The Agalega Islands, located in the Western Indian Ocean, are characterized by unique habitats such as enclosed lagoons, sandy shores, and coral reef systems, which offer ideal conditions for rich marine biodiversity. Prior to this study, the gastropod fauna of these islands had remained largely undocumented. The survey was conducted between December 2017 and March 2019 at five survey sites. A total of 705 specimens, representing 119 gastropod species across 25 families, were recorded from the survey sites. Both living and dead specimens were collected to ensure a thorough assessment of species richness, including those residing in less accessible environments, such as reef zones. The Conidae, Cypraeidae, and Muricidae families were found to be the most diverse, collectively representing nearly half of the total species identified. The highest number of species was found at La Fourche station, which represented 29% of the total species, and the lowest percentage of species was recorded at Bato Cassee station (6%). This research established the first inventory of marine gastropods in Agalega, significantly enhancing the understanding of the marine gastropod community and providing a critical baseline for future ecological research.
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