The distribution of living (rose Bengal stained) Reophax pyriformis Yamashita, Sousa and Kaminski, n. sp., an agglutinated benthic foraminiferal species, was analyzed in the area of the Campos Basin (southeastern Brazilian continental margin). The study is based on 34 oceanographic stations (54 samples), located between 400 m and 3,000 m water depth. The distribution of living Reophax pyriformis n.sp. density is compared to sedimentological parameters, such as total organic carbon, total nitrogen, calcium carbonate, phytopigment, lipids biomarkers (sterols, fatty acids and n-alcohols), total lipids, and bacterial biomass, as well as the particulate organic matter flux to the seafloor. This species was found in the range of 1,000 -1,200 m water depth, with an average living depth of 1.52 cm in the sediment. The distribution of this species seems to be related to lipid biomarkers (allochthone and/or continental derivative, zooplankton and/or fauna, phytoplankton or primary producers) and total organic carbon under the influence of Intermediate Western Boundary Current conditions.
KEYWORDS: agglutinated benthic foraminifera; lipid biomarkers; total organic carbon;Western Boundary Current; Reophax 1988), while R. scorpiurus and R. dentaliniformis may indicate the presence of substrate disturbance caused by rapid sediment deposition or by strong currents (Hess and Kuhnt, 1996).This study focuses on the Campos Basin located on the southwestern margin of the South Atlantic Ocean. The deep-sea benthic foraminiferal assemblages (especially the agglutinated foraminifera are still poorly known in this region of the world.In this geographical context, this work aims to report and describe a new species of Reophax, and to analyze the occurrence and ecology of living (stained) Reophax pyriformis in the Campos Basin.
Study areaThe study area is located between 21°S and 23°S and 38°W and 42°W in the Campos