Cycloseris is a genus of mushroom corals (Fungiidae) that live mostly free on sandy substrates. It belongs to the Fungia family, and like other corals of this family, it has recently undergone many taxonomic revisions. In the course of these, species living colonially on substrates have also been included, such as many of the former Cosicinaraea species that have multiple mouths. Interesting new additions are also the former Diaseris species, some of which can self-fragment frags as in Cycloseris (Diaseris) fragilis, making some Cycloseris also propagable. The differentiation of Fungia from Cycloseris is only obvious during development - Fungia are still attached to the substrate as young specimens and detach from it only in the course of growing up with a scar that is also visible later, while Cycloseris grow up completely free.
The identification is also otherwise difficult and the relationships to other mushroom corals are not always easy to distinguish, which results in many mixups, especially because there is an active taxonomic chaos. In the marine aquarium, Cycloseris are easily kept on the aquarium floor. The animals are freely mobile, which must be taken into account when setting up the tank in order to avoid stinging. At night, they may swell up and drift away with the current. They also do not like to be constantly buried by fish such as Digger Gobies, although they can free themselves from sand by peristaltic inflating.
Rather few demands are made on water quality and light. Injuries can be regenerated, it is even possible to fragment them, but they often grow back slowly and the damage is visible for a long time.