<![CDATA[This study was motivated by anthropogenic pressures in the Karangsong Mangrove Area, such as shipping activities, ecotourism, and aquaculture, which have the potential to degrade water quality and affect gastropod diversity as a bioindicator. The study aimed to examine the effects of anthropogenic pressures on water quality and the relationship between water quality and gastropod diversity. Samples were collected in situ at three stations and replicated three times; gastropod identification was conducted on live gastropods including epifauna, infauna, and treefauna within a 5x5 m² observation transect, supplemented by five smaller 1x1 m² transects. Data analysis included community ecological indices, exact permutation tests, PERMANOVA, ANOSIM, SIMPER, and indicator species analysis. The results of the study indicate the presence of anthropogenic pressures on water quality at all three stations. The diversity index values at Stations 1, 2, and 3 were 1.536 ± 0.192, 1.833 ± 0.024, and 1.593 ± 0.110, respectively. Diversity did not differ significantly among stations (exact permutation test, p = 0.111), whereas the Berger–Parker dominance index did (p = 0.004), and gastropod community composition differed significantly among stations (PERMANOVA pseudo-F = 20.01; ANOSIM R = 0.96; both p = 0.003). Indicator species analysis identified seven station-characteristic species, with Sphaerassiminea miniata the strongest indicator of the estuarine station (IndVal = 100; p = 0.033). Keywords: Anthropogenic; Water quality; Bioindicators; Gastropods; Indramayu]]>
