Reproduction and sperm structure in Galeommatidae

Authors: Åse Jespersen Jørgen Lützen

Publish Date: 2006/06/20

Volume: 125, Issue: 3, Pages: 157-173

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Abstract

Reproduction and/or sperm structure was studied in 18 species belonging to five genera of Galeommatidae from Phuket Island Andaman Sea Thailand and Hong Kong Incubation of the ova occurs in the inner and outer demibranchs of both gills and sperm is most probably transferred to the ctenidial brood chamber as masses of agglutinated and nonencapsulated spermatozoa The smallest specimens are males but change into the female sex and there is a strong indication that some of the species are alternate hermaphrodites Dwarf males occur in one species Galeomma layardi The sperm of all 18 species studied are of the entaquasperm type with a more or less hemispherical acrosome that is tilted with respect to the long axis of the moderately elongated nucleus It is suggested that this type of sperm affords the best autapomorphy for the family Galeommatidae

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