Acropora prostrata
Currently accepted name: Acropora millepora
The name Acropora prostrata is no longer valid: WoRMS considers it a synonym of Acropora millepora. 1 2 The data in this species sheet therefore concern A. millepora, a hard coral with low, short-branched colonies, common in the shallow waters of the Indo-Pacific. 1
At a glance
Data from the scientific sources listed at the bottom.
Depth in the wild
2–12 m
Conservation
IUCN Red List: endangered. CITES: Appendix II. The CITES listing in force dates from 18 January 1990 and applies to all Scleractinia. 3 The category is confirmed by GBIF and WoRMS. 1 4 Under the old name prostrata the Coral Trait Database still reports an outdated assessment of Data Deficient. 5
The coral
Group: SPS
Growth form: corymbose, sometimes tubular, with short branches
Zooxanthellae: yes
Growth: In the Keppel Islands, before bleaching, colonies with type D symbionts grew about 38% less than those with type C2; the 2006 bleaching cut growth by more than half for at least 18 months. 9
Where it lives
Kenya, Mozambique, South Africa and the Maldives; then India, Sri Lanka, Thailand, Malaysia, Singapore, Indonesia and the Philippines; as far as Japan, Taiwan, Australia and Pacific islands such as Fiji, Tonga, the Marshall Islands and American Samoa. 1 3
Life in the wild
Behaviour
Neighbouring colonies can fuse: in two Great Barrier Reef populations at least 2-5% of colonies were chimeras, that is, they contained several genetically different individuals. 8
In the aquarium
From the experience of the BallingMania community.
This splendid coral, in cream-brown, green, pink and blue, belongs to the family Acroporidae. Place of origin: the eastern Indian Ocean and the Pacific Ocean.
Very similar to the Acropora species pulchra and millepora; it differs from the latter in its less massive skeleton, its branches are less compact and evenly spaced, and the lips of the radial corallites are more brightly coloured.
Like Acropora millepora, it is vulnerable to attack by flatworms (Turbellaria), which may lay their eggs at the base of the coral.
photo by: Ciro Murino
What studies say about keeping it
Data from public aquarium research, not advice for a home aquarium. At the Horniman Museum in London a closed tank reproduced the light, lunar phases and seasonal temperature of the Great Barrier Reef: five A. millepora fragments completed their reproductive cycle and spawned. Compared with the wild, spawning came more nights after the full moon and in 2016-2017 lasted about three months. 7
Did you know?
Sources
- Hoeksema B.W., Cairns S., Samimi-Namin K. (2026). Acropora millepora (Ehrenberg, 1834). World List of Scleractinia, via WoRMS.
- Hoeksema B.W., Cairns S., Samimi-Namin K. (2026). Acropora prostrata (Dana, 1846), sinonimo. World List of Scleractinia, via WoRMS.
- UNEP-WCMC (2026). Acropora millepora, CITES listings and distribution. Species+.
- GBIF Secretariat (2026). Acropora millepora, IUCN Red List category. GBIF.
- Madin J. et al. (eds.) (2026). Acropora millepora: data from Carpenter 2008, Muir 2015 and studies on reproduction. Coral Trait Database.
- Cooper T.F., Berkelmans R., Ulstrup K.E. et al. (2011). Environmental Factors Controlling the Distribution of Symbiodinium Harboured by the Coral Acropora millepora on the Great Barrier Reef. PLoS ONE.
- Craggs J., Guest J.R., Davis M., Simmons J., Dashti E., Sweet M. (2017). Inducing broadcast coral spawning ex situ: Closed system mesocosm design and husbandry protocol. Ecology and Evolution.
- Puill-Stephan E., Willis B.L., van Herwerden L., van Oppen M.J.H. (2009). Chimerism in Wild Adult Populations of the Broadcast Spawning Coral Acropora millepora on the Great Barrier Reef. PLoS ONE.
- Jones A., Berkelmans R. (2010). Potential Costs of Acclimatization to a Warmer Climate: Growth of a Reef Coral with Heat Tolerant vs. Sensitive Symbiont Types. PLoS ONE.
Sources checked on 5 November 2026. Community texts and ratings are kept separate from the scientific data.