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Resultados da pesquisa

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  • eDNA metabarcoding reveals a rich but threatened and declining elasmobranch community in West Africa’s largest marine protected area, the Banc d’Arguin
    Publication . de la Hoz Schilling, Carolina; Jabado, Rima W.; Veríssimo, Ana; Caminiti, Luca; Sidina, Ebaye; Gandega, Cheikhna Yero; Serrao, Ester
    Elasmobranchs (sharks and rays) are the most threatened marine vertebrates, particularly in tropical and subtropical areas. Their population status is often poorly understood due to insufficient information. Despite reportedly harbouring critical elasmobranch habitats, the Banc d'Arguin National Park (PNBA) in Mauritania lacks comprehensive and updated information on the diversity of elasmobranch species in the area. We developed a baseline inventory based on morphological and molecular identification and metabarcoding. DNA barcoding of tissue samples from elasmobranch processing sites and freshly sampled specimens was used to build a genetic reference database of local elasmobranch species. The richness and diversity of species in the PNBA were described via metabarcoding of seawater eDNA samples using an elasmobranch-specific assay and our reference database. We detected 27 species, including 12 new species records for the PNBA. We further uncover potentially undescribed species of Gymnura and Torpedo, while taxonomic corrections are noted for previously reported species. In particular, the reportedly abundant Mustelus mustelus was absent from tissue and eDNA samples, while M. punctulatus was detected instead. Taxa that have anecdotally become regionally extinct or rare (e.g., sawfishes, wedgefishes, lemon sharks) were not detected, highlighting local species diversity shifts within the last few decades. Results show that 67.9% of elasmobranch species in the PNBA are threatened with extinction according to the IUCN Red List of Threatened Species. This study emphasises the importance of taxonomic identification in support of species management and provides a baseline to inform future studies and conservation measures to avoid further species losses.
  • Not regionally extinct: rediscovery of ruppia drepanensis in Portugal, the westernmost range edge in Europe
    Publication . Gonçalves Frade, Duarte; Miranda Neiva, João; Martínez-Garrido, Jose; Davison, Anne; Caminiti, Luca; Ramos, Gonçalo Miguel da Cruz e Cunha Guinote; Pearson, Gareth Anthony; Serrao, Ester A.
    Ruppia drepanensis Tineo ex Guss. is an important habitat-forming aquatic plant in saline and brackish Mediterranean wetlands. The species is declining in several parts of its range due to hydrological changes and habitat degradation. R. drepanensis was considered Critically Endangered, possibly Regionally Extinct in Portugal, due to not being observed since 1986 despite extensive surveys of suitable habitat. We report on a new population, the westernmost known record for the species in Europe, identified with morphological and molecular data. Despite being inside a protected area, this population occupies a single small pond adjacent to a road, making it vulnerable to habitat changes. Ex situ conservation is recommended, including seed banking and/or the establishment of new populations.