Semicassis granulata

Scotch Bonnet - Semicassis granulata

Habitat Found along the East Coast and in water depths of 50-150 ft. They can be found living on sandy substrate as well as rocky tide pools that are close to the shore.

Range The Atlantic Coast from North Carolina to Florida to Brazil

Description As the shells grow, they begin to take on their spiraled egg-like shape and can reach 2-4 inches in length. The base color is white or tan with an overlaying yellow and brown tartan pattern, which give it the plaid appearance. The coloration is very vibrant on the living animal or a fresh empty shell. Once life begins on the beach though the color quickly starts to fade. The scotch bonnet is a gastropod from the same mollusk class as limpets, snails, and slugs.

Ecological Notes Scotch bonnets are predators feeding on keyhole urchins and sand dollars. They cover their prey with their soft bodies and excrete sulfuric acid, which weakens the hard outer layer and exposes the flesh. They use a proboscis structure to feed and consume the exposed tissue. Mating season takes place in the spring after the female scotch bonnet lays thousands of eggs that the male then fertilizes. The eggs hatch into free-swimming planktonic larvae. A shell develops after 14 weeks and life on the ocean floor or sandy beaches begins.

Personal Information I found a scotch bonnet while beach combing in Cape Hatteras.

The scotch bonnet is the official state shell of North Carolina. It received its name due to the resemblance it has to the caps worn by Scottish peasants and the plaid coloration that resembles a Scottish kilt recognizing the early Scottish settlers who came to North Carolina. It became the state shell in 1965 when a state representative by the name of Monice Daniels introduced it to legislation.

References

[Coastal Review Online]

[State Symbols USA]

[NC Pedia]

Additional Information For more information on the scotch bonnet or North Carolina beaches and shells in general, check out these ebooks:

[Peterson First Guide to Shells of North America]

[Seashells of the World]

Contributed by Bethany Linert - 2016

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