Marine Invertebrates of Bermuda Giant Caribbean Sea Anemone (Condylactis gigantea) By Marianna Zahra Dr. James B. Wood  Editor Abstract  Taxonomy  Habitat  Ecology  Recent Research  Commercial Importance  Bermuda Laws  Personal Interest  References  Links

Abstract

Condylactis gigantea is a sea anemone found in Bermuda. The common name of this species is the Giant Caribbean Sea Anemone, but it also known as the pink or purple tipped anemone. It is quite common and can be found at many inshore areas on this island. This species tends to be shallow dwelling (Sterrer 1986). This animal reproduces similar to other anemones (Friese 1972). C. gigantea may be confusing to identify due to the variations in pedal disk and tentacle color. Many symbiotic relationships with fish and crustaceans are found with C. gigantea. The most common relationship, with another animal, found in Bermuda is with Periclimenes anthophilus, a cleaner shrimp (Sterrer 1986). Animals that have this symbiotic relationship with this anemone require a period of acclimation in which the animals adapt to each other. This acclimation allows the anemone to recognize that this animal is not prey or a predator (Levine and Blanchard 1980; Crawford 1992). Similar to other cnidarians; this anemone uses nematocysts to protect itself and capture prey and also have a very important symbiotic relationship with zooxanthellae (Sterrer 1986). This toxin found in these nematocysts is the base for much research in the pharmaceutical industry and other medical research (Dellacorte et al. 1994; Zhang and Zhang 1998). Due to its commonness and the fact that it is not exploited in the fishing industry, C. gigantea is not protected by any marine laws in Bermuda.


Taxononmy


Phylum:Cnidaria
  Class:Anthozoa
    Order:Actiniaria
      Family:Actiniida

Habitat


In Bermuda, Condylactis gigantea is very common. This species is only found in the Atlantic Ocean, its range does not extend into the Pacific (Cairns et al. 1991). This anemone can be found at most inshore areas, it may also be found on coral reefs, though this is less common. C. gigantea thrives mostly in shallow water, which is probably a reason why it is common in Bermuda. These shallow water areas include rubble flats; such as Ferry Island area as well as Thalassia (a common Bermuda sea grass) fields; such as Bailey’s Bay (Sterrer 1986). Sea anemones in general however, can be found anywhere from the intertidal zone all the way to a depth of 30,000 feet (Friese 1972).



Often, C. gigantea takes refuge in the crevices of rock walls. It is just as customary to find these animals simply attached to a rock, shell or almost any other object on the sea floor. This does however, provide less protection then hiding in the crevices of a rock wall. C. gigantea is a benthic animal and therefore spends its time, (with the exception of its ciliated planula larvae stage) on the sea floor (Friese 1972). This species of anemone is entirely marine and solitary, though some other species of anemones can tolerate brackish (diluted seawater) water conditions (Friese 1972).

Ecology


All sea anemones have the potential to be either dioecious or hermaphroditic. These animals can also reproduce by division, furrowing to create two genetically identical anemones. Whether they have both male and female sex glands and reproduce asexually, or reproduce with another anemone of the opposite sex, embryos hatch as ciliated planula larvae. This planula will settle on the benthos, develop a pedal disk first and then continue to grow into a fully developed anemone (Friese 1972).



It may be hard to tell Condylactis gigantea apart. While its common name is the Giant Caribbean Sea Anemone, it can also be known as the purple-tipped anemone. The color of both the tentacles and the column differ in each individual. Tentacles may have purple or rose colored tips, green and bright green tips are less common. Or, tentacles may not have any change in color at the tips; but for all C. gigantea, the whole tentacle is a shade of brown or greenish. The column of C. gigantea may be a bluish gray, a shade of yellow, or brick-red (Sterrer 1986). With all their differences, this species of anemone is often confused, and thought to be several species. These are important factors to consider when identifying and collecting C. gigantea.



Since this animal is primarily sessile, mechanisms of defense and protection have been developed. Condylactis gigantea is actually, quite a mobile species, as far as anemones go that is. The form of locomotion that C. gigantea uses is crawling by way of its pedal disk. This movement involves releasing of substrate by the pedal disk, ectoderm contractions for the actual movement, and then the animal adheres itself to desired substrate once again (Robson 1976). This movement is slow however, and is not used in defense or direct protection from predators; anemones do not run from attackers. Instead, if threatened, C. gigantea will greatly reduce its size and draw its tentacles into its gastric cavity. The size is reduced, and room made in the gastric cavity by forcing all most of the water out. If tentacles are not drawn into the gastric cavity, their volume is still reduced almost greatly. This approach to defense allows for the surface area of the animal to be reduced enough to create less chance of a predator attacking it (Friese 1972). Some species of anemones possess acrorhagi, which are stinging tentacle like protrusion that are near the base of actual tentacles (Rupert et al. 2004). Acrorhagi are absent in C. gigantea (Sterrer 1986).



The most effective form of defense in C. gigantea is the use of their nematocysts (stinging cells) which are the defining characteristics of cnidarians. The tips of this anemone’s tentacles are packed with nematocysts that contain a toxin. The nematocysts are the tubular part of cnidarians’ capsule-like cells. When stimulated, these tubules explode out of the capsule and sting the unfortunate attacker (Rupert et al 2004). The sting of these nematocysts is accompanied by the release of a toxin in the species C. gigantea. This toxin is a neurotoxin, a substance that can hinder, injure, or destroy the tissues of the nervous system of some animal that are subjected to its harm. This toxin, in the concentrations found in C. gigantea, is not harmful to humans (Mariscal 1974).



Nematocysts are also used in prey capture. All anemones are carnivores, and will eat a variety of particulate matter and small animals that come in contact with their tentacles (Friese 1972). The nematocysts sting and stun prey that comes in contact with the tentacles and then the sticky tentacles bring this to the mouth for digestion. This species also has a symbiosis with zooxanthellae, and therefore can obtain necessary carbon through means of the photosynthesizing algae (Rupert et al. 2004).



This species of anemone is very popular with other, smaller reef creatures. Condylactis gigantea has many symbioses; Periclimenes anthophilus (cleaner shrimp), Stenorhynchus seticornis (arrow crab) and Apogon spp. (juvenile wrasses). The most common relationship seen in Bermuda is that with P. anthophilus. C. gigantea’s most important symbiotic relationship is that with zooxanthellae, similar to hermatypic corals (Sterrer 1986). Zooxanthellae are important because they provide nutrients to the host. Since C. gigantea is one of the largest anemone species found in Bermuda, it is possible that this is the reason for its symbiosis appeal. These species all find refuge in the tentacles of C. gigantea (Crawford 1992).



It seems that these animals would be harmed by the nematocysts of Condylactis gigantea without some sort of adaptation. Many studies have been implemented concerning how it is that these symbiotic animals are resistant to the toxins in the nematocysts of anemones, namely Condylactis gigantea. The cleaner shrimp, Periclimenes anthophilus, has been documented to go through a period of acclimation where protection from is C. gigantea obtained (Levine and Blanchard 1980; Crawford 1992). This shrimp shows signs of defensive behavior when first introduced to the anemone, in an effort to evade capture (Levine and Blanchard 1980). After an average acclimating time of about two hours and 40 minutes, C. gigantea no longer moves its tentacles from being disturbed by the shrimp, and P. anthophilus no longer shows signs of discomfort from the stings of the anemone. The acclimation of the shrimp is most likely due to a membrane covering the entire animal. This was concluded because in these studies, when shrimps were wiped off and returned to the anemone, they showed signs of needing to acclimate themselves (for a similar amount of time) once again to the anemone’s defenses (Crawford 1992).

Recent Research


Studies of Condylactis gigantea are actually quite helpful in the pharmaceutical and medical industries. By extracting proteins from the tissues, it is suggested that this anemone’s neurons contain neurofilament-like proteins that are molecularly similar to the neurons of mammals. This information would mean that many studies can be done on the evolution of nervous systems by experimenting on present-day cnidarians such as C. gigantea (Dellacorte et al. 1994). Other studies have been done regarding various sea anemone toxins and whether they can be useful in helping various human diseases, symptoms and disorders because of their basic similarities and easy of study. For instance, anemone toxins are beginning to be applied the creation of new drugs that will benefit cardiac troubles. This is due to comparative studies with regard to these toxins possessing “binding affinity for voltage-gated sodium channels of excitable cells” which are critical for cardio stimulant activity (Zhang and Zhang 1998).

Commercial Importance


Studies of Condylactis gigantea are actually quite helpful in the pharmaceutical and medical industries. By extracting proteins from the tissues, it is suggested that this anemone’s neurons contain neurofilament-like proteins that are molecularly similar to the neurons of mammals. This information would mean that many studies can be done on the evolution of nervous systems by experimenting on present-day cnidarians such as C. gigantea (Dellacorte et al. 1994).



Other studies have been done regarding various sea anemone toxins and whether they can be useful in helping various human diseases, symptoms and disorders because of their basic similarities and easy of study. For instance, anemone toxins are beginning to be applied the creation of new drugs that will benefit cardiac troubles. This is due to comparative studies with regard to these toxins possessing “binding affinity for voltage-gated sodium channels of excitable cells” which are critical for cardio stimulant activity (Zhang and Zhang 1998).

Bermuda Laws


This species does not have any special laws that protect it in Bermuda. However, as is the case with all organisms that thrive in the Marine Protected Areas of Bermuda, collection of Condylactis gigantea is not permitted at these areas.

Personal Interest


I find anemones fascinating because so many people do not even think that they are animals. After I found out that the toxin form their nematocysts have real significance, I was intrigued even further. I think it is interesting how anemones are so similar to corals, yet easier to understand in some ways because they are larger and easier to study and transport. It is interesting how something so simple can be so responsive. You would never imagine that these animals have a personality, but when in aquarium, you can tell just by the way they are situated, if they are “happy” or not. I also think it will be interesting to see what discoveries are made using anemone toxin in the future.

References

Cairns, S.D.; Calder, D.R.; Brinckmann, A.; Clovis, C.B.; Pugh, P.R.; Cutress, C.E., Jaap, W.C.; Fautin, D.G; Larson, R.J.; Harbison, W.C.; Arai, M.N.; Opresko, D.M. Common and scientific names of aquatic invertebrates from the United States and Canada: Cnidaria and Ctenophora. American Fisheries Society Special Publication 22. Maryland: American Fisheries Society, 1991.

Crawford, J.A. 1992. Acclimation of the shrimp, Periclimenes anthophilus, to the giant sea anemone, Condylactis gigantea. Bulletin of Marine Science. 50: 331-341

DellaCorte, C; Anderson, D.S.; McClure, W.O.; Kalinoski, D.L. 1994. Neurofilament-like immunoreactivity in the sea anemone Condylactis gigantea (Cnidaria: Anthozoa). Biological Bulletin. 187: 200-207.

Friese, U.E. Sea Anemones. New Jersey: T.F.H Publications, 1972.

Levine, D. and O. Blanchard. 1980. Acclimation of two shrimp of the genus Periclimenes to sea anemones. Bulletin of Marine Science. 30: 460-466.

Mariscal, R.N. 1974. Nematocysts. Coelenterate Biology; Reviews and New Perspectives. 129-178..

Robson, E.A. 1976. Locomotion in sea anemones: the pedal disk. Coelenterate Ecology and Behavior; International Symposium on Coelenterate Biology. 479-490.

Rupert, E.E.; Fox, R.S; Barnes, R.D. 2004. Invertebrate Zoology. Seventh Edition.

Sterrer, Wolfgang., ed. Marine Fauna and Flora of Bermuda: A Systematic Guide to the Identification of Marine Organisms. New York: John Wiley and Sons, 1986.

Zhang, J. and Zhang, P. 1998. Recent advances in structure and function of sea anemone polypeptide neurotoxins. Limnology and Oceanography. Vol. 29, no. 2, 212-218



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