At sea anemones are marine animals belonging to the Cnidaria phylum and found in intertidal regions, reefs, rocky shores, oceanic islands and, depending on the species, even in mangroves. They belong to the Anthozoa class and have a columnar body with a mouth at the upper end surrounded by tentacles.
It is estimated that there are about 1200 known species. In Brazil, this number drops to 41 different species. The vast majority of anemones are around 10 centimeters tall, but some can reach up to one meter.
These animals are solitary, but we sometimes find clusters of individuals as a result of asexual reproduction. They have a polypoid shape with a fixed portion and a free top, where the mouth is located, surrounded by tentacles. It is noteworthy that some species move slowly in search of a better place for their survival.
As most sea anemones spend most of their lives attached to the substrate, changes in the environment cause serious problems for these animals. The action of waves, tidal changes, siltation, among other factors, are crucial to ensure the survival or not of a given species.
Sea anemones have tentacles with stinging substances
Sea anemones represent an important element in the marine food chain, and are therefore essential for the maintenance of this environment. In addition to serving as food, these animals capture prey, even if they are fixed, with the help of their tentacles, which in turn contain a cell that eliminates an irritant which paralyzes the prey. Among the animals that are part of the diet, we can highlight some species of fish.
Sea anemones can reproduce either sexually or asexually. In the latter form, the formation of a new individual can occur through budding or fission (rupture) processes, for example. Asexual reproduction is common mainly in places that need agile repopulation.
Curiosity: Clownfish can live in harmony with anemones. Although the tentacles of anemones have stinging substances, the clownfish do not suffer any damage when touching this structure. Thus, the anemone serves as a shelter for this small vertebrate.
By Ma. Vanessa dos Santos
