Depth distribution of modern larger benthic foraminifera offshore Brunei Darussalam

The present study provides new data on the diversity, abundance and depth distribution of larger foraminifera (LBF) from a number of sites offshore BruneiDarussalam. This region, indeed very close to the modern LBF hotspot diversity, has always been overlooked and no data are available to date. The investigated sites are called Pelong rocks, Abana Reef, Oil RigWreck, AmericanWreck, AustralianWreck and BluewaterWreck. Altogether, 16 taxa ofmodern LBF have been identified and the most common families are the Amphistiginidae, Calcarinidae and Nummulitidae. The purpose of this study is to estimate the depth distribution of each recovered LBF species and to compare it with that known from other localities in the Indo-Pacific realm to check for similarities and differences in environmental and ecological conditions. Such comparisons are very important as LBF depth distributions are strongly influenced by light penetration in the water column and sea floor substrate. Bruneiwaters are generally rich in suspendedmaterial due to the large rivers discharging in the Brunei Bay, and the sea floor is mostly covered by finemud where LBF have never been reported. The data come from recently sampled sandy patches where LBF flourish and they depict a relatively high biodiversity, which seems to be comparable with the values available for the nearby located diversity hotspot.