A Spectacular Worm

Trying to decide which creature or place from the waters around Long Key to share about first is a challenging task so I'm choosing what will probably be the first animal you will see in the first location we dive at each year during mini-term. The dive site we simply call the worksite. It is an easy place to get in the water for the first time and students have been studying marine life here for years.
The sattelite image pictured above gives an overview of our home base for the week. On the right side is a yellow marker pointing to the roof of the Goshen College Facility where we live for the week. You can see that it boarders the Zane Gray creek or channel that cuts through Long Key. Turtles, sharks, Goliath Groupers and many other interesting things swim right under our dock which overlooks this channel.
On the left side of the image you see the yellow marker which marks the worksite. To reach it we take a 10 minute walk up South Layton Drive, left along Rt 1, and then turn right on a path that cuts through the mangroves to the bayside waters of the ocean. You can see the dark areas under the clear blue water that provide structure (coral, rocks, sponges, grasses) that many of the interesting animals we study live in.
As I mentioned, the last couple years at least, the first animal you are likely to notice as you put your mask under the water is, of all things, a worm. Now that may not sound very exciting to you as your mind pictures the earthworms all over your driveway after a heavy rain here in Ohio but marine worms are an altogether different sort. We see many worms that have appendeges that come off their heads that look look like Christmas trees, others that can be 6 feet long, some that sting like fire, and some that are all the colors of the rainbow. These are from the phylum Annelida and most worms that we  see are segmented worms from the class Polychaeta.
The worm that comes to view very quickly at the worksite is called the Medusa Worm. More often we simply call it Loimia. It's full scientific name is Loimia medusa. Medusa you may recall was the beautiful lady from Greek mythology whose pride in her beauty eventually caused Athena to turn Medusa's lovely long hair into snakes.
It is the extremely long, snake-like "hair" from Loimia's head that gives it the name Medusa.

Of course a worm has no hair but what the diver is seeing are bluish, translucent tentacles that can be as long as 2 feet. To the delight of the student snorkeling in the shallow waters (perhaps 3' deep) at the worksite, not only are Loimia's tentacles interesting to see but if you give any one of the tentacles the slightest touch, they immediately begin to be retracted back into the worms hideout. And a hideout it is. You will likely never lay eyes on the actual Medusa Worm. These worms live in self-constructed tubes which they build out of sand and their own mucus. This tube-building only takes about a half an hour where the young worm grabs sand particles with it's tentacles, brings them back to it's mouth, smears its gooey mucus on the sand, and then builds the tube around itself about twice as long as it's young body so that it can continue to grow inside the tube it has built. They must not be claustrophobic because they live the rest of their lives inside this tube with only their long tentacles reaching out into the ocean searching for it's food which is usually tiny pieces of waste matter or small, decomposing animals. When it finds a tasty morsel, if it is small enough, it slides the food down it's U-shaped tentacle back into it's mouth near the top of it's sandy tube. If the food is too large for this, it will drag the food back to it's mouth by retracting that tentacle.

So the next time you wade into the water off of Long Key, before you go chasing one of the flashy, brightly colored fish, look down and enjoy the amazing Medusa Worm, Loimia medusa.