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

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 t...

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Bibliographic Details
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:
Online Access:http://dx.doi.org/10.1139/f70-201
http://www.nrcresearchpress.com/doi/pdf/10.1139/f70-201
Description
Summary: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.