Posted: Nov 20 2010
Naticarius canrena (Linnaeus, 1758), Colorful Atlantic Natica
Posted: Mar 18 2016, Rusty:
Seem to be rather rare treasure coast usually worn down. Much more common keys. Some shell Id books listed this as all along the east coast of fla but I'm rather doubtful of that as their distinct character makes it easy for people to find it as it moves along the gulf current north if conditions are right dead shells especially light weigh gastropods like naticarius canrena can moves a hundred miles north.
3/19/16 Harry Lee:
As we move north along the FL coastline, like N. canrena, many marine mollusks find inshore waters inimical, yet they prosper in offshore waters. This moonsnail is known to live as far N as NC, but, as you suggest, it is seldom cast up on the beach. An exception was Jax Beach during renourishment operations (Lee, 2009: 7), when sediment from ~10 fathoms depth was transported some 10 n.m. and deposited on the seashore.
Other examples are legion, and Lee (2009: 165) indicated a dichotomy between the inshore (pure Carolinian) and the offshore communities, which we might term Caribphile-Carolinian.
There is a name for this change in bathymetric (depth) change in preference: "submergence." This means the progressively deeper habitat of a marine fauna in the cooler waters, e.g., higher latitudes, of its range.
Evidence suggests that most marine mollusks, like many other groups, rely on their larval stages, e.g., veligers, for the maintenance of their distributional patterns.
Lee, H.G., 2009. Marine Shells of Northeast Florida. Jacksonville Shell Club, Inc. 204 pp. + 19 color plates. 28 May.
I observed numerous live or fresh dead specimens in the south end of Jupiter Sound this winter.