The marine malacofauna of the Cayman Islands was little studied until the early 1950's, when the Academy of Natural Sciences (Philadelphia) expeditions to Grand Cayman Is. began.  John Dyas Parker, Alfred and Ruth Ostheimer, and R. Tucker Abbott collected extensively, and Abbott (1958) produced a classic monograph on the shelled fauna.  Earlier records were included, but the bulk of the material treated resulted from the ANSP collections.  Jacksonville Shell Club (JSC) member David Hess visited the islands beginning in 1968 and became acquainted with a network of local collectors, including SCUBA divers.  He also consulted scientists specializing in cephalopods and shell-less opisthobranchs.  David added about 100 species to the Abbott report in his contribution to the  extensive survey of the natural history and biogeography of the Caymans (Hess, Abbott et al., 1994).

    JSC member Harry Lee has been sorting sediment samples from the shores and shallows of mostly tropical western Atlantic localities for several years.  Four samples from the Cayman Islands have come under scrutiny: 18 m., Bloody Bay Wall, Little Cayman (Mike Loper! 5/10/02); 15 m., off Georgetown, Grand Cayman (Heidi Lucas! 2/24/03); shore, Cayman Kai, Grand Cayman (H. Lee! 5/16/03); and from a sand chute at the base of a coral head 100 yards off Seven Mile Beach, Grand Cayman Is. (Heidi Lucas! 2/25/04). A total of 184 lots was culled. All specimens are in the H. G. Lee collection.  Since the vast majority of the taxa recorded were micro-mollusks, and this element of the fauna was previously under-represented in the earlier cumulative inventories, it seems appropriate to integrate these records with David's list of names.

    Since 1994 there have been many taxonomic and nomenclatorial alterations, especially in generic placement, which affect the listed species.  In this iteration we follow Turgeon, Quinn, et al. (1998). Aside from these advances, there have been changes in concepts of phylogeny of higher taxa, and conventions in faunal listing sequences have become more standard.  Thus there are several changes of species names and in the arrangement of families and genera.  In the interest of taxonomic rigor, all of the few forma names are removed from consideration.  The ninety-three records from the sediment collections which are new to the cumulative list appear in blue typeface.  The outcome is a substantially modified and extended inventory of 509 taxa.