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Filogeografia e taxonomia de Goyazana castelnaui (H. Milne-Edwards, 1854) (Decapoda: Trichodactylidae) nas bacias dos rios Parnaíba, São Francisco e Tocantins-Araguaia

2026-06-01T16:06:21Z

Título: Filogeografia e taxonomia de Goyazana castelnaui (H. Milne-Edwards, 1854) (Decapoda: Trichodactylidae) nas bacias dos rios Parnaíba, São Francisco e Tocantins-Araguaia Autor(es): Freita, Francisco Ronaldo Vieira Abstract: The freshwater crab Goyazana castelnaui (H. Milne-Edwards, 1854) has a wide geographic distribution, which may result in significant variability within the species. The objective of this study was to analyze intraspecific variability among populations of G. castelnaui using molecular and morphological tools in the São Francisco, Parnaíba, and Tocantins-Araguaia River basins. Specimens from natural populations were captured manually in the marginal waters of rivers and dams. They were then taken to the LACRUSE laboratory, where they were identified and cataloged. In addition, sequences deposited in the GenBank database from a specimen from the Tocantins/Araguaia basin, as well as from other species of the family Trichodactylidae and the external group, were obtained to support the phylogenetic tree. After identification, the animals were measured, and then the left gonopod of each specimen was removed for morphological analysis. A sample of muscle tissue was also obtained and used for mitochondrial DNA extraction, using the phenol-chloroform method. After DNA extraction, a phylogenetic analysis was performed based on the two mitochondrial genes (16S rRNA and COI). As for the morphological comparison of the gonopods, the data were analyzed using a scanning electron microscope (SEM) and a stereomicroscope. The results demonstrated the existence of phylogenetic divergence in the genes, confirming the presence of three lineages, whereas the morphological analysis of the gonopods revealed a difference between the populations of G. castelnaui from the São Francisco and Parnaíba River basins. These differences suggest that the populations in these basins represent distinct lineages. However, the phylogenetic analysis included all three basins, while the morphological analysis was applied only to the São Francisco and Parnaíba basins. Tipo: Tese

Sinopse da família Melastomataceae Juss. para o estado do Ceará

2026-05-29T03:37:54Z

Título: Sinopse da família Melastomataceae Juss. para o estado do Ceará Autor(es): Mota, Carlos Adrian Rodrigues Abstract: Melastomataceae is a monophyletic family comprising 173 genera and approximately 5,850 species, of which 1,523 occur in Brazil and 1,008 are endemic. This study aims to assess the actual species richness and distribution of Melastomataceae in the state of Ceará, based on data obtained from biological collections and field expeditions, through the analysis of herbarium specimens, illustrations, photographs, and type material. A total of 50 species and 14 genera were recorded, including nine new species records and three new genus occurrences for the state. Furthermore, field expeditions enabled the recollection of Aciotis annua in Ceará after more than 180 years without records. This study provides taxonomic comments, identification keys, photographic plates of plants in the field, and maps of geographic distribution. Tipo: Dissertação

Interações de micropartículas de TiO2 com os sistemas biológicos Lactuca sativa L., Artemia salina e Danio rerio

2026-05-28T14:40:46Z

Título: Interações de micropartículas de TiO2 com os sistemas biológicos Lactuca sativa L., Artemia salina e Danio rerio Autor(es): Lima, Ana Kamila Medeiros Abstract: Nanostructured materials have revolutionized modern life. Numerous compounds have undergone size reduction processes and have been reintroduced into sectors such as health, cosmetics, food, agriculture, technology, and others. The compound used in this work is titanium dioxide microparticles (TiO2MPs). It is a metal produced on a large scale and used in sunscreen formulations, in food as a colorant, in aquatic depollution strategies, among others. The objective of this work was to characterize the effects of titanium dioxide toxicity on biological systems. The three models chosen were: Lactuca sativa L., Artemia salina, and Danio rerio. Experiments were carried out exposing the models to different concentrations: lettuce to 50 mg.L-1 TiO2MPs, artemia to 12.5, 25, 50, and 100 mg.L-1 TiO2MPs, and zebrafish to 1, 10, and 100 mg.L-1 TiO2MPs. The results were analyzed using conventional optical microscopy, scanning electron microscopy, and transmission electron microscopy. Anatomical and ultrastructural damage confirmed the compound's toxicity to lettuce. In artemia, it caused a high mortality rate in addition to cellular damage at concentrations of 25, 50, and 100 mg.L-1 TiO2MPs. In zebrafish, however, there was no mortality or high rate of deformation. TiO2MPs showed toxicity dependent on concentration, time, and biological model. Even without confirmed absorption, direct contact causes cellular and structural damage in plants and animals. The results highlight the importance of chronic studies under realistic environmental conditions to assess the impact of TiO2MPs on ecosystems and food chains. Tipo: Tese

Microbioma associado à Mimosa tenuiflora (Willd.) Poir. em área suscetível à desertificação da caatinga e o potencial funcional de bactérias endofíticas para a recuperação de áreas degradadas

2026-05-19T12:15:44Z

Título: Microbioma associado à Mimosa tenuiflora (Willd.) Poir. em área suscetível à desertificação da caatinga e o potencial funcional de bactérias endofíticas para a recuperação de áreas degradadas Autor(es): Rocha, Jeanderson da Silva Abstract: Desertification in the Brazilian semiarid region poses a growing threat to Caatinga biodiversity and ecosystem services. Mimosa tenuiflora (Willd.) Poir. (jurema-preta) stands out as a dominant pioneer species in degraded areas and for its contribution to natural regeneration; however, the microbiological mechanisms underlying its resilience remain poorly understood. This study aimed to characterize the bacterial microbiome associated with the rhizosphere and root endosphere of M. tenuiflora in an area susceptible to desertification and evaluate the effect of endophytic bacterial inoculation on seedling early development. To this end, the root bacterial microbiome of M. tenuiflora was characterized for the first time in the municipality of Irauçuba, Ceará state, through amplicon sequencing of the 16S rRNA gene V4 region. Libraries were normalized by rarefaction (60,000 reads/sample) and analyzed for alpha diversity, beta diversity, and taxonomic composition. The rhizosphere exhibited significantly higher alpha diversity than the endosphere, a pattern consistent with progressive host-mediated filtering. Beta diversity analysis revealed significant compositional differentiation between compartments (PERMANOVA: R² = 0.536, p = 0.009), with greater rhizospheric homogeneity and endospheric heterogeneity. At the phylum level, Pseudomonadota dominated the endosphere, while Actinomycetota was more abundant in the rhizosphere. Differential abundance analysis identified 11 significantly enriched genera (p-adj < 0.05, |log2FC| ≥ 2): 10 in the rhizosphere (Conexibacter, Neobacillus, Crossiella, among others) and one in the endosphere (Rhizobium). The endosphere was dominated by the Burkholderia-Caballeronia-Paraburkholderia complex, known for symbiotic nitrogen fixation and multiple plant growth-promoting capabilities, followed by Klebsiella and Mycobacterium. The results reveal functional partitioning between compartments, with endospheric specialization in nutrient provisioning and stress mitigation versus maintenance of rhizospheric diversity related to decomposition and nutrient cycling. In vitro inoculation experiments with M. tenuiflora seedlings demonstrated that the Serratia rubidaea + Citricoccus sp. endophytic consortium promoted increased root growth compared to the control (p.adj < 0.05), confirming the potential of native strains to promote plant growth. This structuring constitutes an adaptive strategy to desertification conditions, explaining the resilience of M. tenuiflora in degraded soils and providing the basis for bioinoculant development and Caatinga ecological restoration strategies. Tipo: Dissertação