Mollusks

Shell of the Week: The Striate Tellin

Measuring at most 20 mm (about 0.8 inch), Serratina aequistriata (Say, 1824) is one of the smallest species of the diverse family Tellinidae occurring on the coast of Southwest Florida. Its shell is thin, delicate, with a sculpture of equally spaced commarginal (“concentric”) lines. As with other tellins, the shell typically has radial ridges on its posterior end, two on the right valve and one on the left. The shell in the photo was collected by Susan J. Hewitt in December 2014, at Blind Pass o

A Shelly Worm Tube

Early this week, Museum staff member Austin Salender found a 40 mm (about 1.6 inch) piece of a Plumed or Ornate Worm (Diopatra cuprea) tube (photo), during one of the Museum’s Beach Walks at Island Inn on Sanibel. Pieces of Plumed Worm tubes are common on our beaches. They are usually covered with seaweed, shell fragments, tiny pebbles, sand grains, pieces of coral, and other marine debris that the worm picks up from its environment and attaches to its tube, which consists mostly of polyssacha

Shell of the Week: The Blake Vitrinella

Solariorbis blakei (Rehder, 1944), is another local member of the microgastropod family Tornidae. Larger shells of the species reach only 1.5 mm (about 0.06 inch), but the shell in the images measures only 1 mm! Its shell is flattened, compressed, with the spire projecting ever so slightly in the early whorls. The shell sculpture consists mostly of wavy axial ridges located near the suture (area where two whorls meet) and shell base. The umbilicus is present, but narrow. The Blake Vitrinella has

Shell of the Week: The Jeanne Vitrinella

Cyclostremiscus jeannae Pilsbry & McGinty, 1946, is another very small local microgastropod in the family Tornidae. The rarely exceeds 2 mm (0.08 inch) in diameter, is flattened, compressed, with a sculpture of three strong spiral keels. The shell base is clearly delimited by the “lower” peripheral keel, with another keel delimiting the relatively large umbilicus. Shell color is white. The species was named after the late malacologist and specialist in Southwest Florida mollusks Dr. Jeanne S. Sc

An Ammonite in Burmese Amber

Who doesn’t like amber? The result of the fossilization of plant resins, amber is a cool-looking, translucent, yellow-orange-brown substance that has been used in the manufacture of jewelry and decorative objects since the Stone Age. Amber is also known for its unique preservation properties, helping conserve otherwise hard-to-fossilize organisms, including small vertebrates, insects, spiders, and a plethora of other animals. Small animals are trapped within the slow-flowing but impervious, mol

The Many Faces of the Twin Drupe

A relatively common species in the tropical western Atlantic, the Twin Drupe, Trachypollia didyma (Schwengel, 1943), is a small (about 15 mm, or 0.6 inch) muricid gastropod that grows from a free-living, pelagic larva into a crawling adult. The larval shell is preserved on the apex of the adult shell as its protoconch. The images show, clockwise from left, a young shell (about 4 mm, or 0.16 inch) captured under a scanning electron microscope (SEM); in color, an adult shell measuring about 12 mm

Super-size Me, Said the Fossil Cowrie!

Reaching 247 mm (about 9.7 inches!), Zoila gigas (McCoy, 1867), a middle Miocene fossil species from Australia, is the largest known cowrie (family Cypraeidae), fossil or living. The shell in this photo, measuring about 7.5 inches, collected in Hamilton, Victoria, Australia, is cataloged in the Museum collection under number BMSM 39220. Read more about mollusks and their shells on the Museum web site.

Shell of the Week: The Trilix Vitrinella

Cyclostremiscus pentagonus (Gabb, 1873) is a member of the microgastropod family Tornidae that grows to be up to 2.2 mm in size. The shell is flattened, compressed, but with the spire projecting in early whorls, sculpture of microscopic growth lines. The last whorl in cross-section has a pentagonal shape. Base with two main spiral ridges. Shell color whitish-translucent, clear. The shell illustrated was collected in 2008 by former Museum collection volunteer Lois Dunnam on the East End of Sanibe

The Secret Life of “Sea Pork”

A common find on the beaches of Sanibel and Captiva, particularly after winter storms, ascidians, also known as “sea squirts” or “sea pork,” are among the most common subjects of inquiries about sea life by island visitors and Museum guests. Recently, I had a chance to pitch in with some information about the subject for the cool online blog Atlas Obscura. Read Jessica Leigh Hester’s article about “sea pork” here. (Photo of Aplidium stellatum near Destin, Florida by Rebekah Danielle Wallace, Un

Shell of the Week: The Amber Melampus

The Amber Melampus, Creedonia succinea (Pfeiffer, 1854), is another local member of the Ellobiidae, a family of air-breathing snails. Shells reach about 3.5 mm (about 1.4 inch), are oval-elongate, translucent, very fragile, thin, with a glossy surface and no perceptible sculpture. The aperture is large, and typically bears two columellar plaits, or “teeth,” with the posterior (“top”) tooth twice as large as the anterior one. The shell color is variable, generally translucent amber, light-brown,