Southern Limit Of Distribution Research Articles

The role of temperature in shaping Culex acharistus mosquitoes life history traits in its southern limit of distribution (Patagonia-Argentina)

There is substantial evidence showing that temperature have a great impact on insects behavior, phenology and life histories. Because of mosquito global importance as disease vectors, in temperate regions where climatic conditions could be only borderline suitable for mosquito development, there is a growing interest in understanding the effect of temperature shifts on vital statistics to more accurately define how such changes could impact distribution and abundance patterns, as well as disease transmission cycles. We determined the role of ambient temperature under fluctuating conditions in shaping Culex acharistus (Diptera: Culicidae) life history traits, and estimated its development threshold and physiological time, in its southern limit of distribution in the Argentine Patagonia region. Four horizontal life tables were conducted under natural fluctuating temperature range in Esquel city (42°S – 71°W; 563 m a.s.l.), during spring-summer (17°C), summer (15.4°C), summer-autumn (12.7°C) and autumn-winter (5.6°C) seasons. Larvae, pupae and adult traits were recorded. The mean duration of the experiments varied between 28 to ≅100 days for spring-summer and autumn-winter seasons. Only during the cold season experiment pupae experienced the most severe temperatures and freeze-thaw cycles, and failed to reach adult stage. We found that larva and pupa development time, adult emergence time and longevity significantly increased with decreasing temperatures, while larval survival was greatest at an intermediate temperature and decreased toward low and high values. Also, protandry was observed and males emerge 2 days before females across seasons. Temperature development threshold and physiological time estimated for larva + pupa were 5.98°C and 211.24°C-days. Our study contributes to a growing body of knowledge by examining the effect of seasonal changes in temperature on mosquito life history traits. Results obtained here can be applied as useful parameters in the development of population dynamic models, improving current mosquito control strategies in cold-temperate regions.

The Soil Seed Bank Role in Mountainous Heathland Ecosystems after Fire and Inorganic Nitrogen Fertilization

Calluna vulgaris-dominated heathlands are a priority habitat type in Annex I of the Habitats Directive (92/43/ECC, habitat code 4060). In the Iberian Peninsula, the landscape of the Cantabrian Mountain range has great heterogeneity due to human management during the last 10,000 years. Another factor that can affect these communities is the increase in human-induced atmospheric nitrogen (N) deposition. During the last century, there has been a dramatic increase in N deposition rates. For all these reasons, it is important to know the regeneration dynamics of the heathlands in the context of the disturbances that these communities currently face (i.e., N deposition, fire, and decrease in sheep grazing) in the Cantabrian Mountain range. In this study, we characterized the plant species composition and soil seed bank after prescribed burning in three heathlands on their southern distribution limit in Spain, to gain insights into regenerative capacity and conservation of these communities. The results obtained suggest that the post-burn soil seed bank could restore Calluna-dominated vegetation in these habitats, indicating that the restoration potential from the soil seed bank after wildfires of these habitats is high. Our results also suggest that, in the short term after burning, the main characteristic species such as Calluna and Erica are recovered, which is fundamental to maintain the heathland community structure.

The Saccharina latissima microbiome: Effects of region, season, and physiology.

Saccharina latissima is a canopy-forming species of brown algae and, as such, is considered an ecosystem engineer. Several populations of this alga are exploited worldwide, and a decrease in the abundance of S. latissima at its southern distributional range limits has been observed. Despite its economic and ecological interest, only a few data are available on the composition of microbiota associated with S. latissima and its role in algal physiologyn. We studied the whole bacterial community composition associated with S. latissima samples from three locations (Brittany, Helgoland, and Skagerrak) by 16S metabarcoding analyses at different scales: algal blade part, regions, season (at one site), and algal physiologic state. We have shown that the difference in bacterial composition is driven by factors of decreasing importance: (i) the algal tissues (apex/meristem), (ii) the geographical area, (iii) the seasons (at the Roscoff site), and (iv) the algal host's condition (healthy vs. symptoms). Overall, Alphaproteobacteria, Gammaproteobacteria, and Bacteroidia dominated the general bacterial communities. Almost all individuals hosted bacteria of the genus Granulosicoccus, accounting for 12% of the total sequences, and eight additional core genera were identified. Our results also highlight a microbial signature characteristic for algae in poor health independent of the disease symptoms. Thus, our study provides a comprehensive overview of the S. latissima microbiome, forming a basis for understanding holobiont functioning.

On the taxonomy and diversity of Cruciferae in Kazakhstan

Taxonomy and species diversity of the mustard family (Cruciferae or Brassicaceae) in Kazakhstan is updated. Draba bajtenovii described and hitherto known from Kungei Alatau is synonymized with D. fladnizensis for which it is a southern limit of distribution in the Eurasia, while Trans-Ili Alatau endemic D. microcarpella is found conspecific with a montane Asian D. lanceolata. Noccaea thlaspidioides (N. cochleariformis) is confirmed to occur in the country based on collections from Altai. Finally, Isatis trachycarpa and Smelowskia annua are shown to be absent in the flora of Kazakhstan due to the lack of gatherings confirming their occurrence in the country.

A tool for a race against time: Dispersal simulations to support ongoing monitoring program of the invasive coral Tubastraea coccinea

Preventing, detecting, and monitoring invasive marine species is a big challenge as it is not possible to visualize all invasion extensions. Their early detection may be the best chance to achieve eradication. The Indo-pacific scleractinian coral Tubastraea coccinea invasion in the Atlantic dates from the late 1930s. Since then, disruptive populations were found along ~8.000 km of west Atlantic, and in the Canarian Islands of Spain (east Atlantic), related to vessel fouling in the oil and gas industry. Their impacts have been noticed from endemic species to ecosystems. In Brazil, initiatives to control Tubastraea spp. have been done mostly by local environmental managers and researchers, but recently a National Plan for Prevention, Control and Monitoring (NPPCM) for Tubastraea spp. was approved. We applied an Individual-based Model within the invasion history of Tubastraea coccinea in its southern distribution limit in the Atlantic, on the rocky shore of the Arvoredo Biological Marine Reserve. We indicated hotspots for the occurrence of possible emerging invasion sites in the region and expect to support ongoing monitoring programs in defining priority areas for their early detection. The model is easily replicated and might be a valuable tool for decision makers.

Flowering effort and reproductive phenology of intertidal colonizing Zostera marina

The seagrass Zostera marina can inhabit the intertidal where the variable environmental conditions mean that the seagrass meadows are frequently in a continuous state of colonization, influencing, among others, their phenology and flowering effort. This could be especially notable in the southern limits of the species' distribution, where light exposure and temperature reach extreme values during the warmer seasons. In this study, we evaluate the flowering effort, phenology, photophysiology and vegetative development of recent colonizing Z. marina patches inhabiting the intertidal of a lagoon located near its southern limit of distribution, in the Ria de Aveiro (Portugal). To evaluate the effects of low tide exposure, tidepool and emerged seagrass patches were selected. Results showed short-lived differences in the phenology of the flowering of the patches and in their vegetative development, but in general, the photosynthetic activity, timing of flowering, densities of spathes and flowering shoots were similar in emerged and tidepool patches throughout the entire reproductive period (from June to August). The spathes per flowering shoot and the spathe and flowering shoot densities per unit of area of the colonizing patches were comparable to that obtained in other perennial intertidal meadows of this species and its timing was adjusted to that which occurred in areas of similar latitudes, ending when the temperature exceeded 25 °C. These results imply that intertidal colonizing Z. marina patches can flowering similarly to perennial meadows, regardless of whether or not they are submerged in pools at low tide, which implies a great adaptability of the species to intertidal areas. However, to fully understand the reproductive capacity of Z. marina in the Ria de Aveiro, future studies should determine the capacity of these flowers to form mature seeds, as well as their ability to germinate naturally in the area.

Sharing the Space: Variation in Morphometric, Ecoregional, Migratory and Reproductive Patterns of Three Sympatric Artibeus Species

Bats of the phyllostomid genus Artibeus are primarily frugivorous, and they often are captured carrying the fruits of figs (Ficus spp.) or Cecropia spp. Although two or three species of Artibeus (sensu stricto) are found sympatrically in many regions of the Neotropics, little is known about the potential competitive interactions of these congeners in areas of sympatry. Competition might occur for food, roost sites, or other resources, and might be expressed as spatial or temporal partitioning in feeding or reproduction, as increased displacement of feeding- or foraging-related characters, or as some combination of these factors. These effects might be more pronounced near the distributional limits of the species, where resources might be more limited (both in abundance and diversity), and more patchily distributed. Three species of Artibeus (A. fimbriatus, A. lituratus, and A. planirostris), are at or near their southern or south-western distributional limits in Paraguay. Previous analyses in Paraguay have determined that A. lituratus and A. planirostris are migratory, with A. lituratus being most abundant during the wet season (October–February), and A. planirostris in the variable season (March–May). Artibeus fimbriatus and A. lituratus are relatively more abundant in the Atlantic Forest ecoregion; and A. planirostris in the Cerrado. In this study we examined morphometric variation in wing and craniomandibular characters, as well as reproductive patterns, to further explore the potential niche partitioning along these dimensions that may reduce competition for resources. We tested for morphometric differences among the species, and for geographic and secondary sexual variation in each of the three species. Both wing and craniodental characters vary significantly among species. Artibeus fimbriatus exhibits sexual dimorphism in only one cranial character, and A. lituratus shows sexual dimorphism in three craniodental characters and in all wing characters, whereas A. planirostris is not sexually dimorphic in any character. Weak geographic variation was found in craniodental characters in A. planirostris, and in wing characters in the other two species. Differences were also encountered in the three species' morphometric responses to temperature and precipitation parameters. Evaluating these differences in morphometric patterns in the context of ecoregional and seasonal associations, migratory status and reproductive patterns, we conclude that the three species mitigate competitive pressure through a complex partitioning of available niche space.

Warming northward shifting southern limits of the iconic temperate seagrass (Zostera marina)

SummaryGlobal warming can shift the range edges of numerous species poleward. Here, eelgrass distribution was reinvestigated at its southern limits on the eastern coast of China, which indicated that there has been a northward shift in the southern limit of Z. marina. To determine if regional warming resulted in a northward shift in suitable eelgrass habitats, sixteen transplantations of adult eelgrass shoots and seeds at the historical southern distribution limit of eelgrass were conducted between 2016 and 2021. The results showed that high water temperatures in summer had negative effects on eelgrass growth, and directly triggered shoot mortality during 2016–2018. Under heat stress, antioxidant enzyme activity was initially increased, but then decreased under more stressful heat conditions; and the HSP70 protein and its molecular chaperone protein were highly expressed under heat stress. These results demonstrated that suitable eelgrass habitat was now located further north along the eastern coast of China.

Southern distribution limit of the European lobster, Homarus gammarus (Decapoda, Nephropidae) on the coast of northwest Africa with remarks on its habitat, and a new record from the Canary Islands

Southern distribution limit of the European lobster, Homarus gammarus (Decapoda, Nephropidae) on the coast of northwest Africa with remarks on its habitat, and a new record from the Canary Islands

Redescription of Anchoviella cayennensis (Puyo, 1945) (Clupeiformes: Engraulidae), with the synonymization of Anchoviella sanfranciscana Barbosa, Gomes da Silva, da Rocha Araújo & Carvalho, 2017 and remarks on Anchoviella perfasciata (Poey,1860).

Anchoviella cayennensis (Puyo, 1945) is a relatively small-sized, coastal and estuarine western Atlantic species of anchovy distributed from Suriname to southeastern Brazil. The species is morphologically similar to Anchoviella perfasciata (Poey, 1860) from the Central and western North Atlantic, and it has been suggested in the literature that both are actually synonyms. The recently described Anchoviella sanfranciscana (Barbosa et al., 2017) was reported as endemic to the estuary of the São Francisco River, northeastern Brazil. Most characters proposed as diagnostic for A. sanfranciscana in the description are, however, similar to the ones reported for A. cayennensis and A. perfasciata. To determine the complex taxonomic scenario involving the three species, 24 morphometric and 13 meristic characters of 171 specimens tentatively identified as A. perfasciata (including the holotype) and A. cayennensis from the Central and South Atlantic in addition to the holotype and 19 paratypes of A. sanfranciscana (total: 191 specimens) were analysed. The PCAs of morphometric characters indicate the existence of two groups, which are recognized as A. perfasciata and A. cayennensis, with A. sanfranciscana proposed as a junior synonym of the later. Further evidence from gill arch dentition also indicates that A. perfasciata and A. cayennensis are distinct valid species. A redescription of A. cayennensis is presented, with a neotype proposed for the species. Confirmation of the identity of specimens attributed to A. cayennensis indicates that its southern limitof distribution is in the Rio de Janeiro State, southeastern Brazil. An updated taxonomic key for the estuarine and coastal Atlantic species of Anchoviella is also presented.

Changing environment and orchid distributions close to their northern and southern limits in Britain

The total numbers of tetrad records in the BSBI database collected for 20 species of British orchids in the period 1970-86 were compared with those collected in 2010-19. The species chosen had a northern limit to their distributions somewhere in Britain and comparisons were restricted to changes close to their northern and southern distribution limits. In a 100 km band close to their northern limit, recorded tetrad occupancy decreased for 14 species by a mean of 34% between the two date-classes. Despite Britain warming by 0.9 C° over this period, four species had retreated southwards, and only Ophrys apifera (Bee Orchid) and Anacamptis pyramidalis (Pyramidal Orchid) had significantly extended their distributions northwards. Changes in tetrad occupancy were also explored in a similar band immediately to the north of the southern tip of the Isle of Wight. Here, tetrad occupancy decreased for 10 of the 20 species by a mean of 33%. In both the northern and southern bands, where a species was recorded in 1970-86, on average in 2010-19 it was re-recorded in only c.40% of tetrads. There were large differences between species in apparent rates of colonization of new tetrads. This accounted for most of the differences between species that increased their tetrad occupancy between the two date-classes and those that declined. No account was taken of the increase in the intensity of recording between 1970-86 and 2010-19 but these results provide further strong evidence of the decline of many orchid species, especially in England.

Species composition, distribution and relative abundance of the inshore fish community off the Argentine Islands, Bellingshausen Sea

In the last three decades, several interdisciplinary studies investigated the marine ecosystems off the West Antarctic Peninsula (WAP), one of the most impacted areas of the Southern Ocean by the global warming. Although the extent of near-shore habitats along the WAP is wider than elsewhere in Antarctica, the coastal fish communities have been rarely studied. Complementing these previous studies, we provide new data on the species composition, population structure and relative abundance of the inshore fish community living off the Argentine Islands (Bellingshausen Sea). Fish samples were caught all the year round during four different periods spread over ten years (from 2006 to 2017). The fish fauna consisted of fourteen high-Antarctic and low-Antarctic species of notothenioids, most of them belonging to the Nototheniidae. Notothenia coriiceps was by far the most abundant species, followed in decreasing abundance by Chaenocephalus aceratus, Notothenia rossii, Trematomus newnesi and Trematomus bernacchii. Our findings provide context for future ecological studies as this area represents either a spawning and nursery area for multiple species in this study. More generally, the inshore waters off the Argentine Islands represent the southern limit of distribution for several low-Antarctic species, and our results provide critical baseline data for assessing possible disruptions in population dynamics driven by the ongoing climate change.

Climate-change-driven growth decline of European beech forests

The growth of past, present, and future forests was, is and will be affected by climate variability. This multifaceted relationship has been assessed in several regional studies, but spatially resolved, large-scale analyses are largely missing so far. Here we estimate recent changes in growth of 5800 beech trees (Fagus sylvatica L.) from 324 sites, representing the full geographic and climatic range of species. Future growth trends were predicted considering state-of-the-art climate scenarios. The validated models indicate growth declines across large region of the distribution in recent decades, and project severe future growth declines ranging from −20% to more than −50% by 2090, depending on the region and climate change scenario (i.e. CMIP6 SSP1-2.6 and SSP5-8.5). Forecasted forest productivity losses are most striking towards the southern distribution limit of Fagus sylvatica, in regions where persisting atmospheric high-pressure systems are expected to increase drought severity. The projected 21st century growth changes across Europe indicate serious ecological and economic consequences that require immediate forest adaptation.

Local adaptation of juvenile giant kelp, Macrocystis pyrifera, from their southern limit in the northern hemisphere explored using reciprocal transplantation

ABSTRACT The Pacific coast of the Baja California peninsula (Mexico) is a unique biogeographic transition zone, where many kelp species encounter their southern subtropical limits and have experienced a range contraction in the northern hemisphere. Using reciprocal transplant experiments with giant kelp populations from their southern limit and a northern temperate site on the Baja California peninsula, we hypothesized that juveniles from the southern site would grow longer, have more fronds (an individual stipe with its blades), and have higher photosynthetic efficiency (α) and blade tissue nitrogen, especially under warmer nitrate-limited field conditions experienced in their habitat. At the southern-limit transplant site, local juveniles had more fronds compared with those from the north after 90 days in field conditions (warm waters). At the northern transplant site, blade tissue nitrogen of juveniles from both populations was low after 23 days in field conditions (not significantly different during a warm water period), however, after a further 56 day cooling period and shortly after a strong upwelling event, juveniles from the southern population had greater blade tissue nitrogen concentrations than those from the north, which showed little change. Respiration and a were both greater at higher temperatures in juveniles from the southern population, and this pattern was maintained under warm water field conditions. These physiological differences in conspecific juveniles from different populations may be driven by population-level adaptation to frequently occurring thermal and nutrient stress in southern Baja California, which is the southern distribution limit for giant kelp. Further exploration of population level differences in ecophysiology should be applied to kelp forest restoration efforts as oceans warm.

Are southern pine forests becoming too warm for the southern pine beetle?

Climate change is altering the geographic distribution of many species, including numerous forest insect pests, with the potential for severe impacts to forest ecosystems. The southern pine beetle (Dendroctonus frontalis), one of the world's most persistently destructive forest pests, has extended its distribution towards the north, while impacts within its historic range in the southeastern United States have diminished, indicating that a range shift may be occurring. This pattern could be explained by the hypothesis of climatic envelopes if summers in the southern part of the range are warming about as much as winters in the northern part of their range. Here, we tested whether the southeastern United States is becoming too hot for D. frontalis even as the northeastern United States has become climatically permissive. We measured effects of heat on insect survival, and characterized the thermal environment of D. frontalis, including estimating the frequency of potentially lethal heat waves and testing whether the intensity or duration of heat waves has increased over the past 80 years. We found that temperatures warm enough to kill D. frontalis larvae, pupae, or callow adults have been rare or absent and that there has been no change in the duration or severity of heat waves in the southern pine forest region over the last 80 years. Therefore, alternative explanations for the reduced activity of D. frontalis within its historic range must be considered. The broad conclusions are not restricted to D. frontalis because they flow from an asymmetry in climate change: at least for now in eastern North America, the coldest winter temperatures have been becoming less extreme without summer heat becoming more extreme. This creates broad potential for northward range expansions without expectation of corresponding contractions in southern distribution limits.

Drivers and Dynamics of Foliar Senescence in Temperate Deciduous Trees at Their Southern Limit of Distribution in Europe

Drivers and Dynamics of Foliar Senescence in Temperate Deciduous Trees at Their Southern Limit of Distribution in Europe

MODEL FOR MANAGEMENT AND PLANNING OF FISHING PLAYFUL-SPORTS IN THE RIVER MOURO HYDROGRAPHIC BASIN

The Institute for the Conservation of Nature and Forests (ICNF) has recently carried out work on planning and management of recreational fishing in the area of ​​the Mouro River drainage basin — a mountain watercourse in the North of Portugal (River Hydrographic Basin). Minho) which is born near the place of Lagarto (Lamas de Mouro, Melgaço), in the Peneda-Gerês National Park (PNPG). The model adopted was initially implemented (2008) to manage that activity in the Olo river basin (BH of the Douro river), and this methodology also served as a foundation for creating in 2020 in the Northeast region of Trás-os-Montes (Mente rivers, Rabaçal and Tuela – Vinhais and Bragança) plus three recreational fishing areas. In this context, 13 sampling stations were set up (12 in the Mouro river and 1 in the Sucrasto river), considered representative of a large part of the habitats that make up this study area, where actions were carried out to monitor the ichthyofauna (electrical fishing) and hydromorphological characterization of habitats (River Habitat Survey, RHS). The monitoring of benthic macroinvertebrates was an additional action, recently introduced in this type of work, aimed at improving the biological assessment of water quality and aquatic ecosystems and which is serving as a basis for the preparation of a Master's Thesis. With this study, data was analyzed concerning age, growth, physical condition of the monitored specimens, as well as their relationship with the different types of habitats where they were captured. To detect spatial distribution patterns underlying biotic (species/abundance and species/ages) and environmental data, multivariate methods can be used. As a result of this work, the Ludic Fishing Zone (ZPL) of the Mouro River (and its tributaries) will be created, with the aim of promoting recreational and sport fishing based on more conservationist principles. With this initiative, ICNF intends to guarantee greater protection and sustainability of endogenous aquaculture resources, with particular emphasis on the case of Atlantic salmon (Salmo salar). This salmonid annually elects a significant part of these continental waters to complete its reproductive phase. However, other studies, in this context, should be developed to better understand the ecology of the species in a country that coincides with its southern limit of distribution in Europe.

Differential responses of coexisting owls to annual small mammal population fluctuations in temperate mixed forest

Montane temperate forests in central and southern Europe host diverse small mammal assemblages, but the fluctuations in these assemblages in correlation with owl predators are still poorly explored. The key questions of our study were how coexisting owls responded to different prey fluctuations and whether any particular small mammal species governed predator–prey co‐dynamics. We conducted a long‐term study (2004–2020) in low‐elevation (300–1100 m above sea level) mixed Beech and Silver Fir forest in the northern Dinaric Alps (central Slovenia). Monitoring data on the main small mammal groups – mice Muridae, voles Cricetidae, dormice Gliridae and shrews Soricidae – and three owl species – the Ural Owl Strix uralensis, Tawny Owl Strix aluco and Boreal Owl Aegolius funereus – were collected annually. To find relationships between prey and predator populations, we used two types of supervised machine learning approaches and addressed three predictive modelling tasks of multi‐target regression. The dominant species in the small mammal assemblage, the Yellow‐necked Mouse Apodemus flavicollis, had a key role in determining predator populations and their breeding performance. We noted higher sensitivity to small mammal fluctuations in boreal zone owl species (Boreal Owl and Ural Owl), which reach their southern distribution limit in the Dinaric Alps, whereas the temperate zone species (Tawny Owl) seemed to be less affected. In years of prey shortage, the Boreal Owl was found to presumably abandon its territories, the Ural Owl suppressed breeding and the Tawny Owl sustained breeding activity by shifting prey selection. Low‐elevation forests appeared to be suboptimal habitat for the competitive subordinate Boreal Owl, which may exploit occasional outbreaks of small mammal populations in these habitats even in the presence of larger competitors. Whether low‐elevation forests can play a role in maintaining threatened and cold‐adapted Boreal Owl populations in central and southern Europe in the face of recent ecosystem changes due to climate and environmental changes remains an open scientific question.

Fucoid Macroalgae Have Distinct Physiological Mechanisms to Face Emersion and Submersion Periods in Their Southern Limit of Distribution

During high tide, macroalgae are submersed, facing adequate environmental conditions, however, at low tide, these species can be exposed to high UV radiation and desiccation, leading to an overproduction of reactive oxygen species, causing oxidative stress. Since intertidal organisms present differential sensitivity to abiotic fluctuations, this study aimed to evaluate the physiological responses [photosynthetic pigments, hydrogen peroxide (H2O2), lipid peroxidation (LP), and thiols and proline] of three macroalgae, from different intertidal levels, towards tidal regimes. Samples of Pelvetia canaliculata, Ascophyllum nodosum, and Fucus serratus were collected from beaches located on the southern limit of distribution in periods of potential stress (Summer and Spring), under low and high tide. The photosynthetic pigments of P. canaliculata and F. serratus were generally higher during low tide, and the oxidative damage evidenced by H2O2 and LP increased in the Summer, while A. nodosum showed greater oxidative damage in the Spring. While thiol content did not change, proline levels were species- and tidal-specific among sampling dates. P. canaliculata presented higher resilience to unfavorable conditions, while F. serratus was the most sensitive species. The physiological responses analyzed were species-specific, pointing to the high susceptibility of low intertidal organisms to expected extreme climatic events.

Brazilian Semi-Arid Mangroves-Associated Microbiome as Pools of Richness and Complexity in a Changing World.

Mangrove microbiomes play an essential role in the fate of mangroves in our changing planet, but the factors regulating the biogeographical distribution of mangrove microbial communities remain essentially vague. This paper contributes to our understanding of mangrove microbiomes distributed along three biogeographical provinces and ecoregions, covering the exuberant mangroves of Amazonia ecoregion (North Brazil Shelf) as well as mangroves located in the southern limit of distribution (Southeastern ecoregion, Warm Temperate Southwestern Atlantic) and mangroves localized on the drier semi-arid coast (Northeastern ecoregion, Tropical Southwestern Atlantic), two important ecotones where poleward and landward shifts, respectively, are expected to occur related to climate change. This study compared the microbiomes associated with the conspicuous red mangrove (Rhizophora mangle) root soils encompassing soil properties, latitudinal factors, and amplicon sequence variants of 105 samples. We demonstrated that, although the northern and southern sites are over 4,000 km apart, and despite R. mangle genetic divergences between north and south populations, their microbiomes resemble each other more than the northern and northeastern neighbors. In addition, the northeastern semi-arid microbiomes were more diverse and displayed a higher level of complexity than the northern and southern ones. This finding may reflect the endurance of the northeast microbial communities tailored to deal with the stressful conditions of semi-aridity and may play a role in the resistance and growing landward expansion observed in such mangroves. Minimum temperature, precipitation, organic carbon, and potential evapotranspiration were the main microbiota variation drivers and should be considered in mangrove conservation and recovery strategies in the Anthropocene. In the face of changes in climate, land cover, biodiversity, and chemical composition, the richness and complexity harbored by semi-arid mangrove microbiomes may hold the key to mangrove adaptability in our changing planet.