Author Archives: José H. Leal

The Flattened Carditid

In the last two weeks I introduced the bivalves Broad-Ribbed Carditid and Three-Tooth Carditid. Today, to complete the conversation about local members of the family Carditidae, I want to “invite to the podium” the Flattened Carditid, Pteromeris perplana (Conrad, 1841). A small bivalve, reaching only about ¼-inch, this species has a very flat shell, a feature indicated in the specific name, the Latin compound word perplana, which translates into “hyper flat”. The shell is triangular, but with a

The Three-tooth Carditid

Barely reaching quarter-inch, the Three-tooth Carditid, Pleuromeris tridentata (Say, 1826), belongs to the group of relatively abundant but seldom collected small, local bivalves. This species belongs in the same family (the carditidae) as last week's featured shell, the Broad-ribbed Carditid. The shell is inflated, triangular, and relatively thick, with a characteristic sculpture of 15 to 18 strongly beaded radial ribs. (In bivalve shell terminology, radial applies to sculptural elements arrang

The Broad-ribbed Carditid

The Broad-ribbed Carditid, Cardites floridanus (Conrad, 1838), is a common species on our shores. Its shell may reach about 1.5 inches in size, is very thick and relatively heavy for its size. With its sculpture of thick radial ribs, it vaguely resembles and might be confused with local species of Ark Clams. These latter, however, have a shell hinge consisting of many, small teeth that are similar in size; the Carditid, on the other hand, has a hinge with just a few teeth, all different from eac

The Atlantic Semele

The Atlantic Semele, Semele proficua (Pulteney, 1799), is a close relative of the Purplish Semele, Semele purpurascens, a species presented in this column two weeks ago. The Atlantic Semele is a bivalve that may reach about 1.5 inches in size. Its shell is not as colorful as the Purplish Semele: it is usually ivory-white, internally yellow with reddish-brown or mauve speckles. The brownish ligament (the organic part that joins the shell valves and that keeps them slightly open when the animal is

The Chestnut Turban

The Chestnut Turban, Turbo castanea Gmelin, 1791, is a relatively common species of gastropod mollusk from the shores of Southwest Florida. The shell may reach about 1 to 1.5 inches, and is clearly distinguishable from other local gastropods by, among other shell features, the very opening (the aperture), and its sculpture with rows of small, triangular spines. The color is typically of chestnut to light-brown markings on a white background, but there is a local variety with bright orange shell.

The Purplish Semele

The Purplish Semele, Semele purpurascens (Gmelin, 1791), is one of the most distinctive bivalves found along the coast of Southwest Florida. It may reach about 1 to 1.5 inches and is easily distinguishable from other local clams by, among other shell features, its maroon, purplish or sometimes orange color, and presence of a central area of more intense coloration inside the shell valves. The external sculpture consists of very fine commarginal ("concentric") striations, which impart a dull aspe

The Fly Speck Cerith

The Fly Speck Cerith, Cerithium muscarum Say, 1832, received its moniker thanks to its color pattern of interrupted spiral brown lines, which resemble fly droppings against a whitish background. The inch-long species has a sculpture of eight to 11 axial ("vertical") ribs and spiral lines. Fly Speck Ceriths inhabit seagrass habitats, where it feeds on the film of detritus and microalgae growing on seagrass blades. The Fly Speck Cerith, Cerithium muscarum, from Sanibel. Photo by José H. Leal. #

The Circular Chinese Hat

The Circular Chinese Hat, Calyptraea centralis (Conrad, 1841), is a close relative of the more commonly found Slipper Snails. The half-inch species is a gastropod, albeit one with a cap-shaped, circular shell that could easily be mistaken for a little white clam valve. The shell "aperture," on the bottom is represented by a sinuous ("sigmoid"), flaring shelf inside shell. The shell color is invariably white. The Circular Chinese Hat, Calyptraea centralis, from Sanibel Island. Photo by José H. Le

The Southern Marsh Clam

The Southern Marsh Clam, Polymesoda floridana (Conrad, 1846), is a species of bivalve mollusk found locally, mostly in the back-bay areas, including the Caloosahatchee estuary and mangrove habitats. This species has a broad tolerance for changes in salinity. Its adult shell measures from 1 to 1.5 inches; the shell is roughly triangular, with rounded ventral (bottom on the photos) and pointed posterior (left on photos) margins. The shell sculpture is restricted to irregular growth lines. The colo

The Eastern Beaded Chiton

Last week, I introduced the Striate Glass-Hair Chiton, mentioning that that species was the less common of two local shallow-water species of Chitons. Today, I present the other species, the more commonly found Eastern Beaded Chiton, Chaetopleura apiculata (Say, 1838). Chitons belong to a class of mollusks named the Polyplacophora (Greek for "bearers of many plates"). The Chiton shell is divided into eight (rarely seven) plates, or valves. The valves are interlocked, and are surrounded by a tiss