No. 67–Flowers of the Sea, Part II

In the interest of accuracy I must begin with a clarification regarding last month’s column. In it, while discussing the general morphology of anemones, I stated “The tentacles are armed with stinging cells with the duel purpose of capturing prey and warding off predators.” That is true of many but not all species.

In researching this month’s piece I have learned, among other things, not all anemones have nematocysts (stinging cells) in their tentacles. Some are armed instead with anicontia. Anicontia are thread-like structures covered with nematocysts produced within the column and expelled through the oral opening and pores called cinclides in the outer wall of the column.

One so armed species found locally and on display at the Estuarium is the brown anemone

(Apistasia pallida). Having observed A. pallida for many years, I have now learned that I was long ago misadvised as to its identity and have been calling it a ghost anemone. It turns out there is a ghost anemone (Diadumene leucolena). It just doesn’t live here. I have also been enlightened regarding something that has puzzled me about this creature from the beginning.

Keep in mind that my journey of discovery into the estuarine world began in 1991 with the limited resource material on the arcane available through local libraries. I ventured on line for the first time in 2002.

My first encounter with brown anemones was in the early ‘90s below the Woods Bridge connecting the City of Beaufort and Ladys Island where I saw them nestled amid loose oyster shell litter just below the surface on low tide. They were vertically compact with fleshy brown sienna tentacles. Within a week of being placed in a tank at the North Street Aquarium I had observed an amazing transformation. The brown had melted away and the body columns and tentacles became longer leaving elegant ghostly apparitions of translucent white. You can imagine the aw and puzzlement of a novice naturalist.

That original curious transformation replayed, with a twist, two years ago when I introduced four new brown anemones to tanks at the Estuarium. By chance one was placed in a tank that received ambient sunlight and the other three in one that did not. All four became elongated as before but the one receiving sunlight retained the brown color.

As it turns out, brown anemones in the wild which receive sunlight play host to a type of alga called Symbiodinium microadratiicum. Say that five times quickly. A photosynthetic alga, it converts water and carbon dioxide into carbohydrates consumed by the anemone. All four anemones are regularly fed small bits of shrimp and are doing quite well. The one retaining algae, however, is by far the largest and most prolific in budding clonal offspring. I assume the additional nourishment provided by the algae is responsible.

Several other species of anemone make their home in South Carolina’s near shore waters and estuaries. The Warty anemone (Bunodosoma cavernata) is the largest reaching 3.5” in height and 2” across the oral disc. Its brownish column bares 40 vertical rows of warts. The sea onion (Paranthus rapiformis) is a non-pigmented burrowing anemone that closes tightly into a ball resembling a peeled onion when washed from the sand. Aiptasiogeton eruptaurantia, the red spotted anemone, is one of the easiest to identify by its two to five rows of red tinged cinclides. Native to Japan, the orange striped anemone (Haliplanella luciae) arrived in New England by ship in the 1890s. While quite small, 2cm X 5mm, H. luciae is also very hearty and is now well established on the east and gulf coasts and into the tropics.

I hate giving short-shriff to these creatures and would have liked to have extended the series to do them justice. That, sadly, is not to be however.

Though the exercise of wading through scientific jargon in the pursuit of personal knowledge and an intelligible recounting of same has at times been mind-numbing, I have greatly enjoyed the journey and been pleased with the appreciative response of those who have been along for the ride. My hope is we will be able to reconnect through another publication in the not too distant future and continue the conversation

I thank my friends at Sands Publishing for providing this venue for the past six years and fully understand the economic realities bringing this run to an untimely end.

Best to all.