seen? This free-living coral with fat, white-tipped tentacles
is commonly seen on Pulau Hantu and Pulau Semakau and submerged reefs
nearby. They are often seen in shallow silty, sandy areas among seagrasses,
sometimes wedged among coral rubble. It used to be commonly seen on
Beting Bronok in the north. It is the only species in the genus Heliofungia
and is considered among the largest of polyps among hard corals.
Features: Circular skeleton 10-20cm
in diameter with a flat smooth base. It is also sometimes called plate
coral because its disk-shaped skeleton does resemble a dish. This
coral is free-living (is not attached to the surface) as an adult
and is a solitary polyp. The skeleton is light and the upper surface
has long continuous lines radiating from the single slit-shaped mouth
in the centre. These lines have large, rounded 'teeth'. The tissue
covering the upper surface is usually striped.
The tentacles are long, thick and cylindrical (they look like thick
'udon' noodles), usually brown but also bluish and even bright green.
Usually with white or cream tips that are sometimes inflated to a
Sometimes mistaken for a sea anemone
when its long tentacles obscure the hard skeleton. The hard skeleton
immediately identifies it as a hard coral. Here's more on how to tell
apart large 'hairy' cnidarians.
The Torch coral (Euphyllia
glabrescens) has tentacles that look similar to the sunflower
mushroom coral. But the torch coral's tentacles are smaller.
When the tentacles are retracted it resembles Fungia
mushroom hard corals but can be distinguished from Fungia
by the large, rounded teeth on the skeleton walls.
Status and threats: It is listed
as globally Vulnerable by
the IUCN which says that although "this species is widespread
and locally common throughout its range, it is heavily to harvested
for aquarium trade and has suffered extensive reduction of coral reef
habitat due to a combination of threats."
Pulau Hantu, Aug 03
Pulau Semakau, Aug 08
Large, lobed teeth.
Pulau Semakau, Jan 09
Young ones attached to a hard surface.
Pulau Semakau, Aug 08
The underside is flat (not concave)
Beting Bronok, Jun 03
Pulau Hantu, Apr 06
Pulau Semakau, Mar 05
Pulau Semakau, Apr 08
mushroom hard corals on Singapore shores
photos of sunflower mushroom hard corals on Singapore shores