Curator’s Corner

Museum, research, and collection updates from Dr. José H. Leal, plus Shell of the Week, which highlights a different species every other Friday. Most Shells of the Week are found in Southwest Florida.

Dr. José H. Leal serves as the Bailey-Matthews National Shell Museum & Aquarium’s Science Director and Curator. He received his Ph.D. in Marine Biology and Fisheries from the University of Miami and has served at the Museum since 1996.

The Specter Clam

Most bivalve mollusks (clams, mussels, oysters, etc.) are filter-feeders, straining large amounts of water to get their food, usually microscopic plants (phytoplankton). Exceptions to this are marine bivalves that prey on small critters such as crustaceans. These clams, known as septibranch bivalves, use a flexible, muscular "wall", or septum, which acts as a pump, creating a sudden negative pressure that sucks in nearby prey. The Specter Clam, Dilemma spectralis Leal, 2008, a deep-sea dweller f

The Fine-cut Nutmeg

The Fine-cut Nutmeg, Trigonostoma tenerum (Philippi, 1848), is a close relative of the local Nutmeg (Cancellaria reticulata (Linnaeus, 1767), but, unlike this latter, is a very rare shell on local beaches, living in deeper water in the Gulf of Mexico. The Fine-cut Nutmeg is also represented in the Florida fossil record. The shell in this image was found by former Shell Museum volunteer Lois Dunnan on Sanibel in December 2003, and a second Fine-cut Nutmeg was recently found on Blind Pass by avid

The Sanibel Turrid

Did you know that there is one species of marine snail named after Sanibel Island? The species is informally known as the “Sanibel Turrid,” and its scientific name is Crassispira sanibelensis. The species was first described by Smithsonian biologists Paul Bartsch and Harald Rehder, in 1939. The shell, which may reach 30 mm (a little more than an inch) in length, may be found in Southwest Florida and offshore in the Gulf of Mexico. For many years, this member of the family Pseudomelatomidae was m

The Stimpson Chimney Clam

Stimpson Chimney Clam, Rocellaria stimpsoni Tryon, 1861, is a small bivalve that measures about 18 mm (3/4 inch). Chimney clams bore into calcareous substrates such as coral and shells, where they form bottle-shaped dwellings of calcium carbonate (same material as shells). Found locally in valves of Cross-Barred Venus clams (center of image), Ponderous Arks (right), Quahogs, Jewel Boxes, and other bivalve and gastropod shells. In some extreme cases, the bivalve will form dwellings independent o

The Frond Oyster (Duplicated)

Shells of the Frond Oyster, Dendostrea frons (Linnaeus, 1758), can be found on island beaches usually attached to other objects. The shell outline is variable (see pictures), and usually conforms to the shape of the objects the oyster is attached to: very elongate when attached to Sea Whips, or rounded when living on rocks or other hard substrates. Claw-like projections "hook" the shells onto stems of Sea Whips. Frond Oysters belong to the same family as the edible oysters, the family Ostreidae.

Leal Wentletrap

Leal Wentletrap, Epitonium leali García, 2011, is one of about eight species of Wentletraps (family Epitoniidae) that may be found on the beaches of Sanibel and Captiva. The species may be separated by other Wentletraps by the sculpture irregularly sized shell ribs (most ribs are thin, but some may be three or four times as thick as the thin ones), and microscopic spiral lines between the ribs. The uncommon species, which occurs in Florida and the Gulf of Mexico, was named after yours truly by D

The Atlantic Morum

The Atlantic Morum, Morum oniscus (Linnaeus, 1767) has a very characteristic, thick and heavy (for its size) shell with a sculpture of three spiral "rows" of squarish knobs. Its color is whitish or light gray with brown patches. Some shells retain its softer outer, or periostracum, which is dark-gray, velvety. Morum snails were included in the Helmet shell family Cassidae until 1987, when malacologists Hughes and Emerson demonstrated that it belongs within the harp shell family Harpidae. The Atl

The Giant Bittersweet

The Giant Bittersweet, Glycymeris americana (DeFrance, 1826), is the largest species of the Bittersweet family Glycymerididae found in the western Atlantic Ocean, attaining up to 5 inches in size. Shells of the species may be found along the beaches of Sanibel and Captiva after storms. Bittersweets feature a shell hinge that consist of a curved row of a large number of chevron-shaped “teeth” (top of left-hand photo). The hinge teeth in bivalves ensure that the two shell parts, or valves, do not

The Beautiful Semele

The Beautiful Semele, Semele bellastriata (Conrad, 1837), is truly one of the prettiest clams found in our barrier islands. Its shell is never longer than about one inch, and displays a sculpture of concentric ridges and radial ribs that combine to give a “criss-crossed” aspect to the shell surface. The Beautiful Semele is one (and the most attractive) of five species of the family Semelidae occurring in the area. What is remarkable about the Beautiful Semele is its variable coloration, with a b

The Cloudy Periwinkle

The Cloudy Periwinkle, Littoraria nebulosa (Lamarck, 1822), can be found along the coast of Southwest Florida living high above the high tide line on hard surfaces, mostly on dead tree trunks and branches. Periwinkles are marine gastropods that became almost completely independent of the aquatic environment. I took the photo on the right last weekend at Cayo Costa State Park during one of Captiva Cruises trips to the island. The image shows groups of unusually bluish-colored cloudy periwinkles