Mollusks

The Atlantic Carrier Snail

The Atlantic Carrier Snail, Xenophora conchyliophora (Born, 1780), is a moderately rare species in the barrier islands of Southwest Florida. Almost all members of the Carrier Snail family Xenophoridae have the ability to cement other shells, shell fragments, worm tubes, corals, and even little pebbles to their own shells. They hold the object to be cemented in place with their foot, then proceed to secrete shell material to affix the object permanently to their own shell edge. Some species speci

The Fargo Worm Snail

The Fargo Worm Snail, Vermicularia fargoi Olsson, 1951, is a gastropod with a shell that starts regularly coiled until it is about an inch long. From then on, the shell then becomes uncoiled, acquiring its typical, irregular shape. The shell “tube” is about 3/8” in diameter. Shells of the Fargo Worm Snail are fairly common along the beaches of Southwest Florida, and so are those of a close living relative previously portrayed in this column, the Florida Worm Snail, Vermicularia knorrii (Deshaye

The Atlantic Petricolid

The Atlantic Petricolid, Choristodon robustus (G.B. Sowerby I, 1834), is an inch-long clam belonging to the Venus Clam family Veneridae. The species is found from North Carolina to Brazil. Shells of other members of the Venus Clam family, such as the Southern Quahog, the Sunray Venus, and the Cross-barred Venus, to name a few, are commonly found along the beaches and bays of Southwest Florida. This is not the case with the shells of the Atlantic Petricolid: the species is present in the area, bu

The Sunray Venus Clam

The Sunray Venus Clam, Macrocallista nimbosa (Lightfoot, 1786), is one of the most attractive members of a very diverse family of bivalve mollusks, the Veneridae. Sunray Venus Clams have shells that vary in color from salmon-pink to brown to grayish-blue. The “Sunray” pattern on the valves is always asymmetrical, i.e, one valve is not a mirror image of the other. A prized shellfish item, the species is being farmed in captivity in parts of Southwest Florida, including Pine Island in Lee County.

The Little Dove Strawberry Cockle

The Little Dove Strawberry Cockle, Americardia columbella H.G. Lee & M. Huber, 2012, is a moderately rare species of the family Cardiidae found in the Gulf of Mexico and along the coasts of Southwest Florida. Its shell has a more triangular shape in relation to other local cockles, and the “pinched” aspect (caused by the presence of a posterior groove, or sulcus) sets it apart from its closest relatives in the genus Americardia. Dr. Harry G. Lee, from Jacksonville, Florida, a past National Shell

The Atlantic Giant Cockle

The Atlantic Giant Cockle, Dinocardium robustum (Lightfoot, 1786), is one of the largest shallow-water bivalves found in the Gulf of Mexico, reaching about 125 mm (6 inches). It is one among eight species of the family Cardiidae present along the shores of Southwest Florida. Its shell is characterized by smooth, rounded radial ribs, usually numbering between 30 and 40 in adult individuals. As it often happens with other species of the family Cardiidae, Atlantic Giant Cockles use their muscular

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

The Lettered Olive

The Lettered Olive, Oliva sayana Ravenel, 1834, is a relatively common species on the beaches and sand flats of Southwest Florida. Despite its relative abundance, it is a desirable, collectible species, certainly because of its glossy, colorful shell, and its assorted variations. The locally famous Golden Olive is nothing but a varietal of the species in which the shell lacks darker pigments. Lettered Olives feed on marine worms, crustaceans, small bivalves, among other prey items. They are fast

The Stiff Pen Shell and its Nacre

The nacreous shell layer of Pen Shells imparts the trademark, dark iridescence that is so typical to the inner surface of Pen and other shells. The nacreous layer, or mother-of-pearl, is composed of thousands of very thin, flat, colorless, translucent calcium carbonate crystals (also known as tablets). These flat crystals cause incident light to scatter and reflect back at different angles, which is perceived as distinctive colors. The tablets are separated thin layers of organic “adhesive,” and

The One-tooth Simnia

One-tooth Simnias, Simnialena uniplicata (G. B. Sowerby II, 1849), are elongated marine gastropods that may reach 20 mm (about 4/5 inch). They live exclusively on the “branches” of Sea Whips, which are colonial organisms related to corals. One-tooth Simnias feed on the mucus of and materials entrapped by Sea Whips, apparently without damaging the Sea-whip polyps. They spend most of their lives on the hosts (except for the time they spend in the plankton as larvae), and may be yellow, white, red