actinian -- sea anemone, from the scientific term for sea anemones, Actiniaria

Amphiprion -- fish genus containing 27 species, all of which are symbiotic with sea anemones

cnidarian -- member of phylum Cnidaria (also called Coelenterata), the group to which sea anemones, corals, jellyfish, and hydras belong

coelenterate -- member of phylum Coelenterata (also called Cnidaria); see cnidarian

Cryptodendrum -- sea anemones genus containing only one species, which may host anemonefish

Dascyllus -- genus of damselfishes, some species of which are facultative symbionts of actinians, particularly when young

Entacmaea -- genus containing at least two species, one of which is E. quadricolor, the most abundant host sea anemone, which harbours the greatest number of species of clownfishes

facultative symbiosis -- a relationship in which one partner may, but need not, live with another in order to survive; the relationship of most species of host sea anemones with anemonefishes is facultative

Heteractis -- genus containing four species of sea anemones, all of which may host anemonefish

host -- one of the partners in a symbiosis, generally the larger one (thus, the sea anemones that are the subject of this book are hosts to both fish and algal symbionts)

larva (plural larvae) -- a developmental stage that hatches from an egg and that typically lives in a different environment, looks entirely different, and eats different food from the adult of the species; oceanic larvae are generally very small, and are planktonic

Macrodactyla -- sea anemone genus containing only one species, which may host anemonefish

metamorphosis -- the change from larva to adult

melanism -- a tendency to develop black pigmentation, common in many species of anemonefish

mutualism -- a symbiosis in which both partners benefit

nematocyst -- microscopic, harpoon-like stinging capsule manufactured by all cnidarians (= coelenterates)

obligate symbiosis -- a relationship in which one partner must live with another in order to survive; except for a brief planktonic larval stage, anemonefishes are obligate symbionts of sea anemones

parasitism -- a symbiosis in which one partner benefits, to the detriment of the other

plankton -- oceanic plants and animals that drift with the currents; although most planktonic species are small, some, such as jellyfishes, are not

Premnas -- genus containing only one species, which is an anemonefish

Stichodactyla -- genus containing five species of sea anemones, three of which may host anemonefish

symbiont -- one of the partners in a symbiosis

symbiosis -- literally "living together", used by scientists to describe the relationship between unrelated species of plants and/or animals that live in intimate association

taxonomy -- the naming of living beings based on their evolutionary relationships to one another

zoophyte -- literally "animal plant," an archaic term for a sea anemone

zooxanthellae -- single-cell, dinoflagellate (golden-brown) algae that live symbiotically within the cells of some marine animals such as most reef-forming corals, many tropical and a few temperate sea anemones, some hydroids, and all giant clams


This is contribution number 66 of the Christensen Research Institute, Madang, Papua New Guinea. A generous grant from the Christensen Fund gave us the impetus to begin this project, which we had been discussing for a decade. We also acknowledge with gratitude the Director and Board of Trustees of the Western Australian Museum for making the publication of this book possible.

Fellowships to both of us from the CRI contributed to this work. Grants to DGF from the U. S. National Science Foundation (DEB 76-82277), the U. S. National Academy of Sciences (Bache Fund grant 551), the National Geographic Society (grant 1741), the Cocos Foundation, and the California Academy of Sciences are gratefully acknowledged. Some support for the creation of the book was from NSF grant DEB95-21819 to DGF under the Partnerships for Enhancing Expertise in Taxonomy. Susanne Hauswaldt helped in preparation of the electronic version.

Individuals too numerous to mention provided assistance to DGF in the field, museum, and laboratory. She is especially indebted to Jack T. Moyer (Tatsuo Tanaka Memorial Biological Station, Miyake-jima, Japan); Aprilani Soegiarto (formerly of Lembaga Oseanologi Nasional, Jakarta, Indonesia) and his staff including M. Hutomo, Kassim Moosa, and the crew of the R.V. Samudera; Richard N. Mariscal (Florida State University); and John Mizeu and Jean Pierret (CRI). Professor B. Condé, Director of the Nancy Aquarium (Musée de Zoologie de l'Université de Nancy) kindly provided longevity data for captive Amphiprion.

We thank the capable staff of the Publications Department of the Western Australian Museum who greatly asisted us during the production stages: Greg Jackson, Ann Ousey, Desmond Doherty, Vince McInerney and Malcolm Parker. Susanne Hauswaldt helped prepare the text for electronic dissemination.


Allen, G. R. 1972. The Anemonefishes: their Classification and Biology. T. F. H. Publications, Inc., Neptune City, New Jersey, 288 pages.

Allen, G. R. 1973. Amphiprion leucokranos, a new species of pomacentrid fish, with notes on other anemonefishes of New Guinea. Pacific Science 274: 319-326.

Allen, G. R. 1975. Anemonefishes and their amazing partnership. Australian Natural History 18(8): 274-277.

Allen, G. R. 1978. Die Anemonen-fische Arten der Welt. Margus Verlag, Melle, Germany, 104 pages.

Allen, G. R. 1980. Anemonefishes of the World: Species, Care, and Breeding. Aquarium Systems, Mentor, Ohio, 104 pages.

Allen, G. R. and R. N. Mariscal. 1971. A redescription of Amphiprion nigripes Regan, a valid species of anemonefish (family Pomacentridae) from the Indian Ocean. Fieldiana, Zoology 58(8): 93-101.

Bell, L. J. 1976. Notes on the nesting success and fecundity of the anemonefish Amphiprion clarkii at Miyake-Jima, Japan. Japanese Journal of Ichthyology 22(4): 207-211.

Bell, L. J., J. T. Moyer and K. Numachi. 1982. Morphological and genetic variation in Japanese populations of the anemonefish Amphiprion clarkii. Marine Biology 72: 99-108.

Brooks, W. R. and R. N. Mariscal. 1984. The acclimation of anemone fishes to sea anemones: protection by changes in the fish's mucous coat. Journal of Experimental Marine Biology and Ecology 81: 277-285.

Collingwood, C. 1868. Note on the existence of gigantic sea-anemones in the China Sea, containing within them quasi-parasitic fish. Annals and Magazine of Natural History, series 4, 1: 31-33.

Crespigny, C. C. de. 1869. Notes on the friendship existing between the malacopterygian fish Premnas biaculeatus and the Actinia crassicornis. Proceedings of the Zoological Society of London 1869: 248-249.

Cutress, C. E. 1977. Orders Corallimorpharia, Actiniaria, and Ceriantharia. In: Reef and Shore Fauna of Hawaii, Section 1: Protozoa through Ctenophora. D. M. Devaney and L. G. Eldredge, editors. Bernice P. Bishop Museum Special Publication 64, Honolulu, Hawaii, pages 130-147.

Cutress, C. E. and A. C. Arneson. 1987. Sea anemones of Enewetak Atoll. In: The Natural History of Enewetak Atoll. D. M. Devaney, E. S. Reese, B. L. Burch, and P. Helfrich, editors. Office of Science and Technology Information, U. S. Department of Energy, Washington, D.C., pages 53-61 (chapter 6).

Davenport, D. and K. S. Norris. 1958. Observations on the symbiosis of the sea anemone Stoichactis and the pomacentrid fish, Amphiprion percula. Biological Bulletin 115: 397-410.

Doumenc, D. 1973. Notes sur les actinies de Polynèsie Française. Cahiers du Pacifique 17: 173-204.

Dunn, D. F. 1974. Radianthus papillosa (Coelenterata, Actiniaria) redescribed from Hawaii. Pacific Science 28(2): 171-179.

Dunn, D. F. 1981. The clownfish sea anemones: Stichodactylidae (Coelenterata: Actiniaria) and other sea anemones symbiotic with pomacentrid fishes. Transactions of the American Philosophical Society 71: 1-115.

Fautin, D. G. 1985. Competition by anemone fishes for host actinians. Proceedings of the Fifth International Coral Reef Congress, Tahiti 5: 373-377.

Fautin, D. G. 1986. Why do anemonefishes inhabit only some host actinians? Environmental Biology of Fishes 15(3): 171-180.

Fautin, D. G. 1987. Who are those little orange fish and why are they living in a sea anemone? Pacific Discovery 40(2): 18-29.

Fautin, D. G. 1988. Sea anemones of Madang Province. Science in New Guinea 14(1): 22-29.

Fautin, D. G. 1989. Sexual stunts of clownfish. Natural History 9/89: 42-47.

Fautin, D. G. 1990. The anemonefish symbiosis: what is known and what is not. Symbiosis 10: 23-46.

Fautin, D. G. 1992. Anemonefish recruitment: the roles of order and chance. Symbiosis 14: 143-160.

Fishelson, L. 1965. Observations and experiments on the Red Sea anemones and their symbiotic fish Amphiprion bicinctus. Bulletin of the Israel Sea Fisheries Research Station, Haifa 39: 3-14. Fishelson, L. 1970. Protogynous sex reversal in the Anthias squamipinnis (Teleostei, Anthiidae) regulated by presence or absence of male fish. Nature (London) 227: 90-91.

Fricke, H. W. 1973. Individual partner recognition in fish: field studies on Amphiprion bicinctus. Naturwissenschaften 60: 204-205.

Fricke, H. W. 1974. Öko-ethologie des monogamen Anemonenfisches Amphiprion bicinctus (Freiwasseruntersuchung aus dem Roten Meer). Zeitschrift für Tierpsychologie 36: 429-412.

Fricke, H. W. 1975. Selektives Feinderkennen bei dem Anemonen-fisch Amphiprion bicinctus (Rüppell). Journal of Experimental Marine Biology and Ecology 19: 1-7.

Fricke, H.W. 1975. Sozialstruktur und ökologische Spezialisierung von verwandten Fischen (Pomacentridae). Zeitschrift für Tierpsychologie 39: 492- 520.

Fricke, H. W. 1977. Community structure, social organization and ecological requirements of coral reef fish (Pomacentridae). Helgoländer wissenschaftlichen Meeresuntersuchungen 30: 412-426.

Fricke, H. W. 1979. Mating system, resource defence and sex change in the anemonefish Amphiprion akallopisos. Zeitschrift für Tierpsychologie 50: 313- 326.

Fricke, H. W. 1983. Social control of sex: field experiments with the anemonefish Amphiprion bicinctus. Zeitschrift für Tierpsychologie 61: 71-77.

Fricke, H. and S. Fricke. 1977. Monogamy and sex change by aggressive dominance in coral reef fish. Nature 266: 830-832.

Friese, U. E. 1972. Sea Anemones. T. F. H. Publications, Inc., Neptune City, New Jersey, 112 pages.

Godwin, J. and D. G. Fautin. 1992. Defense of host actinians by anemonefishes. Copeia 1992(3): 903-908.

Gohar, H. A. F. 1948. Commensalism between fish and anemone (with a description of the eggs of Amphiprion bicinctus Rüppell). Publications of the Marine Biological Station, Ghardaqa, Egypt 6: 35-44.

Hanlon, R. T. and R. F. Hixon. 1986. Behavioral associations of coral reef fishes with the sea anemone Condylactis gigantea in the Dry Tortugas, Florida. Bulletin of Marine Science 39(1): 130-134.

Lubbock, R. 1980. Death where is thy sting? New Scientist 4: 153-154.

Lubbock, R. 1980. Why are clownfishes not stung by sea anemones? Proceedings of the Royal Society of London 207: 35-61.

Mariscal, R. N. 1969. An experimental analysis of the protection of Amphiprion xanthurus Cuvier & Valenciennes and some other anemone fishes from sea anemones. Journal of Experimental Marine Biology and Ecology 4: 134-149.

Mariscal, R. N. 1970. A field and laboratory study of the symbiotic behavior of fishes and sea anemones from the tropical Indo-Pacific. University of California Publications in Zoology 91: 1-43.

Mariscal, R. N. 1970. The nature of the symbiosis between Indo- Pacific anemone fishes and sea anemones. Marine Biology 6: 58-65.

Mariscal, R. N. 1972. Behavior of symbiotic fishes and sea anemones. In: Behavior of Marine Animals, volume 2. H. E. Winn and B. L. Olla, editors. Plenum Publishing Corporation, New York, pages 327-360 (chapter 9).

Masry, D. 1971. A photographic note on the intimate relationship between a young symbiotic fish Amphiprion bicinctus Ruppell [sic] and its anemone host at Elat (Red Sea). Israel Journal of Zoology 20: 139-142.

Miyagawa, K. and T. Hidaka. 1980. Amphiprion clarkii juvenile: innate protection against and chemical attraction by symbiotic sea anemones. Proceedings of the Japan Academy 56B(6): 356-361.

Miyagawa, K. 1989. Experimental analysis of the symbiosis between anemonefish and sea anemones. Ethology 80: 19-46.

Moyer, J. T. 1976. Geographical variation and social dominance in Japanese populations of the anemonefish Amphiprion clarkii. Japanese Journal of Ichthyology 23(1): 12-22.

Moyer, J. T. 1980. Influence of temperate waters on the behavior of the tropical anemonefish Amphiprion clarkii at Miyake-Jima, Japan. Bulletin of Marine Science 30: 261-272.

Moyer, J. T. and L. J. Bell. 1976. Reproductive behavior of the anemonefish Amphiprion clarkii at Miyake-Jima, Japan. Japanese Journal of Ichthyology 23(1): 23-32.

Moyer, J. T. and A. Nakazono. 1978. Protandrous hermaphroditism in six species of the anemonefish genus Amphiprion in Japan. Japanese Journal of Ichthyology 25(2): 101-106.

Moyer, J. T. and C. E. Sawyers. 1973. Territorial behavior of the anemonefish Amphiprion xanthurus with notes on the life history. Japanese Journal of Ichthyology 20(2): 85-93.

Moyer, J. T. and R. C. Steene. 1979. Nesting behavior of the anemonefish Amphiprion polymnus. Japanese Journal of Ichthyology 26(2): 209-214.

Murata, M., K. Miyagawa-Kohshima, K. Nakanishi, and Y. Naya. 1986. Characterization of compounds that induce symbiosis between sea anemone and anemone fish. Science 234: 585-587.

Ochi, H. 1986. Growth of the anemonefish Amphiprion clarkii in temperate waters, with special reference to the influence of settling time on the growth of 0-year olds. Marine Biology 92: 223-229.

Reed, S. A. 1971. Some common coelenterates in Kaneohe Bay, Oahu, Hawaii. In: Experimental Coelenterate Biology. H. M. Lenhoff, L. Muscatine, and L. V. Davis, editors. University of Hawaii Press, Honolulu, pages 37-51.

Ross, R. M. 1978. Reproductive behavior of the anemonefish Amphiprion melanopus on Guam. Copeia 1978: 103-107.

Ross, R. M. 1978. Territorial behavior and ecology of the anemonefish Amphiprion melanopus on Guam. Zeitschrift für Tierpsychologie 46: 71-83.

Saville-Kent, W. 1893. The Great Barrier Reef of Australia: Its Products and Potentialities. W. H. Allen and Co., London. 387 pages.

Schlichter, D. 1968. Der Nesselschutz der Anemonenfische. Verhandlungen der Deutschen Zoologischen Gesellschaft in Innsbruck 32: 327-333.

Schlichter, D. 1968. Das Zusammenleben von Riffanemonen und Anemonenfischen. Zeitschrift für Tierpsychologie 25: 933-954.

Schlichter, D. 1972. Chemische Tarnung. Die stoffliche Grundlage der Anpassung von Anemonenfischen und Riffanemonen. Marine Biology 12: 137-150.

Schlichter, D. 1976. Macromolecular mimicry: substances released by sea anemones and their role in the protection of anemone fishes. In: Coelenterate Ecology and Behavior. G.O. Mackie, editor. Plenum Press, New York and London, pages 433-441.

Uchida, H., K. Okamoto, and T. Fukuda. 1975. Some observations on the symbiosis between anemonefishes and sea-anemones in Japan. Bulletin of the Marine Park Research Stations 1(1): 31-46.

Verwey, J. 1930. Coral reef studies. I. The symbiosis between damselfishes and sea anemones in Batavia Bay. Treubia 12: 305- 366.

Wood, E. M. Behaviour and social organization in anemonefish. Progress in Underwater Science 11: 53-60.