Now What, Broken Shells?
Not quite... The photo shows two Alphabet Cone (Conus spurius Gmelin, 1791) shells that have been clipped by predators, most likely Stone or Flame crabs. The resulting gashes reveal that parts of the earlier whorls located inside the shell have disappeared. In each shell only the columella, or central pillar, was left behind. Most likely, dissolution of the inner parts in these shells was not a result from the crabs’ fondness for molluscan meals. Some cone snails, along with other gastropods, are known to dissolve their internal shell structures. Oddly enough, one of the ensuing benefits, in particular to cones snails that feed on fish or mollusks, is that the new, roomier internal space enables the animal to swallow larger prey. In addition, some cone species are known to recycle the dissolved shell material to reinforce and thicken the outer shell wall. This certainly makes it harder for shell-clipping predators, such as crabs, from trying to get that cone snail meal. The columella is “saved” from dissolution, as it is the main area of attachment of the snail to its shell. The shells in the photo were found by Lorin Buckner at the Blind Pass area of Sanibel, in December 2018. These Alphabet Cones are catalogued in the Museum collection under number BMSM 127507. Please support collection-oriented research at the Museum by making a gift to our collection department!