Early Pliocene to Early Pleistocene; Extinct.
South Florida to Virginia.
Conus adversarius can be differentiated from all other cone shells (living or extinct) by its sinistral, or left-handed, shell coiling: when held with the apex pointing upwards and the aperture opening facing the viewer, the opening is on the left. All other cone shells have dextral, or right-handed shell coiling.
Original Description (from Conrad, 1840, p. 388):
"Shell sinistral, with obsolete spiral lines, except at base, where they are prominent; angle of body whorl, and base of the whorls of the spire carinated; the carina slightly tuberculated towards the apex; spire prominent. Length 2 1/2 inches."
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