A new species of glowing snail discovered in the Florida Keys has been named after the region’s popular cocktail.
The Margarita snail’s distinctive citrus coloring could help ward off predators, scientists say.
The Keys, a series of tropical islands stretching about 100 miles off the southern tip of Florida, are home to the only living coral reef in the continental United States and many animals found nowhere else in the world.
The newly discovered Margarita snail and its lime green cousin from Belize are the subjects of a new study published in the journal PeerJ.
A new species of glowing snail discovered in the Florida Keys has been named after the region’s popular cocktail
Scientists say the sea snails are distant relatives of the land-dwelling snails that are often found in gardens and leave slimy trails behind.
They are also called “worm snails” and spend most of their lives in one place.
The lead author of the study, Dr. Rüdiger Bieler, said: “I think they are particularly cool because they are related to common free-living snails, but when the young find a suitable place to live, they hole up, cement their shell to the substrate and never move again.” .
“Its shell grows as an irregular tube around the snail’s body, and the animal hunts by spreading a web of mucus to capture plankton and pieces of detritus.”
Bieler has spent the last four decades studying invertebrates living in the western Atlantic, but these particular snails “are so small and so well-hidden that we have never seen them before in our diving surveys.”
He said: “We had to look very closely.”
Bieler, curator of invertebrates at the Field Museum in Chicago, says the new species belongs to the same family of sea snails as the invasive “Spider-Man” snail that the same team described in 2017 at the Vandenberg shipwreck off the Florida Keys.
He and his colleagues, including Field Museum curator Petra Sierwald, encountered the lemon-colored snails at the Florida Keys National Marine Sanctuary and found a similar, lime-colored snail in Belize.
The Margarita snail’s distinctive citrus coloring could help ward off predators, scientists say
Dr. Bieler said: “Many snails are polychromatic – there are different colors within the same species.”
“In a single population, even in a single small cluster, one could be orange, one could be gray.”
“I think they do it to confuse fish and not give them a clear target, and some have warning coloration.”
He added: “When I initially saw the lime green and the lemon yellow species, I thought they were the same species.”
“But when we sequenced their DNA, they were very different.”
Based on the molecular data, Dr. Bieler and his colleagues assigned the snails to a new genus, Cayo, after the Spanish word for a small, low island.
He explained that the yellow snail was named Cayo Margarita after the citrus drinks in Jimmy Buffet’s song “Margaritaville.” The name of the lime snail, Cayo galbinus, means “greenish-yellow”.
Dr. Bieler says the Cayo snails share an important feature with another genus of worm snails, Thylacodes, for which the team described a new species from Bermuda and named it Thylacodes bermudensis.
Although they are only distantly related, all snails have colorful heads that protrude from their tubular shells.
Dr. Bieler said: “In our opinion, this is a warning color.”
“They have some nasty metabolites in their mucus.” That might also explain why they can have exposed heads – on the reef everyone is out to eat you, and if you don’t have a defense mechanism you’ll get attacked by corals, sea anemones and all that overgrows things around you.
“It seems like the slime might help keep neighbors from getting too close.”
He added: “Global water temperatures have been rising and some species are coping much better than others.”
“The Cayo snails tend to live on dead pieces of coral, and as more coral is killed, the snails can spread.”
“It’s another indication that we have undescribed species right under our noses.”
“This is snorkeling depth in a heavily touristed area, and we are still discovering new things all around us.”