Bubble-Tip Anemone

Entacmaea quadricolor is widespread throughout the tropical waters of the Indo-Pacific area, including the Red Sea.

E. quadricolor anemones appear in a variety of morphs, including rose, orange, red, and standard green. This sea anemone can grow to be up to 30 centimetres (0.98 ft) in diameter, and obtains the majority of its energy from solar radiation via its symbiotic zooxanthellae.

A characteristic of E. quadricolor is its ability to maintain a symbiotic relationship with the anemonefish, which can be "hosted" by the anemone by providing it with defence against predators and also providing some nourishment. In turn, the anemone provides the anemonefish with shelter.

Nutrients are generally obtained by filter feeding using its sweeping tentacles, or through wastes and debris cleaned from the surface of its partner anemonefish.

E. quadricolor exhibits a variety of reproductive strategies. The most common strategy would be a form of sexual reproduction called broadcast spawning. This is considered the main form of reproduction and occurs at the start of the year between January and April for those in eastern Australian waters. During these times, E. quadricolor will release its gametes into the water column and form free-swimming planula larvae. These larvae of E. quadricolor have been observed to survive up to 59 days in the water column, with peak settlement occurring around 10 days. This time of suspension allows for greater dispersal and increases genetic diversity for the species. Once the larvae settle, they will then begin to further develop and start the cycle once more.

E quadricolor is not currently listed on the IUCN Red List of Threatened Species, but it is facing hardships with global climate change and anthropogenic activities. Anthropogenic activities have increased atmospheric carbon dioxide and consequently global temperatures are predicted to raise by 4.3 °C while seawater pH is likely to decrease by 0.3 units. It has been observed that future ocean temperatures will cause bleaching in E. quadricolor, whereas increased pCO2 generally had no significant effects on the anemone. Coral bleaching events will have detrimental impacts on host sea anemones and the symbionts as a result of climate change.