Author Archives: José H. Leal

An Alluring Larva!

A couple of weeks ago, underwater photographer Linda Ianiello posted a couple of images in Facebook’s Blackwater Photo Group asking for help with the identification of a veliger larva of a gastropod that she recently photographed in one of her "blackwater" dives*. Veliger larvae are typical of mollusks, and characteristically have the doubled-up, long, paired expansions called velar lobes. Those expansions allow the larvae to move daintily in the water, and bear tiny hair-like cilia that create

Shell of the Week: The Common Sundial

Architectonica nobilis (Röding, 1798) is a marine snail of the sundial family Architectonicidae that may reach in excess of 50 mm (about 2 inches) in diameter. The characteristic, circular, shield-like shell has a sculpture of strong spiral ribs crossed by axial cords, and reddish-brown spots superimposed on a light-cream background. The umbilicus (“hole” on the base) is deep and internally flanked by a wide, segmented band. The species has a very broad distribution from North Carolina to Florid

Shell of the Week: The Beaded Periwinkle

Cenchritis muricatus (Linnaeus, 1758) is a marine snail of the periwinkle family Littorinidae. The species may reach 30 mm (about 1.2 inches), and,as the common name implies, the shell surface is covered with a sculpture of tiny beads. The snails basically live above the high tide line on rocky coasts, exposed coral rock, and other hard substrates. Beaded Periwinkles are capable of climbing vertical rocky cliffs to heights of over 14 meters (about 46 feet). When away from the water, it avoids de

Shell of the Week: The Atlantic Distorsio

Distorsio clathrata (Lamarck, 1816) has the distorted shell that is typical of the family Personidae. The shell in this species may reach 80 mm (about 3.2 inches), and shows the characteristic constricted aperture, large apertural shield, and lattice-like shell sculpture (clathrus is a Greek word for latticework.) The living animal has a very lush and hairy periostracum (outer shell layer). The species is common in deeper water in the Gulf of Mexico, but this is the first shell known to be found

The Intriguing Periostracum of the Pennsylvania Lucine

Lucina pensylvanica (Linnaeus, 1758) is relatively common on the East Coast of Florida, but is very rare or absent from the shores of Southwest Florida. The shell in this species may reach 2 inches in length. It is circular, with marked, commarginal (“concentric”) ridges and a strong posterior groove (the “cut” across the surface of each valve). But what is really cool about this species is its periostracum: it consists of delicate, small, blade-like extensions (in red, below), each ending in a

Shell of the Week: The Rader Angular Triton

Cymatium raderi d’Attilio & Myers, 1984, is a large triton snail of the family Cymatiidae. Its shell is characterized by large, wing-like varices, or the shell expansions manufactured by the snail at irregular intervals. The triangular expansions are similar to, but more accentuated than those in the related species Cymatium femorale, also known as the Angular Triton. The species is found in the Gulf of Mexico, the greater Caribbean to Brazil, but also occasionally off the East Coast of Florida

The Striate Glass-hair Chiton

Chitons belong to a class of mollusks called the Polyplacophora (Greek for “bearers of many plates”). Their bodies are covered by eight (rarely seven) shelly plates, also known as valves. The valves are interlocked and surrounded by a leathery girdle. The Striate Glass-hair Chiton, Acanthochitona pygmaea (Pilsbry, 1893), is one of two species of chitons found in shallow-water along the coast of SW Florida. The Striate Glass-hair Chiton may reach a little more than 0.5 inch in size and its valves

Shell of the Week: The Elegant Venus Clam

The Elegant Venus Clam, Hysteroconcha dione (Linnaeus, 1758), is found in the Caribbean but may be found sporadically off the East Coast of Florida and the Florida Keys. The Elegant Venus Clam has its shell festooned with two rows of prominent spines on the posterior end of each valve. In many sand-burrowing bivalves such as the Elegant Venus Clam, the posterior end faces up, and sometimes sticks out of the sand. The positioning of spines along the posterior end of the shell suggests that they h

Shell of the Week: The Checkered Pheasant

Eulithidium affine (C.B. Adams, 1850), reaches 7 mm (about 0.3 inches), and its small shell is thin, smooth, but strong. The shell is basically devoid of any sculpture, and the color pattern in the species usually consists of a combination of red or pink-red, broad, zig-zag bands overlaid with a number of small red and white dots. The Checkered Pheasant and its close relatives live on Sargassum, other types of seaweeds, and seagrasses. The species is found in shallow water in the Gulf of Mexico,

A Lush Larva

This great image of a veliger gastropod larva highlights the two velar lobes, or the structures that help stabilize the larva in the water and, through the beating action of minute, hair-like cilia along the edges, assist in bringing food particles to the snail’s mouth. The photo, taken by Linda Ianiello, is part of the Museum’s exhibition Black Water: Nocturnal Photography of Open-Ocean Mollusks. The exhibit, open from December 10, 2021 through May 5, 2022, displays images of assorted mollusks