Ward & Blackwelder (1987: 178) stated: "Oliva sayana is a morphologically variable species that is strongly influenced by the environment. Examination of some Holocene collections suggests that more highly spired forms may be associated with certain nearshore conditions and more lowly spired ones with deeper water. We believe the specimens at Lee Creek to represent the low-spired form of this species. The more highly-spired form is figured by Olsson and Harbison (1953: 184, pl. 29: figures 4, 4a). Richards (1968: 112) suggested that the specimen figured by Olsson and Harbison (their Pl. 29: fig 4) may be one of Conrad's type specimens (ANSP 14654). Conrad did not figure his specimen. This species was not recorded by Gardner (1948).".
Apparently, Ward & Blackwelder intended to name the specimens from North Caroliva O. sayana, rather that O. carolinensis. Actually, it is virtually impossible to separate high spired O. sayana-type specimens from low-spire O. carolinensis-type specimens in Caloosahatchee samples from Florida, with many intergrades occurring as well.