https://repositorio.ufra.edu.br/jspui/handle/123456789/16 Biblioteca Digital de Teses e Dissertações. 2026-08-22T16:51:04Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2896 Título: Zooplâncton Gelatinoso no Atlântico Tropical Oeste: distribuição, estrutura populacional e ênfase em Pyrosoma Autor(es): OLIVEIRA, Ludmilla Karina Lima Abstract: Planktonic tunicates of the genus Pyrosoma are part of the gelatinous zooplankton and play a relevant role in the transfer of energy and matter in the ocean, yet they remain underestimated and understudied in the Tropical Atlantic, partly due to their fragility and the limitations of traditional sampling methods. Hydromedusae, another component of the gelatinous zooplankton, shared this history of scientific neglect, with taxonomic records still scarce for the Brazilian equatorial margin. This dissertation investigated, in two complementary chapters, the distribution and ecology of these groups in the Western Tropical Atlantic. Chapter II analyzed the spatial (horizontal and vertical) and temporal (day–night) structure of the genus Pyrosoma in the North and Northeast regions of Brazil, characterizing the physical and chemical variables of the water column (temperature, salinity, dissolved oxygen, turbidity, and fluorescence) and correlating them with colony density (CPUE; colonies·hour⁻¹) and size structure (length in mm). Data were obtained from three oceanographic surveys conducted aboard the R/V Antea , ABRAÇOS I (2015), ABRAÇOS II (2017), and AMAZOMIX (2021), using diurnal and nocturnal oblique trawls with a mesopelagic micronekton net. Analyses included comparisons among regions, depth layers, and time periods (Kruskal–Wallis, Wilcoxon), Spearman correlation, distance-based Redundancy Analysis (db-RDA), and Generalized Linear Models with a Gamma distribution. Chapter III reported the first records of the hydromedusae Leuckartiara octona and Calycopsis papillata (Hydrozoa: Filifera) for the Brazilian Equatorial Margin, based on samples collected during the AMAZOMIX survey. Morphological descriptions of the specimens, density data, vertical distribution, and the environmental conditions associated with the occurrence of each species in relation to the Amazon River plume were presented. Together, both chapters contributed to expanding the knowledge of gelatinous zooplankton diversity and ecology in the Western Tropical Atlantic, highlighting how regional physical-oceanographic gradients, particularly the contrast between the Amazon plume and the oceanic conditions of Northeast Brazil, modulate the distribution, abundance, and population structure of the studied groups. 2026-01-01T00:00:00Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2895 Título: Desvendando o comércio de peixes no nordeste paraense. Autor(es): FARIAS, Tiago Sousa de Abstract: The Brazilian Amazon Coast (LAB) has a high biodiversity of aquatic organisms, especially fish. Local fishing activity has an impact on aquatic resources, whether they are targeted by fishing methods (accompanying fauna), and is a global threat to species, especially those threatened with extinction, such as sharks and rays. Even though fish are a nutritionally, economically, and culturally important resource for the Brazilian Amazon, there is a recurring lack of data on the catch and composition of the species sold. Especially in cases where a) more than one species is sold under a single popular name; b) the fish species have high morphological similarity; c) the fish have low commercial value; and d) the fish are sold uncharacterized (without heads, fins, etc.) in the markets, which creates difficulties in identifying and measuring them. The research problem lies in the lack of data on the dynamics of fish marketing in the fish markets of Bragança, Capanema, Castanhal, Salinópolis, and São João de Pirabas. Due to the recurring lack of data on these bycatches, a scientometric survey carried out on the Scopus, Scielo, Web of Science and Google Scholar databases on the shark and ray bycatch fauna resulted in 28 scientific articles published in 21 joumals. We list 28 species of sharks and 14 species of rays cited as being caught in these articles. Of the 40 fish retailers interviewed, the majority were aged between 51 and 60 (32.5%) and between 31 and 40 (22.5%). It can be seen that the fish retail outlets are supplied by middlemen or directly by fishermen firom various fishing locations. For both the dry and rainy seasons, 17 fish were cited as the most frequent. Among the 32 most frequent fish throughout the year, "Gó" (22.4%) and "Bandeirado" (9.2%) were the most frequent. The presence of 43 species of commercialized bony fish was recorded, of which only three species were identified to genus levei due to their high morphological similarity. On the other hand, cartilaginous fish were identified at a specific levei in only two species due to the way they are sold, such as carcasses or types of cut, which makes it difficult to diagnose the species. We also identified two cases of homonymy, one of synonymy, and 12 totally local commercial names. We noticed a predominance of coastal fish sold in coastal towns (71%) and non-coastal towns (66.6%), but an increase in freshwater fish in non-coastal towns due to their case of logistics. 2025-07-15T00:00:00Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2894 Título: Caracterização, avaliação morfológica e morfoanatomia da lâmina foliar de acessos de Pilocarpus microphyllus Stapf ex WardleworthRutaceae, Ananas comosus var. erectifolius (L. B. Smith) Coppens & F. Leal-Bromeliacea e Psychotria ipecacuanha (Brotero) Stokes-Rubiaceae, conservados no banco ativo de Germoplasmа Autor(es): ANDRADE, Carlos Renato Silva Abstract: This study aimed to characterize and evaluate the morphological and morphoanatomic of Pilocarpus microphyllus hits Stapf ex-Wardleworth Rutaceae, Ananas comosus var. erectifolius (L. B. Smith) Coppens & F. Leal-Bromeliacea and Psychotria ipecacuanha (Brotero) Stokes-Rubiaceae, stored in Active Germplasm Bank of medicinal plants at Embrapa Amazônia Oriental, in Belém, PA. For both were chosen at random. 10 accessions of each species, being characterized for 3-9 qualitative characters and evaluated to 3-4 quantitative traits. For qualitative characters were obtained the occurrence percentages, while quantitative were analyzed by univariate and multivariate analyzes, the latter obtained by standardized mean Euclidean distance. The Morphology of the three species was performed by the leaf or lamina and in leaflet, and the presence of polymorphic crystals. Was diagnosed during the study, the characters can subsidize the initial drafting of a list of descriptors or morphological characters, which can be used in the characterization and evaluation. 2026-05-22T00:00:00Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2893 Título: Biologia reprodutiva do Peixe Voador Hemiodus unimaculatus na Vila Tauiry, área de influência da Usina Hidrelétrica de Tucuruí - PA Autor(es): SILVA, Maria Clara Rosa Abstract: This study compiles information on the ecological and reproductive aspects of the flying fish Hemiodus unimaculatus in the area influenced by the Tucuruí Hydroelectric Power Plant (PA, Brazil). The literature review showed that this species, a member of the family Hemiodontidae, has a wide distribution throughout the Amazon basin and exhibits remarkable trophic plasticity. Previous studies indicate that, prior to river impoundment, its diet was predominantly detritivorous and periphytic. After the formation of the reservoir, it began to display more diversified feeding habits, including omnivorous strategies. Additionally, changes in the average body size of individuals and a reduction in relative frequency in sampling surveys were observed, suggesting significant effects of damming on the local population. From a reproductive perspective, the species reaches first sexual maturation between 11 and 15 cm and exhibits an extended reproductive period from October to April, associated with the seasonality of the Amazonian flood pulse. A predominance of females has been recorded, a strategy that may maximize reproductive success but raises concerns regarding the potential reduction of genetic diversity. In Chapter 2, the histological analysis of spermatogenesis revealed testes with an anastomosed tubular pattern, typical of Characiformes, and cystic spermatogenesis characterized by synchronized development of germ cells. Four types of spermatogonia, different meiotic stages, three types of spermatids, and type III spermiogenesis were described, evidencing a continuous process of gamete production. The spermatozoa exhibited a rounded head and a long flagellum, a conformation adapted to external fertilization in aquatic environments. These findings reinforce the importance of understanding the reproductive biology and ecology of the species, providing essential support for management and conservation strategies in the face of pressures from impounded environments and hydrological modifications imposed by Amazonian dams. 2026-05-22T00:00:00Z