stringy sponge Isodictya setifera

Isodictya setifera is found thoughout Antarctica and the Antarctic Peninsula, South Orkney Islands, South Georgia Island, Falkland Islands, and New Zealand from 0 to 710 meters depth [5,8,10]. I. setifera can be twelve centimeters or more in height [1].


The body of Isodictya setifera can be globular, spherical, cylindrical, finger-shaped, or gradually thickening near the distal end and shaped like a club (clavate); it may have a stalk [1,5]. The color of I. setifera has been described as pink, pale yellow-red, or different shades of yellow [1,2]. I. setifera attaches to rocks or Limatula hodgsoni valves [2].


Isodictya setifera is uncommonly seen, being 0.02% of the benthic surface cover at a Cape Armitage site [2]. I. setifera has been observed to settle and grow to sizes of five and eight centimeters in diameter in a three year period [3,9]. Predators of I. setifera include the seastar Odontaster meridionalis (shown here on I. setifera) and the nudibranch Doris kerguelenensis [2].

Extracts from Isodictya setifera have been shown to have antibacterial activity [4].

Taxonomic Note: Koltun changed the genus to Isodictya and synonymized the species spinigera under I. setifer, but uses the incorrect gender [1,5]. When the genus changed to Isodictya, the species should have changed gender to setifera [6]. Later references usually have it as I. setifera. Homoeodictya is a synonym of Isodictya [11].

1: Sponges of the Antarctic. I. Tetraxonida and Cornacuspongida. VM Koltun. IN: Biological reports of the Soviet Antarctic Expedition, 1955-1958 (Rezultaty biologicheskikh issledovanii Sovetskoi antarkticheskoi ekspeditsii, 1955-1958). Volume 2. EP Pavlovskii, ed. Jerusalem : Israel Program for Scientific Translations. 1966. pp.6-131; Appendix, Index of Latin Names on pp. 443-448; 2: Ecological Monographs 44(1):105-128, 1974; 3: Biologie des Spongiaires, Sponge Biology. C Levi and N Boury-Esnault, eds. Colloques Internationaux du Centre National de la Recherche Scientifique Number 291. Paris : Centre National de la Recherche Scientifique, 1979. pp.271-282; 4: Antarctic Journal of the United States 28:134-135, 1993; 5: B.A.N.Z. Antarctic Research Expedition, 1929-1931, under the command of Sir Douglas Mawson, Kt., O.B.E., B.E., D.Sc., F.R.S., Reports -- Series B (Zoology and Botany). Volume 9, part 4. Porifera -- Part 1: Antarctic Sponges. VM Koltun. Adelaide : Mawson Institute for Antarctic Research, University of Adelaide, 1976; 6: Article 34(b) of the 1985 International Code of Zoological Nomenclature; 7: Marine Fauna of New Zealand: Porifera, Desmospongiae, Part 4 (Poecilosclerida). Bergquist PR and Fromont PJ. New Zealand Oceanographic Institute Memoir 96, 1988; 8: Hooper, JNA & Wiedenmayer, F. Porifera. IN: Zoological Catalogue of Australia. Volume 12. Wells, A, ed. Melbourne : CSIRO Australia, 1994; 9: Biologie des Spongiaires, Sponge Biology. C Levi and N Boury-Esnault, eds. Colloques Internationaux du Centre National de la Recherche Scientifique Number 291. Paris : Centre National de la Recherche Scientifique, 1979. pp.271-282; 10: Polar Biology 12:559-585, 1992; 11: Systema Porifera. JNA Hooper and RWM Van Soest. New York: Kluwer, 2002

Text ©Peter Brueggeman. Photographs ©Norbert Wu. Photographs may not be used in any form without the express written permission of Norbert Wu. Norbert Wu no longer grants permission for uncompensated use of his photos under any circumstances whatsoever; want more info?