Mollusks

The Coffee Bean Trivia

The Coffee Bean Trivia, Niveria pediculus (Linnaeus, 1758), is another marine gastropod that can be found occasionally on the island beaches of Southwest Florida. Members of the trivia family, the Triviidae, closely resemble the beloved Cowries (family Cypraeidae), but differ in features of their anatomy and usually by having smaller shells with “wrinkled” sculpture (Cowries are usually very smooth and glossy.) Measuring at most about a half inch in length, Trivias generally feed on colonial as

The Florida Rock Snail

The Florida Rock Snail, Stramonita haemastoma floridana (Conrad, 1837), although relatively common in other parts of Florida, is locally uncommon. This happens because populations of the species need ample rock areas to thrive, and rocks are not prevalent on the barrier islands of Southwest Florida. Rock Snails in the genus Stramonita are known to feed on Oysters and Mussels and may be able to “attack” those prey in groups, to maximize feeding efficiency. Their feeding behaviors include chipping

The Mahogany Date Mussel

The Mahogany Date Mussel, Lithophaga bisulcata (d’Orbigny, 1853) is a rock-boring species, found in calcium carbonate substrates such as live or dead coral and other mollusk shells. The Date Mussel bores into the soft rock using special calcium carbonate-dissolving enzymes that are secreted from the anterior (blunt) end of the animal. The species typically has an elongate, thin-walled, cylindrical shell, which is tapered at its posterior end. A line divides the surface of each valve diagonally.

The Southern Quahog

The Southern Quahog, Mercenaria campechiensis (Gmelin, 1791), is a large member of the Venus Clam family Veneridae that may grow to be 6 inches in size. The Southern Quahog is often found in the shallow, sandy-mud flats of the local bays and protected areas, where it is one of the main food sources for large Horse Conchs and Lightning Whelks. The species is very similar to the Northern Quahog, Mercenaria mercenaria, with which it is known to hybridize in controlled aquaculture settings. (The Nor

The Tampa Bay Top Snail

The scientific name of the Tampa Bay Top Snail, Calliostoma tampaense (Conrad, 1846), pays tribute not only to the place where the species was first found (the specific name tampaense), but also to a shell attribute, via the genus name Calliostoma, the pearly, beautiful (Greek kalos) shell opening, or “mouth” (Greek stoma). Calliostoma top snails are mostly omnivorous or feed on organic detritus, or, more rarely, carnivorous. The Tampa Bay Top Snail never reaches beyond an inch in size and is th

The White Baby Ear

The White Baby Ear, Sinum perspectivum (Say, 1831), is a member of the Moon Snail family Naticidae. As other members of the family do, it feeds on other mollusks, in particular on small clams. This snail’s body is larger than its flattened shell, and the animal is not capable of completely withdrawing into it. The animal spends most of the time burrowed in the sandy bottom and, when fully expanded, its body completely envelops the shell. In addition, to help with burrowing, the White Baby Ear pr

The Nutmeg

The elegant Nutmeg, Cancellaria reticulata (Linnaeus, 1767), is one of the most coveted local species, always representing one of the “best finds” at the end of a successful shelling day. The species name evokes the reticulated shell sculpture and, although the Nutmeg’s food and feeding mechanisms remain unknown, the arrangement of the alimentary system suggests a diet of soft tissue or fluid. The Nutmeg belongs to the family Cancellariidae, a group of marine snails known to feed suctorially, “

The Boring Turret Snail

The Boring Turret Snail, Turritella acropora Dall, 1889, is a relatively common marine snail in the Gulf of Mexico, and often found on the beaches of Sanibel and Captiva. This species is characterized by its sculpture, which includes a series of spiral lines, or cords, which are larger at the periphery of the whorl. Boring Snail Shells can easily be confused with Auger Shells, from which they differ by their rounder aperture (opening) and wider whorls. Boring Snails are closely related to Worm

The Black-foot Slipper Snail

Although the shells from Southwest Florida, as a group, are probably among the best known in the world, there have been a few local species described in relatively recent years, and more are yet to be discovered and named. One of these newcomers is the Black-foot Slipper Snail, Crepidula atrasolea, described in 2000 by Dr. Rachel Collin, now Director of the Smithsonian’s Bocas del Toro Research Station in Panama. In 1997, as a University of Chicago Ph.D. student, Dr. Collin visited Sanibel unde

The Antilles Glassy Bubble

The Antilles Glassy Bubble, Haminoea antillarum (d’Orbigny, 1841), has a very thin, globose, and glass-like shell. Live animals can be seen, sometimes in larger numbers, in the bays and protected seagrass flats of Southwest Florida, in particular during the Spring. Live Glassy Bubbles completely envelop their shells with their bodies. The species is hermaphroditic (both male and female reproductive tracts in the same individual), and the egg mass consists of a transparent and gelatinous, collar-