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Interactions between bacterial microbiota and epibenthic species of the dinoflagellate Prorocentrum may define the onset and persistence of benthic harmful algal blooms (bHABs). Chemical ecological interactions within the dinoflagellate phycosphere potentially involve a complex variety of organic molecules, metabolites, and toxins, including undefined bioactive compounds. In this study, the bacterial diversity and core members of the dinoflagellate-associated microbiota were defined from 11 strains of three epibenthic Prorocentrum species, representing three geographically disjunct locations within Mexican coastal waters. Microbiota profiles in stable monoclonal Prorocentrum cultures were obtained by sequencing amplicons of the V3-V4 region of the 16S rRNA gene. Thirteen classes of bacteria were identified among dinoflagellate clones, where Alphaproteobacteria, Gammaproteobacteria, and Bacteroidia were consistently dominant. The bacterial community structure exhibited significantly different grouping by the location of origin of dinoflagellate clones. No significant diversity difference was found among free-living or unattached bacteria in the dinoflagellate culture medium (M) compared with those in closer association with the dinoflagellate host cells (H). Twelve taxa were defined as core members of the bacterial assemblage, representing the genera Algiphilus, Cohaesibacter, Labrenzia, Mameliella, Marinobacter, Marivita, Massilia, Muricauda, Roseitalea, and an unclassified member of the Rhodobacteraceae. The core members are inferred to significantly contribute to primary and secondary metabolic functions, but no direct correlation with dinoflagellate toxigenicity was apparent. Overall the bacterial profile and implied gene functionality indicated a suite of positive interactions, suggesting either mutualism or commensalism with the dinoflagellate. The further characterization and interpretation of specific gene functions and interactions between bacteria and dinoflagellates, such as epibenthic members of genus Prorocentrum, are key to understanding their role in toxigenesis and bHAB development.

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Monitoring is essential to ensure that environmental goals are being achieved, including those of sustainable agriculture. Growing interest in environmental monitoring provides an opportunity to improve monitoring practices. Approaches that directly monitor land cover change and biodiversity annually by coupling the wall-to-wall coverage from remote sensing and the site-specific community composition from environmental DNA (eDNA) can provide timely, relevant results for parties interested in the success of sustainable agricultural practices. To ensure that the measured impacts are due to the environmental projects and not exogenous factors, sites where projects have been implemented should be benchmarked against counterfactuals (no project) and control (natural habitat) sites. Results can then be used to calculate diverse sets of indicators customized to monitor different projects. Here, we report on our experience developing and applying one such approach to assess the impact of shaded cocoa projects implemented by the Instituto de Manejo e Certificação Florestal e Agrícola (IMAFLORA) near São Félix do Xingu, in Pará, Brazil. We used the Continuous Degradation Detection (CODED) and LandTrendr algorithms to create a remote sensing-based assessment of forest disturbance and regeneration, estimate carbon sequestration, and changes in essential habitats. We coupled these remote sensing methods with eDNA analyses using arthropod-targeted primers by collecting soil samples from intervention and counterfactual pasture field sites and a control secondary forest. We used a custom set of indicators from the pilot application of a coupled monitoring framework called TerraBio. Our results suggest that, due to IMAFLORA's shaded cocoa projects, over 400 acres were restored in the intervention area and the community composition of arthropods in shaded cocoa is closer to second-growth forests than that of pastures. In reviewing the coupled approach, we found multiple aspects worked well, and we conclude by presenting multiple lessons learned.

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The high numbers of COVID-19 cases and deaths in Brazil have made Latin America an epicentre of the pandemic. SARS-CoV-2 established sustained transmission in Brazil early in the pandemic, but important gaps remain in our understanding of virus transmission dynamics at a national scale. We use 17,135 near-complete genomes sampled from 27 Brazilian states and bordering country Paraguay. From March to November 2020, we detected co-circulation of multiple viral lineages that were linked to multiple importations (predominantly from Europe). After November 2020, we detected large, local transmission clusters within the country. In the absence of effective restriction measures, the epidemic progressed, and in January 2021 there was emergence and onward spread, both within and abroad, of variants of concern and variants under monitoring, including Gamma (P.1) and Zeta (P.2). We also characterized a genomic overview of the epidemic in Paraguay and detected evidence of importation of SARS-CoV-2 ancestor lineages and variants of concern from Brazil. Our findings show that genomic surveillance in Brazil enabled assessment of the real-time spread of emerging SARS-CoV-2 variants.

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Bacterial diversity was explored among field samples and cultured isolates from coral reefs within the Veracruz Reef System. Bacterioplankton and bacteriobenthos were characterized by pyrosequencing 16S rRNA genes. Identified sequences belonged to the kingdom Bacteria and classified into 33 phyla. Proteobacteria (likely SAR11 clade) dominated in collective field samples, whereas Firmicutes were the most abundant taxa among cultured isolates. Bioinformatic sorting of sequences to family level revealed 223 bacterial families. Pseudomonadaceae, Exiguobacteraceae and Bacillaceae were dominant among cultured isolates. Vibrionaceae, Alteromonadaceae, and Flavobacteriaceae dominated in reef-associated sediments, whereas Rickettsiaceae and Synechoccaceae were more highly represented in the water column. Bacterial communities from sediments were more diverse than from the water column. This study reveals cryptic bacterial diversity among microenvironmental components of marine microbial reef communities subject to differential influence of anthropogenic stressors. Such investigations are critical for constructing scenarios of environmentally induced shifts in bacterial biodiversity and species composition.

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BACKGROUND: Basic sanitation could be a potential indicator of the spread of coronavirus disease-2019 (COVID-19) and, in this context, space-time patterns are important tools with which to elucidate the spread of disease and identify risk factors. The aim of this study was to assess a possible association between basic sanitation indices and COVID-19 rates in all the 5570 municipalities of Brazil and its spatial distribution. METHODS: Data of COVID-19 cases registered in Brazil from 28 February until 31 May 2020 and independent variables associated with basic sanitation were included. RESULTS: High incidence rates were significantly associated with precarious water service index (0-25% coverage) and offstandard faecal coliforms index for tap water (5-50% and 75-100% of samples tested). A significant association between high mortality rates and sewage collection (0-25% coverage)/treatment (25-50% coverage) indices was also verified. In addition, clusters with significant spatial autocorrelation were identified mainly in the North and Northeast regions for mortality and incidence rates (high-high risk areas) and for offstandard faecal coliforms index. Those regions are considered the poorest in Brazil, presenting with low incomes, human agglomerations, as well as a poor basic sanitation system, which also hinder the implementation of COVID-19-preventative measures. CONCLUSIONS: A precarious basic sanitation infrastructure could potentially be associated with the high transmission of severe acute respiratory syndrome coronavirus-2 in Brazil.

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BACKGROUND: Despite visceral leishmaniasis (VL) being epidemic in most Brazilian regions, the Northeast region is responsible for the highest morbidity and mortality outcomes within the country. OBJECTIVE: To analyse the spatiotemporal dynamics of VL cases to identify the temporal trends and high-risk areas for VL transmission, as well as the association of the disease with social vulnerability in Brazilian Northeast. METHODS: We carried out an ecological time series study employing spatial analysis techniques using all VL confirmed cases of 1,794 municipalities of Brazilian Northeast between the years 2000 to 2017. The Social Vulnerability Index (SVI) was used to represent the social vulnerability. Incidence rates were standardized and smoothed by the Local Empirical Bayesian Method. Time trends were examined through segmented linear regression. Spatiotemporal analysis consisted of uni- and bivariate Global and Local Moran indexes and space-time scan statistics. RESULTS: Incidence rate remained stable and ranged from 4.84 to 3.52 cases/100,000 inhabitants. There was higher case prevalence between males (62.71%), children and adolescents (63.27%), non-white (69.75%) and urban residents (62.58%). Increasing trends of new cases were observed among adult male subjects (≥ 40 years old) and urban residents. Importantly, VL incidence showed a direct spatial dependence. Spatial and space-time clusters were identified in sertão and meio-norte sub-regions, overlapping with high social vulnerability areas. CONCLUSIONS: VL is a persistent health issue in Brazilian Northeast and associated with social vulnerability. Space-time clustering of VL cases in socially vulnerable municipalities demands intersectoral public policies of surveillance and control, with focus on reducing inequalities and improving living conditions for regional inhabitants.

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The biodiverse Neotropical ecoregion remains insufficiently assessed, poorly managed, and threatened by unregulated human activities. Novel, rapid and cost-effective DNA-based approaches are valuable to improve understanding of the biological communities and for biomonitoring in remote areas. Here, we evaluate the potential of environmental DNA (eDNA) metabarcoding for assessing the structure and distribution of fish communities by analysing water and sediment from 11 locations along the Jequitinhonha River catchment (Brazil). Each site was sampled twice, before and after a major rain event in a five-week period and fish diversity was estimated using high-throughput sequencing of 12S rRNA amplicons. In total, 252 Molecular Operational Taxonomic Units (MOTUs) and 34 fish species were recovered, including endemic, introduced, and previously unrecorded species for this basin. Spatio-temporal variation of eDNA from fish assemblages was observed and species richness was nearly twice as high before the major rain event compared to afterwards. Yet, peaks of diversity were primarily associated with only four of the locations. No correlation between ß-diversity and longitudinal distance or presence of dams was detected, but low species richness observed at sites located near dams might that these anthropogenic barriers may have an impact on local fish diversity. Unexpectedly high α-diversity levels recorded at the river mouth suggest that these sections should be further evaluated as putative "eDNA reservoirs" for rapid monitoring. By uncovering spatio-temporal changes, unrecorded biodiversity components, and putative anthropogenic impacts on fish assemblages, we further strengthen the potential of eDNA metabarcoding as a biomonitoring tool, especially in regions often neglected or difficult to access.

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BACKGROUND: Leptospirosis is an endemic disease in Brazil of social and economic relevance related to behavioural and socioenvironmental factors. This study aimed to analyse the spatiotemporal distribution of the incidence of leptospirosis and its association with social determinants in health in a state of northeastern Brazil. METHODS: An ecological study of temporal series with techniques of spatial analysis using secondary data of the cases of leptospirosis notified in the Information System of Notifiable Diseases of the state of Sergipe (2008-2017) was conducted. The analysis of temporal trends was performed using Poisson regression. Spatial analyses were performed using the Moran index, the local empirical Bayesian model, scan statistics and spatial regression. RESULTS: The incidence rate decreased from 3.66 to 1.44 cases per 100 000 inhabitants in 2008 and 2017, respectively. Leptospirosis was associated with social inequities, mostly affecting males aged 20-49 y living in urban areas. The space-time scan indicated the formation of a risk cluster in municipalities in the metropolitan region of the state. CONCLUSIONS: The data indicated the persistence of leptospirosis transmission, maintaining a pattern of high endemicity in some municipalities associated with social inequities. The study showed the temporal and spatial dynamics of the disease to better target specific actions for prevention and control.

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STUDY DESIGN: An analysis of employment status data up to 10 years following the Federal Drug Administration (FDA) Investigational Device Exemption (IDE) randomized trial and extension as post-approval study comparing BRYAN cervical disc (Medtronic, Minneapolis, MN) arthroplasty (CDA) versus single-level anterior cervical discectomy and fusion (ACDF) was performed. OBJECTIVE: Ten-year experience with the BRYAN disc arthroplasty trial provides opportunity to report patient employment data. SUMMARY OF BACKGROUND DATA: The long-term consequences of arthroplasty remain incomplete, including the occurrence of occupational compromise. METHODS: Patients' employment status were measured at regular intervals in both groups up to 10 years. RESULTS: The preoperative employment status proportion was comparable between investigational (BRYAN CDA) and control (ACDF) groups. In the investigational group, 49.2% returned to work at 6 weeks compared with 39.4% of the control group (P = 0.046). At 6 months and 2 years postoperatively, there was a similar likelihood of active employment in both groups. After 2 years at all time points, 10% drop-off seen in control group employment, but not in investigational group. At 10 years, 76.2% CDA patients were employed to 64.1% ACDF patients (P = 0.057). Preoperative variables influencing work status at 10 years following CDA included: preoperative work status, age, and SF-36 Mental Component Score (SF-36 MCS); whereas, no significant preoperative factor identified with ACDF. Time to return to work was influenced in both groups by preoperative work status; and in the ACDF group: reaching age 65 at 10-year visit, preoperative arm pain and NDI score had significant influences. CONCLUSION: More patients returned to work at 6 weeks after CDA compared with ACDF, although there was no difference by 6 months. After 2 years, a nonsignificant trend toward higher employment rates in the arthroplasty group was evident, but this difference could not be validated due to the very high rate of loss of patients to the follow-up. LEVEL OF EVIDENCE: 2.

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Most species of Amazonian snakes have wide geographic distributions. However, local environmental factors influence the formation of assemblages in different localities. In this study, we investigated the composition of the assemblage and the effect of environmental variables on the distribution of the species inhabiting an upland forest in the Experimental Farm area of the Federal University of Amazonas in Manaus, Brazil. Data collection was carried out in 24 standardized plots. Each plot was sampled four times between July 2015 and April 2017 by active search method. We recorded 83 individuals from 29 species belonging to six families. The richness in the study area corresponded to 78% of the snake species and 100% of the families previously recorded for Manaus. As observed in other localities, the most abundant species was the Amazonian lancehead (Bothrops atrox). Multiple linear regression models did not detect any effect of environmental variables on species richness and abundance of individuals. However, quadratic polynomial regression models revealed that intermediate canopy opening percentages positively influence the richness and abundance of snakes. It is possible that the result is related to a tradeoff between the thermoregulation behavior of these animals and to their susceptibility to predation.

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The process of population aging is a worldwide reality becoming a global public health challenge. Although population aging is especially noticeable in more developed regions, there has also been a significant advance in the quantity of elderly people in areas with unfavourable socioeconomic indicators, and a rapid growth in countries with a low level of economic development. This article presents an analysis based on spatial autocorrelation of the relationship between life expectancy and social determinants in a north-eastern region of Brazil. An ecological study was conducted using the secondary data of social, demographic, and health indicators of elderly people collected in the Brazilian Demographic Census of the 75 municipalities of the state of Sergipe. Spatial autocorrelation was evaluated using the Moran global index and the local indicators of space association. Multiple linear regression models were used to identify the relationship between life expectancy and social determinants. The South-eastern region of the state presented clusters with all indicators pointing to acceptable lifestyles, whereas the municipalities of the north-western and far-eastern regions were characterized by values demonstrating precarious living conditions. The high dependency ratio, illiteracy rate, and unemployment rate among elderly people had a negative impact on life expectancy. The evidence confirms that there is an autocorrelation between social determinants and life expectancy, indicating that the worse the social, economic, and health indicators are, the lower the life expectancy. This finding indicates the need to redirect public policies and formulate strategies aimed at reducing social and health inequalities.

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This is an ecological study with exploratory analysis of spatial and temporal data based on mortality data with respect to prostate cancer obtained from the Mortality Information System concerning residents of the state of Sergipe, Brazil between 2000 and 2015. The analysis of temporal trends was performed using the Joinpoint Regression Program through Poisson regression. Spatial analysis was performed using the empirical Bayesian model, Kernel analysis, Global Moran and Local indices. There were 1,986 deaths due to prostate cancer, most of which occurring after 60 years of age. An increasing, non-constant but significant trend in mortality rates was noted. The kernel density estimator showed hotspot densities of the highest rates of prostate cancer mortality in the north-eastern and central regions of the state. High-risk clusters were identified for prostate cancer mortality (I = 0.55, P<0.01). There was an increase in prostate cancer mortality rates and a heterogeneous geographic distribution of risk areas, with high-risk priority areas identified in certain regions of the state. These priority areas include the municipalities located in the Northeast (Amparo do São Francisco, Aquidabã, Canhoba, Cedro de São João and Telha), the West (Frei Paulo and Pedra Mole) and the south-western region of the state (Poço Verde and Simão Dias).

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Due to contact and misuse of water drainage channels, schistosomiasis has spread and become a constant concern in northeastern Brazil. The aim of this study was to monitor human cases of Schistosomiasis mansoni and the breeding areas of the snail intermediate host Biomphalaria glabrata through spatial analysis in a community named Invasão do Canal do Guaxinim, located in Barra dos Coqueiros City in an endemic coastal part of the state of Sergipe, Brazil. This research was performed as a cross-sectional epidemiological study conducted with parasitological and malacological surveys. To verify the spatial analysis, a two-year spatial point pattern analysis was performed by means of Kernel intensity estimation using TerraView software 4.2.2. A schistosomiasis prevalence reduction from 8.1% (2013) to 4.9% (2014) was observed but mild infection prevailed in adolescents and/or young adults during the two-year study. In malacological research, 387 specimens of snails of the genus B. glabrata were collected and all were negative with regard to schistosomiasis. Spatial analysis showed a strong, spatial trend of increased transmission risk areas north and south of the community, both in 2013 and 2014. In Invasão do Canal do Guaxinim itself, the increased risk was only seen in the northern part. When combined, the human and the malacological spatial analyses constituted an important methodological approach for monitoring and controlling this parasitic disease.

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Guanidinium toxins, such as saxitoxin (STX), tetrodotoxin (TTX) and their analogs, are naturally occurring alkaloids with divergent evolutionary origins and biogeographical distribution, but which share the common chemical feature of guanidinium moieties. These guanidinium groups confer high biological activity with high affinity and ion flux blockage capacity for voltage-gated sodium channels (NaV). Members of the STX group, known collectively as paralytic shellfish toxins (PSTs), are produced among three genera of marine dinoflagellates and about a dozen genera of primarily freshwater or brackish water cyanobacteria. In contrast, toxins of the TTX group occur mainly in macrozoa, particularly among puffer fish, several species of marine invertebrates and a few terrestrial amphibians. In the case of TTX and analogs, most evidence suggests that symbiotic bacteria are the origin of the toxins, although endogenous biosynthesis independent from bacteria has not been excluded. The evolutionary origin of the biosynthetic genes for STX and analogs in dinoflagellates and cyanobacteria remains elusive. These highly potent molecules have been the subject of intensive research since the latter half of the past century; first to study the mode of action of their toxigenicity, and later as tools to characterize the role and structure of NaV channels, and finally as therapeutics. Their pharmacological activities have provided encouragement for their use as therapeutants for ion channel-related pathologies, such as pain control. The functional role in aquatic and terrestrial ecosystems for both groups of toxins is unproven, although plausible mechanisms of ion channel regulation and chemical defense are often invoked. Molecular approaches and the development of improved detection methods will yield deeper understanding of their physiological and ecological roles. This knowledge will facilitate their further biotechnological exploitation and point the way towards development of pharmaceuticals and therapeutic applications.

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Monte Carlo simulations were performed in the isothermal-isobaric ensemble (NPT) to calculate the Henry constants of methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) in pure H2O, amines, and alkanolamines using the classical Lorentz-Berthelot combining rules (L-B). The Henry constants of N2O and CO2 in water are highly overestimated and motivated us to propose a new set of unlike interactions. Contrarily, the Henry constant of N2O in MEA is underestimated by around 40%, and again, a new reoptimized cross unlike parameter is able to reproduce the constant to within 10%. An analysis is given of the relationship between the physical absorption of these gases and the chemical structure or functionality of 12 molecules including amines and alkanolamines using the anisotropic united atom intermolecular potential (AUA4). Finally, the solubility of N2O in an aqueous solution of monoethanolamine (MEA) at 30% (wt) was also studied. A Henry constant within 7% of the experimental value was found by using the reoptimized parameters along with L-B to account for the MEA + H2O unlike interactions. This very good agreement without additional adjustments for the MEA + H2O system may be attributed to the good excess properties predictions found in previous works for the binary mixture (MEA + H2O). However, further work, including additional alkanolamines in aqueous solutions at several concentrations, is required to verify this particular point.

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Saxitoxin (STX) and its analogs are paralytic alkaloid neurotoxins that block the voltage-gated sodium channel pore (Nav), impeding passage of Na⁺ ions into the intracellular space, and thereby preventing the action potential in the peripheral nervous system and skeletal muscle. The marine dinoflagellate Gymnodinium catenatum produces an array of such toxins, including the recently discovered benzoyl analogs, for which the mammalian toxicities are essentially unknown. We subjected STX and its analogs to a theoretical docking simulation based upon two alternative tri-dimensional models of the Nav1.4 to find a relationship between the binding properties and the known mammalian toxicity of selected STX analogs. We inferred hypothetical toxicities for the benzoyl analogs from the modeled values. We demonstrate that these toxins exhibit different binding modes with similar free binding energies and that these alternative binding modes are equally probable. We propose that the principal binding that governs ligand recognition is mediated by electrostatic interactions. Our simulation constitutes the first in silico modeling study on benzoyl-type paralytic toxins and provides an approach towards a better understanding of the mode of action of STX and its analogs.

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Biological control on crop infesting insects represent an useful method in modern agriculture. A search for parasitoids of the macadamia nutborer was carried out during a three year study, and their effect on the population fluctuation of the borer was determined. An egg parasitoid belonging to the family Trichogrammatidae and four larval parasitoids, Microgastrine I, Microgastrine II, Ascogaster sp. (Hymeoptera: Braconidae) and Pristomerus sp. (Hymeoptera: Ichneumonidae) were recovered. Parasitism percentage by Microgastrine I was 15% in 1991, 16% in 1992 and 4% in 1993; Microgastrine II was not collected in 1991, but accounted for a 4.3% of parasitism in 1992 and 3.7% in 1993; Ascogaster sp. was registered since 1992 with 3% parasitism (29% in 1993). We found an inverse relationship between total parasitism and the mean of damaged nuts. Parasitoids play an important role in the reduction of the G. aurantianum population. Rev. Biol. Trop. 57 (4): 1245-1252. Epub 2009 December 01.

Durante tres años se realizó una búsqueda de los enemigos naturales del barrenador de la nuez de macadamia y se determinó el efecto sobre su población. Se registró un parasitoide de huevo perteneciente a la familia Trichogrammatidae y cuatro parasitoides de larva, Microgastrine I, Microgastrine II, y Ascogaster sp. (Hym: Braconidae) y Pristomerus (Hym: Ichneumonidae). El porcentaje de parasitismo por Microgastrine I fue del 15% en 1991, 16% en 1992 y 4% en 1993; Microgastrine II no se registró en 1991, pero alcanzó un 4.3% de parasitismo en 1992 y un 3.7% en 1993; Ascogaster sp. se registró a partir de 1992 con un 3% de parasitismo y con un 29% en 1993. Se encontró una relación inversa entre el parasitismo total y el promedio de nueces dañadas. Los resultados indican que los parasitoides juegan un papel importante en la disminución de la población de G. aurantianum.

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Biological control on crop infesting insects represent an useful method in modem agriculture. A search for parasitoids of the macadamia nutborer was carried out during a three year study, and their effect on the population fluctuation of the borer was determined. An egg parasitoid belonging to the family Trichogrammatidae and four larval parasitoids, Microgastrine I, Microgastrine II, Ascogaster sp. (Hymeoptera: Braconidae) and Pristomerus sp. (Hymeoptera: Ichneumonidae) were recovered. Parasitism percentage by Microgastrine I was 15% in 1991, 16% in 1992 and 4% in 1993; Microgastrine II was not collected in 1991, but accounted for a 4.3% of parasitism in 1992 and 3.7% in 1993; Ascogaster sp. was registered since 1992 with 3% parasitism (29% in 1993). We found an inverse relationship between total parasitism and the mean of damaged nuts. Parasitoids play an important role in the reduction of the G. aurantianum population.

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People all over the world use their hands to communicate expressively. Autonomous gestures, also known as emblems, are highly social in nature, and convey conventionalized meaning without accompanying speech. To study the neural bases of cross-cultural social communication, we used single pulse transcranial magnetic stimulation (TMS) to measure corticospinal excitability (CSE) during observation of culture-specific emblems. Foreign Nicaraguan and familiar American emblems as well as meaningless control gestures were performed by both a Euro-American and a Nicaraguan actor. Euro-American participants demonstrated higher CSE during observation of the American compared to the Nicaraguan actor. This motor resonance phenomenon may reflect ethnic and cultural ingroup familiarity effects. However, participants also demonstrated a nearly significant (p = 0.053) actor by emblem interaction whereby both Nicaraguan and American emblems performed by the American actor elicited similar CSE, whereas Nicaraguan emblems performed by the Nicaraguan actor yielded higher CSE than American emblems. The latter result cannot be interpreted simply as an effect of ethnic ingroup familiarity. Thus, a likely explanation of these findings is that motor resonance is modulated by interacting biological and cultural factors.

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Giant Amazon river turtles, Podocnemis expansa, are indigenous to the Amazon, Orinoco, and Essequibo River basins, and are distributed across nearly the entire width of the South American continent. Although once common, their large size, high fecundity, and gregarious nesting, made P. expansa especially vulnerable to over-harvesting for eggs and meat. Populations have been severely reduced or extirpated in many areas throughout its range, and the species is now regulated under Appendix II of the Convention on International Trade in Endangered Species. Here, we analyse data from mitochondrial DNA sequence and multiple nuclear microsatellite markers with an array of complementary analytical methods. Results show that concordance from multiple data sets and analyses can provide a strong signal of population genetic structure that can be used to guide management. The general lack of phylogeographic structure but large differences in allele and haplotype frequencies among river basins is consistent with fragmented populations and female natal-river homing. Overall, the DNA data show that P. expansa populations lack a long history of genetic differentiation, but that each major tributary currently forms a semi-isolated reproductive population and should be managed accordingly.

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