An efficient low-cost method for sampling floral visitors on down-facing flowers

Pollinators are traditionally considered to be the primary agent of selection on floral traits. However, floral traits may also be under selection from abiotic agents (e.g. rain), which makes considering the relative importance of pollinators and abiotic selective agents on floral traits essential. The functional significance of floral orientation is often ascribed to pollinator attraction, but orientation can also protect reproductive structures from rain. Therefore, a study that incorporates both factors will enhance our understanding of the ecological roles of floral orientation in plant fitness. Mertensia brevistyla and M. fusiformis are herbaceous species that differ in their floral orientations. A series of field and laboratory experiments was used to investigate the adaptive function of floral orientation in these species, particularly with respect to pollinators and rain. We measured and compared floral orientation and visitor assemblages between M. brevistyla and M. fusiformis populations in western Colorado, USA. We manipulated floral stems and conducted a choice experiment with floral visitors, and also compared orientations of pollinator-visited stems with those of unvisited stems in a natural setting. We examined pollinator- and rain-mediated selection on floral orientation by manipulating orientation, conducting supplemental pollinations, applying watering treatments and measuring subsequent seed set. We also experimentally tested the likelihood of rain contact with anthers, and the effect of rainwater on pollen germinability. Mertensia brevistyla had a significantly more upright floral orientation than M. fusiformis, and seed set was highest in upright M. brevistyla and in horizontal/pendant M. fusiformis stems, supporting an adaptive function (via female fitness) of the interspecific difference in orientation. However, floral visitor assemblages did not differ significantly between the two species; visitors did not exhibit significant preference for either orientation; and pollinator-mediated selection on orientation was undetectable. Similarly, there was little effect of water on seed set in either species, regardless of floral orientation. However, pollen germinability was reduced in both species by immersion in water; and water was more likely to contact anthers in M. fusiformis than in M. brevistyla, due to interspecific differences in floral morphology. We conclude that pollinators are likely not the primary selective agent driving differences in orientation in these Mertensia species. Instead, the negative effect of rain on pollen germinability helps explain the more pendant orientation of M. fusiformis, while short anthers in more upright M. brevistyla provide an alternative adaptation to rain. The selective agent driving effects of orientation on seed set remains unclear. This study illustrates the necessity of considering male fitness and abiotic agents in interpreting the functional significance of inflorescence traits.

Actinomorphic flowers usually orient vertically (relative to the horizon) and possess symmetric nectar guides, while zygomorphic flowers often face horizontally and have asymmetric nectar guides, indicating that floral symmetry, floral orientation, and nectar guide patterning are correlated. The origin of floral zygomorphy is dependent on the dorsoventrally asymmetric expression of CYCLOIDEA (CYC)-like genes. However, how horizontal orientation and asymmetric nectar guides are achieved remains poorly understood. Here, we selected Chirita pumila (Gesneriaceae) as a model plant to explore the molecular bases for these traits. By analyzing gene expression patterns, protein-DNA and protein-protein interactions, and encoded protein functions, we identified multiple roles and functional divergence of 2 CYC-like genes, i.e. CpCYC1 and CpCYC2, in controlling floral symmetry, floral orientation, and nectar guide patterning. CpCYC1 positively regulates its own expression, whereas CpCYC2 does not regulate itself. In addition, CpCYC2 upregulates CpCYC1, while CpCYC1 downregulates CpCYC2. This asymmetric auto-regulation and cross-regulation mechanism might explain the high expression levels of only 1 of these genes. We show that CpCYC1 and CpCYC2 determine asymmetric nectar guide formation, likely by directly repressing the flavonoid synthesis-related gene CpF3'5'H. We further suggest that CYC-like genes play multiple conserved roles in Gesneriaceae. These findings shed light on the repeated origins of zygomorphic flowers in angiosperms.

Pan traps: An effective tool for monitoring phenological changes in insect floral visitors and their relationship with floral resources in a coastal Mediterranean forest

Peacock bass (Ciclha kelberi) has been introduced in reservoirs in Brazil; however, information about its reproductive aspects and gonadal maturation remains scarce. Studies on this field carried out in Maranhão State, Brazil mainly address information from lakes and specific regions. The aims of the present study are to feature the gonads and female germ cells of C. kelberi captured in a basin by Lençóis Maranhenses National Park. Thirty specimens were collected, euthanized and weighed. Their gonads were subsequently removed and taken to histological processing. Females were classified as synchronous in multiple batches. Germ cells were featured as Primordial Follicles, Primary Development, Cortical Alveoli, Lipid Vitellogenesis, Lipid-Protein Vitellogenesis and Complete Vitellogenesis. Post-ovulatory and Atretic Follicles were also observed. The smallest cell (in diameter) was observed in primordial follicle cells (16.7 µm) and the largest one was recorded for atretic follicle cells (453.5 µm). The smallest cell area was 580.9 µm2 and the largest one was 300,240.7 µm2. The collected data differed from those recorded other reservoirs in Maranhão State and for other locations in Brazil. This finding points out that this species remains under adaption to the lotic environment in Preguiças River, at Lençóis Maranhenses National Park. Additional research is necessary to help better understanding the long-term reproductive and ecological aspects of the assessed species in order to support the sustainable management of this basin.

Evaluation of anthropogenic impacts on marine turtle populations in Lençóis Maranhenses National Park.

In increasingly urban landscapes, the loss of native pollen and nectar floral resources is impacting ecologically important pollinators. Increased urbanization has also brought about the rise of urban gardens which introduce new floral resources that may help replace those the pollinators have lost. Recently, studies have shown that the microbial communities of nectar may play an important role in plant-pollinator interactions, but these microbial communities and the floral visitors in urban environments are poorly studied. In this study we characterized the floral visitors and nectar microbial communities of Ascelpias curassavica, a non-native tropical milkweed commonly, in an urban environment. We found that the majority of the floral visitors to A. curassavica were honey bees followed closely by monarch butterflies. We also found that there were several unique visitors to each site, such as ants, wasps, solitary bees, several species of butterflies and moths, Anna’s hummingbird, and the tarantula hawk wasp. Significant differences in the nectar bacterial alpha and beta diversity were found across the urban sites, although we found no significant differences among the fungal communities. We found that the differences in the bacterial communities were more likely due to the environment and floral visitors rather than physiological differences in the plants growing at the gardens. Greater understanding of the impact of urbanization on the nectar microbiome of urban floral resources and consequently their effect on plant-pollinator relationships will help to predict how these relationships will change with urbanization, and how negative impacts can be mitigated through better management of the floral composition in urban gardens.

BackgroundThe Lençóis Maranhenses National Park, located in Maranhão, Brazil, is a region of exceptional beauty and a popular tourist destination. The adjoining area has suffered from the impact of human activity and, consequently, has experienced outbreaks of leishmaniasis. This study aimed to evaluate the composition, abundance, species richness and seasonal distribution of sand flies in the region and to determine the constancy of the insect population.MethodsThe survey was conducted at three sites located in the municipalities of Barreirinhas and Santo Amaro between September 2012 and August 2013. Sampling was performed monthly using automatic light traps installed 1.5 m above the soil adjacent to 13 randomly selected rural dwellings. At each site, one trap was placed in the peridomicile near to animal enclosures and another (extradomicile) at 500 m from the peridomicile.ResultsA total of 4,474 individual sand flies were collected over the year with the highest abundance recorded during the rainy season (December to June). Nine species were collected: L. whitmani, L. longipalpis, L. lenti, L. sordellii, L. evandroi, L. flaviscutellata, L. wellcomei, L. termitophila and L. intermedia. Although peridomiciliary and extradomiciliary environments presented similar species richness, the Shannon diversity index was significantly lower in the former (H’ = 2.4) compared with the latter (H’ = 4.98). Lutzomyia whitmani and L. longipalpis were the most abundant species and were classified as constant (constancy index, CI = 100 %) along with L. lenti (CI = 58.3), L. evandroi (CI = 58.3) and L. sordellii (CI = 66.7). The remaining four species presented CI values between 25 and 50 % and were considered accessory.ConclusionsThe present results confirm the present of L. whitmani and L. longipalpis in the peridomicile of houses in Lençóis National Park. The abundance of these species could explain, respectively, the endemicity of cutaneous leishmaniasis and sporadic cases of visceral leishmaniasis in the study area. However, in the case of cutaneous leishmaniasis, the presence of other sand fly vectors (in addition to L. whitmani) cannot be neglected. Finally, this study emphasizes the need for a more effective and permanent supervision to control the expansion of these vectors and leishmaniasis outbreaks.

The Cerrado, the world’s most diverse savanna, has several adaptations to fire. However, intense and frequent fires, especially after frosts, can severely impact this ecosystem. Despite this, few studies have evaluated the combined effects of frost followed by fire. We investigated how these disturbances affect plant traits, floral resources, floral visitor richness, and the structures of plant–pollinator interaction networks by using Byrsonima intermedia, a common Malpighiaceae shrub, as a model. We compared areas affected by frost alone and frost followed by fire and the same fire-affected area two years later. We examined pollen, oil volume, buds, and racemes and recorded floral visitors. Our main hypothesis was that fire-affected areas would exhibit higher floral visitor richness, more conspicuous plant traits, and greater fruit production than areas affected by frost only, which would show higher interaction generalization due to stronger negative impacts. The results confirmed that frost drastically reduced floral traits, visitor richness, and reproductive success. In contrast, fire facilitated faster recovery, triggering increased floral resource quantities, richer pollinator communities, more specialized interactions, and greater fruit production. Our findings highlight that fire, despite its impact, promotes faster ecosystem recovery compared to frost, reinforcing its ecological role in the Cerrado’s resilience.

Numerous sand fly species have been reported in Lençóis Maranhenses National Park (LMNP) in Northeast Brazil, including important Leishmania vectors, making the park an endemic area for tegumentary and visceral leishmaniasis. We evaluated sand fly abundance monthly over 7 years, correlating it with environmental variables and monthly tourist numbers in LMNP. Sand fly species were observed throughout the year, with Lutzomyia longipalpis Lutz & Neiva and Nyssomyia whitmani Antunes and Coutinho (Diptera: Psychodidae) being the most abundant species, especially from April to June. In addition to seasonal abundance patterns, Lu. longipalpis showed increasing abundance throughout 2013 until April 2014, whereas Ny. whitmani exhibited a consistent increase throughout the study period. Redundancy analysis indicated that monthly sand fly abundances increased with humidity but decreased with mean temperature and wind speed. Ecotourists mainly visit the park from May to September when interdune lagoons are full, coinciding with high-frequency vector activity during the rainy months (May-June). Tourists also visit in January and February during school holidays, when the rains begin and sand fly abundance increases, and in July, when sand fly abundance decreases. To date, no instances of infected tourists have been recorded, likely because visits to LMNP occur during the day when sand flies are inactive. However, there is a potential risk of vector exposure if tourists engage in nighttime cultural visits to villages around the park, where leishmaniasis cases occur annually.

Sand flies are very common in the region of Lençóis Maranhenses National Park, an important tourist attraction in Brazil. However, the role of some species and their relative importance locally in Leishmania Ross 1903 transmission is unclear. The objective of this study was to identify Leishmania infection in phlebotomine sand flies collected around the Lençóis Maranhenses National Park, an important conservation area and popular international/national tourist destination with a high incidence of leishmaniasis. Sand flies were collected in peridomiciliary areas on the tourist route from September 2012 to August 2013. The captured females were subjected to molecular analyses for the detection of Leishmania DNA. Sand flies were infected with four Leishmania species: Leishmania (Viannia) braziliensis (Vianna, 1911) was found in Lutzomyia whitmani (Antunes and Coutinho, 1939) (2.1%) and Lutzomyia longipalpis (Lutz and Neiva, 1912) (1.7%); Leishmania (Leishmania) infantum (Nicole, 1908) infected Lutzomyia wellcomei (Fraiha, Shaw, and Lainson, 1971) (20%), Lutzomyia sordellii (Shannon and Del Ponte, 1927) (4.3%), Lu. longipalpis (3.7%), and Lu. whitmani (0.8%); Leishmania (Leishmania) amazonensis (Lainson & Shaw, 1972) was found in Lu. whitmani (0.58%), while Leishmania (Viannia) lainsoni infected Lutzomyia evandroi (Costa Lima and Antunes, 1936) (3.4%), Lu. longipalpis (1.06%), and Lu. whitmani (0.29%). The occurrence of these parasites requires control measures to reduce the incidence of cutaneous leishmaniasis and to contain a possible epidemic of visceral leishmaniasis, the most severe form of the disease.

Local ecological knowledge is transmitted across generations and arises from various human interactions with the environment. Cultural and socioeconomic variables such as age, sex, educational level and locality can influence both the acquisition and transmission of this knowledge. However, Brazil's diverse environmental contexts reveal gaps in information regarding interactions with local fauna. Given this scenario, this study aims to investigate whether socioeconomic factors influence knowledge about reptile and mammal species in Lençóis Maranhenses National Park. Additionally, it seeks to provide a list of the recognized animals and document interactions between residents and fauna. Data were collected through semi-structured questionnaires and open-ended interviews, resulting in records of 36 species (plus 6 identified only at genus level) in 33 families and 10 orders, of which 53% were non-avian reptile and 47% mammals. We observed three types of interactions between residents and fauna: dietary, medicinal and conflict-related. Among the variables analyzed using a generalized linear model, only locality significantly influenced traditional faunal knowledge in the communities studied.

(Taxonomic study of the Bromeliaceae in Lençóis Maranhenses National Park, MA, Brazil). The Lençóis Maranhenses National Park (PNLM) is located in the eastern region of the coast of the state of Maranhão, Northeastern Brazil, through the municipalities of Barreirinhas, Santo Amaro, and Primeira Cruz. It has an area of 155,000 hectares, with gently undulating relief and altitudes of less than 100 m. The vegetation is composed of a mosaic involving Mangrove, Cerrado and Restinga. Part of the Park is covered by a vast area of sand dunes, which form huge pools during the rainy season. Fieldwork was carried out in the municipalities of Barreirinhas and Santa Amaro. The testimonial material is deposited in the Maranhão Continental Herbarium (BMA). Four species in three genera were found: Aechmea (1 sp.), Ananas (1 sp.) and Bromelia (2 spp.). Identification key, descriptions, photographs, and ecological, taxonomic and geographic distribution comments are presented for each species located in the Park.

The Wild Boar is one of the world’s most dangerous invasive species. It is now established in many regions beyond its native range, including many Brazilian states. However, the species has never been recorded from the Brazilian state of Maranhão. Here, we report the first occurrence of this species from Lençóis Maranhenses National Park, within the municipality of Barrerinhas, Maranhão state. We discuss the negative effects of this introduction on native species, including the problem with predation of nests of an endangered turtle species by Wild Boar.

Gentrification, refers to a series of transformations in strategic areas with the aim of redeveloping spaces and encouraging the reoccupation of these areas for economic gain. In Brazil, this phenomenon also occurs in coastal regions with tourist potential, protected areas and regions occupied by traditional peoples and communities, resulting problems and socio-environmental conflicts. This is what is happening today in the Lençóis Maranhenses National Park, created in 1981, overlapping territories traditionally occupied by families of traditional communities. Initiatives by the state and by political and economic agents aimed at transforming this place-territory into a tourist site have led, among other implications, to a process of gentrification of traditionally occupied territories. The aim of this paper is to analyze the process of gentrification in some traditional communities in the Lençóis Maranhenses National Park, occupied by families who have had their places of residence and work converted into tourist destinations. In this scenario, gentrification is expressed in transformations to the landscape, intensification of speculation, pressure on the use of historically managed natural resources and changes to traditional forms of sociability. It is also reaffirmed by the introduction of architectural patterns that differ from those that exist locally, an increase in the cost of living for traditionally resident families, and lifestyles and social behaviors that differ from the native way of life. Based on a qualitative methodology, this work is anchored in ethnographic information from fieldwork consolidated through direct and participant observation.

Brazil harbors the second largest expanse of mangroves in the world, trailing only behind Indonesia. In a regional context, the state of Maranhão stands out, encompassing approximately 36% of Brazil’s total mangrove area, including a portion located on the eastern coast in the Lençóis Maranhenses. This study played a crucial role in identifying the areas of gain, loss, and stability in the mangroves surrounding the Lençóis Maranhenses National Park over a historical period spanning from 1985 to 2019. The study provided detailed maps depicting spatial changes, such as migration and attenuation that occurred in the mangroves due to the influence of aeolian dunes and wind patterns in the region. This long-term analysis, the first of its kind to examine the annual expansion of forest loss in the remaining mangroves around the Lençóis Maranhenses in recent decades, revealed a reduction in the central mangrove areas between 1985 and 2019. This decline can be attributed not only to intense tourist activity and climate change but also to the movement and invasion of sand dunes in certain areas, as observed near the villages of Caburé and Paulino Neves (Pequenos Lençóis) in December2022. Wind plays a fundamental role as a transformative agent in the local landscape. Through the analysis of wind roses using ERA5 reanalysis data and meteorological stations from the Aeronautics (São Luís and Parnaíba), it was possible to identify and characterize the prevalence of northeast trade winds in the Lençóis Maranhenses region during the years 1985 to 2019, with average speeds ranging from 6 to 8 m/s. The advancement of dunes onto the mangroves surrounding the Lençóis Maranhenses results in burial, reduction, and even migration of mangrove patches. Additionally, over the years, population growth and increasing tourism pressure along the banks of the Preguiças River have drawn attention to the need to implement control and conservation measures in the mangroves to prevent further disturbances in this environment.