In order to assess the dissolution effect on foraminiferal Mg/Ca ratios, we analyzed Mg/Ca of seven planktonic foraminiferal species and four of their varieties from Caribbean core tops from ~900--4700 m water depth. Depending on the foraminiferal species and variety, Mg/Ca start to decline linearly below Δ32-> levels of ~18--26 ¿mol/kg by ~0.04--0.11 mmol/mol per 1 ¿mol/kg Δ32->, similar to decreases of ~0.5--0.8 mmol/mol per kilometer below ~2500--3000 m water depth. Above these species-specific critical levels, Mg/Ca remains stable with higher intraspecific Mg/Ca variability than below. We developed routines to correct Mg/Ca from below these critical thresholds for dissolution effects, which reduce the overall intraspecific variability by ~24--64%, and provide dissolution-corrected Mg/Ca appropriate to calculate Holocene paleotemperatures. When taking into account only dissolution-unaffected Mg/Ca from <2000 m, the systematic succession of foraminiferal species according to their Mg/Ca reflects expected calcification depths.