STORAGE CELLS AND SPERMATIC CYSTS IN THE CARIBBEAN CORALLINE SPONGE GOREAUIELLA AURICULATA (ASTROSCLERIDAE, AGELASIDA, DEMOSPONGIAE): A RELATIONSHIP ?

Abstract

Ultrastructural observations of the living tissue of the coralline sponge Goreauiella auriculata collected near Discovery Bay, Jamaica and in the Bahamas between 1984 and 2002 were conducted with transmission electron microscopy to pinpoint sexual reproductive stages. Two different structures situated at the base of the living tissue, between processes of the aragonitic skeleton were revealed. Firstly, masses of storage cells packed with various inclusions and resembling gemmular thesocytes were found in all specimens collected in Jamaica; they were scarce and small when male gametes were produced, but none were found in specimens from the Bahamas. Secondly, spermatic cysts containing primary spermatocytes occurred in the same region of the mesohyl on only one occasion. Although in many demosponges male gametes develop directly from choanocytes, we revive the view that the origin of these cells is different in different species. We suggest that storage cells can produce spermatic cysts in G. auriculata.