hard corals text index | photo index
Phylum Cnidaria > Class Anthozoa > Subclass Zoantharia/Hexacorallia > Order Scleractinia > Family Faviidae
Zebra coral
Oulastrea crispata*
Family Oulastreidae
updated Nov 2019
if you 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.
Polyps on submerged portions may be extended, look for them.

Where 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. It was previously under Family Faviidae but is now placed in Family Oulastreidae.

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.

Lazarus, Apr 12

Pulau Hantu, Jan 12

Pulau Hantu, Jan 12

Pasir Ris, Aug 11

Changi, May 06

Pulau Ubin, Jun 08

Beting Bronok, Aug 05

*Species are difficult to positively identify without close examination.
On this website, they are grouped by external features for convenience of display.

Zebra hard corals on Singapore shores
On wildsingapore flickr

Other sightings on Singapore shores

Pulau Semakau East, Jan 16
Photo shared by Marcus Ng on facebook.

Terumbu Berkas, Jan 10

Pulau Pawai, Dec 09

Pulau Biola, Dec 09

Photo shared by Jamed Koh on his flickr.

Pulau Salu, Aug 10

Pulau Salu, Jun 10



  • 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. 2000. Corals 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.
  • Erhardt, Harry and Daniel Knop. 2005. Corals: Indo-Pacific Field Guide IKAN-Unterwasserachiv, Frankfurt. 305 pp.
  • Borneman, Eric H. 2001. Aquarium Corals: Selection, Husbandry and Natural History T.F. H Publications. 464 pp
links | references | about | email Ria
Spot errors? Have a question? Want to share your sightings? email Ria I'll be glad to hear from you!
wildfactsheets website©ria tan 2008