ascidian. probably Synoicum adareanum

Synoicum adareanum is found throughout Antarctica and the Antarctic Peninsula, Kerguelen Island, South Shetland Islands, South Orkney Islands, South Sandwich Islands, and South Georgia Island, from 15 to 796 meters depth [1,2,3,4,6]. S. adareanum colonies consist of large rounded or club-shaped heads with the bottom stalk-like half being wrinkled and leathery and only slightly narrower than the head [1]. S. adareanum colonies can be up to eighteen centimeters high with a diameter of twelve centimeters [1]. S. adareanum colonies may be a single head or up to six heads arising from a single stalk [1,3,5]. The test (body covering) of S. adareanum has been described as firm and cartilaginous or leathery and wrinkled and is semitransparent to glossy [1,5]. The head of a S. adareanum colony is smooth and less firm than the stalk [1]. Synoicum adareanum has been described as orange when alive; sand may be embedded into the test which affects color [1,5,6]. Zooids are large (twelve to twenty millimeters) and arranged in circular rosette systems of six to ten zooids around a conspicuous common cloaca; these systems are evenly distributed over the colonial head [1,5]. One to eight embryos were present in brood pouches in the test of a large collected specimen [1].

Taxonomic Note: Sometimes misspelled Synoicium

1: Antarctic Ascidiacea; Monographic Account of the Known Species Based on Specimens Collected under U.S. Government Auspices, 1947-1965. Kott, Patricia. Washington, DC : American Geophysical Union, 1969. Antarctic Research Series. Volume 13; 2: Patricia (Kott) Mather, personal communication, 1999; 3: Biology of the Antarctic Seas 4:11-82, 1971. Antarctic Research Series 17; 4: Memoires du Museum National d'Histoire Naturelle. Nouvelle Serie. Serie A, Zoologie 125:1-168, plates, 1983; 5: Bulletin du Museum National d'Histoire Naturelle. 4e Serie. Section A, Zoologie, Biologie et Ecologie Animales 16(1):13-37, 1994; 6: Tethys 5(4):611-628, 1974

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