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Between 1898 and 1940, eight human cases of diphyllobothriasis were reported in Argentina, always in recently arrived European immigrants. In 1982, the first autochthonous case was detected, and since then, 33 other autochthonous cases have been reported, totaling 42 cases of human diphyllobothriasis in Argentina before the present study. Our aim is to update the information on diphyllobothriasis in Argentina by identifying specimens from new cases using morphometrical and/or molecular methods. We also aim to assess the epidemiological relevance of this food-borne disease in the country. Anamnestic data were obtained from patients or professionals, along with 26 worms identified using morphometrical (21 samples) and molecular techniques (5 samples). All the patients acquired the infection by consuming freshwater salmonids caught in Andean lakes in Northern Patagonia. Morphometrics and DNA markers of worms were compatible with Dibothriocephalus latus. In total, 68 human cases have been detected in Argentina, 60 of which were autochthonous. The human population living North-western Patagonia, whose lakes are inhabited by salmonids, is increasing. Similarly, the number of other definitive hosts for Dibothriocephalus dendriticus (gulls) and for D. latus (dogs) is also increasing. In addition, salmonid fishing and the habit of consuming home-prepared raw fish dishes are becoming widespread. Therefore, it is to be expected that diphyllobothriasis in Argentina will increase further.

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Background: Knowledge of the physical and environmental conditions that may limit the migration of invasive species is crucial to assess the potential for expansion outside their native ranges. The cactus moth, Cactoblastis cactorum, is native to South America (Argentina, Paraguay, Uruguay and Brazil) and has been introduced and invaded the Caribbean and southern United States, among other regions. In North America there is an ongoing process of range expansion threatening cacti biodiversity of the genus Opuntia and the commercial profits of domesticated Opuntia ficus-indica. Methods: To further understand what influences the distribution and genetic structure of this otherwise important threat to native and managed ecosystems, in the present study we combined ecological niche modeling and population genetic analyses to identify potential environmental barriers in the native region of Argentina. Samples were collected on the host with the wider distribution range, O. ficus-indica. Results: Significant genetic structure was detected using 10 nuclear microsatellites and 24 sampling sites. At least six genetic groups delimited by mountain ranges, salt flats and wetlands were mainly located to the west of the Dry Chaco ecoregion. Niche modeling supports that this region has high environmental suitability where the upper soil temperature and humidity, soil carbon content and precipitation were the main environmental factors that explain the presence of the moth. Environmental filters such as the upper soil layer may be critical for pupal survival and consequently for the establishment of populations in new habitats, whereas the presence of available hosts is a necessary conditions for insect survival, upper soil and climatic characteristics will determine the opportunities for a successful establishment.

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The Southeast Asian-native Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), also known as "spotted-wing Drosophila," is one of the most globally invasive agricultural species. Although D. suzukii is a pest spread throughout all the Argentinian fruit-growing regions, few information has been published on its impact on local fruit production. Parasitoid species associated with D. suzukii in Argentina belong to Pteromalidae (Chalcidoidea), Diapriidae (Diaprioidea), both attacking host pupae, and Figitidae (Cynipoidea), which attack host larvae. Nine Eucoilinae (Figitidae) species, belonging to Dicerataspis, Dieucoila, Euxestophaga, Ganaspis, Hexacola, and Leptopilina genera, have been associated with D. suzukii in Argentina. Ceratitis capitata (Wiedemann), commonly known as "medfly," is native to Africa and has a worldwide distribution, covering many tropical, subtropical, and temperate regions. In Argentina, C. capitata has been associated with several native hymenopterous parasitoids belonging to Braconidae (Ichneumonioidea), Eulophidae (Chalcidoidea), Pteromalidae, Diapriidae, and Figitidae families. Only two eucoline species, Ganaspis pelleranoi (Brèthes) and Leptopilina haywardi (Blanchard) have been related to medfly in Argentina. We report new trophic associations between the parasitoids Dicerataspis grenadensis Ashmead and Leptopilina boulardi (Barbotin, Carton and Kelner-Pillault) and D. suzukii, and between the parasitoid Odontosema albinerve Kieffer and C. capitata, after surveys conducted in Tucumán, northwestern Argentina. An annotated checklist and a taxonomic key of Eucoilinae associated with both invasive pests, in Argentina, are also provided.

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The growth of international trade, coupled with an expansion of large-scale pine plantations in South America during the second half of the twentieth century, has significantly increased the opportunities for the invasion of forest insects. Bark beetles (Coleoptera: Curculionidae, Scolytinae) are a large and diverse group of insects, commonly recognized as one of the most important tree mortality agents in coniferous forests worldwide and an important group among invasive forest species. In this study, we combined data from field sampling with published records of established non-native pine bark beetles, to describe their distribution and invasion history in pine plantations across southern South America, reviewing the available information on their phenology and host range. We obtained records of established populations of six Eurasian species distributed in two major regions: the southwest region comprises plantations in Chile and the Argentine Patagonia, with four bark beetle species: Hylastes ater, Hylastes linearis, Hylurgus ligniperda, and Orthotomicus laricis; the northeastern zone includes northeastern Argentina, Uruguay, and southern Brazil, and includes three bark beetle species: Cyrtogenius luteus, H. ligniperda, and O. erosus. The establishment of non-native populations across the study area began in the 1950s, and from the 1980s onwards, there has been an exponential increase in introductions. We predict that several of these species will continue spreading across South America and that new species will continue arriving. We highlight the importance of international collaboration for early detection and management of non-native pine bark beetles.

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The historical and geographical properties of the archipelagos allow a detailed study of species diversification, and phenotypic traits can indicate the extent of such processes. Eupelmus pulchriceps (Cameron, 1904) is an exotic species to the Galapagos archipelago, and generalist parasitoid that attacks a beetle species that consumes the seeds of the invasive shrub Leucaena leucocephala (Lam.) de Wit. Despite extensive sampling, the wasp is recorded only in Santa Cruz and San Cristobal islands of the Galapagos archipelago. Thus, using 112 female wasps, we compare body size, proportion, and allometric differentiations within and between the two islands. There were no body size differences between islands. A PerMANOVA indicates differences between the islands and a single differentiation between two localities of one island. Allometric differences between islands were not the same for all structures. These results are consistent with the greater distance between islands than between localities and suggest a differentiation process. The variables with allometric differentiation are associated with wings and ovipositor, possibly responding to different ecological pressures. It is interesting that this parasitoid, recently arrived at the archipelago, is already showing differentiation. Also, it is essential to monitor the behavior of these wasps in the archipelago, given their potential to access other species affecting the trophic interactions of the local biota.

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Abstract Biological invasions are one of the major threats to biodiversity and good quality of life, resulting from the translocation of species by human action. There are more than 500 alien species currently invading ecosystems in Brazil, particularly plants and fishes, while little is known about invasive microorganisms. Although invasive alien species are present in all ecosystems in the country, most have been recorded in habitats with greater human interference, such as urban and peri-urban areas, farmland, dams, reservoirs, ports, and canals. Historically, the southern and southeastern regions of Brazil have had more invasive alien species, but there has been an increase in the number of invasive alien species in the central-western and northern regions in recent decades. The ornamental trade of plants and fishes as well as the illegal pet trade of wild mammals and reptiles are some of the main pathways for invasive species introduction and spread in Brazil. Breeding and cultivation systems that allow escape to natural areas are a relevant route of species introductions in freshwater ecosystems, while unintentional introductions from shipping and infrastructure are of extreme concern in marine ecosystems. The negative impacts of invasive alien species on the biota mainly include changes in community structure and local decrease in native species richness, mediated by predation, competition, and ecosystem changes. Most negative impacts are recorded for intentionally introduced species, such as fishes and plants, but unintentional introductions have led to impacts on good quality of life, with associated costs and impacts on human health. The management of biological invasions faces challenges that need to be overcome, such as the lack of public knowledge about the impact of invasive alien species, the popular appeal of charismatic invasive species or those used by humans, and the use of controversial control techniques. However, successful experiences of eradication and control in terrestrial and marine ecosystems have been recorded, some of them involving public engagement in management actions. Recognizing the issue as a cross-cutting public policy and developing ongoing governance experiences are fundamental goals for the management of invasive alien species in Brazil.

Resumo Invasões biológicas são uma das maiores ameaças à biodiversidade e à boa qualidade de vida, ocorrendo a partir da translocação de espécies por ação humana. Existem mais de 500 espécies exóticas invadindo ecossistemas atualmente no Brasil, com destaque para plantas e peixes. Pouco se sabe sobre microrganismos invasores. Apesar de existirem espécies exóticas invasoras em todos os ecossistemas no país, a maior parte dos registros foi feita em hábitats com maior interferência humana, como áreas urbanas, periurbanas, terras cultivadas, represas, reservatórios, portos e canais. Historicamente, as regiões sul e sudeste do Brasil apresentam mais espécies exóticas invasoras, mas nas últimas décadas se tem observado um aumento no número de espécies exóticas invasoras nas regiões centro-oeste e norte. O comércio de plantas e peixes ornamentais, assim como o comércio ilegal de mamíferos e répteis silvestres como animais de estimação são algumas das principais vias de introdução e disseminação de espécies exóticas invasoras no Brasil. Sistemas de criação e cultivo que possibilitam o escape para áreas naturais são uma relevante via de introdução em ecossistemas de águas continentais, enquanto introduções não intencionais a partir de navegação e de infraestrutura são de extrema preocupação em ecossistemas marinhos. Os impactos negativos de espécies exóticas invasoras sobre a biota incluem principalmente alterações na estrutura de comunidades e diminuição local da riqueza de espécies nativas, mediados por predação, competição e modificações ecossistêmicas. A maior parte dos impactos negativos registrados ocorreram para espécies introduzidas intencionalmente, como peixes e plantas, mas introduções não intencionais têm levado a impactos na boa qualidade de vida, com custos associados e impactos sobre a saúde humana. A gestão de invasões biológicas esbarra em desafios a serem superados, tais como a falta de conhecimento do público sobre o impacto de espécies exóticas invasoras, o apelo popular de espécies invasoras carismáticas ou utilizadas por humanos e o emprego de técnicas controversas de controle. Entretanto, experiências bem-sucedidas de erradicação e controle em ecossistemas terrestres e marinhos têm sido registrados, alguns deles envolvendo engajamento público nas ações de manejo. Reconhecer o tema como uma política pública transversal e desenvolver experiências continuadas de governança são metas fundamentais para a gestão e o manejo de espécies exóticas invasoras no Brasil.

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Drosophila suzukii (Matsumura 1931) is a cosmopolitan horticultural pest originally from temperate East Asia; yet, its recent introduction in southeast and central Brazil raises the possibility it might expand into warmer climatic zones. In theoretical terms, the adaptive potential of invasive species can be impaired by the lack of genetic variation, but, on the other hand, phenotypic plasticity might play an important role in the adaptation to the new environment. In this context, we investigated the effects of temperature variation (18°C, 22°C, and 28°C) on fitness traits and size of male reproductive organs (accessory glands and testis) in a natural D. suzukii population recently introduced in the neotropical region. Development time decreased significantly with increasing temperature, but egg-to-adult survival was not affected, attaining rates around 50% for the three temperatures. Development at 28°C affected differentially adult male and female biological performance: males displayed higher mortality and severe and permanent reduction in offspring production, whereas females showed the same mortality as controls and a temporary decrease in offspring production, followed of a clear recovery. Finally, reproductive organs size in immature and mature males was affected by developmental temperature variation in the following ways. Testis length decreased with body size (i.e., at higher temperatures) and increased with maturation time after adult hatching, whereas for accessory glands there was no significant difference between different temperatures, resulting in proportionally larger glands for smaller body sizes. These results show differences in developmental dynamics of reproductive tract structures due to temperature variation.

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The lionfish is an exotic invasive fish native to the Indo-Pacific, which is established in the western Atlantic Ocean and the Caribbean Sea. Lionfish can affect native fishes and invertebrates through direct predation or competition for food. The present review aims to analyze the most relevant characteristics of the biology and ecology of lionfish as an invasive alien species, with an emphasis on Cuba. We provide a current view of the well-known lionfish as a successful invasive fish, and we put in this context the information regarding lionfish in Cuban waters, enriching the background knowledge, and giving novel and relevant information. The compilation of numerous publications on the subject has allowed for a more complete analysis of essential aspects of this invader in the Cuban archipelago. The consulted literature records that the first report of lionfish in Cuba occurred in 2007; subsequently, sightings of lionfish were reported in numerous localities. In 2010, the lionfish was considered an invasive alien species, which currently is established in various habitats, at depths up to 188 m, throughout the Cuban archipelago (e.g., coral reefs, mangroves, seagrass beds, submerged artificial structures). In addition, it has reached very high densities (12.42 ind./100 m2), which exceed those reported in the Indo-Pacific as well as in many locations in the Western Atlantic. It has been confirmed that the lionfish in Cuba also presents numerous characteristics that guarantee its success as an invader, among them: less quantity and diversity of parasites than other Atlantic fishes found in similar environments, a high number of gametes in the gonads, reproductive activity during all year and wide diet. The most important fish families for the lionfish diet in Cuba have been Pomacentridae, Gobiidae, Scaridae, Holocentridae, Mullidae, Labridae and Acanthuridae; and the most important crustacean orders are Decapoda, Mysida, Stomatopoda and Isopoda. In Cuba, as in the entire invaded region, numerous investigations have been directed to evaluate the impact of this invader on ecosystems, and although there is enough information, their results differ. Additional studies are required to assess the impact of lionfish as a predator after several years of invasion on a larger geographic scale in Cuba and other areas of the region. This knowledge will allow the development of more effective control strategies. Periodic lionfish culling have been carried out in Cuban MPAs as a control strategy, and some positive results have been observed, such as the average size reduction; however, further efforts are still required. Due to the importance of the study of lionfish as an invader, this review is a necessity as it provides, for the first time, a comprehensive analysis of lionfish information and results from Cuba, which is adequately contrasted with previous studies of other areas, particularly, from the Greater Caribbean.

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To gain insights into the trichurid diversity in pre-Hispanic remains of South American camelids (SACs), as well as into modern SAC populations, a bibliographic search was carried out to find parasitological studies. Results showed that a total of 17 studies were performed at archaeological and paleontological sites, in which a total of 213 samples were examined. The sample set was used as the unit of analysis, and 83% of 52 pre-Hispanic sample sets were positive for parasites. Parasitological studies confirmed the pre-Hispanic presence of diverse trichurids: two Trichuris species and capillariid eggs with morphological differences that allowed them to be assigned to three different species. Currently, the richness of the native trichurid assemblages in SACs has been extended by the inclusion of two species (Trichuris sp. 2 and Capillariinae gen. sp. 1). Modern T. tenuis Chandler, 1930, considered SAC-specific, would have invaded SAC populations during the European colonization. The estimate of regional and temporal trichurid prevalence and paleoecological information allowed us to propose a possible origin for some of them. Although the present analysis is exploratory, it should stimulate future studies about the biogeographic history of SAC helminths, provide relevant information to improve descriptions of the Holocene ecology, and identify threatened helminths.

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Poeciliids are widely recognized as successful invaders, possessing traits associated with invasion success. Native to Central America and south-eastern Mexico, the twospot livebearer (Pseudoxiphophorus bimaculatus) is a species recently recognized as invasive in both Central and northern Mexico. Despite its invasive status, limited research exists on its invasion process and the potential threats it poses to native species. In this study, we conducted a comprehensive review of the current knowledge on the twospot livebearer and mapped its current and potential distribution worldwide. The twospot livebearer shares similar traits with other successful invaders within the same family. Notably, it exhibits high fecundity throughout the year and demonstrates resilience to highly polluted and oxygen-deprived water conditions. This fish serves as a host for several parasites, including generalists, and has been extensively translocated for commercial purposes. Recently, it has also been used for biocontrol within its native range. Apart from existing outside its native range, the twospot livebearer, under current climate conditions and if transported there, could readily colonize biodiversity hotspots in tropical zones worldwide, including the Caribbean Islands, the Horn of Africa, North of Madagascar Island, south-eastern Brazil, and others located in southern and eastern Asia. Given that this fish is highly plastic and our Species Distribution Model, we consider that all areas with a habitat suitability >0.2 should prevent its arrival and establishment. Our findings underscore the urgent need to recognize this species as a threat to freshwater native topminnows and prevent its introduction and spread.

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Although biological invasions are a common and intensively studied phenomenon, most studies often ignore the biotic interactions that invasive species play in the environment. Here, we evaluated how and why invasive plant species are interconnected within the overall frugivory network of the Brazilian Atlantic Forest, an important global biodiversity hotspot. To do this, we used the recently published Atlantic Frugivory Dataset to build a meta-network (i.e., a general network made of several local networks) that included interactions between 703 native and invasive plant species and 331 frugivore species. Using tools derived from complex network theory and a bootstrap simulation approach, we found that the general structure of the Atlantic Forest frugivory network (i.e., nestedness and modularity) is robust against the entry of invasive plant species. However, we observed that invasive plant species are highly integrated within the frugivory networks, since both native and invasive plant species play similar structural roles (i.e., plant status is not strong enough to explain the interactive roles of plant species). Moreover, we found that plants with smaller fruits and with greater lipid content play a greater interactive role, regardless of their native or invasive status. Our findings highlight the biotic homogenization involving plant-frugivore interactions in the Atlantic Forest and that the impacts and consequences of invasive plant species on native fauna can be anticipated based on the characteristics of their fruits.

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Identifying the areas of the world with suitable environmental conditions for the establishment of invasive species represents a fundamental basis for preventing their impacts. One of the most widely used tools for this is ecological niche modeling. Nonetheless, this approach may underestimate the specie's physiological tolerances (it's potential niche) since wildlife populations of species usually do not occupy their entire environmental tolerance. Recently, it has been suggested that incorporating occurrences of phylogenetically related species improves the prediction of biological invasions. However, the reproducibility of this technique remains unclear. Here, we evaluated the generality of this protocol by assessing whether the construction of modeling units above species level improves the capacity of niche models to predict the distribution of 26 target marine invasive species. For each, we constructed supraspecific modeling units based on published phylogenies by grouping the native occurrence records of each invasive species with the records of its phylogenetically closest relative. We also considered units at species level, including only the presence of records in the native areas of the target species. We generated ecological niche models for each unit with three modeling methods (minimum volume ellipsoids - MVE, machine learning algorithms - Maxent and a presence-absence method - GLM). In addition, we grouped the 26 target species based on whether or not the species are in environmental pseudo-equilibrium (i.e., it occupies all habitats where it can disperse) and have any geographical or biological constraints. Our results suggest that the construction of supraspecific units improves the predictive capacity of correlative models to estimate the invasion area of our target species. This modeling approach consistently generated models with a higher predictive ability for species in non-environmental pseudo-equilibrium and with geographical constraints.

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Exotic species are one of the main threats to biodiversity, leading to alterations in the structure and functioning of natural ecosystems. However, they can sometimes also provide ecological services, such as seed dispersal. Therefore, we assessed the ecological impacts of exotic species on native dispersal systems and the mechanisms underlying the disruption of mutualistic plant-disperser interactions. Exotic species negatively affect dispersal mutualisms by (i) altering dispersal behavior and visitation rates of native dispersers, (ii) predating native dispersers, (iii) transmitting forest pathogens, and (iv) predating seeds. Conversely, positive impacts include the dispersal of native plants, forest regeneration, and native habitat restoration via (i) increasing the visitation rates of frugivorous birds, (ii) facilitating the colonization and establishment of native forest trees, (iii) enhancing forest species seedling survival, and (iv) facilitating seed rain and seedling recruitment of early and late successional native plants. The reviewed studies provide similar results in some cases and opposite results in others, even within the same taxa. In almost all cases, exotic species cause negative impacts, although sometimes they are necessary to ensure native species' persistence. Therefore, exotic species management requires a comprehensive understanding of their ecological roles, since the resulting effects rely on the complexity of native-exotic species interactions.

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Invasive alien species are considered one of the main threats to marine biodiversity. We used a BACI design to investigate the changes in rocky reef benthic communities related to the invasion of the octocoral Latissimia ningalooensis in the Southwest Atlantic. Drastic changes in benthic community structure were restricted to the invaded site and associated with the growth of L. ningalooensis on turf algae. Conversely, the zoanthid Palythoa caribaeorum remained stable coverage along the 9-year study period, indicating a greater biotic resistance against the octocoral. Latissimia ningalooensis spread from large and well-established patches to new areas of the reef, increasing turf-octocoral interactions. This study warns of the great invasive potential of the octocoral, due to its high abundance, competitive and expansion ability. The decline in abundance of turf-forming algae following the emergence of L. ningalooensis threatens the structure and functioning of macroalgal-dominated rocky reefs.

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Citizen science is a valuable tool for early detection, distribution, and spread of invasive alien species (IAS). Nevertheless, citizen science initiatives have several potential biases and may be complemented with long-term structured monitoring schemes. We analyzed the spatial-temporal dynamics of the invasion of Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Chile, based upon two citizen sciences databases (WEB and INAT) and one structured monitoring (SAG). We collected 8638 H. axyridis occurrences between 2009 and 2020. WEB had a higher number of records than SAG and INAT, and in all databases, the number of records has increased over time. The three databases showed that the invasion started in central Chile and then spread toward the north and south. The WEB and SAG recorded occurrences in the extreme north and south, whereas INAT concentrated all the occurrences in a more limited area, included in WEB and SAG. Both citizen science initiatives concentrated their records in areas of high human populations whereas SAG records had a more even distribution across regions. At 2020, WEB accounted for 55%, SAG 54%, and INAT 8% of the total area accumulated with H. axyridis, with only 16% of area shared among databases. WEB and INAT obtained most of their records in urban and industrial land cover types, while SAG records were more evenly represented in different land cover types. Our results confirm that combined methods, including citizen science initiatives, national surveillance system, and localized samplings, complement each other in providing knowledge to understand the patterns, processes, and consequences of this invasion.

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Abstract This is the 1st record of the Sonneratia apetala Buch.-Ham., in the mangroves of South America - Cubatão-Baixada Santista, State of São Paulo, Brazil. The record was made in an area located 2 km apart from the port of Santos. Its arrival was probably made through the ballast water. S. apetala as well an exotic it is also an aggressive mangrove species. All 85 individuals identified were georeferenced. In May 2023 they were flowering and in August they already had ripe fruits/propagules. The presence of exotic species in mangroves is worrying, they can cause profound ecological and economic impacts and negatively influence the restoration of native ecosystems. The presence of S. apetala in the mangroves of Cubatão region could bring about a radical change in the biological structure of the mangrove ecosystem, in addition to being a new point of dispersal to others areas.

Resumo Este é o primeiro registro da ocorrência de Sonneratia apetala Buch.-Ham., na América do Sul, Cubatão-Baixada Santista, Estado de São Paulo, Brasil. O registro ocorreu em área situada a 2 km do porto de Santos. Sua presença, se fez, provavelmente, por meio da água de lastro dos navios. A S. apetala é uma espécie exótica agressiva nos manguezais dessa região. Todos os 85 exemplares identificados foram georeferenciados. Em maio de 2023 estavam floridas e em agosto já tinha frutos/propágulos maduros. A presença de espécies exóticas nos manguezais é preocupante, pois são capazes de gerar impactos ecológicos e econômicos e influenciar, negativamente, na restauração desse ecossistema no estuário de Cubatão. A presença da S.apetala, no manguezal da região de Cubatão pode povocar uma mudança radical na estrutura biológica do ecossistema manguezal, além de ser um novo ponto de dispersão para outras áreas.

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Alien plant species are colonizing high-elevation areas along roadsides. In this study, we evaluated whether the distributions of alien plants in the central Chilean mountains have reached climatic equilibrium (i.e., upper distribution limits consistent with their climatic requirements). First, we evaluated whether the upper elevational limits of alien plants changed between 2008 and 2018 based on the Mountain Invasion Research Network (MIREN) database. Second, we compared the observed upper elevational limits with the upper limits predicted by each species' global climatic niche. On average across species, the upper elevation limit did not change between 2008 and 2018. However, most species maintained the same limit or shifted downward, while only 23% of the species shifted upwards. This lack of change does not mean that the species' distributions are in equilibrium with the climate, because the observed upper limit was lower than the limit predicted by the global niche model for 87% of species. Our results suggest that alien species in this study region may not only be climate-limited, but could also be limited by other local-scale factors, such as seed dispersal, intermittent disturbance rates, soil type and biotic interactions.

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The Hindustan citrus mite, Schizotetranychus hindustanicus (Acari: Tetranychidae), is an invasive pest in South America and constitutes a threat to Brazilian citriculture. This study aimed to determine the contribution of weather variables to the seasonal abundance of S. hindustanicus and the best sampling scheme (sampling variable and unit) for this mite. Populations of S. hindustanicus were monitored monthly in an orange orchard for 31 months in Roraima state, Brazil. Eggs, mobile stages, and the symptoms caused by S. hindustanicus were sampled in different combinations of canopy quadrants, vertical tree strata, and branch sections. The optimal sampling variable and sampling unit for S. hindustanicus scouting were determined according to fidelity and precision criteria. Rainfall and high air temperature were the main factors reducing S. hindustanicus populations. The most suitable variable for S. hindustanicus sampling was egg count. The optimal sampling unit was a leaf collected in the central section of branches located in the middle tree stratum. In addition, the sample should be taken from the southwest quadrant. Collectively, this study adds to the understanding of S. hindustanicus population dynamics and provides a sampling scheme for better management of this pest.

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To understand the factors that limit invasive expansion in alien species, it is critical to predict potential zones of colonization. Climatic niche can be an important way to predict the potential distribution of alien species. This correlation between niche and geographic distribution is called Hutchinson's duality. A combination of global and regional niches allows four invasive stages to be identified: quasi-equilibrium, local adaptation, colonization and sink stage. We studied the invasive stages of six alien leguminous species either in the niche or the geographical space. In five of the six species, a higher proportion of populations were in the quasi-equilibrium stage. Notably, Acacia species had the highest proportion of populations in local adaptation. This picture changed dramatically when we projected the climatic niche in the geographic space: in all species the colonization stage had the highest proportional projected area, ranging from 50 to 90%. Our results are consistent with Hutchinson's duality, which predicts that small areas in the niche space can be translated onto large areas of the geographic space. Although the colonization stage accounted for a low proportion of occurrences, in all species, the models predicted the largest areas for this stage. This study complements invasive stages, projecting them in geographic space.

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The azooxanthellate corals Tubastraea coccinea and T. tagusensis invaded the Brazilian coast in the 1980s and is still in expansion, favored by lower predation and competition pressure in their new habitats. Interestingly, the native sponge Desmapsamma anchorata has been observed overgrowing these corals. Considering that competitive displacement is expected to play a major role in the successful outcome of an invasion, the present study tested the physical and chemical mechanisms possibly involved in the competition between D. anchorata and the Tubastraea corals through field and aquaria experiments as well as the Raman spectroscopy technique for chemical analysis. Our results showed that the sponge grew in all directions including over Tubastraea colonies and regardless of its presence. There was no evidence of a specific chemical response among sponges or corals. However, we observed the extrusion of mesenteric filaments and tentacles of corals and the projection of sponge tissue during interspecific interaction, which suggests that physical imposition plays a key role for space competition at micro scales. Given the interspersed nature of benthic species distributions and the fast expansion of Tubastraea, it is unlikely that D. anchorata or any other sponges could serve a biological control against these invasive corals at larger scales, but our results showed that at a microscale they can withstand the corals presence and even outgrow them locally.

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