soft coral Alcyonium antarcticum

Alcyonium antarcticum is found in Antarctica and the Antarctic Peninsula, South Georgia Island, Kerguelen Island, Heard Island, Burdwood Bank, Falkland Islands, and Argentina from shallow depths down to 642 meters [6,7,8,9,10,11,12]. The color of A. antarcticum is white, grayish white, grayish brown, light rose, orange, pale orange, or orange pink with white tentacles [1,6,7,9,10,11]. A. antarcticum has been measured at population densities of 0.02 and 7.3 colonies per square meter at Explorer's Cove and Arrival Heights respectively [5]. Individual colonies of A. antarcticum live at least 4.5 years and many adults have shown no measurable growth over four years [5].



Alcyonium antarcticum feeds on plankton [3]. It has few predators and is preyed upon by the sea spider Colossendeis megalonyx [2].

A. antarcticum produces chemicals that it releases into the water surrounding itself to deter predators and bacterial growth [4]. These anti-predator chemicals cause tube-foot retraction in the seastars Perknaster fuscus and Odontaster validus [2].

Taxonomic Note: Alcyonium paessleri was synonymized with A. antarcticum in 1992 [6]. The diagnosis of the genus Alcyonium was revised in 1986 [13].

1: Ecological and Faunistic Investigations of the Marine Benthos at McMurdo Sound, Antarctica. John Holmes Dearborn. Ph. D. Dissertation, Dept. of Biological Sciences, Stanford University, 1965; 2: Marine Biology 122(3):461-470, 1995; 3: Science 197:55-58, 1977; 4: Marine Ecology Progress Series 161:133-144, 1997; 5: Antarctic Communities: Species, Structure, and Survival. B Battaglia, J Valencia, and DWH Walton, eds. Cambridge: Cambridge University Press, 1997. pp.309-315; 6: Zoologische Mededelingen 66(1-15):155-181, 1992; 7: Coelentera. I. Alcyonaria. National Antarctic Expedition 1901-1904. Natural History. Volume III. Zoology and Botany (Invertebrata: Marine Algae, Musci). SJ Hickson. London: British Museum, 1907; 8: Die Octactiniarien. AR Molander. Further Zoological Results of the Swedish Antarctic Expedition, 1901-1903. Volume II, Number 2. Stockholm: PA Norstedt & Soner, 1929; 9: American Museum Novitates 2282:1-19, 1967; 10: Annals of the South African Museum 96(6):241-270, 1986; 11: Report on the Alcyonaria Collected by H.M.S. Challenger during the Years 1873-76. EP Wright and T Studer. Report on the Scientific Results of the Voyage of H.M.S. Challenger during the Years 1873-76. Zoology. Volume 31, Part 1 London: Eyre & Spottiswoode, 1889; 12: HJ Broch. Some Octocorals from Antarctic Waters. Scientific Results of the "Brategg" Expedition, 1947-48. Number 5. Publikasjoner Number 26 fra Kommandor Chr. Christensens Hvlafangstmuseum i Sandefjord. Bergen: AS John Griegs Boktrykkeri, 1965. pp.18-38; 13: Journal of Natural History 20(1):53-63, 1986

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