By Riley Renfro
Lettered olives get their name from the intricate hieroglyphic-shaped markings on their outer shells. They can range in color from a pale tan to a deep chocolate brown, with dark purple, yellow, navy, and light lavender marbled in.
The first time I found an olive shell, I didn’t know what it was called. My family must have been hungry because we all agreed that it looked like a burrito, and we have been using that name ever since. These burrito-shaped shells have a distinctive pointed top, and can grow to be anywhere from one to five inches long. Unlike other gastropod mollusks, olive shells do not have an operculum to protect their exposed body. Instead, their tight spiral along the side of their shell provides all the protection they need.
One time, while I was hunting for shells in waist deep water, I brought up a handful of shells and sand with a huge olive on top. I was happy with the find, but when I realized it was alive, I was thrilled! It was amazing to see the creature that lives in these beautiful shells. While I was watching it scoot around in my palm, I could feel it coating my hand in a thick layer of slime. That slimly mucus coating is what gives olive shells their beautiful glossy shine. When the mollusk is moving around on shore, it expands its body and produces mucus to coat the outside of its shell. Once a lettered olive mollusk dies, the shine will slowly be worn away by sand and time until it becomes dull.
Before I returned it to the water, I wanted to snap a picture with my camera which was in my bag. So, I quickly placed it on some wet sand for a moment and dug out my camera. When I turned back, it was already in the process of wedging itself under the sand to hide. It was such a cool experience to see it use its muscular foot, a part of its body, to pull the rest of its shell under, centimeter by centimeter. The shape of its shell was helpful for tunneling, because it was very streamlined and the pointed back end protected it from predators that might come from behind. While it was moving around, it was also leaving behind swirly marks in the sand, like someone had dragged their finger in loop-de-loops. These loops are a great clue that live lettered olives are around.
The lettered olive can be found all over the east coast of the U.S. and on the west coast of Florida, but they are most common in the southeast coast from North Carolina to Florida. In 1984, South Carolina made the lettered olive it’s official state shell. Other species of olives live all around the world. The scientific name of the lettered olive is Oliva sayana, and they live in flat sandy areas close to shore. On the menu for the olive shells are delicate coquina shells and other small bivalves. When an olive shell finds a tiny shell to snack on, it will wrap its muscular foot around its food while dragging it under the sand to pry open and eat.
To reproduce, the female lettered olive mollusk lays 20 to 50 eggs in transparent cases just under the sand in water, to rest and grow for another week before the eggs start to develop into larvae and emerge from their cases. Once they enter the world, they will live on plankton until they have grown into their final forms. The olive shell is not hunted by many other carnivorous shells, but it is a preferred meal for seagulls and crabs. Native Americans used to string them to make necklaces and years later they would also use them to make door coverings to sell to tourists. My family has done something similar when we made olive shell wind chimes. The tips of olive shells commonly break off, there was no need for us to drill them. We were able to thread fishing line through them and make beach themed wind chimes.
In the Olivella genus, there is another olive shell called the variable dwarf olive (Olivella mutica) that is closely related to the lettered olive. The main difference between the two is their size; the variable dwarf olive is exponentially smaller. If you look very closely in shell piles, you can sometimes find the variable dwarf olives mixed in with other minis. My favorite memory of finding a variable dwarf olive was after a big storm on my local beach. The waves had eroded the beach leaving a big drop-off from the seagrapes on the dune to the water. I was walking along and saw a tiny little nub a little lower than eye level with a tip that looked interesting. I gently dug it out with my finger, and it turned out to be a beautiful dwarf olive that was a little over a centimeter long. Such a fun find.
Beside the common lettered olive pattern, there are two other colored patterns, the golden olive and the fulgurator olive. Both are rarer and more coveted than the usual color pattern. The golden olive has a light-yellow color that covers the entire shell. Golden olives have been known to come in shades from a rich honey to the palest yellow. The fulgurator olive, on the other hand, is a dark warm brown color with lighter caramel and tan stripes traveling horizontally across it. I’ve yet to find a fulgator olive, but I am always on the lookout for them. I love how all the color patterns look like Mother Nature painted them with care and love. So next time you find an olive shell, maybe you will think of a burrito.
More about seashells
- Bubble Shells
- The Chambered Nautilus
- Egg-citing Finds: Whelk Egg Casings
- Hidden Beauty: Quahog Shells
- How to Identify Live Sand Dollars
- Identifying Florida Seashells
- Is That Scallop Shell Broken?
- The Red Abalone
- Shark Eyes: The Cannibalistic Mollusk
- Top 10 Sanibel Shells
No live shelling: Be sure shells are empty and sand dollars, sea stars, and sea urchins are no longer alive before you bring them home.
This article appeared in the Beachcombing Magazine May/June 2021 issue.