Reproduction

E. quadricolor, like all Actiniaria, utilize a number of reproductive modes both sexual and asexual. Asexual modes lead generally to the colonial adult polyps whereas larval settlements post sexual reproduction lead to solitary polyps.

Asexual

Mature E. quadricolor polyps may undergo budding, longitudinal binary fission and pedal laceration. Budding involves a new genetically identical organism developing as an outgrowth of the original mature polyp. Longitudinal fission is common, where an adult polyp splits with each fragment regenerating into a complete genetically identical polyp. Visually, this process resembles two halves of the anemone crawling away from each other. Finally, pedal laceration occurs as segments of the pedal disk break off, each developing into polyps. This may occur if the pedal disk gets snagged and may be released through contraction of the pedal musculature.

Adult polyps are gonochoric and reproduce through synchronous broadcast spawning events during a limited annual breeding season in austral summer and autumn (Scott & Harrison 2007a). Spawning events are thought to be triggered by environmental ques, potentially water temperature, photo period or lunar cycles (Scott & Harrison 2007a). Gametes to be spawned are produced by parallel processes in females and males: oogenisis and spermatogenis respectively. Both process begins with cell derivation in the mesenterial endoderm and a period of growth whilst cells migrate to the mesoglea (Scott & Harrison 2009). Once in the mesoglea them pre-gamete cells proliferate and develop into mature oocytes and spermatozoa (Scott &Harrison 2009). The gametes move out into the gastrovascular cavity as the mesogleal and gastrodermal layers rupture. They are then pumped out of the anemone through muscular contraction of the column (Scott & Harrison 2007a). Clouds of white sperm are released approximately an hour prior to eggs (several thousand eggs released by each anemone) indicating spawning of sperm may trigger oocyte release (Scott & Harrion 2007a). Spawned eggs are green or brown and contain abundant zooxanthellae, indicative of direct transfer of the algal cells (Scott & Harrison 2007a). The eggs are mostly positively buoyant, concentrating at the surface where they are fertilized (Scott & Harrison 2007a).