Buliminid foraminifera from inner neritic sand and mud facies of the Papuan Lagoon, New Guinea

Sixty ''buliminid'' species are recorded from five different physiographic settings within the Papuan Lagoon, southeast coast of New Guinea. Buliminids rarely make up more than 5% of the total foraminiferal content of the sediment, and individual species rarely exceed 1% of the foraminiferal assemblages at any site. Their small test size and low abundance make buliminids inconspicuous components of the microfauna. The most diverse assemblages come from the northwest slope of Horseshoe Reef (medium-coarse sand, 16-53 m water depth; 45 species), from the lagoon basin to the north and west of Motupore Island (mud, 15-38 m water depth; 44 species), and from the fore-reef slope of the fringing reef along the western side of Motupore Island (sand to mud downslope, 10-20 m water depth; 39 species). The least diverse assemblages are from the back-reef flat of Motupore Island (medium-coarse sand, <1.5 m water depth; 16 species) and the eastern channel between Motupore Island and the mainland (medium-coarse sand, <10 m water depth; 15 species). Analysis of the distributions of common species suggests that some occur across a broad facies range (e.g., Loxostomina limbata, Sagrinella lobata, Siphogenerina raphana, Floresina cf. milletti, Buliminoides williamsonianus, Fijiella gr. aculeata, Trimosina gr. spinulosa, Sigmavirgulina tortuosa, Brizalina cf. spathulata, Brizalina gr. striatula, ''Bolivinita'' rhomboidalis) whereas others are confined mostly to either sand facies (e.g., Siphouvigerina porrecta, Trifarina cf. bradyi) or mud facies (e.g., Stainforthia sp., Neouvigerina sp., Fursenkoina schreibersiana). Some appear to have a bathymetric preference within parts of the inner neritic zone (e.g., Cassidelina capitata, Hopkinsinella glabra, Loxostomina mayori, ''Sagrina'' gr. convallarium, Siphouvigerina porrecta, Trifarina cf. bradyi, ''Amphimorphina'' virgula, and ''Bolivina'' subtenuis occur at water depths mostly below 10 m).