Abstract in English:

Abstract Parablechnum is a genus in the fern family Blechnaceae that exhibits wide morphological variation without a distinct taxonomic discontinuity. To address this problem, we applied the technique of Elliptic Fourier Analysis to evaluate leaf shape by calculating Fourier harmonics based on coordinates derived from a closed outline. Using a combination of contour extraction software and the Momocs package in R, it was possible to analyze 102 specimens of Parablechnum using the pinna as the analytical component, due to its ease of visualization in digitized herbarium specimens. Among the six studied species, three distinct groups were identified using LDA and PCA, with one group consisting exclusively of Parablechnum cordatum. This analysis reaffirmed the segregation found in other studies, helped resolve the P. cordatum complex. This technique enables the use of digitally available herbarium materials, offering the possibility of identifying old specimens and evaluating taxonomic variation in cases like Parablechnum.

Abstract in English:

Abstract This study analyzes the leaf morphoanatomy of representatives of the Chapada Diamantina clade (Asteraceae, Eupatorieae) to identify anatomical characters that aid in the taxonomic delimitation of the group. Leaves from 16 species across six genera were examined, focusing on epidermis, mesophyll, vascular system, and trichomes. The results indicate adaptations to the Campo Rupestre environment, including a thick cuticle, high trichome density, stomatal crypts, and multiseriate parenchyma, suggesting a hypodermis of ground meristem origin and sclerenchyma sheath extensions. We scored 27 structural characters and mapped them onto the most recent phylogenetic tree recovered for the clade. The positioning of secretory ducts in the midrib may represent a synapomorphy of the clade. The presence of isobilateral mesophyll and sclerenchyma fibers in Agrianthus and Arrojadocharis reinforces their phylogenetic proximity. Semiria sp. nov. and Semiria viscosa share convergent anatomical traits, but key structural differences support their generic separation. Additionally, Bishopiella elegans is distinguished by homogeneous mesophyll and absence of mechanical support tissues, whereas Lasiolaena and Stylotrichium exhibit revolute margins and multistratified hypodermis. These findings highlight the relevance of leaf anatomy in taxonomic and evolutionary studies, supporting previous phylogenetic hypotheses and emphasizing the importance of integrating morphoanatomical and molecular data in the classification of Asteraceae.

Abstract in English:

Abstract Microsatellite markers (SSR) are still largely used to assess the reproductive system and genetic diversity in plant populations. Although the timber tree Amburana cearensis (Fabaceae) is endangered, according to the IUCN classification, there are no effective management and conservation plans being implemented for the species. It occurs exclusively in South America, predominantly in Seasonally Dry Tropical Forests, such as Caatinga and Chaco, but also in savanna areas of the Cerrado. The negative effect of large human populations on the biodiversity of these regions is likely to be more pronounced for endangered species such as A. cearensis. We developed SSR markers, tested their transferability to Amburana-related genera, and described the genetic diversity of A. cearensis in Brazilian dry forests. The number of alleles per locus ranged from two to 11. Eight loci showed significant deviation from HWE. The genetic differentiation was low to moderate (F ST = 0.0972, p < 0.001), suggesting some gene flow among populations. Two loci were widely transferable to related genera. The developed SSR markers can be useful to study the reproductive biology and genetic diversity, and may therefore support more effective conservation strategies for A. cearensis by the inclusion of genetic information.

Abstract in English:

Abstract Cymodocea rotundata, a tropical seagrass abundant in Southeast Asia, exhibits considerable morphological plasticity. However, consistent morphological differences among populations may reflect genetic divergence potentially influenced by local environmental conditions, particularly in geographically isolated systems. We examined populations from two offshore Vietnam islands , Ly Son (more disturbed) and Phu Quy (less impacted), using morphological traits, biomass measurements, nuclear SSR markers, and chloroplast haplotypes (trnL-trnF). Morphological and biomass analyses revealed clear differences between islands: Phu Quy exhibited significantly longer and wider leaves, greater sheath length, and taller shoots, while Ly Son individuals had thicker rhizomes and higher below-ground biomass, suggesting phenotypic differentiation associated with contrasting environmental conditions. Although the SSR polymorphism was limited, the results indicated moderate differentiation and higher intra-population variability in Ly Son. Chloroplast sequencing of nine individuals identified four haplotypes, including both shared and island-specific lineages, with Ly Son exhibiting higher haplotype diversity. Together, these results support the recognition of Ly Son and Phu Quy as distinct conservation units. Overall, populations from both islands appear vulnerable to coastal development and environmental change, highlighting the need for site-specific conservation strategies to preserve their genetic and morphological diversity.

Abstract in English:

Abstract Across the tropical Atlantic, morphologically similar vascular plants suggest the action of vicariance and dispersal processes. Robbin C. Moran & Alan R. Smith’s research documented this pattern for ferns and lycophytes, particularly within Polypodiaceae. This study aims to determine the evolutionary history and biogeographical relationships of Polypodiaceae species between tropical America and Afrotropics. Using the floristic relationships proposed by Moran & Smith, a dated maximum-credibility topology was constructed with 113 species distributed in 24 genera. A presence-absence matrix was created for each species per bioregion, and biogeographical inferences were made using the BioGeoBEARS package in R. Six possible models were tested, and Stochastic Biogeographic Mapping (BSM) was used to estimate biogeographic events. Most proposed floristic relationships were corroborated by previous studies, except Microgramma lycopodioides (tropical America) and M. mauritiana (Afrotropics), explained by evolutionary convergence. Sympatric speciation and dispersal were the most frequent events, with Central and South America as the main source. Long-distance dispersal events, though less frequent, were crucial for the evolution and establishment of species on new continents, shaping current biogeographical patterns. These findings highlight the importance of understanding biogeographical processes in interpreting global plant diversity and distribution.

Abstract in English:

Abstract The anatomical characterization of mangaba fruit at different developmental stages remains largely unexplored. This study aims to describe the anatomical features of the mangaba pericarp across distinct phenological stages. Conventional anatomical techniques were employed for fruit characterization, along with histochemical assays. Throughout all developmental stages, the exocarp remains uniseriate and bears stomata and papillae; however, only the cuticle undergoes substantial changes, being thin during the early stages and becoming thicker as development progresses. As ripening progresses, the cuticle becomes thicker. The mesocarp is divided into three regions: outer, middle, and inner. In the outer region, the parenchyma cells elongate in the periclinal direction and display a denser organization. Idioblasts containing phenolic compounds are more abundant at the onset of fruit development but decrease as the fruit matures. Articulated and anastomosed laticifers occur throughout the middle mesocarp, along with concentric and collateral vascular bundles, whose vessel elements exhibit a helical pattern. In the endocarp, elongated trichomes develop as the fruit ripens. The pericarp analysis enabled the description of key structures associated with the survival and perpetuation of the species. Moreover, it provides valuable insights for postharvest studies of the fruit.

Abstract in English:

Abstract Understanding and conserving wetland vegetation requires a unified framework for classifying plants adapted to aquatic environments. Numerous taxonomic, limnological, and ecological studies have endeavored to establish such a framework. From Eugenius Warming's pioneering work to the latest classifications, this paper provides a historical overview of the various terms, concepts, and criteria used to categorize these plants, considering environmental factors, evolutionary relationships, and functional traits. The biological forms associated with adaptations to flooding, including floating and submerged species, offer valuable insights into the diverse life strategies of aquatic plants within the land-water continuum. This review thoroughly examines the definition of amphibious plants, a complex group that reflects the diversity of landscapes in which they occur, often resulting in sampling biases over time. These plants, reliant on water to complete their life cycle, are adapted to fluctuating water levels typical of waterway margins and exhibit phenotypic plasticity in response to varying degrees of soil water saturation. Finally, we discuss key considerations for sampling techniques to better investigate amphibious plants, such as sampling in different seasons and analyzing hydrological fluctuations in the studied region.

Abstract in English:

Abstract Contradictions were observed in a recent analysis of the ranges of two new Passiflora species described for Brazil, Passiflora itatiaiensis and P. pardifolia, raising questions concerning that author’s knowledge of the physical geography of Brazil and South America, as well as adherence to Brazilian legislation regulating the collection of plant specimens. Additionally, an examination of the material available in the herbarium collections cited for these species revealed a new record of P. itatiaiensis, expanding its known range.

Abstract in English:

Abstract The Myrtaceae is rich in phenolics and volatile terpenoids and has many reported associations with gall inducers in Brazilian restinga. These metabolites protect plants against both biotic and abiotic stresses, but also play a crucial signaling role in plant-herbivore interactions, especially on superhosts like Neomitranthes obscura. We hypothesize that the chemical identity of the superhosts relates to their capacity to respond to diverse galling herbivores, which was assessed through a two-step bibliographic survey resulting in 52 analysed documents. The prevalent classes of chemical compounds in the superhost Myrtaceae are hydrocarbonated (SH) and oxygenated sesquiterpenes (OS), which are related to plant identity and its interactions with the galling organisms. Among the superhost Myrtaceae, Neomitranthes obscura shares sesquiterpenic and phenolic derivatives with other host plants, which makes it impossible to infer why some species are superhosts while others are not. Our results suggest that a greater diversity of terpenoids may be related to metabolic flexibility, potentially increasing the ability of hosting galling species. However, further research is needed to explore this relationship, particularly in conjunction with other key metabolite classes in Myrtaceae, such as phenolic compounds.

Abstract in English:

Abstract Despite the ecological importance of marine macroalgae, molecular studies on green and brown algae in Brazil remain limited in scope and continuity. This review presents a scientometric analysis of DNA sequences deposited in GenBank from 1998 to 2023, focusing on Brazilian specimens of Ulvophyceae and Phaeophyceae. We identified 304 sequences: 202 from Ulvophyceae and 102 from Phaeophyceae, produced by 17 institutions, with only six of these being Brazilian. The data reveal regional asymmetries, with most contributions concentrated in Southeastern and Northeastern regions of Brazil. Although more than 40 molecular markers have been employed, the most common were rbcL, tufA, and cox1. The absence of specimen voucher codes and incomplete metadata in many submissions highlights significant challenges in data quality and reproducibility. Compared to red algae (Rhodophyta), for which thousands of sequences exist, green and brown macroalgae remain understudied. Our findings underscore the urgent need to invest in researcher training, strengthen institutional collaboration, and improve the quality and sampling coverage of molecular data. Such actions are crucial for advancing the taxonomy, systematics, and conservation of Brazilian macroalgal biodiversity.

Abstract in English:

Abstract The traditional representation of the water cycle often overlooks the active role of vegetation in absorbing atmospheric moisture, rendering it incomplete. This oversight is particularly evident in the classic soil-plant-atmosphere continuum (SPAC), which describes a unidirectional water flow from soil to atmosphere. However, increasing evidence highlights reverse fluxes, such as the downward movement of water from the atmosphere to plants and potentially into the soil. One key mechanism enabling this is foliar water uptake (FWU), through which leaves directly absorb moisture from sources like fog, facilitating rapid hydration and internal redistribution of water. Despite growing documentation in eco-physiological research, FWU remains largely absent from broader scientific discourse, public policy, education, and ecosystem management frameworks. Neglecting FWU and fog as hydrological inputs limits our understanding of water dynamics in ecosystems, especially under climate change scenarios that alter fog and dew formation patterns. This viewpoint emphasizes the urgency of integrating FWU into ecological models, science education, and environmental decision-making. By rethinking the water cycle through this lens, we highlight a transformative pathway to enhance conservation strategies, understanding plant functional traits related to climate change, and the science-policy-society interface.

Abstract in English:

Abstract The flora of the Cerrado is highly adaptable to climatic and edaphic variability, yet climate change and anthropogenic activities pose increasing challenges. Water is a vital resource for plant physiological and reproductive processes, and directly influences floral traits and pollinator visitation. Moreover, plant responses to fluctuations in water availability can similarly affect their ability to attract pollinators by altering floral attractants. The production and maintenance of flowers require considerable energetic investment, in addition to supporting critical physiological functions. This study assessed the water potential of Palicourea rigida inflorescences across different Cerrado phytophysiognomies and times of day, relating it to the frequency of floral visitors. The results revealed that water potential varied with environment and time and was positively correlated with visitation frequency, explaining up to 19.3 % of the variation in the number of floral visitors. These findings highlight the importance of water potential as a functional trait, especially in the context of increasing drought, with implications for reproductive success and the conservation of savanna flora. This factor should be taken into account in studies addressing functional traits in savanna ecosystems.