Astroides calycularis (Mediterranean Cup Coral) Care Guide
Astroides calycularis is a temperate Mediterranean non-photosynthetic cup coral, bright orange and requiring coolwater conditions, not a tropical reef.
Compiled by Aquairi from published sources · Published · Updated
Overview
Astroides calycularis is a colonial stony coral of the family Dendrophylliidae, endemic to the western Mediterranean Sea. It is bright orange and non-photosynthetic (azooxanthellate), lacking symbiotic dinoflagellates. Crucially for aquarists, it is a temperate, coolwater species rather than a tropical reef coral and should be kept in a coldwater marine system.
Taxonomy
- Order: Scleractinia
- Family: Dendrophylliidae
- Genus: Astroides
- Scientific name: Astroides calycularis
- Common names: Mediterranean Cup Coral, Star Coral
Habitat
The species is endemic to the western Mediterranean and also occurs in the Atlantic near the Strait of Gibraltar, with records in the Adriatic. It grows on rocks and walls, under overhangs and in submarine caves, down to about 70 m. Colonies form orange-yellow patches around 25–30 cm in diameter and up to 10 cm high. Its absence from the northern part of its range is linked to lower sea temperatures during glaciation.
Tank requirements
- Salinity: 1.024–1.026 SG
- Temperature: 16–22 °C (61–72 °F) — temperate, not tropical
- pH: 8.1–8.4
- dKH (alkalinity): 8–11
- Calcium: 400–450 ppm
- Magnesium: 1280–1350 ppm
- Nitrate: below 20 ppm; phosphate below 0.15 ppm
- Lighting: low (0–50 PAR)
- Flow: medium
- Minimum tank age: about 6 months
Feeding
As a non-photosynthetic coral, it depends entirely on feeding. In the wild its nocturnal polyps capture zooplankton and small prey. In aquaria it requires regular spot-feeding with foods such as mysis and reef-roids, supported by good filtration to handle the resulting nutrients.
Compatibility
Astroides is passive but uses stinging tentacles to feed, so neighbours should be kept clear. It is regarded as reef-, shrimp- and fish-safe, but its temperate temperature needs make it incompatible with a standard tropical reef community.
Astroides calycularis (Mediterranean Cup Coral): Propagation Guide
Overview
Astroides calycularis is a colonial coral in the family Dendrophylliidae, first described by Peter Simon Pallas in 1766; the genus Astroides is monotypic, containing only this species. Polyps are yellow or orange, each with a fringe of about thirty very short tentacles around a slit-shaped mouth, and colonies reach 25 to 30 cm in diameter and about 10 cm high. The species is endemic to the western Mediterranean Sea and expanded into the Adriatic in 1989.
Unlike many tropical reef corals, A. calycularis does not contain symbiotic dinoflagellates in its tissues. It feeds nocturnally on zooplankton, small fish and perhaps bacteria, with polyps remaining retracted into their calices during the day. It is also a temperate, not tropical, animal, which shapes any attempt to keep or grow it.
Reproductive Mode
The species uses dual reproductive strategies. It is gonochoristic, with all the polyps in a colony being of the same sex, for sexual reproduction. It also grows by asexual reproduction, with new polyps budding off existing polyps, which is how a colony enlarges over time.
Fragging / Asexual Propagation
Because the colony naturally enlarges through polyp budding, a colony fragment that carries living polyps and skeleton can in principle continue to bud and grow, much as the colony does in nature. The whitelisted source documents the budding mechanism but not a specific home protocol, so any division should keep intact polyps on each piece and rely on the coral's own budding to expand. Survival still depends on feeding and temperate conditions.
Feeding & Conditions for Propagation
Sustained growth and budding depend on supplying the zooplankton-scale foods the coral eats at night, together with the cooler, temperate water of its native western Mediterranean range. Bright lighting is not a substitute for food in this azooxanthellate species, and feeding is the practical driver of any propagation.