RT Journal Article T1 Genetic Diversity and Connectivity of Syngnathid Fish in Spanish National Parks: Conservation Insights From Protected Marine Ecosystems A1 Vera Rodríguez, Manuel A1 Gómez Pardo, María Belén A1 Planas, Miquel A1 Castejón Silvo, Inés A1 Bouza Fernández, María Carmen K1 Conservation K1 Genetic diversity K1 Genetic structure K1 Microsatellites K1 Mitochondrial haplotypes K1 Pipefish K1 Seahorses K1 Species identification K1 Syngnathidae AB Spanish National Parks (NPs) are protected areas for biodiversity conservation, including two Maritime–Terrestrian NPs: The Atlantic Islands of Galicia, PNIA (NW Spain) and Archipelago of Cabrera, PNAC (Balearic Islands). This study was aimed to conduct a 3-year genetic survey of syngnathid fish species (i.e. seahorses and pipefish) identified in both NPs and nearby unprotected areas, using mitochondrial and microsatellite markers. A diversity of species was identified with differential distribution among NPs and adjacent areas studied. Pipefish (Syngnathus acus, S. abaster, S. typhle, Entelurus aequoreus, Nerophis lumbriciformis, N. maculatus, and N. ophidion) predominated, while seahorses (Hippocampus guttulatus) were much less abundant. Genetic data and phylogenetic analysis clarified in situ morphological identification. Mitochondrial haplotypes for each species clustered into monophyletic groups, supporting the identification of a cryptic lineage of S. abaster in PNAC distinct from eastern Mediterranean populations of this species. Intraspecific genetic diversity was evaluated at spatial and temporal scale for population samples recorded during the survey period, providing valuable information for individual resampling traceability and delineating management units. Temporal stability in genetic diversity and gene flow with adjacent areas were observed for dominant species within each NP in the 3-year period studied. However, significant intraspecific differentiation was detected between populations identified in Atlantic and Mediterranean NPs. This study provides valuable reference genetic data for future monitoring and to identify distribution or research gaps for further studies towards the conservation of syngnathid populations in Spanish marine NPs, which serve as umbrella species for the preservation of vulnerable coastal ecosystems and habitats. PB Wiley SN 1052-7613 YR 2025 FD 2025-03-17 LK https://hdl.handle.net/10347/42447 UL https://hdl.handle.net/10347/42447 LA eng NO Vera, M., Pardo, B., Planas, M., Castejón-Silvo, I. and Bouza, C. (2025), Genetic Diversity and Connectivity of Syngnathid Fish in Spanish National Parks: Conservation Insights From Protected Marine Ecosystems. Aquatic Conserv: Mar Freshw Ecosyst, 35: e70110. https://doi.org/10.1002/aqc.70110 NO This project was funded by the Spanish Autonomous Agency of National Parks of the Ministry of Agriculture, Food and Environment (HIPPOPARQUES 1580S/2015). Thanks to the team members and collaborators of the coordinated project HIPPOPARQUES (1541S/2015), Xunta de Galicia and responsible personnel of Spanish National Parks for facilitating sampling permits DS Minerva RD 30 abr 2026