Abundance and Diversity of Gastropoda Associated with the Mangrove Ecosystem in Jor Bay, West Nusa Tenggara Province, Indonesia

Abstract

Mangrove ecosystems support diverse benthic communities, including gastropods that contribute to litter breakdown and may reflect habitat condition. This study assessed the genus-level composition and community structure of gastropods in the mangrove ecosystem of Jor Bay, East Lombok Regency, West Nusa Tenggara Province, Indonesia. Field sampling was conducted in April 2026 using a stratified random design across ten stations. At each station, gastropods were collected from three 1 × 1 m subquadrats established within a 10 × 10 m quadrat. Specimens were identified to genus level, and abundance, Shannon–Wiener diversity, Pielou’s evenness, and Simpson’s dominance indices were calculated. In total, 606 individuals representing nine genera were recorded at eight stations. The genera identified were Nerita sp., Terebralia sp., Littorina sp., Nassarius sp., Turricula sp., Clypeomorus sp., Chicoreus sp., Cerithidea sp., and Telescopium sp. Terebralia sp. was the most abundant and dominant genus, whereas Telescopium sp. was the least abundant. Diversity values ranged from 0.7436 to 1.3418, indicating low to moderate diversity. Evenness values ranged from 0.4620 to 0.9023, representing moderate to high evenness, while dominance values ranged from 0.3956 to 0.6575. Muddy substrates predominated at the stations where gastropods occurred and were associated with the widespread occurrence of Terebralia sp. These findings provide baseline information on the spatial variation and community structure of mangrove-associated gastropods in Jor Bay.