, indicative of a copy number difference between the bloom population and a culture used for assay calibration a priori. In contrast, the sxtA assay performed more consistently, indicating less copy number variation. The sxtA assay was generally reliable, fast and effective in quantifying A. catenella and was predictive of PST contamination of shellfish.

Approximately 70 species of Prorocentrum are known, of which around 30 species are associated with benthic habitats. Some produce okadaic acid (OA), dinophysistoxin (DTX) and their derivatives, which are involved in diarrhetic shellfish poisoning. In this study, we isolated and characterized Prorocentrum concavum and P. malayense from Broome in north Western Australia using light and scanning electron microscopy as well as molecular sequences of large subunit regions of ribosomal DNA, marking the first record of these species from Australian waters. The morphology of the motile cells of P. malayense was similar to P. concavum in the light microscopy, but differed by the smooth thecal surface, the pore pattern and the production of mucous stalk-like structures and a hyaline sheath around the non-motile cells. P. malayense could also be differentiated from other closely related species, P. leve and P. foraminosum, despite the similarity in thecal surface and pore pattern, by its platelet formula and morphologies. We tested the production of OA and DTXs from both species, but found that they did not produce detectable levels of these toxins in the given culturing conditions. This study aids in establishing more effective monitoring of potential harmful algal taxa in Australian waters for aquaculture and recreational purposes.

Background: Sugira Muryango ​ (SM) is an early child development and violence-prevention home-visiting program delivered by trained lay workers. This cluster-randomised trial evaluates whether families living in extreme poverty who receive SM in combination with government-provided social protection demonstrate greater responsive and positive caregiving, nutrition, care seeking, hygiene, and father involvement compared with control families receiving usual care (UC).Methods: Sugira Muryango (SM) was delivered to families with children aged 6–36 months living in extreme poverty. We assessed changes in outcomes in intervention and UC control families using structured surveys and observation. Analyses were intent to treat using mixed models.Results: Families receiving SM improved significantly on responsive caregiving using the Home Observation for Measurement of the Environment (Cohen’s d= 0.78; p< 0.001) and the Observation of Mother-Child Interaction (Cohen’s d= 0.29; p< 0.001) and showed decreased violent discipline (OR:0.34: 95% CI: 0.22, 0.51) compared with UC. Children in families receiving SM also had a 0.44 higher increase in food groups consumed in the past 24 hours (Cohen’s d= 0.34, p< 0.001), increased care seeking for diarrhoea (OR=2.2, 95% CI: 1.5, 3.1) and fever (OR: 3.3, 95% CI: 2.3, 4.8), and improved hygiene behaviours such as proper treatment of water (OR: 3.6; 95% CI: 2.4, 5.5) compared with UC. SM was also associated with a decreased intimate partner violence (OR=0.67, 95% CI: 0.33, 1.3) and caregiver depression and anxiety (OR=0.9, 95% 0.58, 1.4).Conclusions: Sugira Muryango led to improvements in family functioning and caregiver behaviours linked to child development and health.

The marine benthic dinoflagellate genus Gambierdiscus currently contains ~ 16 species that can be highly morphologically similar to one another, and therefore molecular genetic characterization is necessary to complement the morphological species determination. Gambierdiscus species can produce ciguatoxins, which can accumulate through the food chain and cause ciguatera fish poisoning. Recent studies have suggested that Gambierdiscus excentricus may be one of the main species responsible for ciguatoxin production in the temperate and tropical regions of the eastern Atlantic. The present study definitively identifies the species, G. excentricus, from Madeira Island, Northeast-Atlantic Ocean (32° 38′ N 16° 56′ W) by examining the morphology of a strain using light and scanning electron microscopy and sequencing regions of the ribosomal DNA (D8-D10 LSU, SSU rDNA). Variability in the shape of the apical pore and the microarchitecture of the apical pore plate were documented for the first time, as well as variability in the width of the second antapical plate. The first SSU rDNA sequence for the species is reported. Because G. excentricus is known to produce high levels of CTX-like compounds, its presence and toxicity should be regularly monitored to establish whether it is the primary cause of the ciguatera poisoning events on Madeira Island.

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. In marine ecosystems, dinoflagellates can become highly abundant and even dominant at times, despite their comparatively slow growth rates. One factor that may play a role in their ecological success is the production of complex secondary metabolite compounds that can have anti-predator, allelopathic, or other toxic effects on marine organisms, and also cause seafood poisoning in humans. Our knowledge about the genes involved in toxin biosynthesis in dinoflagellates is currently limited due to the complex genomic features of these organisms. Most recently, the sequencing of dinoflagellate transcriptomes has provided us with valuable insights into the biosynthesis of polyketide and alkaloid-based toxin molecules in dinoflagellate species. This review synthesizes the recent progress that has been made in understanding the evolution, biosynthetic pathways, and gene regulation in dinoflagellates with the aid of transcriptomic and other molecular genetic tools, and provides a pathway for future studies of dinoflagellates in this exciting omics era.

From publicly available next-gen sequencing datasets of non-model organisms, such as marine protists, arise opportunities to explore their evolutionary relationships. In this study we explored the effects that dataset and model selection have on the phylogenetic inference of the Gonyaulacales, single celled marine algae of the phylum Dinoflagellata with genomes that show extensive paralogy. We developed a method for identifying and extracting single copy genes from RNA-seq libraries and compared phylogenies inferred from these single copy genes with those inferred from commonly used genetic markers and phylogenetic methods. Comparison of two datasets and three different phylogenetic models showed that exclusive use of ribosomal DNA sequences, maximum likelihood and gene concatenation showed very different results to that obtained with the multi-species coalescent. The multi-species coalescent has recently been recognized as being robust to the inclusion of paralogs, including hidden paralogs present in single copy gene sets (pseudoorthologs). Comparisons of model fit strongly favored the multi-species coalescent for these data, over a concatenated alignment (single tree) model. Our findings suggest that the multi-species coalescent (inferred either via Maximum Likelihood or Bayesian Inference) should be considered for future phylogenetic studies of organisms where accurate selection of orthologs is difficult.

Ciguatera fish poisoning is an illness contracted through the ingestion of seafood containing ciguatoxins. It is prevalent in tropical regions worldwide, including in Australia. Ciguatoxins are produced by some species of Gambierdiscus. Therefore, screening of Gambierdiscus species identification through quantitative PCR (qPCR), along with the determination of species toxicity, can be useful in monitoring potential ciguatera risk in these regions. In Australia, the identity, distribution and abundance of ciguatoxin producing Gambierdiscus spp. is largely unknown. In this study we developed a rapid qPCR assay to quantify the presence and abundance of Gambierdiscus lapillus, a likely ciguatoxic species. We assessed the specificity and efficiency of the qPCR assay. The assay was tested on 25 environmental samples from the Heron Island reef in the southern Great Barrier Reef, a ciguatera endemic region, in triplicate to determine the presence and patchiness of these species across samples from Chnoospora sp., Padina sp. and Sargassum macroalgal hosts.Author’s summaryCiguatera fish poisoning is a human disease contracted by ingesting seafood contaminated with a group of neurotoxins. The group of neurotoxins, named ciguatoxins, are synthesised by species of single celled marine algae from the genus Gambierdiscus.Ciguatera fish poisoning occurs worldwide, particularly in tropical nations. Pacific Island nations are disproportionately impacted, and this impact is predicted to increase as the effects of climate change unfold. Few effective monitoring and mitigation strategies exist for ciguatera fish poisoning, and reporting rates of the disease are estimated to be approximately 20% at best. A global ciguatera strategy was developed by a group of researchers coordinated by UNESCO’s Intergovernmental Oceanographic Commission to characterise the cause and mode of action of ciguatera fish poisoning, as a matter of urgency.In this study, we designed a qPCR assay to detect a species of microalgae, Gambierdiscus lapillus. Gambierdiscus lapillus produces compounds with ciguatoxin-like properties, which may lead to ciguatoxin uptake in fish in the Australian region. This assay was sensitive and able to detect the presence of Gambierdiscus lapillus in a range of environmental samples from the Great Barrier Reef region, Australia.

© 2018 Elsevier Ltd Harmful algal blooms are an increasing concern in the estuarine reaches of the Hawkesbury-Nepean River, one of the largest coastal rivers systems in south eastern Australia. In the austral spring of 2016, an unprecedented bloom of the harmful mixotrophic dinoflagellate Prorocentrum minimum occurred in Berowra Creek (maximum cell abundance 1.9E+06 cells L−1, 89% of the total phytoplankton community), a major tributary of this river system. In response to this bloom, our study utilises an estuary-wide, thirteen-year time series of phytoplankton abundance and environmental data to examine the spatial and temporal patterns of this harmful alga and its potential bloom drivers in this system. P. minimum cell densities and environmental parameters varied over large spatial scales, with sites located in the main channel of the estuary significantly differing from those in the more urbanized tributary of Berowra Creek. Generalised additive modelling outputs suggested that blooms of P. minimum are complex, but generally corresponded to a spatial gradient of eutrophication and salinity, whereby P. minimum growth and concomitant high chlorophyll-a concentrations were enhanced at sites that were generally less saline and more eutrophic than others. Furthermore, temporal patterns suggested that blooms occurred abruptly and lasted up to three weeks, most often during the austral autumn to spring. While significant correlations were observed between rainfall and nutrients at all other sites, suggesting a pathway for nutrient availability, the association between rainfall and nutrient delivery was generally not observed in Berowra Creek (a 15-m deep site) suggesting that a continual supply of nutrients, coupled with unique bathymetry and water residence time at this site, are the most likely contributing factors to phytoplankton growth. This study presents the most comprehensive examination of P. minimum in any southern hemisphere estuary to date and highlights the importance of continued monitoring of HABs and the important role that anthropogenic inputs have in driving blooms of P. minimum in this oyster-growing river/estuary system.

Copyright © 2018 Ajani, Kahlke, Siboni, Carney, Murray and Seymour. The ecological interactions between phytoplankton and marine bacteria have important implications for the productivity and biogeochemistry of ocean ecosystems. In this study we characterized the microbial assemblages associated with multiple isolates of the ecologically important diatom Leptocylindrus using amplicon sequencing of the 16S rRNA gene, to examine levels of conservation of the microbiome across closely related species or strains. We also assessed if the microbiome structure of a given diatom strain was dependent on the location from which it was isolated and if the microbiome of cultured isolates significantly changed overtime from the seawater in which they were isolated. The bacterial assemblages from 36 strains belonging to three species (Leptocylindrus danicus, Leptocylindrus convexus, and Leptocylindrus aporus) isolated from six locations spanning > 1000 km of south east Australian coastline over 1 year, were dominated by the Rhodobacteraceae (∼60%) and the Flavobacteriaceae (∼10%). Across all strains, only one 'core OTU' (Roseovarius sp.) was identified across all samples. We observed no significant differences in bacterial community composition between diatom species. Significant differences in microbiome structure were, however, observed between diatom strains collected at different sampling times and from differing locations, albeit these two factors were coupled. Moreover, while bacterial communities under domestication varied from the seawater in which they were isolated, they remained specific to the location/month of origin, i.e., different regions and time points harbored distinct bacterial communities. Our study delivers new knowledge in relation to diatom-bacterial associations, revealing that the location/time from which a diatom is isolated plays an important role in shaping its microbiome.

Prorocentrum minimum is a species of marine dinoflagellate that occurs worldwide and can be responsible for harmful algal blooms (HABs). Some studies have reported it to produce tetrodotoxin, however, results have been inconsistent. qPCR and molecular barcoding (amplicon sequencing) using high-throughput sequencing have been increasingly applied to quantify HAB species for ecological analyses and monitoring. Here, we isolated a strain of P. minimum from eastern Australian waters, where it commonly occurs, and developed and validated a qPCR assay for this species based on a region of ITS rRNA in relation to abundance estimates from the cultured strain as determined using light microscopy. We used this tool to quantify and examine ecological drivers of P. minimum in Botany Bay, an estuary in southeast Australia, for over ~14 months in 2016–2017. We compared abundance estimates using qPCR with those obtained using molecular barcoding based on an 18S rRNA amplicon. There was a significant correlation between the abundance estimates from amplicon sequencing and qPCR, but the estimates from light microscopy were not significantly correlated, likely due to the counting method applied. Using amplicon sequencing, ~600 unique actual sequence variants (ASVs) were found, much larger than the known phytoplankton diversity from this region. P. minimum abundance in Botany Bay was found to be significantly associated with lower salinities and higher dissolved CO2 levels.

SUMMARY The diatom Pseudo-nitzschia is a significant component of coastal waters worldwide and a producer of the potent neurotoxin, domoic acid. Sixteen species belonging to this genus have been reported from Australian waters, but the potentially toxic species P. caciantha has not been previously known from this region. Two clonal strains of P. caciantha were isolated from Coogee Beach, south-east Australia, and the morphological, molecular and toxicological evidence for this species delineation were examined using light and transmission electron microscopy, phylogenetic analysis based on sequences of the second internal transcribed spacer and domoic acid production as measured by liquid chromatography–mass spectrometry. The results unambiguously confirmed that these isolates are the potentially toxic species P. caciantha , being only the second report of this species in the Southern Hemisphere. The potential for further hidden Pseudo-nitzschia diversity in these waters is considerable.

© 2016 International Society for Microbial Ecology All rights reserved. Fatty acids, which are essential cell membrane constituents and fuel storage molecules, are thought to share a common evolutionary origin with polyketide toxins in eukaryotes. While fatty acids are primary metabolic products, polyketide toxins are secondary metabolites that are involved in ecologically relevant processes, such as chemical defence, and produce the adverse effects of harmful algal blooms. Selection pressures on such compounds may be different, resulting in differing evolutionary histories. Surprisingly, some studies of dinoflagellates have suggested that the same enzymes may catalyse these processes. Here we show the presence and evolutionary distinctiveness of genes encoding six key enzymes essential for fatty acid production in 13 eukaryotic lineages for which no previous sequence data were available (alveolates: dinoflagellates, Vitrella, Chromera; stramenopiles: bolidophytes, chrysophytes, pelagophytes, raphidophytes, dictyochophytes, pinguiophytes, xanthophytes; Rhizaria: chlorarachniophytes, haplosporida; euglenids) and 8 other lineages (apicomplexans, bacillariophytes, synurophytes, cryptophytes, haptophytes, chlorophyceans, prasinophytes, trebouxiophytes). The phylogeny of fatty acid synthase genes reflects the evolutionary history of the organism, indicating selection to maintain conserved functionality. In contrast, polyketide synthase gene families are highly expanded in dinoflagellates and haptophytes, suggesting relaxed constraints in their evolutionary history, while completely absent from some protist lineages. This demonstrates a vast potential for the production of bioactive polyketide compounds in some lineages of microbial eukaryotes, indicating that the evolution of these compounds may have played an important role in their ecological success.

A group of marine dinoflagellates (Alveolata, Eukaryota), consisting of similar to 10 species of the genus Alexandrium, Gymnodinium catenatum and Pyrodinium bahamense, produce the toxin saxitoxin and its analogues (STX), which can accumulate in shellfish, leading to ecosystem and human health impacts. The genes, sxt, putatively involved in STX biosynthesis, have recently been identified, however, the evolution of these genes within dinoflagellates is not clear. There are two reasons for this: uncertainty over the phylogeny of dinoflagellates; and that the sxt genes of many species of Alexandrium and other dinoflagellate genera are not known. Here, we determined the phylogeny of STX-producing and other dinoflagellates based on a concatenated eight-gene alignment. We determined the presence, diversity and phylogeny of sxtA, domains A1 and A4 and sxtG in 52 strains of Alexandrium, and a further 43 species of dinoflagellates and thirteen other alveolates. We confirmed the presence and high sequence conservation of sxtA, domain A4, in 40 strains (35 Alexandrium, 1 Pyrodinium, 4 Gymnodinium) of 8 species of STX-producing dinoflagellates, and absence from non-producing species. We found three paralogs of sxtA, domain A1, and a widespread distribution of sxtA1 in non-STX producing dinoflagellates, indicating duplication events in the evolution of this gene. One paralog, clade 2, of sxtA1 may be particularly related to STX biosynthesis. Similarly, sxtG appears to be generally restricted to STX-producing species, while three amidinotransferase gene paralogs were found in dinoflagellates. We investigated the role of positive (diversifying) selection following duplication in sxtA1 and sxtG, and found negative selection in clades of sxtG and sxtA1, clade 2, suggesting they were functionally constrained. Significant episodic diversifying selection was found in some strains in clade 3 of sxtA1, a clade that may not be involved in STX biosynthesis, indicating pressure for diversification of function. (C) 2015 Elsevier Inc. All rights reserved.

© 2020 Elsevier Ltd In March 2018, an unprecedented bloom of a species of Pseudo-nitzschia occurred in Berowra Creek, a major tributary of the Hawkesbury River estuary, New South Wales, Australia (max cell abundance 5.7 × 106 cells L−1). Morphological and phylogenetic analysis showed the bloom was dominated by the species P. delicatissima, with toxin characterization by LC-MS confirming one of the seven strains isolated produced domoic acid (DA), at a concentration of 0.34 pg DA per cell. In response to this unprecedented bloom, we used a fifteen year series of phytoplankton and physico-chemical data to relate environmental factors to spatial and temporal variability of Pseudo-nitzschia species throughout the estuary. Species in the Pseudo-nitzschia delicatissima group consistently dominated all locations monitored throughout the estuary, with peak cell densities observed in the austral autumn (lowest in winter). Overall, Generalised Additive Models (GAMs) suggested that high cell concentrations of Pseudo-nitzschia were linked to an increase in soluble reactive phosphorus and a decrease in total nitrogen at all sites, with up to 55% of the deviance explained. Twenty species of Pseudo-nitzschia have now been reported in Australian coastal waters, four of which are confirmed DA producers. We hypothesise that increased urbanization, nutrient input and warmer waters could combine to increase Pseudo-nitzschia blooms in south-eastern Australia.

In marine ecosystems, dinoflagellates can become highly abundant and even dominant at times, despite their comparatively slow growth. Their ecological success may be related to their production of complex toxic polyketide compounds. Ostreopsis species produce potent palytoxin-like compounds (PLTX), which are associated with human skin and eye irritations, and illnesses through the consumption of contaminated seafood. To investigate the genetic basis of PLTX-like compounds, we sequenced and annotated transcriptomes from two PLTX-producing Ostreopsis species; O. cf. ovata, O. cf. siamensis, one non-PLTX producing species, O. rhodesae and compared them to a close phylogenetic relative and non-PLTX producer, Coolia malayensis. We found no clear differences in the presence or diversity of ketosynthase and ketoreductase transcripts between PLTX producing and non-producing Ostreopsis and Coolia species, as both groups contained >90 and > 10 phylogenetically diverse ketosynthase and ketoreductase transcripts, respectively. We report for the first-time type I single-, multi-domain polyketide synthases (PKSs) and hybrid non-ribosomal peptide synthase/PKS transcripts from all species. The long multi-modular PKSs were insufficient by themselves to synthesize the large complex polyether backbone of PLTX-like compounds. This implies that numerous PKS domains, including both single and multi-, work together on the biosynthesis of PLTX-like and other related polyketide compounds.

© 2018 by the authors. Ciguatera Fish Poisoning (CFP) is a human illness caused by the consumption of marine fish contaminated with ciguatoxins (CTX) and possibly maitotoxins (MTX), produced by species from the benthic dinoflagellate genus Gambierdiscus. Here, we describe the identity and toxicology of Gambierdiscus spp. isolated from the tropical and temperate waters of eastern Australia. Based on newly cultured strains, we found that four Gambierdiscus species were present at the tropical location, including G. carpenteri, G. lapillus and two others which were not genetically identical to other currently described species within the genus, and may represent new species. Only G. carpenteri was identified from the temperate location. Using LC-MS/MS analysis we did not find any characterized microalgal CTXs (P-CTX-3B, P-CTX-3C, P-CTX-4A and P-CTX-4B) or MTX-1; however, putative maitotoxin-3 (MTX-3) was detected in all species except for the temperate population of G. carpenteri. Using the Ca2+ influx SH-SY5Y cell Fluorescent Imaging Plate Reader (FLIPR) bioassay we found CTX-like activity in extracts of the unidentified Gambierdiscus strains and trace level activity in strains of G. lapillus. While no detectable CTX-like activity was observed in tropical or temperate strains of G. carpenteri, all species showed strong maitotoxin-like activity. This study, which represents the most comprehensive analyses of the toxicology of Gambierdiscus strains isolated from Australia to date, suggests that CFP in this region may be caused by currently undescribed ciguatoxins and maitotoxins.

© 2014 Elsevier GmbH. The Alexandrium tamarense species complex is one of the most studied marine dinoflagellate groups due to its ecological, toxicological and economic importance. Several members of this complex produce saxitoxin and its congeners - potent neurotoxins that cause paralytic shellfish poisoning. Isolates from this complex are assigned to A. tamarense, A. fundyense, or A. catenella based on two main morphological characters: the ability to form chains and the presence/absence of a ventral pore between Plates 1' and 4'. However, studies have shown that these characters are not consistent and/or distinctive. Further, phylogenies based on multiple regions in the rDNA operon indicate that the sequences from morphologically indistinguishable isolates partition into five clades. These clades were initially named based on their presumed geographic distribution, but recently were renamed as Groups I-V following the discovery of sympatry among some groups. In this study we present data on morphology, ITS/5.8S genetic distances, ITS2 compensatory base changes, mating incompatibilities, toxicity, the sxtA toxin synthesis gene, and rDNA phylogenies. All results were consistent with each group representing a distinct cryptic species. Accordingly, the groups were assigned species names as follows: Group I, A. fundyense; Group II, A. mediterraneum; Group III, A. tamarense; Group IV, A. pacificum; Group V, A. australiense.

© 2017 by the authors. Licensee MDPI, Basel, Switzerland. Between 2014 and 2016, five cases of ciguatera fish poisoning (CFP), involving twenty four individuals, were linked to Spanish Mackerel (Scomberomorus commerson) caught in the coastal waters of the state of New South Wales (NSW) on the east coast of Australia. Previously, documented cases of CFP in NSW were few, and primarily linked to fish imported from other regions. Since 2015, thirteen individuals were affected across four additional CFP cases in NSW, linked to fish imported from tropical locations. The apparent increase in CFP in NSW from locally sourced catch, combined with the risk of CFP from imported fish, has highlighted several considerations that should be incorporated into risk management strategies to minimize CFP exposure for seafood consumers.

© 2017 The Royal Society of New Zealand. In this study, we assessed the use of DNA metabarcoding as a method for biodiversity assessment of benthic-epiphytic dinoflagellate communities and for detecting rare, toxin-producing taxa. Mock communities and three primer pairs were used to establish the recovery of species signal and quantitative representation of species in the samples, as well as to determine primer biases, bioinformatic filtering steps, and threshold levels. Samples were analysed using high-throughput sequencing Illumina™ MiSeq technology. We did not find a relationship between read number and cell abundance for all treatments. However, the method was extremely sensitive, with two of the primer pairs detecting a single cell representing less than 0.001% of the cells in the sample. Benthic and epiphytic dinoflagellate communities were also collected from the Bay of Islands (Northland, New Zealand). Dinophyceae species richness was much higher when samples were analysed using metabarcoding than when analysed by microscopy, and we detected several new taxonomic records for New Zealand.

© 2017 The Authors Journal of Phycology published by Wiley Periodicals, Inc. on behalf of Phycological Society of America Dinoflagellates are prolific producers of polyketide compounds, many of which are potent toxins with adverse impacts on human and marine animal health. To identify polyketide synthase (PKS) genes in the brevetoxin-producing dinoflagellate, Karenia brevis, we assembled a transcriptome from 595 million Illumina reads, sampled under different growth conditions. The assembly included 125,687 transcripts greater than 300 nt in length, with over half having >100× coverage. We found 121 transcripts encoding Type I ketosynthase (KS) domains, of which 99 encoded single KS domains, while 22 contained multiple KS domains arranged in 1–3 protein modules. Phylogenetic analysis placed all single domain and a majority of multidomain KSs within a monophyletic clade of protist PKSs. In contrast with the highly amplified single-domain KSs, only eight single-domain ketoreductase transcripts were found in the assembly, suggesting that they are more evolutionarily conserved. The multidomain PKSs were dominated by trans-acyltransferase architectures, which were recently shown to be prevalent in other algal protists. Karenia brevis also expressed several hybrid nonribosomal peptide synthetase (NRPS)/PKS sequences, including a burA-like sequence previously reported in a wide variety of dinoflagellates. This contrasts with a similarly deep transcriptome of Gambierdiscus polynesiensis, which lacked NRPS/PKS other than the burA-like transcript, and may reflect the presence of amide-containing polyketides in K. brevis and their absence from G. polynesiensis. In concert with other recent transcriptome analyses, this study provides evidence for both single domain and multidomain PKSs in the synthesis of polyketide compounds in dinoflagellates.

Creative Commons This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0 Metadata associated with this Data Descriptor is available at http://www.nature.com/sdata/ and is released under the CC0 waiver to maximize reuse., There have been many individual phytoplankton datasets collected across Australia since the mid 1900s, but most are unavailable to the research community. We have searched archives, contacted researchers, and scanned the primary and grey literature to collate 3,621,847 records of marine phytoplankton species from Australian waters from 1844 to the present. Many of these are small datasets collected for local questions, but combined they provide over 170 years of data on phytoplankton communities in Australian waters. Units and taxonomy have been standardised, obviously erroneous data removed, and all metadata included. We have lodged this dataset with the Australian Ocean Data Network (http://portal.aodn.org.au/) allowing public access. The Australian Phytoplankton Database will be invaluable for global change studies, as it allows analysis of ecological indicators of climate change and eutrophication (e.g., changes in distribution; diatom:dinoflagellate ratios). In addition, the standardised conversion of abundance records to biomass provides modellers with quantifiable data to initialise and validate ecosystem models of lower marine trophic levels.

© 2017 by the authors; licensee MDPI, Basel, Switzerland. Phycotoxins, which are produced by harmful microalgae and bioaccumulate in the marine food web, are of growing concern for Australia. These harmful algae pose a threat to ecosystem and human health, as well as constraining the progress of aquaculture, one of the fastest growing food sectors in the world. With better monitoring, advanced analytical skills and an increase in microalgal expertise, many phycotoxins have been identified in Australian coastal waters in recent years. The most concerning of these toxins are ciguatoxin, paralytic shellfish toxins, okadaic acid and domoic acid, with palytoxin and karlotoxin increasing in significance. The potential for tetrodotoxin, maitotoxin and palytoxin to contaminate seafood is also of concern, warranting future investigation. The largest and most significant toxic bloom in Tasmania in 2012 resulted in an estimated total economic loss of ∼AUD$23M, indicating that there is an imperative to improve toxin and organism detection methods, clarify the toxin profiles of species of phytoplankton and carry out both intra- and inter-species toxicity comparisons. Future work also includes the application of rapid, real-time molecular assays for the detection of harmful species and toxin genes. This information, in conjunction with a better understanding of the life histories and ecology of harmful bloom species, may lead to more appropriate management of environmental, health and economic resources.