learn only 3 things about them ...
These small corals are common on stones and rocks. Don't
step on them!
They have a distinctive black-and-white skeleton.
on submerged portions may be extended, look for them.
seen? This hard coral with a black-and-white skeleton is
among the most commonly encountered of our hard corals. Even rather
'beat up' shores may have small colonies encrusting rocks and stones.
This hardy coral grows in murky waters and even where it is often
exposed to air at low tide. Elsewhere, the colonies are encrusting
and grow only to a few centimetres. Oulastrea crispata is
the only species in the genus.
Features: Colonies about 10-15cm,
sometimes much smaller. The colony tends to be encrusting, sometimes
a small boulder-shape. Corallites small (about 0.5cm) circular rings
with thick white radiating wall partitions (septa) on a black background.
The background remains black even after the colony is dead, thus its
common name. The polyps have many long thin tentacles and are brownish,
sometimes with a greenish tinge and a bright green mouth.
Some Montastrea species also of the Family
Faviidae may appear similar.
Status and threats: This coral
is not listed as globally threatened by
the IUCN. But like other creatures of the intertidal zone, they
are affected by human activities such as reclamation and pollution.
Trampling by careless visitors, and over-collection also have an impact
on local populations.
Kusu Island, Jun 05
Lazarus, Apr 12
Pulau Hantu, Jan 12
Pulau Hantu, Jan 12
Pasir Ris, Aug 11
Changi, May 06
Pulau Ubin, Jun 08
hard corals on Singapore Shores
*Species are difficult to positively identify without close examination.
On this website, they are grouped by external features for convenience of
crispata on Corals of the World online on the Australian
Institute of Marine Science website: Technical fact sheet.
crispata on the IUCN Red List of Threatened Species website:
Technical fact sheet.
crispata on Reef Corals of the Indo-Malayan Seas, the
Marine Species Identification Portal: Technical fact sheet.
crispata on SeaLife Base: Technical fact sheet.
- Danwei Huang,
Karenne P. P. Tun, L. M Chou and Peter A. Todd. 30 Dec 2009. An
inventory of zooxanthellate sclerectinian corals in Singapore
including 33 new records (pdf). Raffles Bulletin of Zoology
Supplement No. 22: 69-80.
- Veron, Jen.
of the World
Australian Institute of Marine Science, Australia. 3 volumes.
- Chou, L.
M., 1998. A
Guide to the Coral Reef Life of Singapore. Singapore Science
Centre. 128 pages.
Harry and Daniel Knop. 2005. Corals:
Indo-Pacific Field Guide
IKAN-Unterwasserachiv, Frankfurt. 305 pp.
Eric H. 2001. Aquarium
Corals: Selection, Husbandry and Natural History
T.F. H Publications. 464 pp