The Florida Prickly Cockle
The Florida Prickly Cockle, Trachycardium egmontianum (Shuttleworth, 1856), is one of the most commonly found bivalves along the shores of Southwest Florida. Its common name originates from the spiny projections distributed along radial (oriented from the “beak” to the edge) ribs. As other species of cockles do, Florida Prickly Cockles use their foot as a “pole vault” or lever to propel themselves away from threatening predators such as Apple and Lace Murexes. Almost pure white shells, known as “albinistic” by collectors, are not uncommon.
The albinistic Florida Prickly Cockle shell depicted in the middle and right images was collected by yours truly under the Blind Pass bridge on Sanibel in March 2010. The posterior view of albinistic shell shows the ligament (brown structure on top). All photos by José H. Leal.