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Abstract: The ratio of boron to calcium (B/Ca) in the calcite tests of planktic foraminifers may serve as a proxy for past seawater chemistry, but controls on B incorporation are not yet certain. Here we present the results of laboratory culture experiments with live specimens of Globigerinoides ruber (pink) and Globigerinoides sacculifer, which provide new insight into B incorporation controls. We find that in G. sacculifer, B/Ca increases with increasing pH (lower [HCO3 −], higher [CO3 2−] and [B(OH)4 −]), but decreases with increasing total dissolved inorganic carbon (DIC) (higher [HCO3 −] and [CO3 2−], constant [B(OH)4 −]). This suggests competition between aqueous boron and carbon species for inclusion into the calcite lattice. Similar to previous experiments with the subtropical-temperate Orbulina universa, B/Ca increases with salinity, but not with temperature. We evaluate possible carbonate system control parameters, and compare our tropical culture calibrations with new and published core–top data. [Copyright &y& Elsevier]

Anew superfamily,Globigerinitoidea, was designated by BouDagher-Fadel (2012) to represent all the trochospiral, compressed to almost planispiral, smooth, muricate or pustulose-walled, nonspinose planktonic foraminifera that evolved from forms originating in the Cretaceous. Members of this superfamily Globigerinitoidea include the smooth Globanomalinidae, which evolved from Hedbergella holmedelensis in the Danian; the keeled Planorotalitidae, which evolved from the globanomalinids in the Selandian; the pustulose, low trochospiral Tenuitellidae, which evolved from the globanomalinids in the Late Bartonian; and the microperforate, trochospiralGlobigerinitidae, which evolved from the tenuitellids in the Late Priabonian. Unfortunately in BouDagher-Fadel (2012), the Globigerinitoidea superfamily was misattributed and is in fact a new superfamily, and the new family Planorotalitidae was not fully described and here is emended. In addition, a new tenuitellid species, Tenuitellinata praepseudoedita, was suggested by BouDagher-Fadel (2012) but is here defined from a figure originally presented by Li (1987). [ABSTRACT FROM AUTHOR]