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 Milk Moon Snail

The Milk Moon Snail, Polinices lacteus (Guilding, 1834), is the least common among the shallow-water moon snails (Family Naticidae). The species has a broad distribution in tropical western Atlantic. In geographic areas where the species is more common, its shell may reach in excess of one inch, but the few samples found locally never exceeded 0.5 inch. The Milk Moon Snail has an egg-shaped, smooth, pure white shell with the umbilicus (the cavity on the base, or "lower" part of the shell) partia

The Varicose Cerith

The Varicose Cerith, Alaba incerta (d'Orbigny, 1841), is a small local gastropod that, at 5 mm (about 0.2 inch) in length, fits the definition of a micromollusk (a mollusk with its shell or body equal or smaller than 5 mm.) The Varicose Cerith shell is elegant and very delicate, with translucent walls and the occasional whitish thickening known as a varix. Varices are usually indicative of slower shell growth in gastropod mollusks. Varicose Ceriths are not very common on local beaches, being fou

The Costate Horn Snail

The Costate Horn Snail, Cerithideopsis costata (E.M. da Costa, 1778) is the smaller "sister" to the larger Ladder Horn Snail, Cerithideopsis scalariformis (say, 1825), a species covered in this column on January 13, 2017. Costate Horn Snails may grow to be a little more than 0.5 inch in length. The two species are the only local members of the Horn Snail family Potamididae, a group of marine snails highly adapted to living in brackish waters. Accordingly, the Costate Horn Snail is most commonly

The Tampa Tellin

The Tampa Tellin, Tampaella tampaensis (Conrad, 1866), is a small (up to an inch in length) local member of the diverse bivalve family Tellinidae, the Tellin Clams. Its shell is thin, strong, slightly inflated and roughly elliptical. The shell surface is smooth, except for fine, irregular growth lines that are more visible near the shell margins. The color is opaque-white, rarely pink. The Tampa Tellin is one of those species that is more comfortable living in the back bay areas of Southwest Flo

The Colorful Transennella

The Colorful Transennella, Transennella conradina (Dall, 1884), is a small local member of the megadiverse bivalve family Veneridae, the Venus Clams. This is a small-sized clam, reaching only about 13 mm (about 0.5 inch) at most. Its shape is vaguely triangular, with a smooth shell surface (except for microscopic growth lines). The shell color is white, sometimes with sparse zigzag brown lines. The shell in the images was collected on Sanibel. The Colorful Transennella, Transennella conradina,

The Little Nut Semele

The Little Nut Semele, Semelina nuculoides (Conrad in Hodges, 1841), is a member of the Semele family, the Semelidae. Some of its better-known, local relatives are the Purplish Semele and the Cancellate Semele, both already covered in this column. Unlike these other members of the Semelidae, however, the Little Nut Semele is rather small, with adults measuring at most 6 mm (or a little under a quarter inch). The small size and whitish color make this shell difficult to identify without the help

The Winged Chimney Clam

The Winged Chimney Clam, Gastrochaena difficilis Deshayes, 1855, is a boring clam that spends its life lodged into the structure of empty shells or corals. The elegant shell of this species is very fragile and will not be found outside of its host structure. A young Winged Chimney Clam will settle onto a shell (or coral) and begin the boring process right away. Boring is done chemically, not mechanically. As its close relative, the Stimpson Chimney Clam, does, when its size eventually surpasses

The Mangrove Periwinkle

This is another encore for a local species, as I featured the Mangrove Periwinkle, Littoraria angulifera (Lamarck, 1822), originally in this column on May 29, 2015. As the vernacular name implies, Mangrove Periwinkles inhabit the trunks and branches of mangrove trees, in particular those of the Red Mangrove. Periwinkles may reach 1.25 inches; they are marine snails highly adapted at living completely out of sea water, usually high above the intertidal ("between tides") zone. Mangrove Periwinkles

The Mauve-mouth Drill

Many local species of marine gastropods lay their eggs in protective egg capsules, also known as egg cases. This is just what a female Mauve-mouth Drill, Calotrophon ostrearum (Conrad, 1846) will do. (The species was first covered in this column on April 22, 2016). Their eggs are laid in "crescent-shaped" capsules about 3/16 inch tall, usually on top of the egg cases of larger gastropods. The illustration shows, in addition to views of a shell of the species. two small clusters of egg cases (arr

The Gulf Oyster Drill

The Gulf Oyster Drill, Vokesinotus perrugatus (Conrad, 1846) is one of at least 10 local shallow-water species of the family Muricidae. As the name implies, it uses its radula (ribbon of sharp teeth) to drill holes through the shells of oysters and other bivalve mollusks. The hole provides an avenue for the introduction of chemicals that will initiate the feeding process. At about an inch long, its shell is shaped like a double cone, with a wide range of possible color variations. Females lay eg