Heteractis magnifica

Last updated:

Geographic Range

Heteractis magnifica is found only in the tropical regions of the Indo-Pacific Ocean. Occurring from the Red Sea to Samoa, H. magnifica lives in marine waters of South East Asia, Northern Australia, and the Western Pacific Regions. From Australia, the range of H. magnifica extends all the way to the Ryukyu Islands. (Allen and Fautin, 1992; "Animal-World", 1998; Guck, 2004)

Habitat

Heteractis magnifica is found in marine reefs ranging from 1 to 50 meters deep. It prefers warm waters ranging from 24 degrees C to 32 degrees C. This species resides in clear waters with a strong current. Abundance and colonial or solitary behavior correlates with depth; those that are closer to the surface are solitary and smaller, while those that are deeper tend to form colonies. Animals found to the leeward of the prevailing swell of the water tend to be in denser populations than those in more exposed marine locations. ("Animal-World", 1998; Brolund, et al., 2004; Guck, 2004; Richardson, et al., 1996)

  • Aquatic Biomes
  • reef
  • Range depth
    50 to 1 m
    164.04 to 3.28 ft
  • Average depth
    25 m
    82.02 ft

Physical Description

Heteractis magnifica has the basic morphology of most anemones, living its entire life in the polyp form (looking like a cylindrical column with tentacles). This species has a sticky foot on a pedal disc, and an oral disc which contains the mouth and surrounding tentacles. Heteractis magnifica is the second largest in size of all sea anemones. The oral disc reaches 1 m in diameter or can be as small as 1.25 cm. Typically H. magnifica is between 300 and 500 mm in diameter. The foot, which is used to anchor the animal to various hard surfaces, is also larger than most anemones. The oral disc of an anemone is a flat to slightly curved structure with a mouth in the center, used for both feeding and producing waste. The oral disc can be yellow, brown, or green and is often slightly elevated so that the mouth protrudes out. (Allen and Fautin, 1992; "Animal-World", 1998; Guck, 2004; Horton, 1997)

Many tentacles surround the oral disc; these are located within 20 to 30 mm of the mouth. The lower part of the tentacles closest to the mouth is the same color as the oral disc (usually shades of brown), but the distal portion of each tentacle can vary in color. Tentacles can range in color from red, pink, purple, orange, and green, but are most commonly tannish. Tentacles are about 75 mm long, and some are branched. Heteractis magnifica has characteristic swollen or bulb-like tips on the finger shaped tentacles. Within these tips are cnidocytes, which contain many nematocysts, structures for delivering toxins use in capturing food and defense. (Allen and Fautin, 1992; "Animal-World", 1998; Guck, 2004)

Adult and baby magnificent anemones are very similar in physical appearance. Magnificent anemones lack skeletons and can grow large when nutrient levels are high, but they can shrink when nutrients are scarce. Members of this species can also look like a ball if they contract their tentacles so that only a tuft of tentacles, if any, remain visible. (Guck, 2004)

  • Sexual Dimorphism
  • sexes alike
  • Range length
    .014 to 1 m
    0.05 to 3.28 ft
  • Average length
    .4 m
    1.31 ft

Development

When anemones reproduce sexually, their fertilized eggs develop into a planula larvae which settles on the ocean floor and develops into a polyp. When anemones reproduce asexually, they form new anemones directly from the parent as an exact replica. ("Animal-World", 1998; Guck, 2004)

Reproduction

There are no data on mating systems in Heteractis magnifica. (Guck, 2004)

Heteractis magnifca can reproduce sexually or asexually. In sexual reproduction, the male releases his sperm first to stimulate the female to release her eggs. This external fertilization leads to the development of a ciliated planula larvae. Asexual reproduction can occur by budding, binary fission, or pedal laceration (when part of the pedal disc breaks off to form a new anemone). Most asexual reproduction occurs in the winter. The presence of the symbiotic clown fish Amphiprion chrysopterus can increase the amount of asexual reproduction and general growth. Anemones found with two A. chrysopterus species had faster fission rates than those without this symbiotic species. (Guck, 2004; Holbrook and Schmitt, 2004)

  • Breeding interval
    It is not known how often H. magnifica breeds.
  • Breeding season
    H. magnifica reproduces asexually more frequently in the winter.

There is no parental involvement in the sexual or asexual reproduction process.

  • Parental Investment
  • no parental involvement
  • pre-fertilization
    • provisioning

Lifespan/Longevity

The longevity of Heteractis magnifica in the wild is unknown, but estimated that some of these anemones are hundreds of years old. In captivity, the longest lifespan is 80 years. ("Animal-World", 1998; Guck, 2004)

  • Range lifespan
    Status: captivity
    80 (high) years

Behavior

Heteractis magnifica can be either solitary or colonial. Solitary animals tend to cluster together once they reach a specific size. Some small animals cluster together resembling one large animal, but it is said that these smaller individuals are likely clones. The magnificent anemone is motile when trying to re-position itself to obtain more sunlight. This species moves by creeping on its basal disc, or by letting the tide carry it. Members of this species tend to stay sedentary for most of their lives. Anemones can be semi-aggressive and sting other anemones that invade their space. ("Heteractis magnifica (Family Stichodactylidae)", 2007; "Animal-World", 1998; Brolund, et al., 2004; Guck, 2004)

Communication and Perception

If H. magnifica is attacked, it produces a chemical that is released into the water to warn other anemones that a predator is in the area. The anemone then contracts its tentacles into a ball form for protection. (Mrvos, 2003)

Heteractis magnifica has no ears, eyes, or centralized nervous system. This anemone has nerves in the body wall that are able to communicate with other parts of the body and sense the environment around it. The species possesses three separate nerve "nets" that determine contraction of tentacles in response to the environment. The TCNN and SS1 pathways represent the fast and slow responses of tentacles to mechanical stimulation (for TCNN) and chemical stimulation for the SS1 pathway. Both nerve nets excite the ectodermal muscles via the stimulation of the multipolar nerve net that expands the body of the anemone. The SS1 nerve net, also called the ectodermal slow system, seems to also be responsible for the pre-feeding response (opening of the mouth), and the escape response. (McFarlane and Lawn, 1991; McFarlane, 1984; Mrvos, 2003)

Food Habits

Heteractis magnifica is carnivorous, feeding on small fish, shrimp, isopods, amphipods, mussels, sea urchins, and plankton. This species also absorbs sulfur, nitrogen, and other essential nutrients for growth from the waste of the symbiotic clownfish that live within the tentacles of the anemone. The clownfish also occasionally carries chunks of food to its host.

The anemones use their stinging nematocysts to capture prey that touch them, and then bring them in to the oral disc to digest. They also contain symbiotic algae that produce glucose as a product of photosynthesis, which the magnificent anemone uses. ("Animal-World", 1998; Guck, 2004; Horton, 1997)

  • Animal Foods
  • fish
  • mollusks
  • aquatic or marine worms
  • aquatic crustaceans
  • other marine invertebrates

Predation

Anemones have stinging cells called nematocysts that keep away most predators. The protein toxins that are released are ichthyotoxic; if marine or freshwater fish are exposed to .5 micrograms/mL of the toxin, they die within 2 hours. (Mebs, 1994)

Magnificent sea anemones are hosts to many symbiotic clownfish, which chase away any nibbling predators, especially bristle worms. The clownfish are immune to the nematocysts and gain protection from the anemones' stinging tentacles. ("Animal-World", 1998; Guck, 2004)

Ecosystem Roles

Magnificent sea anemones are prey on fish and invertebrates.

Heteractis magnifica are hosts to many types of clownfish that are resistant to the toxins produced by the anemone. This mutualism benefits both animals, because the clownfish chase away predators of the anemone and bring the anemone food, while gaining protection within the tentacles of the anemone for themselves and their young. Some shrimp also live beneath the oral disc of the anemone, but are not resistant to the toxins. They clean the underside of the magnificent anemone. ("Animal-World", 1998; Guck, 2004)

  • Ecosystem Impact
  • creates habitat

Economic Importance for Humans: Positive

Heteractis magnifica is the most photographed species of anemone and is popular as an aquarium pet. ("Animal-World", 1998)

A new protein "hmGFP" was cloned from the tentacles of H. magnifica. The properties of this protein were homologous to that of the green fluorescent protein (GFP), and it has shown promising possibilities in biotechnology research. (Tu, et al., 2003)

  • Positive Impacts
  • pet trade
  • research and education

Economic Importance for Humans: Negative

Other than its capacity to sting, Heteractis magnifica has no adverse effects on humans. (Horton, 1997)

  • Negative Impacts
  • injures humans
    • bites or stings

Conservation Status

Heteractis magnifica is not listed on the IUCN Red List, CITES appendices, or the US Endangered Species Act list.

Contributors

Stephanie Garbarino (author), University of Michigan-Ann Arbor, Phil Myers (editor), University of Michigan-Ann Arbor, Renee Mulcrone (editor), Special Projects.

Glossary

Australian

Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.

World Map

Pacific Ocean

body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.

World Map

asexual

reproduction that is not sexual; that is, reproduction that does not include recombining the genotypes of two parents

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

colonial

used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

external fertilization

fertilization takes place outside the female's body

fertilization

union of egg and spermatozoan

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

metamorphosis

A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.

molluscivore

eats mollusks, members of Phylum Mollusca

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

phytoplankton

photosynthetic or plant constituent of plankton; mainly unicellular algae. (Compare to zooplankton.)

piscivore

an animal that mainly eats fish

planktivore

an animal that mainly eats plankton

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

radial symmetry

a form of body symmetry in which the parts of an animal are arranged concentrically around a central oral/aboral axis and more than one imaginary plane through this axis results in halves that are mirror-images of each other. Examples are cnidarians (Phylum Cnidaria, jellyfish, anemones, and corals).

reef

structure produced by the calcium carbonate skeletons of coral polyps (Class Anthozoa). Coral reefs are found in warm, shallow oceans with low nutrient availability. They form the basis for rich communities of other invertebrates, plants, fish, and protists. The polyps live only on the reef surface. Because they depend on symbiotic photosynthetic algae, zooxanthellae, they cannot live where light does not penetrate.

saltwater or marine

mainly lives in oceans, seas, or other bodies of salt water.

sedentary

remains in the same area

sessile

non-motile; permanently attached at the base.

Attached to substratum and moving little or not at all. Synapomorphy of the Anthozoa

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

tactile

uses touch to communicate

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

venomous

an animal which has an organ capable of injecting a poisonous substance into a wound (for example, scorpions, jellyfish, and rattlesnakes).

year-round breeding

breeding takes place throughout the year

References

Animal-World. 1998. "Animal-World" (On-line). Magnificent Sea Anemone. Accessed May 17, 2011 at http://animal-world.com/encyclo/reef/anemones/MagnificentSeaAnemone.php.

Australian Government Department of Environment, Water, Heritage, and the Arts. Heteractis magnifica (Family Stichodactylidae). 2601. Australia: Commonwealth of Australia. 2007. Accessed May 17, 2011 at http://www.environment.gov.au/cgi-bin/species-bank/sbank-treatment2.pl?id=81286..

Allen, D., D. Fautin. 1992. "Sea Anemones" (On-line). Field Guide to Anemone Fishes and their Host Sea Anemones. Accessed May 17, 2011 at http://www.nhm.ku.edu/inverts/ebooks/ch1.html#magnifica.

Brolund, T., A. Tychsen, L. Nielsen, M. Arvedlund. 2004. An assemblage of the host anemone Heteractis magnifica in the northern Red Sea, and distribution of the resident anemonefish. Cambridge Journals, 84 (3): 671-674. Accessed May 17, 2011 at http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=224967.

Guck, E. 2004. "Heteractis magnifica" (On-line). Accessed May 17, 2011 at http://bioweb.uwlax.edu/bio203/s2007/guck_eliz/.

Holbrook, S., R. Schmitt. 2004. Growth, reproduction and survival of a tropical sea anemone (Actiniaria): benefits of hosting anemonefish. Coral Reefs, 24 (1): 67-73. Accessed May 17, 2011 at http://www.springerlink.com/content/9xbchpgr5gj64afl/.

Horton, A. 1997. "Anthozoa" (On-line). British Marine Life Study Society. Accessed May 17, 2011 at http://www.glaucus.org.uk/Anemone1.htm.

McFarlane, I., I. Lawn. 1991. The senses of sea anemones: responses of the SS1 nerve net to chemical and mechanical stimuli. Hydrobiologia, 216-217 (1): 599-604. Accessed May 17, 2011 at http://www.springerlink.com/content/p4g80340xv072645/.

McFarlane, I. 1984. Nerve nets and conducting systems in sea anemones: two pathways excite tentacle contractions in Calliactis parasitica. Journal of Experimental Biology, 108: 137-149. Accessed May 17, 2011 at http://jeb.biologists.org/cgi/content/abstract/108/1/137.

Mebs, D. 1994. Anemonefish symbiosis: vulnerability and resistance of fish to the toxin of the sea anemone. Toxicon, 32 (9): 1059-68. Accessed May 17, 2011 at http://www.ncbi.nlm.nih.gov/pubmed/7801342.

Mrvos, R. 2003. "Flowers of the Sea" (On-line). ViaTouch.Com. Accessed May 17, 2011 at http://www.viatouch.com/learn/teacher/articles/sci_sea_anemone.jsp.

Raabe, C., L. Raabe. 2008. "Sea Anemone" (On-line). Accessed May 17, 2011 at http://www.chucksaddiction.com/anemone.html.

Richardson, D., V. Harriott, P. Harrison. 1996. Distribution and abundance of giant sea anemones (Actiniaria) in subtropical eastern Australian waters. Marine Freshwater Research, 48 (1): 59-66. Accessed May 17, 2011 at http://www.publish.csiro.au/paper/MF96020.htm.

Samejima, Y., M. Yanagisawa, Y. Aoki-Tomomatsu, E. Iwasaki, J. Ando, D. Mebs. 2000. Amino acid sequence studies on cytolytic toxins from sea anemone Heteractis magnifica, Entacmaea quadricolor and Stichodactyla mertensii (Anthozoa). Toxicon, 38 (2): 259-264.

Sanamyan, N., D. Schories, K. Sanamyan, H. Krumbeck. 2010. "Radianthus magnifica (Quoy, Gaimard, 1833)" (On-line). Actiniaria.com. Accessed May 17, 2011 at http://actiniaria.com/radianthus_magnifica.php.

Tu, H., Q. Xiong, S. Zhen, X. Zhong, L. WuPeng, H. Chen, X. Jiang, W. Liu, W. Yang, J. Wei, M. Dong, W. Wu, A. Xu. 2003. A naturally enhanced green fluorescent protein from magnificent sea anemone (Heteractis magnifica) and its functional analysis. Biochemical and Biophysical Research Communications, 301 (4): 879-885.