Cycloseris cf. hexagonalis (Milne Edwards and Haime, 1848) or Cycloseris cf. tenus (Dana 1846)
Common Names: Plate coral, mushroom coral, disc coral, fungia
Phylum: Cnidaria (stony corals)
Range: Western and Central Pacific Ocean, Indo-West Pacific regions, and the Red Sea
Natural Environment: This stony coral is similar in appearance to Fungia spp., which grow somewhat larger and inhabit various reef environments. This close relative is also a solitary, saucer-shaped photosynthetic stony coral, yet with a somewhat flat, smooth back.
Water Requirements: Calcium 280 to 430 ppm, alkalinity 3.5meq/l, pH 8.1 to 8.2, specific gravity 1.025, and a temperature range of 74 to 83 degrees Fahrenheit (23 to 28 degrees Celsius).
They should be placed on a sandy substrate in areas receiving bright light and moderate water movement. Even though photosynthetic, Cycloseris should be fed at least once per week with meaty foodstuffs, e.g., fortified brine shrimp, Mysis shrimp, products containing cyclops, and/or other marine diced/grated meaty foods. Keep in mind its normally short tentacles are only slightly extended during the day, with further extension occurring in evening hours. Fedding should be at timeframes when tentacles are the most prominent.
Bear in mind also that these corals are phototaxic (move towards light) and can move (even up a slight grade), up to 12 inches (32 cm) per day. SHould it not another coral that is not in its genus, this coral may generate mucus that could cause damage to the species touched.
Do not place it on ledges or rockes where it may fall and be injured.
Even though this is a hardy, disease-resistant coral and somewhat uncommon in the trade, long term survival in the captive system will not be possible unless there is sufficient open substrate areas for this animal to traverse, and its specific nutrition requirements are faithfully adhered to.
The use of "cf"--an abbreviation of the Latin word conferre, meaning to compare--when used before the name of a species suggests the name is tentative and is being used to compare it to an already known correctly described species.
Therefore, two suggested species names are noted above. C. hexagonalis is a species only occurring in the Western Pacific, whereas C. tenuis is more widely spread. Some authors have the shown species identified as possibly being C. hexagonalis, however I doubt this because its color in the wild, i.e., tan or beige, does not match the color of C. tenuis in the wild, which is normally tan or yellowish-orange. More scientific effort is needed to resolve this issue, but until that time arrives, educated guesswork will suffice.