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.

Happy Radula-ween!!

Ready to get scared? A radula is the ribbon of teeth used by most mollusks for feeding. Depending on the mollusk, radulas can drill, scrape, slurp, slash, or sting. During my talks on cool molluscan facts I like to showcase the radula of the Magellan Volute, Odontocymbiola magellanica (shown in two views in the illustration), which I consider to be one of the most threatening structures in mollusks! To me, the long cusps on that radula resemble the razor-sharp fingers of the everlasting movie c

Shell of the Week: The Waxy Mangelia

One more member of the large family Mangeliidae, Cryoturris cerinella Dall, 1889) reaches about 12 mm (about 0.5 inch) in length. The shell is very elongate, tower-shaped, with a sculpture of 7–8 strongly angled ribs crossed by fine spiral threads.The aperture spans only about ¼–1/5 of the shell length. The shell color is yellowish­–white, changing to (very) light–orange on last whorl.

Shell of the Week: The Diomedes Mangelia

Continuing with the saga of the large family Mangeliidae, Rubellatoma diomedea Bartsch and Rehder, 1939 reaches about 10 mm (0.4 inch) in length, and has distinctly angled whorls, and a typical “lozenge-shaped” shell. The sculpture includes about 7–10 rounded ribs per whorl crossed by fine spiral striations. The aperture comprises about half the shell length, and the color is white with a couple of broad spiral brown bands more evident on the last whorl. #rubellatomadiomedea #diomedesmangelia #m

Shell of the Week: The Star Mangelia

Once again, another member of the hyper-diverse gastropod family Mangeliidae, Stellatoma stellata Stearns, 1872) grows to about 10 mm (0.4 inch) in length, and has distinctly shouldered (angled) whorls. The spire is high, and the aperture occupies about 1/3 of the shell length. There are about 10–12 prominent ribs on each whorl, and the color is yellowish to light-brown, with the inside surface of the aperture darker in color. #stellatomastellata #starmangelia #mangeliidae

Shell of the Week: The False Mangelia

Yet another member of the hyper-diverse gastropod family Mangeliidae, Pyrgocythara filosa Rehder, 1943 grows to about 7 mm (0.28 inch) in length, and has a sculpture of about 10–12 axial ribs that span the entire whorl, each rib abutting the ones in previous whorls. The ribs are crossed by finer spiral lines. The shell color in this species is very distinctive, with each half-whorl divided into an anterior brown part and posterior cream-colored one. #pyrgocytharafilosa #falsemangelia #mangeliida

Shell of the Week: The White Mangelia

Another member of the very diverse gastropod family Mangeliidae, Tenaturris bartletti (Dall, 1889) has a body whorl comprising about half of the shell length in adult individuals, and a proportionately larger last whorl in juveniles. The sculpture consists of about 15 axial ribs crossed by fine spiral threads, and the entire shell surface has a “frosty” appearance. #tenaturrisbartletti #mangeliidae #whitemangelia #sanibel

Shell of the Week: The Spear Mangelia

Ithycythara lanceolata (C.B. Adams, 1850) is a slender-shelled mangeliid gastropod that grows up to 12 mm. The shell sculpture consists 6–8 well-marked axial ribs. Rib may form a “peak” in the middle of each whorl, where the whorl is wider. The shell is relatively abundant off the East Coast of Florida, but is also present in the Gulf of Mexico. The shell is usually white, but may present reddish-brown hues, mostly at the anterior end. The shell in the illustration was collected in December 1997

Upside-down Baby!

In gastropod mollusks, the larval shell ("baby" shell, or protoconch), is usually retained in the apex (the "tip") of the adult shell. After metamorphosis from larva to adult, there may be differences in color, thickness, and texture between the protoconch and the adult shell, but usually the direction of coiling stays the same with growth. Gastropods with a right-handed larval shell continue to grow a right-handed adult shell, and vice versa.An exception to this same‐coiling-direction "rule" is

Metamorphosis in a Sea Snail

In a way that is analogous to what happens when a caterpillar becomes a butterfly, the change in lifestyle from a pelagic (open-water dweller) larva to a bottom-living adult is also known as metamorphosis. The illustration presents three shell-growth stages of an Atlantic Gray Cowrie, Luria cinerea (Gmelin, 1791). From left: the planktonic (free-living) larval shell; juvenile shell briefly after settlement to the bottom-living stage; and adult shell. They are all so different, yet all are stages

Cowries are Cool!

Throughout human history, the enjoyment of shells and curiosity they spark have been the foundation for the science and better understanding of mollusks. And no other group of shells evokes more interest and appreciation than cowries (family Cypraeidae). Their “egg-shaped” shells are usually smooth, glossy, and their weight “feels” just right when held in one's hand. From time to time the living snail covers the shell from both sides of a slit-like opening, and the shell-making mantle repairs bl