Gamete spawning and fertilization in the gymnolaemate bryozoan Membranipora membranacea. From: The Biological Bulletin | Date: October 1, 1994| Author: Temkin, M.H. | COPYRIGHT 1994 Marine Biological Laboratory. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan.  All inquiries regarding rights should be directed to the Gale Group.Copyright information

The simultaneously hermaphroditic zooids of Membranipora membranacea colonies spawn primary oocytes and spermatozeugmata (aggregates of 32 or 64 spermatozoa) into ambient seawater. Eggs are released through the intertentacular organ (ITO) whereas spermatozeugmata are spawned through the tips of the two distomedial tentacles. Fertilized eggs undergo planktotrophic development to form long-lived cyphonautes larvae. Examination of ovarian, coelomic, and spawned oocytes for sperm nuclei, using ei...

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