sponge Hemigellius rudis

Hemigellius rudis is found throughout Antarctica and the South Shetland Islands, South Georgia Island, and Kerguelen Island from 20 to 603 meters depth [1,2,5,9]. The body of H. rudis is massive or shaped with curved or rounded projections (lobes), sometimes with thick-walled tubular outgrowths [2,4]. The base of the H. rudis mass may be narrowed and stalk-like [5,9]. H. rudis can be up to twenty-two centimeters high and twenty-seven centimeters in diameter [5].



Sea spider crawling on Hemigellius rudis.

The surface of H. rudis is slightly bristly with large pores and round apical oscules [2,4].



The color of Hemigellius rudis is light gray, beige, or brown [2,4,5].



Hemigellius rudis is firm, hard and crumbles easily [2,4,9].



Probably Hemigellius rudis, with a sea cucumber perched in the middle and a gorgonian on the left.

Taxonomic Note: This taxonomic journey of this sponge is confusing, and is elucidated by Hooper and Van Soest [11]. Earlier authors use Gellius, Haliclona, and Hemigellius [2,3,4,5,6,7,8,9,10].

1: 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; 2: 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; 3: Hooper, JNA & Wiedenmayer, F. Porifera. IN: Zoological Catalogue of Australia. Volume 12. Wells, A, ed. Melbourne : CSIRO Australia, 1994; 4: Ross Sea Expeditions 1987-1988 and 1989-1990, Straits of Magellan Expedition 1991, Data Report Part 3, Physical, Chemical and Biological Oceanography. F Faranda and L Guglielmo, eds. Genova : Repubblica Italiana, Ministry of the University and Scientific and Technological Research, National Scientific Commision for Antarctica, 1994. pp.67-100; 5: Instituto Antartico Chileno. Serie Cientifica 39:97-158, 1989; 6: W de Weerdt and R van Soest, personal communication, 1999; 7: Polar Biology 12:559-585, 1992; 8: The Expedition ANTARKTIS VII/4 (EPOS leg 3) and VII/5 of RV "Polarstern" in 1989. Arntz, W, W Ernst, and I Hempel, eds. Berichte Polarforschung 68:120-130, 1990; 9: Les Demosponges du Plateau Continental de Kerguelen-Heard. N Boury-Esnault & M Van Beveren. CNFRA Number 52, 1982. Paris : Comite National Francais pour les Recherches Antarctiques; 10: Ross Sea Ecology : Italiantartide Expeditions (1987- 1995). FM Faranda, L Guglielmo, A Ianora, eds. Berlin : Springer, 2000. pp. 551- 561; 11: Systema Porifera. JNA Hooper and RWM Van Soest. New York: Kluwer, 2002

IDed as Hemigellius rudis (Topsent, 1901) (Haplosclerida, Niphatidae) by Walentina de Weerdt and Rob van Soest (provided without specimens for checking microscopic details). 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?