Cheilostomatous bryozoan Cellaria sp.

Cellaria forms erect, tufted, dichotomous-branching colonies attached to the substrate by chitinous rhizoids [1].

Cellaria moniliorata is abundant in the Ross Sea below fifty meters depth [2].


Bryozoans are sedentary animals that form colonies of individuals (zooids) by budding. The external skeletal walls of bryozoans are made with calcium carbonate (calcareous). Bryozoan zooids sit in the equivalent of a calcified box with a gated opening from which a feeding structure is protruded to capture small plankton; food is carried to the mouth with cilial hairs and then sucked into the stomach for digestion.

Sea slugs and sea spiders are the usual predators of bryozoans.

1: Antarctic Cheilostomatous Bryozoa. PJ Hayward. Oxford : Oxford University Press, 1995; 2: Biology and Palaeobiology of Bryozoans: Proceedings of the 9th International Bryozoology Conference, School of Biological Sciences, University of Wales, Swansea, 1992. PJ Hayward, JS Ryland and PD Taylor, eds. Fredensborg, Sweden : Olsen & Olsen, 1994. pp. 205-210

Text © Peter Brueggeman. Photographs © Canadian Museum of Nature (Kathleen Conlan). Photographs may not be used in any form without the express written permission of Canadian Museum of Nature (Kathleen Conlan).