Intratest Variations in Trace Element Composition of <i>Amphistegina lessonii</i> Using Femtosecond‐Laser Ablation‐ICP‐Mass Spectrometry: A Field Study From Akajima, Okinawa Prefecture, Japan

Abstract Amphistegina are common larger benthic foraminifer in coral reefs, with a nearly circumtropical distribution, and major contributors to the CaCO 3 budget of shallow marine environments. The family Amphisteginidae is dominant Cenozoic carbonates. However, its potential as proxy for paleoclimate reconstruction has not been completely explored. intratest variability trace elements lessonii investigated using femtosecond‐laser ablation‐inductively coupled plasma‐mass spectrometry (fs‐LA‐ICP‐MS). We collected analyzed adult specimens A. September 2003, November January 2004, March from ∼2 m water depth reefs Akajima, Okinawa, Japan. Tests these four collections were Mg/Ca septa observe Test Size‐Lifespan relationships. lifespan specimen 1,200 µm diameter estimated at ∼3 months 900 size. Over lifespans, individual highly variable displays co‐variation temperature tidal heights. Future projects may apply further test this approach tropical paleoenvironments.