Zyzzyzus spongicolus (von Lendenfeld, 1884)

Zyzzyzus spongicolus (von Lendenfeld, 1884). C, fertile hydranth with cut-away section in sponge showing digitate rooting processes; D, detailed view of fertile hydranth with actinulae just prior to liberation; E, male gonophore with sperm cells surrounding spadix; F—I, stages in development of actinula — F, cluster of four gonophores in various stages of development, the largest with three eggs; G, early stage growth with developing tentacle buds (actinula dissected out from gonophore); H, newly liberated actinula, I, empty gonotheca after escape of actinula, spadix still present (D, E, F, I, drawn to same scale); J -M , nematocysts — J, K, stenoteles; L, basitrichous isorhiza; M, heterotrichous anisorhiza.

From Watson, J.E. (1978) New species and new records of Australian athecate hydroids. Proceedings of the Royal Society of Victoria 90(2): 301-314.

Photographer: Watson, Jeanette. Publisher: Watson, Jeanette.