Diversity and Distribution of the Benthic Foraminifera on the Brunei Shelf (Northwest Borneo): Effect of Seawater Depth

The marine benthic diversity of the Palawan/North Borneo ecoregion is poorly known, despite its implied unique high species richness within Coral Triangle. present study investigated and distribution foraminifera on Brunei shelf. objectives were to determine composition sediment samples collected from 11 sites, extending ~70 km coastline along a depth gradient 10–200 m. We retrieved total 99 species, belonging 31 families 56 genera, out which 52 represented new records for probably ecoregion. Using presence/absence data, analyses also performed compare patterns (species richness, occupancy, taxonomic distinctness) assemblage similarity across sites. For further insight into relationship between depth-associated environmental conditions, we undertook stable isotope selected Rotaliida, Miliolida, Lagenida. Oxygen values positively correlated with distribution, confirming cooler temperatures at greater depth. carbon data revealed differences relating habitat food source specificity biomineralization effect. Close one-third recorded single distinctness increased greatest second deepest site (144 m). Together, these findings suggest underrepresentation diversity, disturbance in shallower water, specialization (adaptation) deeper water. Importantly, suggests occurrence least three biotopes shelf (10–40 m, 40–150 >150 This contributes significantly our understanding local regional foraminiferal distribution.