Harm or Benefit? Ecological Role of Merobruchus paquetae Beetles in the Germination of Libidibia ferrea Seeds

Abstract

The study of insect-plant interactions is essential for understanding seed dispersal and predation, key processes shaping plant population dynamics and reproductive success. This study examines the interaction between Merobruchus paquetae and Libidibia ferrea seeds, focusing on the beetle's life cycle and its impact on germination. Biometric parameters (length, thickness, and weight) of perforated and non-perforated seeds were measured, and the beetles’ life cycle was monitored. The germination experiment involved 160 seeds distributed across four treatments: T1 = perforated near the embryo; T2 = perforated opposite the embryo; T3 = control (non-perforated); and T4 = non-perforated with mechanical scarification, each with four replicates of 10 seeds. The beetle’s life cycle is associated with seeds, from oviposition in the fruit pericarp to larval consumption of the cotyledons, thereby compromising seed viability. Analysis indicated that 62% of seed perforations did not damage the embryo. Infested seeds were ~19% lighter than healthy ones and tended to be longer. Germination tests showed that beetle-perforated seeds failed to germinate, whereas mechanical scarification overcame physical dormancy and increased both germination percentage and speed. These findings indicate that beetle damage extends beyond seed coat rupture, reducing seed viability. Despite this negative effect, the beetle appears to prefer larger seeds and perforate regions opposite the embryo, leaving some seeds intact. This suggests that partial seed loss may not compromise plant survival, although further investigation is needed. Understanding this interaction highlights seed predation as a selective factor in the evolution of plant reproductive strategies and supports species management and conservation.

Keywords:
Seed coat dormancy; Ecological interactions; Survival.

HIGHLIGHTS

• Infestations begin in fruits on the mother plant, with larvae directed to the side opposite the embryo.

• Beetles perforate seeds, compromising their viability, but facilitate moisture entry into the indehiscent pod.

• Infested seeds were longer but 19% lighter than non-perforated seeds.

• Mechanical scarification increases both seed germination percentage and speed.

INTRODUCTION

The study of ecological interactions between insects and plants is essential for understanding the processes that shape biodiversity in diverse ecosystems. Among these interactions, pollination, seed predation, and seed dispersal stand out as key processes for the maintenance of plant communities [¹,²]. A relevant interaction occurs between beetles of the subfamily Bruchinae and leguminous plants, characterized by specific adaptations for using seeds as food and reproductive resources. These insects may act as potential pests [³,⁴,⁵] or, depending on the plant species, promote seed germination [⁶]. Such interactions influence both the population dynamics of the species involved and the ecological processes of forest regeneration.

Libidibia ferrea (Mart. ex Tul.) L.P.Queiroz, commonly known as pau-ferro or jucá, is endemic to semiarid regions of Brazil, such as the Caatinga, and to dry inselbergs in the Atlantic Forest [⁷,⁸]. In addition to its ecological role, it has economic and medicinal value, being traditionally used in the treatment of various ailments due to its antimicrobial, antioxidant, and anti-inflammatory properties [⁹].

Recent studies indicate that L. ferrea seeds exhibit seed coat (physical) dormancy, a mechanism that directly affects germination time and seedling establishment in both natural and managed environments [¹⁰,¹¹]. The resistant seed coat protects against predation and extreme environmental conditions [¹²], allowing seeds to remain viable in the soil for extended periods while awaiting favorable climatic conditions for germination [¹³,¹⁴]. However, seeds of this species often face pest-related challenges, such as attacks by beetles of the subfamily Bruchinae, throughout their geographic range [¹⁵]. These ecological aspects remain insufficiently documented and understood, particularly regarding whether this interaction represents a mutualistic relationship, where seed coat disruption benefits both beetle development and plant germination, or an antagonistic one, in which L. ferrea is harmed due to seed viability loss. This issue becomes relevant considering that Libidibia ferrea produces indehiscent fruits, whose seeds can remain stored inside the fruits for long periods, even after dispersal, and, when scarified, exhibit higher germination rates and normal seedling development [¹⁶].

All this knowledge about processes related to seed biology has direct implications for restoration programs and seed production systems and, in an increasingly demanding industry, highlights the need for healthy seeds to ensure high productivity. Accordingly, technological solutions and practical approaches, such as seed management protocols (post-harvest practices), are essential for the development of standard operating procedures (SOPs) in community nurseries [¹⁷]. These protocols support ecological restoration and the sustainable use of species for urban and rural reforestation, with associated benefits to human health and well-being. They involve controlling biological and non-biological factors affecting seeds, proper storage, and quality testing to improve germination performance and reduce losses [¹⁷].

Within this context, the present study investigates the interaction between the beetle Merobruchus paquetae and the seeds of L. ferrea, focusing on the insect’s life cycle and its ecological implications, particularly regarding seed germination. More broadly, this research aims to contribute to the understanding of plant-insect interactions, assessing whether M. paquetae acts as a pest or a facilitator of seed germination in semiarid ecosystems, based on ecological theories emphasizing coevolutionary and adaptive relationships between species. The results are expected to support the development of management and conservation strategies for L. ferrea, a species of ecological and socioeconomic importance in northeastern Brazil, especially in degraded areas where its natural regeneration plays a key role in biodiversity recovery and ecosystem restoration.

MATERIAL AND METHODS

Studied species

Libidibia ferrea (Mart. ex Tul.) L.P. Queiroz, a large tree of the family Fabaceae, is endemic to northeastern Brazil and stands out for its ecological importance, particularly as a food source for various local fauna species [⁸]. This leguminous plant produces indehiscent fruits containing large seeds with high protein and lipid content, which attract a variety of herbivores, including insects of the family Bruchidae [¹⁵,¹⁶]. The interaction between the plant and its herbivores is crucial for the species’ natural regeneration dynamics, as seed predation can significantly reduce germination rates [¹⁸].

The beetle Merobruchus Bridwell (Coleoptera: Chrysomelidae: Bruchinae) is recognized as a seed pest of several legume species, including L. ferrea [¹⁵]. During its life cycle, adults oviposit on mature seeds, and the larvae develop inside the seeds, consuming the cotyledons and ultimately compromising seed viability [¹⁹,⁴]. Previous studies have reported that Merobruchus sp. larvae can reduce seed germination rates of affected legumes by up to 70% [²⁰,²¹].

Taxonomic identification of the specimens was conducted through comparative morphological analysis using stereomicroscopy, focusing on external diagnostic characters and following the dichotomous key for American species of the genus Merobruchus Bridwell. Identification was based on congruence with the diagnostic characters of Merobruchus paquetae (Viana, 1964), as described and illustrated in specialized literature [⁴]. The main characters evaluated included the presence of gibbosities at the base of elytral striae 3 and 4, the pattern and distribution of mottled pubescence on the elytra and pronotum, the morphology of the hind femur, and the shape of the pygidium and the last abdominal ventrite. These characters were compared directly with published descriptions and figures [⁴]. Additionally, the identification is supported by host association, as M. paquetae has been recorded infesting seeds of Fabaceae belonging to the subfamilies Mimosoideae and Caesalpinioideae, including species of the tribes Ingeae, Mimoseae, and Caesalpinieae [⁴].

Life cycle of the beetle M. paquetae and seed germination of pau-ferro

Fully mature fruits were collected from Libidibia ferrea (commonly known as “pau-ferro”) trees shortly after natural dispersal in protected areas, zoobotanical parks, and public squares in Teresina (PI), Brazil, between September and December 2023. Fruits were sampled from multiple trees across the study area and included both fruits fallen on the ground and mature fruits still attached to the trees, identified by their brownish coloration.

In the laboratory, fruits were manually opened and seeds were individually examined. Seeds constituted the experimental unit for all subsequent analyses, including beetle infestation, seed morphometry, perforation patterns, and germination. The impact of beetle infestation on seed germination was assessed at the seed level by recording infestation status (infested vs. non-infested or perforated and non-perforated), the position of the perforation relative to the embryonic axis, and germination responses under controlled laboratory conditions of temperature and humidity, as described below.

To describe the life cycle of the beetle Merobruchus paquetae (Viana, 1964), (Coleoptera: Chrysomelidae: Bruchinae) under controlled laboratory and quarantine conditions, 100 mature fruits were intentionally infested and monitored daily through video recording and direct observations. Additionally, seeds were manually extracted from the indehiscent fruits using a hammer and subsequently homogenized. Initially, a group of 110 perforated seeds (post-emergence of the beetle) was analyzed to record the position of the perforation in relation to the embryo, classifying them as perforated either adjacent to or opposite the embryo. Subsequently, another set of 50 perforated and 50 non-perforated seeds were separated for morphometric analysis, including measurements of weight, length, and thickness, using a digital caliper and an analytical precision balance. Paired measurements of seed mass before and after infestation were not performed due to the absence of effective direct infestation under controlled conditions, as the beetles died before oviposition, which limited the quantification of biomass loss and reserve consumption to an average estimate based on the difference between perforated and non-perforated seeds.

To evaluate the effect of beetle infestation on seed germination, a completely randomized experiment was conducted using 160 seeds, distributed into four treatments with 40 seeds each, arranged in four replicates of 10 seeds per treatment. All seeds were obtained from fruits stored under standardized refrigeration conditions prior to the experiment in order to prevent additional infestations. Seeds were individually inspected for evidence of initial infestation, and any seed showing signs of pre-existing larval infestation was excluded from the sample. Seeds classified as perforated corresponded exclusively to seeds from which adult beetles had already completely emerged.

The treatments were as follows: T1 = seeds perforated adjacent to the embryo; T2 = seeds perforated opposite the embryo; T3 = non-perforated seeds (control); and T4 = non-perforated seeds subjected to mechanical scarification opposite the embryo. Mechanical scarification was performed manually using waterproof sandpaper (grit 80) applied to the seed coat for 10 seconds, with care taken to avoid damage to the cotyledons and embryonic axis. Scarified seeds were visually inspected to confirm uniform abrasion of the seed coat without tissue exposure, ensuring quality control and consistency across samples.

Selected seeds were disinfected with a 3% sodium hypochlorite solution and germinated in a B.O.D. chamber at 25 °C under a 12-hour photoperiod. The experiment lasted 30 days, with germination recorded every three days. Germination Percentage (GP), Mean Germination Time (MGT), and Germination Speed Index (GSI) were calculated according to [²²].

Data analysis

Differences among germination treatments and morphometric variations of the seeds were analyzed using analysis of variance (ANOVA). Prior to the analyses, the assumptions of normality and homoscedasticity were evaluated through residual analysis, including the Shapiro-Wilk test for normality and Levene’s test for homogeneity of variances. Mean values were compared using Tukey’s honestly significant difference (HSD) test at a 5% significance level. All statistical analyses were performed using STATISTICA software.

RESULTS

The beetle's life cycle begins with the female's oviposition behavior. She lays her eggs on the surface of the pericarp of fruits at the final stage of maturation on the mother plant, usually near the locules where the seeds are located (Figure 1A). This behavior follows a specific oviposition pattern that determines the route of the subsequent larvae. After hatching, the larvae emerge and migrate through a small perforation toward the seeds (Figure 1B, C), where they settle to feed on the nutritional content, especially the cotyledons (Figure 1D). Once their development inside the seeds is complete, the mature larvae emerge as adults by perforating the seed coat and then the fruit pericarp to exit. This process marks the end of the larval stage and the beginning of the reproductive adult phase (Figure 1D, E). The emerged adults seek new host fruits for oviposition, thus restarting their life cycle.

Figure 1
Life cycle of the beetle Merobruchus paquetae (Viana, 1964) in fruits of Libidibia ferrea (Mart. ex Tul.) L.P. Queiroz: (A) oviposition on the fruit pericarp near the seed locules; (B) arrow indicating larval perforation upon egg hatching; (C) larval perforation of the seeds; (D) beetle emergence from the seeds; (E) insect perforating the fruit pericarp to exit; (F) lateral view of the male (left) and female (right), and dorsal view.

We observed that 62% of the seeds were perforated on the side opposite to the embryo, without compromising seed development. In contrast, approximately 38% showed perforations near the embryo, resulting in damage caused by the larva. It is also noteworthy that, on average, at least half of the seeds per pod remained intact, showing no signs of perforation.

We observed significant differences in weight and length between perforated and non-perforated seeds. Perforated seeds were longer but 19% lighter than non-perforated ones. Seed thickness was similar between the two groups (Figure 2).

Figure 2
Biometric variations (weight, length, and thickness) of perforated and non-perforated seeds of Libidibia ferrea (Mart. ex Tul.) L.P. Queiroz by the beetle Merobruchus paquetae (Viana, 1964) Lowercase letters denote significant differences between perforated and non-perforated seeds (F-test; p < 0.05).

We found no germination in perforated seeds, regardless of the perforation’s position relative to the embryo (T1 and T2). However, during the germination experiment, perforated seeds showed rapid size increase in the initial imbibition phase, indicating significant water uptake within minutes, whereas some non-perforated seeds maintained their original shape. Germination occurred in control seeds (T3; without perforation) at a rate of 20%, and was significantly higher in mechanically scarified seeds (100%) (Figure 3). Although germination occurred in the control treatment, it was slower and delayed (MGT = 15.95; GI = 0.12) compared to mechanically scarified seeds, which showed shorter germination time and higher velocity (MGT = 1.37; GI = 0.12).

Figure 3
Germination Percentage (GP), Mean Germination Time (MGT), and Germination Speed Index (GSI) of Libidibia ferrea (Mart. ex Tul.) L.P. Queiroz seeds under treatments with presence/absence of perforation by the beetle Merobruchus paquetae (Viana, 1964). T1 = seeds perforated adjacent to the embryo; T2 = seeds perforated opposite the embryo; T3 = non-perforated seeds (control); T4 = mechanically scarified seeds with sandpaper. Lowercase letters denote significant differences among treatments (Tukey’s test; p < 0.05).

DISCUSSION

Merobruchus Bridwell (Coleoptera: Chrysomelidae: Bruchinae) is a genus known for its life cycle associated with specific host plants, feeding specifically on seeds of Mimosoideae (Acacieae, Ingeae, and Mimoseae) [⁴]. In this study, under controlled conditions, the beetle’s life cycle shows a specific oviposition pattern on fruits still maturing on the mother plant, directing larvae to the locules, where they lodge in the seeds and feed on the nutritional content. Our findings revealed a distinct pattern of seed perforation by M. paquetae larvae, in which approximately 62% of the seeds are perforated in a manner that does not affect the developing embryo (i.e., on the side opposite to the embryo). We further suggest that this perforation pattern is likely to be repeated under field conditions.

Differences in weight and length were observed between perforated and non-perforated seeds. Interestingly, perforated seeds had greater length, suggesting a preference by beetles for larger seeds for infestation. Differences in seed weight were influenced by perforation. This pattern may indicate that the production of larger seeds, despite its higher energetic cost, may represent a beneficial trait for plant survival by potentially concentrating larval attack in specific locules, thereby preserving part of the seed production. This possible hypothesis of producing groups of seeds with different characteristics is a reproductive strategy already documented in plant species [²³], helping increase the chances that at least some seeds remain intact, reach the soil, and complete the germination process.

We observed that, on average, perforated seeds had 19% less mass than non-perforated ones, indicating that the beetle tends to consume only a small fraction of the total seed weight. However, weighing was not performed before infestation, so this hypothesis is based on the mass difference between infested and non-infested seeds. According to [¹⁵], beetles consume about 37% of the original seed weight, a much higher percentage than the average observed here, reinforcing the idea that biomass loss of cotyledons impacts seed viability. Normally, during seed maturation inside indehiscent fruits, there is a significant decrease in weight and size of structures, where water content slowly and continuously decreases to values of up to 50% [¹⁶] or even lower percentages, as observed in orthodox seeds. We believe that this described variation may also influence the initial choice of beetles, directing them preferentially toward seeds at earlier stages of maturation, that is, larger seeds, which should be further investigated in the studied species.

The oviposition site choice by M. paquetae beetles is closely related to the physical characteristics of host seeds, selecting seeds that favor larval survival, such as seed coat consistency and the amount of cotyledons available for consumption in legumes [⁴,²⁰]. Therefore, greater nutritional reserves in seeds may be proportional to higher infestation rates. Larger seeds with higher nutrient content, such as lipids and proteins, are more attractive to insects and provide better support for larval development [²⁴]. These traits result from fruit predation, which acts as a selective pressure and may induce plants to adopt distraction or prevention strategies, such as producing inviable seeds, however, specialized predators can overcome these defenses [²³].

Specifically, L. ferrea seeds have an oval shape and a rigid seed coat or tegument [²⁵], which may directly influence beetle preference. The beetles’ choice for seeds with thicker and tougher coats acts as a natural barrier against predators while also potentially favoring beetle larvae during their early developmental stage by providing protection and a safer environment for growth [²⁰]. On the other hand, smaller seeds or those with thinner coats tend to be less attractive and consequently less infested, as they offer limited resources for larval development and germination potential for the plant [²⁶,²⁷]. This seed differentiation effect may relate to variation in seed size and hardness, causing some to be more vulnerable to attack while others remain intact. Thus, physical resistance and seed content should be considered primary defense factors, as they directly influence infestation rates and may contribute to the species’ survival strategy [¹²]. These trends reflect the adaptive strategies of each species to cope with pest pressure.

We observed that perforated seeds did not germinate, despite absorbing water rapidly. Only the non-perforated seeds germinated, with a higher percentage and faster speed in scarified seeds (100%) compared to the control (20%). This suggests that scarification overcomes physical dormancy, while predation prevents germination by compromising the embryo. This result indicates that the interaction between the beetle and the plant is predominantly negative with respect to germination, as infestation directly compromises seed viability. Consequently, predation by this beetle species may act as a limiting factor for natural regeneration, influencing the population dynamics of the plant species under study. However, in some legumes, seed predation may also promote germination, a phenomenon rarely documented [⁶] and not observed in this study. In light of this, future studies should experimentally integrate the effects of seed coat rupture and reserve loss caused by predation, a limitation of the present study, by more precisely investigating the pattern and threshold of seed perforation at which germination is inhibited or potentially facilitated.

Physical dormancy in the species’ seeds is characterized by the presence of a physical barrier, the seed coat, which prevents the entry of water and gases essential for the initiation of germination [²⁵]. According to [¹¹], physical dormancy occurs when the seed covering, the outer layer of the testa or seed coat, is impermeable to water. This barrier can be composed of densely compacted cells or waxy coatings, hindering internal hydration even under suitable environmental conditions. In the case of pau-ferro seeds, scarification, by physically breaking the seed coat, facilitates water uptake, a determining factor for overcoming dormancy and promoting germination in this species [¹⁰].

Physical dormancy in L. ferrea seeds can be overcome by natural processes, such as the action of physical agents (heavy rains, wind abrasion, or wear caused by animals), or mechanical means, such as artificial scarification, widely used in studies to promote germination [²⁸]. This dormancy mechanism is an adaptation that protects the seed against adverse environmental conditions, ensuring that germination occurs only when environmental conditions are ideal, such as sufficient water availability for hydration and embryonic development (11).

Additionally, we observed that some pau-ferro seeds germinated without scarification, suggesting the presence of intermittent physical dormancy. This type of dormancy occurs when the physical barrier of the seed coat is not completely impermeable, allowing, under certain conditions, the entry of water and gases. However, most seeds still depend on some type of scarification to overcome these limitations [¹⁰] and increase germination speed. This irregular germination behavior may be influenced by environmental factors, such as moisture variations, or biological factors, such as agents that promote natural scarification of the seed coat, facilitating germination under favorable conditions [⁹]. This trait may also be associated with different maternal plant growth conditions, resulting in varied dormancy phenotypes even within the same genotype. These phenomena are modulated by genetic and epigenetic factors that regulate secondary dormancy, influencing phytohormone signaling and gene expression, with variations in dormancy depth among lineages [²⁹,³⁰].

Although the beetle is capable of promoting seed coat scarification, feeding on seed reserves (cotyledons) compromises their physiological quality and germination, even without affecting the embryo structure in most cases, possibly due to a preference for perforation in opposite regions. The cotyledons’ role, partially consumed during feeding, is important in sensing environmental signals and is fundamental to the dormancy cycle, as they possess specific mechanisms regulating germination and environmental signal perception, including hormonal pathways associated with abscisic acid (ABA), a phytohormone essential for seed dormancy control, mediated by gene expression [²⁹].

These results, obtained under controlled conditions, highlight the complexity of the interaction between the beetle and Libidibia ferrea seeds, which likely reflects the dynamics occurring under natural field conditions. Although predation negatively affects germination, this pressure does not appear sufficient to eliminate the studied legume population from its natural environment, since not all seeds are attacked or perforated. The persistence of intact seeds may contribute to annual population renewal, a possibility that deserves further investigation. The evolutionary history of interactions between seed beetles (Bruchinae) and native legumes suggests that predation pressure has likely acted as an important selective force, favoring plant traits that reduce the negative effects of infestation [⁴]. This pattern is widely documented as a coadaptive relationship, in which legumes evolve defense strategies such as high seed production, variation in seed size, and hard seed coats, while beetles adjust their life cycles and reproductive strategies to maximize exploitation of these resources, contributing to a dynamic ecological balance [³¹].

Another strategy observed in Fabaceae, including the species studied here, is mast seeding, characterized by years of high seed production alternating with periods of low or no fruiting. This mechanism hampers the maintenance of predator populations by reducing the regular availability of seeds as a resource. According to [³³], this unpredictability not only regulates predator populations but also reduces predation pressure in subsequent years. Furthermore, plants like Senna multijuga demonstrate that producing many small seeds can satiate predators and ensure that some seeds remain available for germination [³⁴].

Therefore, the proper management of L. ferrea seeds involves careful screening to exclude seeds with larval entry perforations or beetle exit holes, refrigerated storage to prevent new infestations, and standardized mechanical scarification to increase germination rates. These practices support the development of standard operating procedures (SOPs) for community nurseries and, by improving the species’ germination performance [¹⁷], strengthen ecological restoration efforts in its natural areas of occurrence, such as inselbergs in the Caatinga and Atlantic Forest, while also supporting seedling production for urban and rural use. However, the need for and intensity of interventions aimed at eliminating the beetle should be carefully evaluated, considering the proportion of seeds effectively lost relative to total production and seedling establishment, as encouraged in future studies. In natural environments, the population dynamics of the beetle are expected to be regulated by ecological mechanisms, including natural biological control, which reinforces that its presence is part of ecosystem functioning [³⁵,⁶] and should not be interpreted as a justification for its exclusion.

CONCLUSION

The life cycle of Merobruchus paquetae demonstrates a close association with Libidibia ferrea, from oviposition in green pods to development within mature seeds. Based on the results obtained, this interaction should be interpreted as predominantly negative, since perforated seeds did not germinate, whereas mechanically scarified seeds showed high germination, indicating that insect damage compromises seed viability, mainly through the reduction of energy reserves. Although seed coat perforation may, in principle, facilitate water entry, the data do not support a germination benefit. It is important to highlight that not all seeds are preyed upon within the pods and that perforations in regions opposite the embryo do not appear to occur randomly, suggesting possible selective processes in the insect-plant interaction, potentially related to insect satiation and the maintenance of plant species persistence, which deserves monitoring over consecutive years to follow the progression of this interaction. Furthermore, our experimental design does not allow us to understand the extent to which the degree of predation represents a threshold between benefit and harm, and we suggest that future studies simulate gradual and artificial reductions of cotyledons to assess the extent to which this loss does not affect germination. Finally, it is emphasized that the need for and intensity of interventions to regulate beetle populations in native environments should be carefully evaluated, considering the proportion of seeds effectively lost relative to total production, as well as the potential role of natural regulatory mechanisms, so as not to compromise ecological interaction networks or generate environmental impacts.

• Funding:
  This research did not receive external funding and was supported solely by the advisor’s research grant (process no. 167901/2022-2) from the National Council for Scientific and Technological Development (CNPq).
• Institutional Review Board Statement:
  Not applicable. This study did not involve humans or vertebrate animals, only insects and plants.
• Informed Consent Statement:
  Not applicable.

Acknowledgments:

The Federal University of Piauí is gratefully acknowledged for logistical support and providing the infrastructure necessary for conducting this research. We also thank the National Council for Scientific and Technological Development (CNPq) for funding the scholarship.

Use of Generative Artificial Intelligence

The authors declare that large language models and other generative artificial intelligence (AI) or AI-assisted technologies cannot be credited as authors and have not been listed as authors of this paper.

The authors declare that generative artificial intelligence (AI) or AI-assisted tools were used under full human supervision. The tool(s) used were ChatGPT (OpenAI) for language translation and minor grammatical revision only. No AI tools were used for study conception, data collection, data analysis, interpretation of results, or generation of scientific content. No confidential or sensitive data were uploaded to such tool(s), and all AI-assisted content was checked, corrected and approved by the authors, who take full responsibility for the integrity and originality of the manuscript.

Data Availability Statement:

The data used in this study are available upon request from the corresponding author.

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• Editor-in-Chief:
  Bill Jorge Costa

• Associate Editor:
  Paulo Vitor Farago

Publication Dates

• Publication in this collection
  31 July 2026
• Date of issue
  2026

History

• Received
  16 Jan 2026
• Accepted
  19 May 2026