Schizoporella unicornis — An Alien Bryozoan Introduced into the Strait of Georgia

• Published in: Journal of the Fisheries Research Board of Canada
• Main Author: Powell, N. A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1970
• Subjects: General Medicine; Crassostrea gigas
• Online Access: http://dx.doi.org/10.1139/f70-201; http://www.nrcresearchpress.com/doi/pdf/10.1139/f70-201

Schizoporella unicornis (Johnston, 1847) has not been recognized in British Columbia previously but is now abundant intertidally in the Strait of Georgia in association with the oyster beds that have been planted there during the past 40 years with Japanese seed of Crassostrea gigas (Thunberg). In the ovicellate Cheilostomata, the breeding female normally develops a single ovicell or brood chamber. A remarkable departure from this condition, however, is demonstrated by the multiples of ovicells occurring in the Canadian population. The occurrence of these in Japanese material of S. unicornis provides additional confirmation of the origin of the British Columbia material.